(navigation image)
Home American Libraries | Canadian Libraries | Universal Library | Community Texts | Project Gutenberg | Children's Library | Biodiversity Heritage Library | Additional Collections
Search: Advanced Search
Anonymous User (login or join us)
Upload
See other formats

Full text of "A laboratory manual of human anatomy"

/. ex 



MEDICAL SCHOOL 




Medical Library Exchange 
Washington University Scho 
of ^edicine Library 



iltrfrind ^ 



e) 



' j; < [ OF 

X 3 z 




E D i C A L D E PT 

^ashington (j 



^pH6?Sy 

A .ABORATORY 






OF 



HUMAN ANATOMY 



' 



LEWELLYS F. BARKER, M.B. TOR. 

PROFESSOR AND HEAD OF THE DEPARTMENT OF ANATOMY IN THE UNIVERSITY OF 
CHICAGO AND RUSH MEDICAL COLLEGE 



ASSISTED BY 

DEAN DE WITT LEWIS, A.B., M.D. AND DANIEL GRAISBERRY REVELL, A.B., M.B. 

INSTRUCTORS IN ANATOMY IN THE UNIVERSITY OF CHICAGO 



ILLUSTRATED 



PHILADELPHIA AND LONDON 

J. B. LIPPINCOTT COMPANY 

1904 



COPYRIGHT, 1904 

BY 
J. B. LIPPINCOTT COMPANY 




ELECTROTYPED AND PRINTED BY J. B. LIPPINCOTT COMPANY, PHILADELPHIA, U.S.A. 



Hot 



PREFACE 



MANY instructors in anatomy have for some time felt the 
need of more systematic, more orderly, and more thorough work 
in the dissecting-room. Anatomy, one of the first sciences to 
be taught by the laboratory method, has not always kept pace 
with her younger sister sciences in the advance of methods of 
instruction. A number of laboratory manuals are, it is true, 
available ; but it has been complained that even the best of these 
is unsatisfactory, partly on account of nomenclature, partly 
because so much is included that the student tends to lean 
entirely upon his manual, rather than to observe at first hand 
for himself and to consult larger text-books and atlases. So 
convinced have some anatomists become of the inadequacy of 
present manuals that they have banished all dissecting guides 
from their laboratories, and insisted upon their students work- 
ing with no guide whatever except large atlases and text-books 
and occasional hints from the instructor. This latter plan has 
worked very well in some instances, especially where men enter- 
ing upon the study of medicine had previously undergone rigid 
laboratory training in physics, chemistry, and biology. But 
even such men had to pass through a period of doubt, perplex- 
ity, and discouragement before they became independent dis- 
sectors, and some of them completely failed to do so. Students 
without such preliminary training in science are very apt to 
be utterly lost if thrown entirely or almost entirely upon their 
own resources, especially where classes are large and more than 
ten students have to be cared for by one instructor. It is 
believed that the use of the Laboratory Manual here presented 
will enable the good student to become an independent worker 
much more quickly than wien b^. is left without such guidance ; 
he will be able to do his wora in less time and can assure himself 
that he is doing it thoroughly, using the Manual, if he prefer, 
merely as a control of his work ; at the same time the student 
who is less well-equipped will be gradually led into independent 
work, to which he might otherwise never attain. 

There should be also a marked saving of time and energy for 
the instructor, a matter of no little importance if he is to make 



vi PREFACE 

contributions to knowledge by original investigation in his 
department. There is no intention, however, to make " word of 
mouth" instruction superfluous. On the contrary, it is hoped 
that the use of the Manual will make it possible for the in- 
structor to concentrate his attention upon, and to give better 
than before, that particular help to the student which comes 
alone through the personal encounter. 

Whether the effort to find the golden mean between the 
" spoon-feeding" guide, on the one hand, and insufficient guid- 
ance, on the other, has been successful must be left to anatomical 
teachers to decide. The compilers have used the Manual in 
mimeograph form during the past year in the Anatomical Lab- 
oratory of the University of Chicago ; instructors and students 
both feel that it has been distinctly helpful. 

The sequence of dissection and the methods of exposing the 
various parts are those almost universally adopted in the better 
English and American laboratories. They represent the expe- 
rience and traditions of more than a hundred years of careful 
anatomical work. The influence of the Edinburgh school of 
anatomists has become widespread, and the directions of one 
of the principal representatives of that school, Professor D. 
J. Cunningham, of Edinburgh, as embodied in his admirable 
Manual of Dissection, have been closely followed herein. 

The Laboratory Manual is not intended to take the place of 
a descriptive text-book (see p. 30) ; on the contrary, it is hoped 
and expected that it will act as a stimulant to the student not 
only to use in connection with it the best descriptive text-book 
and atlas available, but also to refer to various atlases and text- 
books, as well as original articles in the literature. Though it 
is realized that the average medical student has not the time 
to range far afield, it would seem highly desirable that he 
should at least gain an idea of the wide extent of the subject and 
that he should learn that it is not all included between the covers 
of a dissecting manual. 

The nomenclature employed is that which was formulated by 
the German Society of Anatomists and which is rapidly being 
adopted in many of the best English and American laboratories. 
There seems to be no doubt that this nomenclature will be the 
prevalent one for at least many years to come. The magnificent 
atlases of Spalteholz and Toldt, which have recently been pub- 
lished, employ it exclusively, and the student will find it a great 
convenience to have the terms used in his laboratory manual 
identical with those of his atlas. Unfortunately, only one or 



PREFACE 



vn 



two of the most recent descriptive text-books of systematic 
human anatomy by English writers have yet adopted this nomen- 
clature. It is earnestly to be hoped that an advance will quickly 
be made in this direction and that text-books will employ it uni- 
formly. Special attention is drawn to the fact that in the fol- 
lowing Laboratory Manual the old terms, when different from 
the new, have been added in parentheses, so that the student 
need never be embarrassed in finding his way even in a de- 
scriptive text-book or atlas in which only the old terms are 
employed. He is advised, however, when purchasing a text- 
book to give preference to one in which the new nomenclature 
[BNA] is consistently employed. 

Indulgence is asked for misprints and errors almost certain 
to occur in the first edition of a work including such an enor- 
mous number of names as is involved in a subject like human 
anatomy. Should the Manual find enough friends to make a 
second edition desirable, many improvements can doubtless be 
made, and suggestions from instructors and students of anatomy 
will be cordially welcomed. 

The Manual contains about 300 illustrations, of which a 
special index is given. The drawings and plates represent in 
a very satisfactory way the most important structures of the 
body. These illustrations have been chosen to serve as a valu- 
able atlas to students who feel that they cannot afford to buy 
one of the more expensive atlases like those of Spalteholz and 
Toldt. On the other hand, students who own Spalteholz 's At- 
las, the one especially recommended for use in connection with 
this Manual, will find that the illustrations have been selected 
with the special aim of supplementing those of Spalteholz, and 
that they will prove a valuable addition to the latter. 

The Anatomical Atlas of Toldt, from which many of the 
illustrations in this Manual have been borrowed, can be very 
highly recommended; every student who can afford to do so 
should purchase it for his library. 

CHICAGO, October 1, 1904. 



TABLE OF CONTENTS 



INTRODUCTION 

PAGE 

GENERAL 17 

INSTRUMENTS 19 

PRESERVATION OF THE PART 24 

CLOTHING 26 

DRAWING 26 

BOOKS 30 

Library 30 

DIVISION OF THE CADAVER INTO PARTS 34 

ANATOMICAL TERMS OF POSITION AND DIRECTION 34 

GENERAL ANATOMICAL TERMS . . 36 



Part I. 



UPPER EXTREMITY. 

ARM AND WALL OF THORAX 41 

SURFACE ANATOMY 41 

REGIONS OF THE BACK 45 

ANTERIOR THORACIC REGION AND AXILLARY FOSSA 51 

REGION OF THE SHOULDER 68 

ARM AND FOREARM 73 

SHOULDER- JOINT 84 

FOREARM AND HAND 87 

WRIST AND PALM 96 

DORSAL SURFACE AND RADIAL MARGIN OF FOREARM 104 

DORSUM OF WRIST AND HAND 106 

JOINTS . 109 



Part II. 



LOWER EXTREMITY. 

INTRODUCTORY 121 

GLUTEAL REGION 123 

POPLITEAL FOSSA 129 

POSTERIOR SURFACE OF THIGH 135 

ANTERIOR SURFACE OF THIGH 138 

MEDIAL SURFACE OF THIGH 152 

HIP- JOINT 154 

LEG AND FOOT 156 

ix 



x CONTENTS 

PAGE 

LATERAL REGION OF LEG 163 

MEDIAL REGION OF LEG 165 

POSTERIOR REGION OF LEG AND HEEL 165 

PLANTAR REGION OF FOOT 174 

KNEE-JOINT 180 

TlBIOFIBULAR JOINTS 184 

ARTICULATION OF THE FOOT 185 

ARTICULATIONS OF TOES . . 190 



Part III. 



HEAD AND NECK AND DORSUM OF TRUNK. 

SCALP 194 

OPENING THE CAVITY OF THE SKULL 197 

REMOVAL OF BRAIN 199 

SIDE OF NECK 204 

MEDIAN LINE OF NECK 222 

BACK OF HEAD, NECK, AND TRUNK 228 

THE SPINAL CORD 242 

FACE 247 

TEMPORAL REGION AND RETROMANDIBULAR FOSSA 260 

PTERYGOID REGION AND JOINT OF JAW 261 

MANDIBULAR CANAL AND SUBMAXILLARY REGION 264 

DEEP DISSECTION OF NECK 267 

MIDDLE CRANIAL FOSSA 272 

ORBIT 275 

REGION IN FRONT OF CERVICAL SPINE 282 

LIGAMENTS OF VERTEBRAL COLUMN AND SKULL 286 

MOUTH AND FAUCES 288 

PHARYNX 291 

CAROTID AND INFRAORBITAL CANALS 297 

SAGITTAL SECTION OF FOREPART OF HEAD NEAR MEDIAN PLANE 298 

Otic Ganglion 299 

Cavity of Nose '. 300 

Sphenopalatine Ganglion 303 

Intraosseous Course of some Cerebral Nerves 305 

LARYNX 307 

TONGUE 315 

BRAIN 317 

Membranes of Brain 317 

Blood- Vessels of Brain 318 

Removal of Meninges and Superficial Blood- Vessels 322 

Cerebral Nerves 322 

Larger Subdivisions of the Brain 324 

External Morphology of Rhomboid Brain and Midbrain 326 

Medulla Oblongata 326 

Pons [Varolii] 327 

Isthmus of Rhombencephalon 327 

Midbrain 328 

Cerebellum 328 

Fourth Ventricle . . 330 



CONTENTS xi 

PAGE 

BRAIN : 

External Morphology of Forebrain 331 

End-brain 332 

Hemisphere 332 

Brain Mantle 332 

Lobes of Cerebrum 333 

Medial Surface of Hemisphere 336 

Island 337 

Olfactory Brain 337 

Hypothalamus 338 

Corpus Callosum 338 

Lateral Ventricle 339 

Septum Pellucidum 343 

Fornix 343 

Thalamencephalon 346 

Third Ventricle 346 

Sections through Brain 347 

Sections of Medulla Obiongata 347 

Sections of Pons 353 

Sections of Cerebellum 354 

Section of Rhombencephalic Isthmus, Corpora Quadrigemina, and 

Cerebral Peduncle 356 

Sections of Hypothalamus 360 

Sections of Thalamencephalon 362 

Sections of Telencephalon 362 

Conduction Paths of the Nervous System 364 

Descending and Ascending Fibre Systems in Spinal Cord 365 

Fibre Systems of Cerebral Nerves 365 

Conduction Paths of Cerebellar Peduncles 369 

Conduction Paths of Diencephalon and Telencephalon 372 

Projection Fibre Systems 372 

Associative Fibre Systems 373 

ORGAN OF VISION 375 

Introductory 375 

Fibrous Coat of Eye 376 

Sclera 378 

Cornea 378 

Vascular Coat of Eye 379 

Chorioid 379 

Ciliary Body 379 

Diaphragm of the Eye (Iris) 380 

Layer of Pigment 381 

Retina 381 

Vitreous Body 382 

Ciliary Zonule 383 

Crystalline Lens 383 

Chambers of Eyeball 384 

ORGAN OF HEARING 384 

Introductory 384 

External Acoustic Meatus 385 

Cavity of Tympanum 385 



xii CONTENTS 

PAGE 

ORGAN OF HEARING: 

Membrane of Tympanum 387 

Tympanic Mucous Membrane 388 

Auditory Ossicles 388 

Joints and Ligaments of the Auditory Ossicles 390 

Muscles of Auditory Bones 391 

Osseous Labyrinth 391 

Membranous Labyrinth 394 



Part IV. 

THORAX. 
(WALLS AND VISCERA.) 

INTRODUCTORY 399 

INTERCOSTAL MUSCLES 399 

INTERCOSTAL NERVES 400 

INTERCOSTAL VESSELS 401 

INTERNAL MAMMARY ARTERY 402 

TRANSVERSE MUSCLE OF THORAX 402 

THORACIC CAVITY 403 

PLEURA 403 

EXPLORATION OF PLEURAL CAVITY 405 

REMOVAL OF CENTRAL PORTION OF STERNUM 407 

LUNGS 407 

ROOT OF LUNG 408 

PHRENIC NERVE AND CARDIAC PLEXUS 409 

PERICARDIUM 410 

THYMUS 411 

GREAT VEINS OF THORAX AND THEIR TRIBUTARIES 411 

HEART AND AORTA 412 

TRACHEA AND BRONCHI 424 

POSTERIOR MEDIASTINAL CAVITY AND ITS CONTENTS 424 

INTERIOR OF THE LUNGS 426 

THORACIC PORTION OF SYMPATHETIC NERVOUS SYSTEM 428 

WALL OF THORAX FROM WITHIN 428 

JOINTS OF THORAX . 429 



Part V. 

ABDOMEN AND PELVIS. 

INTRODUCTORY 433 

PERINEAL REGION 434 

MALE PERINEUM 436 

UROGENITAL REGION IN THE FEMALE 444 

ANAL REGION AND DIAPHRAGM OF PELVIS IN BOTH SEXES 449 

ANTERIOR ABDOMINAL WALL . . 451 



CONTENTS xiii 

PAGE 

PERITONEUM AND ABDOMINAL VISCERA 462 

Developmental Relations 462 

Great Omenturn 467 

Lesser Omentum 468 

Mesentery 468 

Mesocolon 468 

Mesorectum 469 

Fossae and Plicae 470 

Omental Bursa 472 

Peritoneal Ligaments 472 

Superior Mesenteric Artery 474 

Superior Mesenteric Vein 476 

Superior Mesenteric Plexus 476 

Inferior Mesenteric Vessels and Nerves 477 

Small Intestine 479 

Large Intestine 485 

Structures in Lesser Omentum 489 

Coeliac Artery 491 

Duodenum 492 

Pancreas 495 

Vagus 497 

Stomach 498 

Abdominal Sympathetic 500 

Spleen 501 

Liver 502 

Gall Bladder 505 

UROPOETIC ORGANS 505 

Kidney 506 

Ureter 509 

Suprarenal Glands 509 

MUSCLES AND VESSELS IN THE ABDOMEN 511 

NERVES IN THE ABDOMEN 516 

DISSECTION OF THE MALE PELVIS 519 

Peritoneal Folds 519 

Hypogastric Plexus 519 

Pelvic Fasciae 520 

Rectum 524 

Urinary Bladder 525 

Prostate 525 

Seminal Vesicles 527 

Deferent Duct 527 

ARTERIES OF THE PELVIS 528 

VEINS OF THE PELVIS 533 

MUSCLES AND NERVES OF THE PELVIS 533 

PELVIC VISCERA 536 

Rectum 536 

Urinary Bladder 537 

Male Urethra 539 

Wall of Seminal Vesicle 539 

DISSECTION OF THE FEMALE PELVIS 540 

Peritoneum . 541 



xiv CONTENTS 

PAGE 

DISSECTION OF THE FEMALE PELVIS: 

Hypogastric Plexus 541 

Pelvic Fascia 541 

Vessels and Nerves 542 

Rectum 542 

Bladder 543 

Ureter 543 

Uterus 543 

Vagina 545 

Ovary 546 

Uterine Tube 546 

Round Ligament 547 

Diaphragm of Pelvis 547 

Rectum 548 

Urethra 548 

Interior of Vagina 549 

Interior of Uterus 549 

Interior of Uterine Tube 550 

JOINTS OF THE PELVIS 551 



INTRODUCTION 



THE anatomical laboratory has the longest history of all the 
medical laboratories. The student has the experience of hun- 
dreds of years to draw upon. The best methods of isolating 
the various structures have been worked out and certain rules 
for dissection have been formulated; the student will do well 
to familiarize himself with these as early in his course as pos- 
sible. 

Careful, practical work in the dissection-room is the only 
means the medical student has of obtaining an independent view 
of the gross structures of which the human body is composed. 
Text-books, atlases, demonstrations, and lectures are useful aids, 
helpful in exciting interest, and favorable to the acquisition of 
powers of description and illustration; but the main part of 
the work in anatomy should consist of the student's personal 
observation. He should learn to see what comes under his eye. 
He should try by his own independent activity to see all that is 
there, for the student who learns to see only what he is told to 
see or what is pointed out to him will be spoiled for the study 
and practice of medicine. 

Many students in the past have entered the dissecting-room 
with an utter lack of independent power of observation, of ex- 
amination, and of description, and yet these three qualities are 
absolutely necessary for the man who is to engage successfully 
in the practice of medicine. While it is to be hoped that the 
advance in the requirements for admission to professional 
schools, leading as it does to observational work in physics, 
chemistry, and biology preliminary to the work of the medical 
course, will bring the students to our laboratories of anatomy 
better prepared than hitherto for the independent observation 
of anatomical structures, there can still be but little doubt that 
many students will learn how really to study and observe first 
in the dissecting-room. How important it is that the habits 
formed at this early period of the professional course should 
be such as will be of value to the student later, such as he would 
desire to have throughout his professional career ! If he have 
learned to be exact and steady, systematic and thorough, cleanly 
2 17 



18 INTRODUCTION 

and artistic, in his work in the dissecting-room, how much better 
for him than if at the outset of his career he become satisfied 
with superficial observation, with interrupted and irregular 
activity, with disorder and uncleanliness ! The habits formed in 
the anatomy building have their effect upon the whole life of the 
physician. 

Moreover, the very first dissection may be all-important as 
regards the subsequent dissections. He who fails in his earliest 
dissection to acquire the habit of working according to a definite 
method seldom learns later to become an exact, quick, and careful 
dissector. It is almost hopeless to try to make a man do exact 
and clean work in the dissecting-room after he has once formed 
inaccurate and dirty habits. The student in the beginning 
should aim not so much at rapidity as at method. When he has 
once formed the habit of proceeding always according to a care- 
ful method, the rapidity will quickly follow. 

It is sometimes asked, " Why should the medical student 
spend so much time and take so much pains in making a careful 
and beautiful dissection? Is it not time wasted to work out the 
smaller branches of the nerves and blood-vessels?" Expe- 
rienced teachers who require thorough work are not disturbed 
by such inquiries. Those who have had the best opportunity 
for judging assert that it is only when a man succeeds in making 
a fine dissection that he gains an interest and pleasure in an 
occupation which may not at first be attractive to him. Further, 
the importance of working out the finer structures lies not 
always so much in the actual knowledge of these structures 
gained by the student, as in the acquisition of the habit of thor- 
oughness of observation and investigation. The medical student 
who in the dissecting-room dissects out only the main trunks of 
the vessels and nerves, or only the structures which at the 
moment seem to physicians and surgeons of greatest practical 
import, is likely as a clinician to be satisfied with the detection 
of the more obvious and superficial symptoms, to the overlooking 
of the less prominent symptoms and the more obscure physical 
signs. The thorough dissector is much more likely later to 
become a finely discriminating physician and an effective pro- 
gressive surgeon. Again, if a dissector permit himself to expose 
structures roughly, to isolate them incompletely, and to clean 
them imperfectly, so that his dissection becomes indistinct, bad- 
smelling, and repulsive-looking, he will quickly lose interest in 
his work, slice the part desperately, neglect it, stay away from it, 
and fail utterly to benefit by it. Each student should, therefore, 



INTRODUCTION 19 

at the beginning, err, if at all, upon the side of over-exactness 
and over-carefulness in the use of instruments, in the methods 
of handling anatomical objects, and in the isolation of the details 
of structure. He should at first force himself to follow estab- 
lished rules and regulations rigidly ; if desirable, later on in his 
work he may allow himself more latitude. He should aim to 
make his dissection such that he may at any moment and without 
embarrassment turn it over to an instructor who may wish to 
deliver a lecture on the part; he should aim to do his work so 
carefully that an artist may satisfactorily make a drawing of it 
to illustrate a text-book. 

While a large portion of the student's time in the early part 
of the dissection is occupied with the technique of the work, 
learning how to find the various structures and to demonstrate 
them properly, he should not forget that the mere mechanical 
side of the work, important as it is, is not the only side. It is 
necessary that he should also study the structures carefully, 
learn their names, examine their relations, and, above all, under- 
stand their significance. Atlases, text-books, models, and moist 
and dry preparations should be assiduously used in connection 
with the dissection of the part, if the student is to acquire in the 
anatomical laboratory the knowledge and skill which it is de- 
sired that that laboratory shall give him at the beginning as a 
basis for his other medical studies. 



INSTRUMENTS NEEDED. 

Each student should provide himself with a good set of dis- 
secting instruments made by a reliable manufacturer. They 
should be made of good steel, properly tempered and well 
ground. It is false economy to buy cheap instruments or to 
secure a set at second hand. The quality of the student's work 
will be much influenced by the kinds of instruments he uses and 
the state in which he keeps them. A good set of dissecting in- 
struments will not cease to be valuable to the medical student 
when he finishes his dissection, but will be found convenient for 
many purposes during his subsequent practical life. 

The sets supplied by the manufacturers vary greatly in ex- 
tent and quality, and the student may find it advantageous to 
make up a set for himself, choosing the individual instruments 
from stock, rather than to purchase any regular dissecting-case 
offered. As a minimum the student should possess : 



20 INTRODUCTION 

1. One cartilage-knife (with bellied blade). 

2. Three dissecting scalpels with bellied blades, one large, one of medium 

size, and one small. 

3. Two dissecting scalpels with straight edges and sharp points, one long 

and one short. 

4. One pair of medium-sized scissors. 

5. One pair of small scissors. 

6. One blunt probe (Mall's). 

7. One large dissecting forceps. 

8. One tubulus or blowpipe. 

9. One sound (fishbone or metal). 

10. One good curved needle and sutures. 

11. One good razor-strop. 

12. A medium-sized sponge. 

Other instruments, including mallet and chisels, saws, rhachi- 
otome, myelotome, enterotomes, and bronchial scissors, will be 
supplied by the laboratory. 

The student may find it desirable to have more scalpels than 
are required above ; if so, he will find it best to have more belly- 
bladed knives than knives with straight edges. 

When purchasing forceps, the greatest care should be ex- 
ercised, for it is rare to find properly constructed samples. The 
branches should be relatively strong, not too flimsy; on closing 
they should come together almost with the weight of the thumb 
and finger, as nothing grows more tiresome than forceps which 
are too stiff to close easily. Forceps with well-worked-out points 
should be chosen, so that they will grasp fine structures with cer- 
tainty. The points should not slide over one another on closing. 

CAKE OF INSTRUMENTS. 

The best instruments are quickly ruined where no care is 
taken to prevent injury or deterioration. If scalpels and forceps 
are permitted to fall frequently to the floor, or if cutting instru- 
ments are thrown carelessly in contact with other instruments, 
their value as dissecting implements rapidly diminishes. 

Knives should be kept sharp and smooth-cutting. This is 
absolutely necessary if the student is to do good work, for it is 
impossible to dissect neatly and quickly with dull knives. The 
strop, if used at short intervals, say, every ten or fifteen min- 
utes, will keep a smooth-cutting edge on a sharp knife and 
increase its power of penetration. A knife properly sharpened 
and preserved from gross injury may be kept in good condition 
for a long time without honing or grinding if it be properly and 
frequently stropped. 



INTRODUCTION 21 

When a knife becomes dulled and stropping is no longer suffi- 
cient to renew its edge, it should be honed. So few men learn 
how properly to hone a knife that it has been questioned whether 
students had better attempt it themselves or turn their scalpels 
over to an instrument-maker to be honed. Still, as one needs also 
to know how to keep a microtome-knife in repair, it is an advan- 
tage to learn to do the honing one's self. A good oil-stone or Ar- 
kansas stone is necessary. The knife, held obliquely, is drawn 
to and fro with the edge in advance, the stroke extending from 
the heel along the whole length to the toe of the blade. Ex- 
perience under some one who is skilled is very desirable, that one 
may know the exact angle of inclination to employ, and the point 
when the blade has been sufficiently honed, for after a time a 
continuance of the honing only does harm. Much skill and ex- 
perience are required to get exactly the right thinness of edge. 
It is to be borne in mind that dissecting knives ought not to be so 
thin as a surgical knife, where quick penetration is all-important 
and the knife is to be used only for a short period, for such 
knives are quickly dulled. 

After repeated honing a knife may lose all its thin edge ; it 
should then be ground. 

The student should avoid injuring his scalpels by cutting 
against bone or the end of the forceps. It is well to keep one 
coarse knife especially for cutting near the bone or through 
calcified tissues. 

All instruments should be cleaned and rubbed thoroughly 
dry before they are put away at the end of a day's work. If a 
dissection has been completed and the instruments are to be 
laid aside for some time, they should be boiled for ten minutes 
in a one per cent, solution of sodium carbonate, thoroughly dried, 
and lightly coated with clean vaseline. This sterilizes them com- 
pletely and helps to prevent rust. 

USE OF INSTRUMENTS. 

Scalpel. One of the most important things for the student 
to learn in technique is the use of the convex or belly-bladed 
scalpel. This blade has a long cutting edge, and is employed for 
making large cuts or for cutting large surfaces; it is unsuited 
for small, careful cuts or for dissecting in angles or in the depth. 
The convex scalpel is used chiefly in dissecting the skin, fascia, 
and muscles, and in general where large incisions are to be 
made and the work is relatively gross. In the dissection of 
vessels and nerves, on the other hand, the larger belly-bladed 



UBARV 



22 INTRODUCTION 

scalpels should never be used; even the smallest ones must be 
very carefully employed for such dissection, or important struct- 
ures will be injured. 

The scalpel with the straight edge and sharp point has a use 
entirely different from that of the belly-bladed knife. Although 
the blade of the knife with the straight edge may be quite long, 
one uses only the point of the knife in dissection ; the action of 
such a knife is, therefore, much more limited than is that of the 
belly-bladed scalpel, and it should be used in making only the 
smaller, less extensive cuts. Students are frequently seen try- 
ing unsuccessfully to make large incisions with such knives, 
especially when their convex blades are dull. The scalpel with 
straight edge and sharp point is especially valuable in the dis- 
section of the viscera, sense organs, blood-vessels, and nerves. 
It may well be employed whenever a small, careful cut is to be 
made, and it will be found of the greatest convenience when the 
student is working in corners or in deep fossae. 

The dissector should early learn the right way to hold a scal- 
pel. The manner of holding in the dissecting-room is quite 
different from that in the autopsy-room of the pathologist. In 
the former case and in surgical work the knife is to be held ' ' like 
a pen," between the thumb and the first two fingers, the handle 
of the scalpel pointing obliquely upward. In the post-mortem 
room the pathologist usually holds his knife " in his fist," the 
handle of the scalpel being raised only slightly above the level 
of the blade and resting in the palm of the hand. The only time 
the dissector in the laboratory of human anatomy is permitted 
to hold the knife " in his fist" is when he makes a long incision 
through tough skin ; in all other circumstances the knife should 
be held ' ' like a pen. ' ' 

The thumb, index and middle fingers should alone be used in 
holding the knife ' ' like a pen. ' ' The ring-finger should not be 
permitted to touch the knife, no matter how much the dissector 
is inclined thereto. Only by following this rule can the anatomi- 
cal workman secure the necessary freedom and acquire the deli- 
cacy of movement requisite to good work. The ring-finger and 
the little finger will be found very useful in making tissues tense, 
in retracting tissues, or in displacing them to the side. 

The scalpel should be grasped by the thumb and fingers at 
about the junction of blade and handle, certainly not high up on 
the handle, certainly not far down on the blade. In making 
careful cuts the hand should be supported upon its ulnar margin. 
This support permits of greater precision ; the cut desired may 



INTRODUCTION 23 

be made with sureness and steadiness and without anxiety. The 
student should keep his finger- joints nimble, and should practise 
to acquire increased mobility of these joints. The skill gained 
in the use of instruments in the dissecting-room may be of great 
value in subsequent surgical practice. 

The importance of having several belly-bladed knives and 
several knives with straight edges has been referred to above. 
No good dissector cares to use the same knife for working out 
skin, vessels, muscles, nerves, etc. There should be a " division 
of labor" among scalpels. Hard, firm, tough tissues should be 
cut through only with the cartilage-knife or with a duller scalpel. 

Forceps. These should be held in the left hand, " like a 
pen," between the thumb and first two fingers, the ring-finger 
and little finger being reserved for the support of the hand and 
never permitted to touch the instrument. The forceps should 
never be held * ' in the fist. ' ' They should be grasped about the 
middle, not too high up, and the fingers should not be cramped, 
otherwise the hand tires too quickly. The support of the hand 
on its ulnar margin by means of the little finger and the ring- 
finger is important, as it helps to make the work more exact and 
more certain. 

Scissors. These should be grasped by the thumb and middle 
finger. The scissors are generally used where the parts to be 
cut through are soft, yielding, and easily displaceable and do 
not offer much resistance to the edge of the knife. Scissors are 
much employed by many dissectors in the study of the viscera 
and of the blood-vessels. They are especially valuable in fol- 
lowing out through loose connective tissue or fat the finer 
branches of arteries and veins, which might be more easily cut 
if the knife were used. Like the straight-edged scalpel with a 
sharp point, scissors are useful in cutting in angles or corners 
and in deep places. Fat held in the forceps can be most easily 
removed with scissors. Very fine scissors are useful in the dis- 
section of delicate nerves and of the small muscles of the face 
and orbit, but in general scissors are little suited to the dissec- 
tion of muscles and nerves. 

Probe. The flimsy probes usually supplied in dissecting sets 
are of but little use and should be discarded. The firm probe 
devised for use in Baltimore by Professor Mall is the best one 
available. Many students do a very large part of their dissec- 
tion with this probe. It is especially useful for the beginner, 
who is afraid of destroying important structures with the knife. 
The " blunt dissection" which the probe permits of insures the 



24 INTRODUCTION 

working out of many structures which would otherwise be cut 
away. In using the dissecting-probe the least force necessary 
to the purpose should be brought into play, the strength of the 
tissues being, as it were, continually tested, and the loose tissue 
between the definite structures being gently removed by repeated 
light strokes instead of by a few strong sweeps of the probe. 
" Wear away rather than tear away!" This will avoid giving 
the muscles a ragged appearance and will also preserve many 
small and delicate structures which would otherwise be lost. 

There is danger, however, of over-use of the method of blunt 
dissection with the probe. It is highly important that the stu- 
dent should gain skill with the scalpel, and this he can do only 
by constant practice with it. Again, where the probe is used 
instead of the scalpel, it is not possible to make so clean a dissec- 
tion as the student should require of himself. The structures are 
left ragged, and the artistic sense of the dissector remains unde- 
veloped, or, if developed, is offended. 

PRESERVATION OF THE PART. 

A large portion of the pleasure in his work and of the benefit 
to be derived from it will be lost if the student neglects to take 
proper care of the part while he is dissecting it and during the 
intervals between the periods of dissection. If a part be allowed 
to become dirty, if it be permitted to dry up, or if it become foul, 
the student will lose interest in it, will tire of it, and will inevi- 
tably neglect it. If the part has been well preserved in the first 
place, its preservation after arrival in the dissection-room 
depends entirely upon the student. If he handle it properly and 
protect it carefully, he can keep it in prime condition until the 
dissection has been completed. 

Drying of the part is the greatest of all dangers. The 
moment the tissues become dry, knives are dulled in dissecting 
them and it quickly becomes impossible to isolate the finer struct- 
ures, which, moreover, lose their natural color and form. In 
addition, the part grows repulsive to sight. 

The skin of the cadaver is one of the best protectives against 
drying. Skin when removed should always be kept as a covering 
for the part. When the dissection is put away at the end of a 
working period, it should be wrapped carefully in the integu- 
ment, which should be securely fastened by tying or pinning it 
in place. Some careful dissectors take the trouble to secure 
cutaneous flaps in position by stitches each time the part is put 
away. 



INTRODUCTION 25 

In addition, the part should be thoroughly wrapped in gauze 
or cheese-cloth saturated with a three per cent, solution of car- 
bolic acid or other preserving fluid and held in place by twine. 
It is convenient to have a large quantity of the preserving fluid 
in a tub in the dissecting-room, out of which the wrappings may 
be wrung by hand or by a laundry wringer. The gauze or cheese- 
cloth should be folded into a convenient shape and size. a few 
inches longer than the part to be covered and about eighteen 
inches wide. After being moistened in the preservative fluid, it 
may be wrapped about the part and secured by tapes or twine. 
Such a covering is readily and quickly removed when the part 
is required for work. It is also very useful for covering such 
portions as are not immediately under dissection or study. As 
an additional protection against drying, a piece of oil-cloth, 
about a foot square, is advisable for the hand, foot, and face. 

As soon as possible after the cadaver is placed on the table, 
the student should take charge of his part, wrap it up, and attach 
to it a label bearing his name. 

Not only in the intervals between the dissection periods, but 
also during working hours, care should be taken to prevent dry- 
ing. Parts not in actual use should be kept covered, for even 
two hours ' exposure causes drying which deteriorates the mate- 
rial. The portion of the dissection actually being worked upon 
should be moistened occasionally with a wet sponge. The best 
results are attainable only if the material be kept in good condi- 
tion; it is not possible to restore dried-out material to as good 
condition as it was in before drying or partial drying. Especial 
care should be taken to protect parts belonging to students not 
present. 

The cadaver should be kept raised on dissecting-blocks, so as 
to allow free drainage away of the fluids which otherwise cause 
the under parts to become macerated and offensive. The drain- 
pipe in the centre of the table must be kept unobstructed. 

Cleanliness about the dissection-table should be cultivated. 
Bits of fat and connective tissue which are removed should never 
be allowed to contaminate the wrappings of the part or the table 
itself. They should be collected on a piece of paper or cloth and 
then thrown into the refuse-pail. The student should leave his 
dissection and the dissection-table in perfect order and condition 
at the close of each day's work. A little care exercised in the 
formation of orderly and cleanly habits at this period of his 
development will be of great service to the student in his sub- 
sequent work. 



26 INTRODUCTION 

CLOTHING. 

The better methods of preserving the material for dissection 
prevalent nowadays have removed some of the unpleasant feat- 
ures of the occupation. It is not possible, however, to avoid all 
odor or all contamination, and the student should, therefore, go 
to the dissecting-room clad in a manner which will permit him 
to work freely and without constant worry lest his clothing come 
into contact with the material. Hence it is necessary to have an 
old coat to be kept for use in the dissecting-room only, and it is 
preferable to change the whole suit on entering and on leaving 
the room. As a roomful of men garbed in old coats is not a 
pleasing spectacle, it is the custom in modern anatomical labora- 
tories to wear white cotton gowns over all. The student should, 
therefore, provide himself with three such gowns, so that he may 
always have the soiled ones laundered while the clean one is 
being worn. Gowns other than white should be avoided, as 
should the various oil-cloth sleeves and aprons formerly so much 
used. No inconsiderable part of the depressing influences of 
the old-time dissecting-room consisted of the dirty floors, the 
untidy tables, the tobacco-smoke, the spittoons, the oil-cloth 
sleeves and aprons, and the multicolored or checked gowns. 

Dissection is a serious task, requiring much energy and en- 
durance. Under the best conditions the student tires all too 
quickly. It is important, therefore, that the sanitary conditions 
of the room be the best possible, that as comfortable a position 
as practicable be assumed in dissecting, that the dress be one 
which while externally uniform throughout the room will permit 
of the . greatest freedom in work, and that all depressing in- 
fluences be as far as possible removed. 

DRAWING IN GBOSS ANATOMY. 

The student should not try to draw all that he sees, but only 
so much as is important in the stage represented. He should 
limit the contents of each picture to what can be shown clearly, 
and try to avoid unimportant detail. 

The drawing is to be made large enough to show clearly all 
that it contains. In general, it should be as large as the size of 
the drawing-paper will permit, allowing for the legend. It is 
well to make the drawing on a definite scale, and to record on it 
the proportion which the size of the picture bears to the natural 
size, using a fraction to express this, e.g., Vs, V 2 , Vi, Vi> or 
whatever the scale is. 



INTRODUCTION 27 

The drawing should always be " placed' 7 carefully, so that 
it will not be too near either side, the top, or the bottom of the 
page. Space must be reserved for the legend. The drawings 
ought not to be crowded: one on a page is usually all there is 
room for, and only one side of the paper should be used. 1 

The gross features should first be attended to, the general 
direction of the lines w T hich bound the structures, representing 
position, size, general shape, and proportions, being sketched in. 
These lines ought to be made as near right as possible without 
taking an undue amount of time. The finished drawing will be 
correct and satisfactory relatively to the accuracy of this pre- 
liminary, general sketch. 

The details, proceeding from larger to smaller, are to be 
drawn next. Usually much detail is not only unnecessary but 
even objectionable. The endeavor to get too much detail, and 
to get it without first attending to the general features, is almost 
the sole cause for the common remark, " I can't draw and never 
shall be able to!" Any one who can write can draw, and, by 
observing the right method and the proper sequence, can make 
drawings that are useful and valuable. 

The pencil should be medium soft; HB is the most useful 
grade. The lines should be drawn on, not into, the paper, and 
this requires lightness of touch. The pencil point is to be kept 
long and sharp, 2 so that it will mark readily and make a fine line 
that can be seen while it is being made. The strength (that is, 
width and blackness) of the various lines in the finished drawing 
should be proportionate to the relative importance of the struct- 
ures which they represent. The term " relative importance" 
has reference here not to anatomical or physiological value, but 
to interest in the picture : the 'things in the picture that give it 
a name are the things of greatest relative value in that picture. 

In labelling " print" the names neatly, preferably with ink. 
If there be difficulty in making the words straight and horizontal, 
light, horizontal lines may be ruled for guides ; these can after- 
wards be erased. No attempt should be made to form the letters 
exactly like printed (press) type, but a free style is to be used. 

The pointing lines, either dotted or unbroken, should be ruled 
with a sharp pencil. This differentiates them from the lines of 



1 The right side of the drawing-paper should always be used. The wrong 
side (when only one side is for use) is dimpled so as to look as if impressed 
with cotton or linen. 

2 A piece of sand-paper glued to a strip of wood is handy for this. 



28 INTRODUCTION 

the drawing. It is sometimes well to mark the exact termination 
of the line by a small cross. 

The name of the drawing in larger letters may be placed at 
the head or at the foot of the page. The view-point, scale, and 
date should also be given. Each sheet of the drawings should 
be initialed for identification, the initials being placed where 
they cannot be clipped off. 

Actual representation of an object is limited to the two dimen- 
sions of a plane. The third dimension of solid bodies is ex- 
pressed by perspective, which is made up of several factors, 
chiefly (a) binocular vision, (b) aerial perspective, (c) foreshort- 
ening, (d) sequence of objects, (e) chiaroscuro, or relation of 
light and shade. 

The part played by binocular vision is of use only in stereo- 
scopic pictures. Laboratory drawing is limited almost wholly 
to representation of things as seen by one eye. 

Foreshortening refers to apparent size and shape of objects 
(or surfaces) as dependent on position and distance. Ordinarily 
we do not take cognizance of it at all, or only partially. It may 
be made evident in several ways, as, by inverting the head and 
looking at things upside down; by looking at them in a mirror 
and regarding the images as situated on its surface ; or by inter- 
posing a transparent plane object (wire netting or glass e.g., 
window-pane) between the eye and the object, perpendicular to 
the line of vision, and regarding the lines as projected forward 
and drawn on this surface in one plane. To get a foreshortened 
drawing it is, then, only necessary to copy on paper the lines as 
thus seen; or they may be traced with crayon or India ink on 
the mirror, net, or glass itself. 

Objects that are partly hidden by nearer objects are thereby 
shown to be more distant than the latter. 

Aerial perspective, affecting color, distinctness of detail, etc., 
is of importance only when the distances are considerable, as in 
landscape, and need not be discussed here. 

The shading is self-evident. It is due to the amount of light 
reflected to the eye from the various surfaces, or areas of a sur- 
face, which have different directions, and therefore receive and 
reflect different amounts of light. For the purposes of drawing, 
the object may be regarded, and represented, as illuminated by 
light coming from a source above to the left. This simplifies 
shading and gives it a constant significance in expressing direc- 
tion of surfaces. (It is to be noted that shading can also be used, 
as in black and white pictures, to represent color-value or rela- 



INTRODUCTION 29 

tive brightness of objects of different colors.) All surfaces so 
directed as to receive and reflect most of this light to the ob- 
server's eye will be brightest (unshaded, or having " high 
lights 77 ); those directed away from the light will be darkest 
(shaded, or in shadow) ; while surfaces having an intermediate 
direction will be shaded less or more according as they approach 
one or other of the above extremes. 

A plane surface will have uniform light or shading. Rounded 
surfaces will have graduated shading ; areas separated by sharp 
edges will have abrupt differences of shading, the contrast being 
greater the smaller the angle between the adjacent areas, or, in 
other words, the greater the difference in their direction. In 
rounded objects the highest light and the deepest shade are sit- 
uated close to, but not at, the edge of the outline. All the shading 
should be kept right in relation to the deepest shadow. 

The student should examine book-illustrations and observe 
how shading is represented, (a) Some degree of depth may be 
given in a mere outline drawing by making the lines on the lower 
right side of the objects heaviest, (b) Plain parallel lines are 
used for shading in " line" drawings. The depth of shading is 
varied by the heaviness of the lines, their distance apart, and by 
" cross-hatching" or putting additional sets of shade-lines over 
the first at very acute angles of crossing. 1 (c) The pencil may 
be held obliquely and rubbed most on the parts to be shaded, 
giving a photographic effect, (d) Some of the lead of the pencil 
may be scraped off with a knife and applied to the drawing-paper 
by means of a paper stump, giving a means of rapid working, but 
one that is apt to give a smudgy effect, (e) Wash-drawings are 
shaded either by repeating the wash or by using a stronger wash 
on the shaded parts. (/) A softer pencil may be used for the 
deeper shading. Finally, it is well to " pick out" the high lights 
with a soft eraser, (g) Dots may be used instead of lines, as in 
stippled drawings, Ross-board drawings, and half-tone illus- 
trations. 

Colors may be utilized to differentiate structures, e.g., red 
for arteries, blue for veins, brown for muscles, green or orange 
(or plain black) for nerves. Good crayons are useful here. Big- 
gins 's inks of various colors may be used in pen work. Washes 
are very effective also. As a rule, all color should be used very 
sparingly, and so should shading. 

1 Sometimes the shading lines are curved in conformity to curvatures of the 
surfaces depicted, as may be seen in old wood-prints, steel engravings, and 
mechanical drawings. 



30 INTRODUCTION 

To prevent smudging of soft pencil work, the drawings may 
be " fixed" by spraying them lightly with a fixative, such as 
bleached shellac dissolved in absolute alcohol or the regular 
solution that may be obtained, together with a spray-pipe, from 
dealers in artists' supplies. 

BOOKS. 

In addition to this Laboratory Manual, the student of gross 
human anatomy is advised to provide himself with certain neces- 
sary text-books, concerning which he should consult his in- 
structor. In the University of Chicago the following are recom- 
mended : 

(1) A good atlas of the human body, preferably W. Spalteholz's " Hand 

Atlas of Human Anatomy" (Barker's translation), or C. Toldt's 
" Anatomischer Atlas." 

(2) A good systematic text-book of human anatomy, preferably (at time 

of writing) the " Systematic Text-Book of Human Anatomy" 
edited by D. J. Cunningham or Quain's " Elements of Anatomy" 
edited by Schafer and Thane. 

(3) A text-book of embryology, preferably (at present) McMurrich's 

"Human Embryology" or C. S. Minot's "Embryology" or (if 
the student can read German) J. Kollmann's " Lehrbuch der 
Entwickelungsgeschichte des Menschen." 

(4) A text-book on neurology, preferably Barker's "The Nervous Sys- 

tem and its Constituent Neurones," or Van Gehuchten's text-book 
if a French, or Obersteiner's or Edinger's if a German, author be 
desired. 

LIBKARY. 

Students beginning to study medicine often have difficulty in 
learning how to use libraries and how to find the bibliography 
of a subject in which they are interested. Each student should 
at the earliest opportunity request an instructor or a librarian 
to teach him how to use the " Index-Catalogue of the Surgeon- 
General's Library 77 and the " Index Medicus," the keys to medi- 
cal literature. For convenience, a list of some of the more 
important reference-books and journals to be consulted in con- 
nection with anatomical studies is here inserted. The student 
will find these books and journals in the college library. If any 
of them are lacking, he should use his influence to have them 
added to the library collection as soon as possible. The list is 
by no means exhaustive, but includes some of the books and 
journals likely to be frequently consulted; it does not consider 
the literature of microscopic anatomy and histology. 



INTRODUCTION 31 

General Works on Human Anatomy. 

Allen, H. A System of Human Anatomy. Including its Medical and Surgical 

Relations. 4to. Philadelphia, 1882. 

v. Bardeleben, C. Handbuch der Anatomic des Menschen. 8 vols. Jena, 1902. 
Gegenbaur, C. Lehrbuch der Anatomic des Menschen. 7 Aufl. 2 vols. 8vo. 

Leipzig, 1898. 
Gerrish, F. H. A Text-book of Anatomy by American Authors. 2d ed. Phila. 

and New York, 1902. 
Gray, H. Anatomy, Descriptive and Surgical. Ed. by T. Pickering Pick and 

R. Howden. Phila. and New York, 1901. 
Huntington, G. The Anatomy of the Human Peritoneum and Abdominal 

Cavity, considered from the Stand-point of Development and Comparative 

Anatomy. New York, 1903. 
Krause, W. Handbuch der Anatomic des Menschen, mit einem Synonymen- 

register. Auf Grundlage der neuen Baseler anatomischer Nomenklatur 

unter Mitwirkung von W. His und W. Waldeyer und unter Verweisung auf 

den Handatlas von W. Spalteholz bearbeitet. Leipzig, 1898. 
von Langer, C. Lehrbuch der systematischen und topographischen Anatomic. 

5 Aufl. 8vo. Wien und Leipzig, 1893. 
Morris, H. Human Anatomy. A Complete Systematic Treatise by Various 

Authors, including a Special Section on Surgical and Topographical Anat- 
omy. Last edition. Philadelphia. 

Poirier, P., et A. Charpy. Traite d' Anatomic humaine. 5 vols. Paris, 1901. 
Quain, J. Elements of Anatomy. Ed. by Schafer and Thane. 10th ed. 3 vols. 

London and New York, 1892. 

Rauber, A. Lehrbuch der Anatomic des Menschen. Leipzig. 
Sappey (M. P. C.). Traite d' Anatomic descriptive. 3 vols. 12mo. Paris, 

1850-1864. 
Testut, L. Traite d'Anatomie humaine. 2 vols. royal 8vo. Paris, 1889-1891. 

Anatomical Atlases. 

Anatomischer Atlas f iir Studirende und Aerzte unter Mitwirkung von Professor 

Dr. Alois Dalla Rosa. Hrsg. von Carl Toldt. Wien und Leipzig, 2 Aufl., 

1900. 
Broesike, G. Anatomischer Atlas des gesamten menschlichen Korpers. Berlin, 

1899. 

Sobotta, J. Atlas der Anatomic des menschlichen Korpers. Miinchen, 1904. 
Spalteholz, W. Hand Atlas of Human Anatomy. Translated by L. F. Barker 

from the 3d German edition. 3 vols. Leipzig, 1901-1903. 

[The descriptive text accompanying the plates of this atlas is a model 

of conciseness; some students prefer it to that of the larger systematic 

text-books.] 

Manuals of Dissection. 

v. Bischoff, Th. L. W. Fiihrer bei den Prapaririibungen bearbeitet von Dr. N. 

Ruedinger. Miinchen, 1889. 
Braune, W., and His, W. Manuel de Dissection. Trad, par le Dr. G. Foettinger. 

Svo. Bruxelles, 1887. 
Campbell, W. A. Outlines of Anatomy for Students. A Guide to Dissection, 

based on Morris's Text-book of Anatomy. Svo. Philadelphia, 1895. 



32 INTRODUCTION 

Cooke, T., and Cooke, F. G. H. Tablets of Anatomy, llth ed. 3 vols. London, 
1898. 

Cunningham, D. J. Manual of Practical Anatomy. Philadelphia and London, 
1903. 

Eckley, W. T., and Eckley, C. D. A Manual of Dissection and Practical Anat- 
omy. Philadelphia, 1903. 

Heath, C. Practical Anatomy; a Manual of Dissections. 8th ed. 12mo. Ed. 
by W. Anderson. Philadelphia, 1893. 

Holden's Anatomy. A Manual of Dissection of the Human Body. 7th ed., re- 
vised by A. Hewson. 2 vols. Philadelphia, 1901. 

Ruge, G. Anleitungen zu den Prapaririibungen an der menschlichen Leiche 
(1 und 2 Theile). 8vo. Leipzig, 1888. 

Anatomy of the Nervous System. 

Barker, L. F. The Nervous System and its Constituent Neurones. New York, 

1900. 

Bruce, A. A Topographical Atlas of the Human Spinal Cord. Edinburgh, 1901. 
Dejerine, J. Anatomic des centres nerveux. 2 vols. 1895. 
Donaldson, H. H. The Growth of the Brain. New York and London, 1895. 
Edinger, L. Anatomy of Central Nervous System of Man and of Vertebrates 

in General. Transl. by W. S. Hall. Philadelphia, 1899. 
Flatau, E. Atlas des menschlichen Gehirns und Faserverlauf . Berlin, 1899. 
v. Gehuchten, A. Anatomic du Systeme nerveux de 1'homme. 3d ed. Louvain, 

1900. 
Gordinier, H. C. The Gross and Minute Anatomy of the Central Nervous 

System. 1900. 

Hardesty, I. Neurological Technique. Chicago, 1902. 
v. Koelliker, A. Handbuch der Gewebelehre. Bd. ii. Leipzig, 1896. 
v. Lenhossek, M. Der feinere Bau des Nervensystems im Lichte neure Forsch- 

ungen. Berlin, 1895. 
Obersteiner, H. The Anatomy of the Central Nervous Organs in Health and 

in Disease. Transl. by A. Hill. London, 1900. 
Sabin, F. R. An Atlas of the Medulla and Midbrain: A Laboratory Manual. 

Edited by H. McE. Knower. Baltimore, 1901. 

Whitaker, J. R. Anatomy of the Brain and Spinal Cord. London, 1899. 
Whitehead. Anatomy of the Brain. Detroit, 1900. 
Ziehen, Th. Nervensystem, in Bardeleben's Handbuch der Anatomic des Men- 

schen. 

Surgical and Topographical Anatomy. 

v. Bardeleben, K., H. Hackel, und F. Frohse. Atlas der topographischen Anato- 
mic des Menschen. 2 Aufl. Jena, 1901. 

Deaver, J. B. Surgical Anatomy. 3 vols. Philadelphia, 1900-1903. 

Joessel, G. Lehrbuch der topographisch-chirurgischen Anatomic mit Einschluss 
der Operationsiibungen an der Leiche. Bearbeitet von W. Waldeyer. Bonn, 
1898. 

McClellan. Regional Anatomy. Philadelphia, 189 . 

Merkel, F. Handbuch der topographischen Anatomic. Braunschweig, 1898. 

Riidinger, N. Cursus der topographischen Anatomic. 4 Aufl. Miinchen, 1899. 

Treves, F. Surgical Applied Anatomy. 4th ed. London, 1889. 

Zuckerkandl, G. Atlas der topographischen Anatomic des Menschen. Wien, 
1900. 



INTRODUCTION 33 

Anatomy for Artists. 

Fritsch, G. Die Gestalt des Menschen. Stuttgart, 1899. 

Pfeiffer, L. Handbuch der angewandten Anatomic. Leipzig, 1899. 

Stratz, C. H. Die Schonheit des weiblichen Korpers. Stuttgart, 1899. 

Thompson, A. Handbook of Anatomy for Art Students. 2d ed. London, 1899. 

Comparative Anatomy of Vertebrates. 

Claus, C. Text-book of Zoology. 2d Eng. ed. London, 1890. 

Gegenbaur, C. Vergleichende Anatomic der Wirbelthiere mit Beriicksichtigung 

der Wirbellosen. Leipzig, 1898-1900. 
Jayne, H. Mammalian Anatomy as a Preparation for Human and Comparative 

Anatomy. Philadelphia, 1898. 
Parker, T. J., and W. A. Haswell. A Text-book of Zoology. 2 vols. London 

and New York, 1897. 
Wiedersheim, R. Grundriss der vergleichende Anatomic der Wirbelthiere. 

Jena, 1898. 
The Cambridge Natural History. 1895 on. 

Embryology. 

Balfour, F. M. A Treatise on Comparative Embryology. 2 vols. 1880-1881. 

Duval, M. Atlas d'Embryologie. Paris. 

Heisler, J. C. A Text-book of Embryology. Philadelphia, 1899. 

Hertwig, 0. Lehrbuch der Embryologie. 

His, W. Anatomie menschlichen Embryonen. Leipzig. 

Kollmann, J. Lehrbuch der Entwickelungsgeschichte des Menschen. 

McMurrich. Text-book of Human Embryology. Philadelphia, 1903. 

Minot, C. S. Human Embryology. New York. 

Anomalies. 

Le Double, A. Traite de variations du systeme musculaire de 1'homme et de 

leur signification au point de vue de Panthropologie zoologique. Tomes i., 

ii. Paris, 1897. 
Le Double, A. F. Traite des variations des os du crane de Phomme. Paris, 

1903. 
Testut, Leo. Les anomalies musculaires chez Phomme expliqnees par Panatomie 

comparee, leur importance en anthropologie. Paris, 1884. 

Current Literature of Gross Anatomy. 

American Journal of Anatomy. Baltimore. 

Anatomischer Anzeiger. Jena. 

Archiv fur Anatomie und Entwickelungsgeschichte. Leipzig. 

Internationale Monatschrift fur Anatomie und Physiologic. 

Jahresberichte liber die Fortschritte der Anatomie und Entwickelungsgeschichte. 
Hrsg. von G. Schwalbe. Jena. 

Journal of Anatomy and Physiology. London. 

Merkel-Bonnet's Ergebnisse der Anatomie und Entwickelungsgeschichte. Wies- 
baden. 

Zeitschrift fiir Morphologic und Anthropologie. Hrsg. von Prof. Dr. Schwalbe. 
Stuttgart. 
3 



34 INTRODUCTION 



DIVISION OF THE CADAVER INTO PAETS. 

The number of men assigned to a given cadaver and the part 
that each will dissect will vary in different laboratories, partly 
according to the supply of material, partly according to the par- 
ticular plan favored by the instructor. Very satisfactory 
methods of division have been agreed upon, among others the 
following : 

A. For ten students to a cadaver, five on each side. 

1. Arm and wall of thorax (extremitas superior). 

2. Lower extremity (extremitas inferior). 

3. Head, neck, and dorsum of trunk (caput, collum, et dorsum 

trunci). 

4. Thorax. 

5. Abdomen and pelvis (abdomen et pelvis). 

B. For six students to a cadaver, three on each side. 

1. Arm and wall of thorax (extremitas superior). 

2. Lower extremity, abdomen, and pelvis (extremitas inferior, ab- 

domen, et pelvis). 

3. Head, neck, and upper part of trunk (caput, collum, dorsum 

trunci, et thorax). 

C. For four students to a cadaver, two on each side. 

1. Upper half of body (caput, collum, dorsum trunci, thorax, et 

extremitas superior). 

2. Lower half of body (extremitas inferior, abdomen, et pelvis). 

ANATOMICAL TEEMS INDICATING THE POSITION 
AND DIRECTION OF PAETS OF THE BODY. 

In descriptive anatomy certain technical terms, derived 
chiefly from the Latin and Greek, are necessary for the desig- 
nation of parts of the body and for specifying exactly their 
spatial relations. 

In descriptions the human body is usually thought of as 
standing upright, with the arms hanging at the sides, i.e., alive ; 
the older anatomists always represented the volar surface of 
the forearm and the palm as looking forward, but at present no 
definite position in space is ascribed to the forearm. The body, 
so nearly symmetrical, is thought of as being halve'd by a per- 
pendicular plane, the so-called median (medianus) plane, into a 
right and a left half. The direction towards this median plane 
is designated as medial (medialis) ; that away from it, lateral 
(lateralis). By a vertical direction (verticalis) is meant one 
corresponding to the long axis of the median plane; a plane or 
line at right angles to the median plane, if it be parallel to the 



INTRODUCTION 35 

surface of the earth, is spoken of as being horizontal (horizon- 
tails) ; if it merely run across the body or one of its parts at 
right angles to the axis of the body, it is said to be transversal 
(transver salts). The term transverse (transversus) means 
across the long axis of the organ concerned. Lines or planes 
which run parallel to the median plane are called sagittal (sagit- 
talis) ; those parallel to the surface of the forehead, frontal 
(front alls}. 

The terms inner (internus) and outer (externus) have been 
very loosely used in English text-books, often being employed 
in the sense of medial and lateral, as well as indicating the direc- 
tion in relation to the interior of organs, cavities of the body, or 
regions of the body; in the nomenclature used in this book the 
terms are restricted exclusively to the latter meaning. In de- 
scribing the dimensions of organs length or longitudinal direc- 
tion (longitudinalis) , breadth or transverse direction (trans- 
versus), and thickness are the terms employed to indicate the 
largest, middle, and smallest dimensions. Particular attention 
is called to the distinction between transversus and transver sails, 
the latter being reserved for a direction transverse to that of 
the median plane. 

The terms upper (superior] and lower (inferior] refer to 
the directions towards the vertex and towards the sole of the 
foot respectively, while the terms superficial (superficialis) and 
deep (profundus) indicate a position of less or greater separa- 
tion from the external surface of a part or organ. The term 
middle (medius) is used to indicate a position between superior 
and inferior or between externus and internus, but, since medius 
is easily confused by the beginning student with medialis, espe- 
cially when abbreviated, the term intermediate (intermedium) is 
employed to indicate a position midway between lateralis and 
medialis. 

In order to have terms, independent of the position of the 
body in space, for the directions towards the head-end or the 
tail-end of the body, the designations cranial (cranialis) and 
caudal (caudalis) have been introduced. In the head itself the 
continuance of the cranial direction can no longer very satis- 
factorily be designated as cranial ; accordingly, this direction as 
far as the mouth or the nose is spoken of as rostral (rostmlis). 
When the body is in the upright position, the direction towards 
the front is spoken of as anterior, that towards the back as 
posterior; the same directions in the body thought of as inde- 
pendent of its position in space, are spoken of as ventral (ven- 



36 



INTRODUCTION 



trails) and dorsal (dorsalis). The adjectives right (dexter) and 
left (sinister) have their ordinary meaning. 

Besides these general terms for the body as a whole, certain 
special terms for the extremities (termini ad extremitates spec- 
t antes) are found convenient. In the extremities especially it 
is desirable to have designations independent of the position in 
space. The direction towards the trunk is, therefore, spoken of 
as proximal (proximalis) ; that away from the trunk, as distal 
(distalis). In the forearm and hand the direction towards the 
thumb side is spoken of as radial (radialis) ; that towards the 
little-finger side, as ulnar (ulnaris) ; similarly, in the leg the 
direction towards the great-toe side is spoken of as tibial (tibi- 
alis) and that towards the little-toe side as fibular (fibularis). 
Furthermore, in both upper and lower extremities, for the ex- 
tensor surfaces the expression dorsal (dorsalis) is used; while 
for the flexor surfaces the term used in the forearm and hand is 
volar (volaris) ; that in the foot, plantar (plant aris). 

GENERAL ANATOMICAL TEEMS (TERMINI 
GEN ER ALES). 

A list of certain general terms, with the English synonyms, 
employed in gross anatomy is here included. It is not intended 
that the student should begin his work by memorizing these 
words. On the contrary, he will learn them best by adding them 
gradually to his vocabulary as the dissection proceeds. 



Accessorius (accessory). 

Acinus (berry). 

Aditus (entrance). 

Ala (wing) (contraction of axilla}. 

Alveolus (little hollow). 

Ampulla (flask). 

Angulus (angle). 

Ansa (handle or loop). 

Antrum (cave). 

Apertura (opening). 

Apex (tip). 

Appendix (appendage). 

Arcus (arch). 

Area (space). 

Axilla (wing). 

Basis (base). 

Brachium (arm). 

Canaliculus (small channel). 

Canalis (canal). 

Capitulum (little head). 



Capsula (capsule). 

Caput (head). 

Cartilago (cartilage). 

Caruncula (small piece of flesh). 

Cauda (tail). 

Caverna (cavern). 

Cavum (hole or cavity). 

Cellula (little chamber or cell). 

Circulus (circle). 

Cisterna (cistern). 

Collum (neck). 

Columna (column or pillar). 

Commissura (connection or commis- 
sure). 

Cornu (horn). 

Corona (wreath, garland, or crown). 

Corpus (body). 

Corpusculum (little body or cor- 
puscle). 

Crista (crest). 



INTRODUCTION 



37 



Cms (leg or limb). 
Decussatio (decussation or crossing). 
Dorsum (back). 
Ductulus (little duct). 
Ductus (duct). 

Eminentia (eminence or protuber- 
ance). 

Endothelium (endothelium). 
Epithelium ( epithelium ) . 
Extremitas ( extremity ) . 
Facies (face or surface). 
Fascia (bandage or band). 
Fasciculus (a little bundle or packet). 
Fibra (fibre or filament). 
Fibrocartilago ( fibrocartilage ) . 
Filum (thread). 
Fissura (fissure or cleft). 
Flexura (bending). 
Folium (leaf). 
Folliculus (little sac or bag). 
Foramen (hole, aperture, opening). 
Formatio (formation). 
Fornix (arch or vault). 
Fossa (ditch or trench). 
Fossula (little fossa). 
Fovea (pit). 
Foveola (little pit). 
Frenulum (cord or rein). 
Fundus (bottom). 

Funiculus (thin rope, cord, or string). 
Geniculum (little knee or knot). 
Genu (knee). 
Glandula (gland). 
Glomerulus (little skein). 
Glomus (skein). 
Hilus (hilus). 
Humor (liquid or fluid). 
Junctura ( j oint ) . 
Impressio (impression). 
Incisura (incision or notch). 
Inf undibulum ( funnel ) . 
Intestinum (intestine or inward). 
Isthmus (isthmus). 
Labinm (lip). 
Lacuna (gap, defect). 
Lamina (plate or layer). 
Latus (broad; flank). 
Ligamentum (ligament). 
Limbus (border or fringe). 
Limen (threshold or boundary). 
Linea (line). 



Liquor (fluid or liquid). 
Lobulus (a little lobe). 
Lobus (lobe). 
Macula (spot). 
Margo (margin). 
Massa (mass). 
Meatus (way or passage). 
Medulla (marrow). 
Membrana ( membrane ) . 
Membrum (limb or member). 
Mucus (mucus). 
Musculus (muscle). 
Nervus (nerve). 
Nodulus (nodule). 
Nucleus (nucleus or kernel). 
Organon (organ). 
Orificium (orifice). 
Os, oris (mouth). 
Os, ossis (bone). 
Ostium (entrance). 
Papilla (papilla or nipple). 
P arenchy ma ( p arenchy ma ) . 
Paries (wall). 

Perichondrium ( perichondrium ) . 
Periosteum ( periosteum ) . 
Plexus (plexus). 
Plica (fold). 
Polus (pole). 
Processus (process). 
Prominentia (prominence or projec- 
tion). 

Punctum (point or small puncture). 
Radix (root). 

Ramulus (little branch or twig). 
Ramus (branch). 
Raphe (raphe or seam). 
Recessus (recess). 
Regio (region or territory). 
Rete (net or net-work). 
Rim a (slit or fissure). 
Rudimentum ( rudiment ) . 
Septulum (little septum). 
Septum (partition). 
Sinus (sinus). 
Spatium (space). 
Spina (spine or thorn). 
Stratum (layer or covering). 
Stria (furrow, stripe, or ridge). 
Stroma (stroma, orbed). 
Substantia (substance). 
Succus (juice). 



38 



INTRODUCTION 



Sulcus (sulcus or furrow). 
Tsenia (ribbon; tapeworn). 
Tegmen (a cover). 
Tela (web). 

Tela conjunctiva (connecting web). 
Tela elastica (elastic web). 
Torus (round swelling or protuber- 
ance). 

Trabecula (little beam). 
Tractus (tract). 

Trigonum (trigone or triangle). 
Trochlea (pulley). 
Truncus (trunk). 
Tuber (swelling or hump). 
Tuberculum (tubercle). 
Tubulus (tubule or little tube). 
Tunica (coat or covering). 
Tunica propria (proper coat). 



Umbo (boss or prominence). 

Uvula (little cluster or bunch). 

Vagina (sheath). 

Vallecula (crevice). 

Vallum (wall or fortification). 

Valvula (valve). 

Vas (vessel). 

Velum (sail, covering, or curtain). 

Vertex (crown of head). 

Vesica (bladder). 

Vesicula (vesicle or little bladder). 

Vestibulum (vestibule or antechamber), 

Villus (shaggy hair). 

Viscera (entrails, viscera). 

Viscus (organ, internal organ). 

Vortex (whirlpool). 

Zona (girdle or zone). 



Part I 

DISSECTION OF THE UPPER EXTREMITY 



LABORATORY MANUAL 

OF 

HUMAN ANATOMY 



UPPER EXTREMITY 

MAKE four drawings : (a) anterior view of the upper extrem- 
ity and the wall of the thorax, (b) posterior view of the same, (c) 
lateral view of the upper extremity, (d) medial view of the same. 

In the drawings show that the upper extremity (extremitas 
superior) is attached to the chest (thorax) in the clavicular and 
scapular regions. Note the prominence of the shoulder (axilla) 1 
and the projection in its upper lateral part (acromion). Con- 
tinuous with the shoulder is the rounded upper arm (brachium) ; 
beneath it, between the brachium and the thorax, is the axillary 
fossa (fossa axillaris). Draw in its anterior and posterior 
bounding folds (plica axillaris anterior, plica axillaris poste- 
rior). Show how the forearm (antibrachium) joins the brachium 
at the elbow (cubitus) ; illustrate the change in size and shape 
of the antibrachium distalward. In the drawings of the brach- 
ium label the anterior surface (fades anterior), posterior sur- 
face (fades posterior), lateral surface (fades lateralis), and 
medial surface (fades medialis), also the sulcus bidpitalis lat- 
er alls and the sulcus bidpitalis medialis; in the forearm distin- 
guish the radial side or border (mar go radialis), the ulnar side 
(mar go ulnaris), the dorsal surface (fades dorsalis), and the 
volar surface (fades volaris). 

Note how the hand (manus) is attached to the antibrachium 
by the narrower wrist (carpus). Distinguish the proximal por- 
tion of the hand (metacarpus) from the subdivided distal por- 
tion, the fingers (digiti manus). Number the digits from the 
thumb side. The thumb is the first (digitus L, or pollex), the 
index-finger is the second (digitus II., or index), the middle 

1 This is the proper usage of " axilla." In English texts it is often used as 
synonymous with " fossa axillaris." 

41 



42 LABORATORY MANUAL OF HUMAN ANATOMY 

finger is the third (digitus III., or digitus medius), the ring- 
finger is fourth (digitus IV., or digitus annularis), and the little 
finger is fifth (digitus V., or digitus minimus). Notice the rela- 
tive lengths of the digits, especially the relation of the length of 
the index-finger to that of the ring-finger. Is this constant? In 
the hand make careful drawings of the " back of the hand" 
(dorsum manus) and of the flattened " hollow of the hand" (vola 
manus, s. palma), also of the " thumb side" of the hand (mar go 
radialis) and of the " little finger side" (mar go ulnaris). In 
each digit distinguish the facies dorsalis from the facies volaris 
.and the margo radialis from the margo ulnaris. In the upper 
extremity what is meant by the " proximal direction" or a 
" proximal part"? what by the " distal direction" or a " distal 
part"! 

In the drawings of the upper part of the trunk or chest 
(thorax) show its relation to the belly (abdomen). In the back 
(dorsum) look at and feel the spines of the vertebral column 
(columna vertebralis). Number these in your drawing and pay 
especial attention to the exact level of each and the relations of 
other parts (e.g., scapula) to their levels. Designate the spine of 
vertebra C. VII. separating the neck from the back. Illustrate 
the position of the projections corresponding to the ribs (costae) 
and number them. Note especially the rib-levels of the papilla 
mammae and of various portions of the scapula when the arm is 
in different positions. Draw the breast and show the depression 
between the two breasts, the so-called bosom (sinus). Below the 
bosom, just under the sternum, indicate the flattened so-called 
" heart fossa" (scrobiculus cordis). Show the limits of the 
areola mammae about the nipple, and, if Montgomery's glands 
(glandulae areolares [Montgomerii]) are visible, picture them. 

Draw in certain lines useful in topographical anatomy : 

(1) Anterior median line (linea mediana anterior). 

(2) Posterior median line (linea mediana posterior). 

(3) Sternal line (linea sternalis), along the lateral margin of the sternum. 

(4) Mammillary line (linea mammillaris), falling perpendicularly 

through the nipple. 

(5) Parasternal line (linea par ast emails) , midway between sternal and 

mammillary lines. 

(6) Costo-articular line (linea costo-articularis) , from the sternoclavicu- 

lar articulation to the tip of the eleventh rib. 

(7) Axillary line (linea axillaris), perpendicularly from the centre of 

the fossa axillaris. 

(8) Scapular line (linea scapularis), perpendicularly through the lower 

angle of the scapula. 



Vrigonum 
~ \ deltoideopectordle 



[ ao,w.m-, i a^aoaom- VL- ^ , i \ 

inati, I / inans I \? | | M 

^G'Ml! 



/-J-l. _Vi / /k 

n v \v.jN*iix / r 

ta-. /- V" i IT /- 



SiA. H2=K /-4 -f-TW 
I VA"-""""^ / il" 

-/ iHnf^ -f-li 




-R.brachii laterali* 



--B.mbiti la!erali 



R.antil>mcKii.aor*(iHt 



R.nnMiiguinalis 

R.trocliaiiterica, 



The regions of the anterior surface of the body. ( After His, Anatomische 
Noinenclatur, Leipzig, 3895, Plate I.) 



FIG. 2. 



R.aMominalis lateralis. 



R.otecmni- 
B.cubili paste, wr 




Fossa retromnllfola 

R.rett oinalleolaris lateralis 



The regions of the posterior surface of the body. (After His, Anatomische 
Nomenclatur, Leipzig, 1895, Plate II. ) 



DISSECTION OF THE UPPER EXTREMITY 45 

Make four additional outline sketches and insert the " re- 
gions " of the upper extremity and thoracic wall, having first 
marked them out accurately with the end of the probe on the 
body. Use Figs. 1 and 2 as a guide. Ask yourself the reason 
for the name of each region. 

EEGIONS OF THE BACK (REGION ES DORSI). 

Surface Anatomy. 

In the median region of the back (regio mediana dor si) pal- 
pate the spinous processes (processus spinosi) of the vertebrae. 
Are they all in one plane ? Find the spine of the seventh cervical 
vertebra (vertebra prominens). Are any other spines especially 
noticeable? Enumerate the spines consecutively. Is there any 
marked kyphosis, lordosis, or scoliosis present? 1 Palpate the 
scapula and ascertain its general outline. Move the arm in 
various directions and note accompanying changes in position 
of scapula. With the arm of the cadaver by the side, establish 
the spinal level and the rib-level of the angulus medialis and 
of the angulus inferior of the scapula. Run the finger along the 
spina scapulae and the acromion and note that both are subcu- 
taneous. Establish exactly the bony point corresponding to the 
junction of the lower border of the spina scapulae with the lat- 
eral margin of the acromion. ( Surgeons measure the arm from 
this point, the tape being carried down to the epicondylus later- 
alis of the humerus.) 

Superficial Structures. 

Make skin incisions (1) along the linea mediana posterior 
from the vertebra prominens to the tip of the coccyx, (2) from 
the tip of the coccyx to the posterior superior iliac spine, then 
along the crista iliaca to near the anterior superior iliac spine, 
(3) from the vertebra prominens to the medial edge of the 
acromion, and (4) from the processus spinosus vertebrae 
Jumbal is I. to the lateral margin of the acromion. Reflect the 
two triangular flaps of skin, taking none of the fat of the 
superficial fascia with it. Have your atlases open before you. 
Having ascertained the region in which tlie medial set of cuta- 
neous vessels and nerves is likely to be found, witli the knife 
make a small cut through the superficial fascia down to the deep 

1 When a word is met with in this manual (or in any text-book) which is 
new to the student, he should look up its meaning at once in a good medical 
dictionary. 



46 



LABORATORY MANUAL OF HUMAN ANATOMY 



FIG. 3. 



fascia. With the special heavy probe recommended, separate an 
area of the superficial fascia until you encounter the trunk of a 
blood-vessel or a nerve coming through the deep fascia from 
below to enter the superficial fascia. It is common to find a 
nerve, an artery, and a vein together. Carefully separate the 
structure or structures found from the superficial fascia, tracing 

the blood-vessel or nerve as far 
as possible and cleaning it thor- 
oughly. In this way, isolate all 
the superficial blood-vessels and 
nerves in the medial and lateral 
areas in which they occur. The 
nerves and blood-vessels will be 
found emerging through the 
deep fascia. Their course and 
ramifications in the superficial 
fascia are to be traced out with- 
out removing the fat or disturb- 
ing the relations of the struct- 
ures any more than is necessary 
in exposing them. It should be 
borne in mind that it is only the 
natural relations that are of im- 
portance, and not the artificial 
relations due to dissection. 
Hence each structure should be 
studied as it is worked out, in- 
stead of its study being deferred 
until after it is isolated and 
cleaned. When the cutaneous 
nerves and vessels and superfi- 
cial glands have been thus ex- 
posed, a drawing of these should 
be made ; or the drawing may be 
made concurrently with the dissection, being then an aid to the 
determination of the exact relations. 

The deep fascia should be cleaned (by careful removal of the 
superficial fascia by blunt dissection) and its extent, nature, and 
attachments studied. The fasciae should then be removed piece- 
meal. In cleaning the surface of the muscles, place the body in 
such a position that the muscle-fibres will be rendered tense and 
carry the knife in the direction which permits removal of the 
fascia with the least disturbance of the underlying muscle. Care 




Skin incisions on the posterior surfaces of the body. 



DISSECTION OF THE UPPER EXTREMITY 



47 



FIG. 4. 



M. scmiitpinaliti capitis (turned back) 
Jf. rt'ctuft capifin ]ni.<tf rinr major 

AT obliquus capitis superior.^ 
N. suboccipitalis. 

Arcus posterior atlanti*^ 

M. obliquus capitis inferior -Ng 
Ramus posterior N. cervicalis II.,- 

J/. scmispinalis capitis.. //. 

i'-'/A 

M. splcnius cervicis __ 
J/. levator scapulae.. _ 
N. dorsalisscapulae__.. 

Jfin. 

rhoiaboidci 



Lateral 

branches of the 
rami posteriores 
Nn. thoracalium 



Medial branches of -*- 
the rami posteriores 
Nn. thoracalium 

J/. longissimus dorsi,- 



31. HiocontaUs dorsi.^ 

Ramns posterior N. 
thoracalis XII. 
M. multifidus 

Ramus posterior < - 
N. lumbalis I. 



Nn, clunium superiores 



Rami posteriores ^^ 
Nn. sacralium 



N. occipitalis major 
M. trapezius 
M. splenius capitis (laid back) 

N. occipitalis tertius (Var.) 

-N. occipitalis minor 

M. semispinalis 

Rami cutanei dorsales 
Nn. cervicalium V., VI. 

Ramus cutaneus dorsalis 
N. thoracalis I. 




Rami posteriores of the 
rami cutanei laterales 

Nn. intercostalium 
Rami cutanei dorsales from 
the rami posteriores Nn 
thoracalium (medial and 
lateral branches) 
Fascia superflcialis 

Fascia lumbodorsalis 

- ; Rami cutanei dorsales from 

/'the posterior branch of the 

N. thoracalis XII. 



Rami cutanei dorsales 
Nn. lumbalium 



\ Nn. clunium superiores 
V V. (rami cutanei from the 
posterior branches of 
the Nn. lumbales I., 
IT., III.) 
Tubcrositas iliaca 



The distribution of the posterior branches, rami posteriores, of the spinal nerves, Nn. spinales. 
(On the right side of the body the cutaneous branches are shown ; on the left side, the muscle-branches ; 
and in part the course of the posterior branches of these are shown.) (After Toldt, Anat. Atlas, Wien, 
1903, 3 Aufl., p. 813, Fig. 1245.) 



48 LABORATORY MANUAL OF HUMAN ANATOMY 

should be taken to avoid giving a " ragged " appearance to the 
surface of the muscle. As soon as the trunk of a nerve or blood- 
vessel is found, ascertain its name from a study of the illustra- 
tion in your atlas. Look up this name in the index to your Sys- 
tematic Human Anatomy and refer to the author's description. 
When handling a nerve, blood-vessel, or indeed any structure, 
form the habit of repeating to yourself its name ; this practice 
is extremely helpful in fixing the association between the struct- 
ure and the name which is the sign for it. Also, when reading 
write down every new term met with and learn its meaning, both 
literal or etymological and applied or derived. 

Nerves. (Fig. 4.) 

(a) Cutaneous branches of posterior rami of thoracic nerves (rami 

cutanei Rr. post. Nn. thoracalium). 

(b) Posterior rami of lateral cutaneous rami of anterior rami of inter- 

costal nerves (rami posteriores Rr. cutan. lat. Rr. ant. Nn. inter- 
costalium). 

(c) Medial rami of posterior rami of lumbar, sacral, and coccygeal 

nerves (rami mediales Rr. post. Nn. lumb., sacral., et coccyg.}. 

(d) Lateral rami of posterior rami of lumbar nerves (rami laterales 

Rr. post. Nn. lumbalium = Nn. clunium superiores). 
Arteries. 

(a) Medial cutaneous rami of posterior rami of intercostal arteries 

(rami cutanei mediales Rr. post. Aa. intercostalium) . 

(b) Lateral cutaneous rami of posterior rami of intercostal arteries 

(rami cutanei laterales Rr. post. Aa. intercostalium). 

(c) Dorsal cutaneous rami of lumbar arteries (rami cutanei dorsales 

Aa. lumbalium). 

(d) Posterior rami of lateral cutaneous rami of anterior rami of inter- 

costal arteries (rami posteriores Rr. cutan. lat. Rr. ant. Aa. 
intercostalium) . 
Veins. (Cf. Toldt, Fig. 1036.) 

(a) Dorsal rami of intercostal veins (rami dorsales Vv. intercostalium). 

(b) Branches of lumbar veins (Vv. lumbales). 

Broad Muscles of the Back (First Layer). (Fig. 5.) 

(a) Trapezius muscle (M. trapezius}. 

(b) Broadest muscle of back (M. latissimus dorsi). 

Study the form and position of each, and establish its exact 
origin and insertion. Test the action of the fibres of the different 
parts of the muscles. Find their innervation now or later. To 
what other structures are these muscles related! Examine the 
boundaries and floor of the " triangle of auscultation." Why 
is it so called! Examine the boundaries and floor of Petit 's 
triangle (trigonum lumbale [Petiti]). 



DISSECTION OF THE UPPER EXTREMITY 



49 



FIG. 5. 



M. auricularis superior 
M. auricularis posterior ~- 
M. transversus nuchae ( Var. ) ___ 
M. semispinalis capitis 

M. sternocleidomastoideus' 
M. splenius capitis 



i"'M. occipitalis 




M. triceps M. teres 
brachii major 
(caput 

longum) 



obliquus externus 
abdominis 



Spina 
scapulae 



. triceps brachii 



Vertebra thoracalis XII. 



M. obliquus 
externus abdominis 

Trigonum lumbale (Petiti) 
Crista iliaca 



r -Spina iliaca posterior 
superior 



Fascia glutaea^ pi 



First (superficial) layer of the broad muscles of the back. ( After Toldt, Anat. Atlas, 
Wien, 1900, 2 Aufl., p. 266, Fig. 504.) 



50 



LABORATORY MANUAL OF HUMAN ANATOMY 



Cut through the M. trapezius by a vertical incision five centi- 
metres later alward from the median plane, avoiding injury to 
the muscles of the second layer. Dissect out, on its deep surface, 
the following structures : 

FIG. 6. 



Processus costarius vertebrae lumbalis IV. 

M. iliocostalis 
Fascia lumbodorsalis 
Ligamentum lumbocostale 



M. longissimus 

M. multifidus 



M. quadratus lumborum 



Adipose tissue 



Processus spinosus 
i verebrae 

:ra> lumbalis III. 



Fascia transversalis 



M. latissimus 
dorsi 



Upper surface of the 
vertebra lumbalis 
IV. 




M. transversus abdominis 
M . obliquus interims abdominis i 
M. obliquus externus abdominis 



Fascia superficial^ 
Integumentum commune 

M. rectus abdominis 



Linea alba 



: : Umbilicus 

Lamina anterior Lamina posterior 
Vagina M. recti abdominis 

The muscles and fasciae in a transverse section of the right half of the wall of the trunk. 
(After Toldt, Anat. Atlas, Wien, 1900, 2 AufL, p. 281, Fig. 520. ) 

(a) External ramus of accessory nerve (ramus externus N. accessorii). 

(b) Muscular rami from cervical nerves (rami muscular es Nn. cervica- 

lium). 



DISSECTION OF THE UPPER EXTREMITY 51 

Broad Muscles of the Back (Second Layer). 

Make the rhomboid muscles tense and clean their surfaces 
carefully. Find the trunk of the dorsal nerve of the scapula 
(A 7 , dor sails scapulae] (O. T.. nerve to the rhomboids) and the 
descending ramus of the transverse artery of the neck (A. trans- 
versa colli) in the interval between the M. levator scapulae and 
the M. rhomboideus minor. 

(a) Greater rhomboid muscle (M. rhomboideus major). 

(b) Lesser rhomboid muscle (M. rhomboideus minor). 

(c) Levator muscle of scapula (M. levator scapulae) (0. T. levator anguli 

scapulae). 

Establish the form, position, origin, insertion, action, and 
innervation of each. Find the two rami of the cervical nerve on 
the surface of the M. levator scapulae and then cut the muscle in 
two in the middle. Eeflect the lower portion lateralward. Cut 
through the attachments of the Mm. rhomboidei near the median 
plane and reflect the muscles lateralward. Dissect out care- 
fully- 

(a) Dorsal nerve of scapula (N. dorsalis scapulae). 

(b) Descending ramus of transverse artery of neck (ramus descendens 

A. transversae colli) (0. T. posterior scapular artery). 

Near the superior margin of the scapula expose the inferior 
belly of the omohyoid muscle (venter inferior M. omoliyoidei}. 
Define its exact attachment to the scapula. Note the relations 
of the A. transversa scapulae (0. T. suprascapular artery) and 
of the N. suprascapularis to the Lig. transversum scapulae 
superius. 

The dissector of the arm may next assist the dissector of the 
head in making out the muscles of the back. Study the form, 
position, origin, insertion, action, and innervation of each. 



ANTERIOR THORACIC REGION AND AXILLARY 

FOSSA. 

Surface Anatomy. 
Examine 

(a) Outline of clavicle. 

(aa) Shaft of clavicle. 

(ab) Sternal extremity (extremitas sternalis). 

(ac) Acromial extremity (extremitas acromialis). 



52 LABORATORY MANUAL OF HUMAN ANATOMY 

Compare the distance between the acromion and the ster- 
nal extremity of the clavicle on the two sides. Why would 
such a comparison be of importance in surgical diagnosis? 

(b) Outline of sternum. 

(ba) Manubrium sterni. 

Jugular notch (incisura jugularis) (0. T. suprasternal 
notch). 

(bb) Corpus sterni (0. T. gladiolus). 

Angle of sternum (angulus sterni) (0. T. angulus Ludovici, 
angle of Louis), an important landmark in counting ribs 
and intercostal spaces. 
(be) Processus xiphoideus (0. T. ensiform process). 

(c) Costal arches I -XII. 

(ca) Ribs (costae I.-XIL). 

(cb) Costal cartilages (cartilagines costales). 

Is a " rickety rosary" present ? 

(d) Coracoid process of scapula (processus coracoideus scapulae). Note 

its relation to the infraclavicular fossa (fossa infraclavicularis or 
Mohrenheim's fossa) and the relation of the clavicular origins of 
the M. pectoralis major and the M. deltoideus to the latter. 

(e) Breast (mamma). 

(ea) Papilla mammae, or nipple of the breast. 

Note its exact level and its distance from the anterior 
median line. 

(eb) Body of breast (corpus mammae). 

Note its dimensions. 

(ec) Areola mammae. 

(1) Sebaceous glands (Gl. sebaceae). 

(2) Areolar glands (Gl. areolares [Montgomerii]). 

(ed) Accessory breasts (mammae accessoriae) . 

Are any present? What is the direction of the so-called 
" milk-line" ? Note that of the two rows of milk-glands 
running from the forelimb to the inguinal fold, the head- 
ward portions are preserved in primates, the tailward por- 
tions in ruminants. What are meant by the terms poly- 
mastism, polythelism , and atavism? 

(f) Boundaries of axillary fossa (upper extremity abducted). 

(fa) Anterior axillary fold (plica axillaris anterior). 

To what is it due? 

(fb) Posterior axillary fold (plica axillaris posterior). 

To what is it due? Which fold extends to the lower 
level ? 

(g) Upper extremity of humerus. 

Palpate, in the axillary fossa, the medial surface of the surgical 
neck (collum chirurgicum) and feel the head of the humerus (caput 
humeri) rotate when the arm is rotated. 

Skin and Superficial Fascia, with Vessels and Nerves. 

Make the following incisions in the skin (cf. Fig. 7) : 

(a) In the linea mediana anterior from the fossa jugularis to the tip of 
the processus xiphoideus. 



DISSECTION OF THE UPPER EXTREMITY 



53 



(b) From the processus xiphoideus lateralward to the back. 

(c) From the upper end of the first incision lateralward along the clavicle 

to the tip of the acromion. 

(d) From the processus xiphoideus obliquely upward and lateralward 

along the plica axillaris anterior as far as the brachium. 



FlG. 7. 



With a sharp knife dissect up the two triangular flaps marked 
out by the incisions mentioned. Keep the knife close to the white 
corium so that none of the fat 
of the superficial fascia is re- 
moved with the skin. 

Compare the amount of fat 
in the superficial fascia in your 
subject with that in neighboring 
subjects. Find the fibres of the 
platysma streaming down into it 
over the clavicle. Note that the 
mammary gland is situated in 
the superficial fascia. Cut boldly 
through the superficial fascia 
down to the deep fascia in the 
middle line in front, and then 
with the blunt probe dissect up 
the superficial fascia, passing 
gradually lateralward. Find the 
cutaneous blood-vessels and 
nerves passing into the super- 
ficial fascia from the depth. 
When the trunks of these are 
found, follow each carefully out 
as far as possible into the super- 
ficial fascia, cleaning it care- 
fully. Avoid injury to the 
superficial nerves which pass 
down over the clavicle. Keep 
your atlases open before you as 
a guide to the location of the various structures. As soon as 
a nerve or blood-vessel is found, identify it, getting the name 
from the atlas. Find a description of it in your systematic 
text-book of anatomy (using the index of the latter) and com- 
pare the actual findings in your subject with the text-book de- 
scription. Note especially any differences between your object- 
ive findings and the printed descriptions. 




Skin incisions on the anterior surfaces of the body 



54 



LABORATORY MANUAL OF HUMAN ANATOMY 



Ramus cutaneus anterior of the 
N. intercostalis I. \ 



Rarmis cutaneus 
lateralis (pecto- 
ralis) of the N. 
intercostalis VI. 



Rami musculares 
of the N. intercostalis I. 



Mm. intcrcostales externi 
M. intercostalis interims 

Fascia endothoracica 
__N. intercostalis IV. 



Fascia endo- 
thoracica 



N. intercostalis 

VII. 
Ramus 
muscularis 




Ramus cutaneus ante- 
rior (abdominalis) of 
the N. intercostalis 
IX. 

Ramus cutaneus later- 
alis (ramus anterior) 
of the N. intercosta- 
lis XII. 



Ramus cutaneus 
anterior of the 
N. intercosta- 
lis XII. 

Ramus cutaneus 
anterior of the 
N.iliohypogas- 
tricus 



N. ilioinguinal 



. oil/quits 
internus 

abdomini* 
._. M. transvcrsus 



N. intercostalis 
XII. 



Rami musculares 



Ramus muscu- 
laris of the N. 
ilioinguinalis 

...N. ilioin- 
guinalis 



,,N. spermaticus 
externus 



The cutaneous nerves of the anterior side of the trunk. (After Toldt, Anat. Atlas, Wien, 1903, 

3 Aufl., p. 814, Fig. 1246. ) 



DISSECTION OF THE UPPER EXTREMITY 55 

Study the following: 

Superficial Nerves. (Fig. 8.) 

(a) Supraclavicular nerves (Nn. supraclaviculares) (0. T. descending 

cutaneous nerves). 

(aa) Anterior (Nn. supraclaviculares anteriores) (0. T. supra- 

sternal branches). 

(ab) Middle (Nn. supraclaviculares medii) (0. T. supraclavicu- 

lar branches). 

(ac) Posterior (Nn. supraclaviculares posteriores) (0. T. supra- 

acromial branches). 

What are their relations to the platysma? 

(b) Anterior cutaneous rami of the intercostal nerves (rami cutanei 

anteriores Nn. intercostalium). 
(ba) Medial mammary rami (rami mam marii mediales). 

(c) Lateral cutaneous rami of the intercostal nerves (rami cutanei lat- 

erales Nn. intercostalium), dividing beneath the M. ser- 
ratus magnus into 

(ca) Posterior rami (rami posteriores). 

(cb) Anterior rami (rami anteriores). 

Note that the latter give off the lateral mammary rami 
(rami mammarii laterales). 
Arteries. (Fig. 9.) 

(a) Perforating rami of internal mammary artery (rami perforantes 

A. mammarii internae). 

(aa) Mammary rami (rami mammarii). 

(ab) Muscular rami (rami musculares). 

(ac) Cutaneous rami (rami cutanei). 

(b) Anterior cutaneous rami of anterior rami of intercostal arteries 

(Rr. cutanei anteriores Er. ant. Aa. intercostalium), in 
fourth and sixth intercostal spaces only. 
(ba) Medial mammary rami (Er. mammarii mediales). 

(c) Lateral cutaneous rami of anterior rami of intercostal arteries (Er. 

cutanei laterales Er. ant. Aa. intercostalium). 

(ca) Posterior ramus (ramus posterior). 

(cb) Anterior ramus (ramus anterior). 

(cba) Lateral mammary' rami (Er. mammarii laterales). 

(d) Lateral thoracic artery (A. thoracalis lateralis). 

(da) External mammary rami (Er. mammarii externi). 
Veins. 

Tributaries of the axillary vein. 

(a) Lateral thoracic vein (V. thoracalis lateralis). 

(b) Thoraco-epigastric vein (V. thoraco-epigastrica) , receiving many 

of the Vv. cutaneae pectoris. 
Tributaries of the V. anonyma. 

(a) Tributaries of internal mammary vein. 

(aa) Perforating rami (rami perforantes). 

(ab) Intercostal veins (Vv. intercostales) (sternal extremi- 

ties). 
Tributaries of V. azygos. 

(a) Tributaries of intercostal veins (vertebralward). 

(aa) Cutaneous veins of chest (Vv. cutaneae pectoris). 



56 



LABORATORY MANUAL OF HUMAN ANATOMY 



FIG. 9. 



A. cervicalis superficial! 
A. transversa colli (arising abnormally) \ 
A. transversa scapulae 



A. subclavia dextra 

Ramus costalis lateralis (Var.) 
^ A. mammaria interna 
Rami perforantes 
Kami cutanei 




M. obli- 
quus 



A. epigastrica inferior 



A. circumflexa ilium 
profunda 

A. circumflexa ilium - 
superficialis 



A. lig. teretis uteri 

A. femoralis 

V. femoralis 
Aa. labiales anteriores/ 



Lymphoglandu- 
lae inguinal es 



Lymphoglandu- 

lae subinguinales 

superficiales 



V. saphena magna 
Aa. pudendae externae 



Arteries of the anterior body-wall. (After Toldt, Anat. Atlas, Wien, 1903, 3 AufL, p. 581, Fig. 957.) 



DISSECTION OF THE UPPER EXTREMITY 57 

Mammary Gland (Mamma). (Fig. 10.) 

Compare the gland in your subject with one from a subject 
of the opposite sex. If the breast is well developed, dissect the 
gland under water and make out 

(a) Lobes of breast (lobi mammae). 

(aa) Lobules of breast (lobuli mammae). 

(b) Milk-ducts (ductus lactiferi). 

(ba) Milk-sinuses or ampullae (sinus lactiferi). 



FIG. 10. 




Medial margin 
Fascia pectoralis- - 
M. pectoralis major ^ 
Pannicidus adiposus,^ 
Integument um commune,- 
Lobuli mammae >; 
Lobi mammae's;-' 

Papilla mammae^ 



Ductus lactiferi 

Sinus lactiferi 

Corpus mammae 

Lateral margin 
Horizontal cut through the female breast. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 501, Fig. 860.) 

Review the blood-supply of the mamma. Study illustrations 
of the lymphatic channels leading from the breast to the pectoral 
lymph-glands (lymphoglandulae pectorales), the axillary lymph- 
glands (lymphoglandulae axillares), and the sternal lymph- 
glands (lymphoglandulae sternales). (Cf. Figs. 15, 86, and 93.) 
Note that where the breasts are very large the lymphatic chan- 
nels of one breast may communicate with those of the breast of 
the opposite side across the median line. 

Fascia Pectoralis or Deep Fascia. 

Note its relations above, below, medialward, and lateralward, 
a.nd the process from it to the fascia coracoclavicularis in the 
fossa infraclavicularis. 



58 LABORATORY MANUAL OF HUMAN ANATOMY 

Greater Pectoral Muscle (M. pectoralis major). 

Make the muscle tense by abducting the upper extremity. 
Remove the fascia pectoralis from its surface and the deltoid 
portion of the fascia brachii from the anterior margin of the 
M. deltoideus. Stop at the plica axillaris anterior before reach- 
ing the fascia axillaris. Avoid injury to the vena cephalica and 
the acromial ramus of the arteria thoraco-acromialis (0. T. 
humeral thoracic artery). 

FIG. 11. 







Insertion of 
pectoralis 




Intermediate 
entopectoral 

slip 



Pectoralis 
minor 



M. pectoralis major with deficiency of sternocostal portion, and resulting production of an atypical 
displaced intermediate pectoral muscle (M. tensor semivaginae articulationis humero-scapularis, Gruber, 
M. pectoralis minimus). Adult human subject. From a fresh dissection. (After G. S. Huntington, 
Amer. Jour, of Anat., Baltimore, 1903, vol. ii., No. 2, Plate I., Fig. 1. ) 

Note in connection with the M. pectoralis major 

(a) Its form. 
(&) Its position. 



DISSECTION OF THE UPPER EXTREMITY 



59 



(c) Its origin. 

(ca) Pars clavicularis. 

(cb) Pars sternocostalis. 

(cc) Pars abdominalis. 

(d) Its insertion. 

(e) Its innervation (Nn. thoracales anterior es]. 

(f) The bursa M. pectoralis majoris. 

Look up an article upon the torsion of the tendon of this muscle 
by Dr. Warren Lewis, in the American Journal of Anatomy. 

FIG. 12. 



..Brachial arch 



Axillary arch 




The brachial and axillary arches. (From Poirier et Charpy, 
Traite d'Anat. hum., Paris, 1901, 2 ed., p. 164, Fig. 126.) 

Axillary Fascia (Fascia axillaris). (Figs. 12 and 13.) 

Carefully remove the superficial fascia over the base of the 
axillary fossa so as to expose the deep or axillary fascia. 
Note- 

(a) An apparent oval opening between the concave aponeurotic bands; 
the lower lateral concave band is the brachial arch (Armbogen of 
Langer) ; the upper medial concave band is the axillary arch 
(Achselbogen of Langer). If the dissection be made very care- 
fully, a delicate, much-perforated membrane can be made out, ex- 
tending from the brachial arch to the axillary arch, so that the 
bundle of vessels and nerves seen through the oval opening is not 
really subcutaneous. (Poirier.) Note the striking resemblance of 



60 



LABORATORY MANUAL OF HUMAN ANATOMY 



this oval opening to the fossa ovalis of the thigh, of the thin mem- 
brane covering it to the cribriform fascia, of the axillary arch to 
the cornu superius of the margo falciformis, and of the brachial 
arch to the cornu inferius of the margo falciformis. 

(6) The continuity of the fascia axillaris lateralward with the fascia 
brachii and with the fascia enclosing the M. latissimus dorsi and 
Mm. teretes major et minor; it becomes inserted into the axillary 
margin of the scapula. 

(c) The continuity of the fascia axillaris medialward, not with the fascia 
pectoralis, but with the fascia coracoclavicularis, which encloses the 
M. pectoralis minor. (Fig. 13.) The membrane extending from 
the axillary fascia to the lower bolder of the M. pectoralis minor 
was formerly called the suspensory ligament of the axilla (ligament 
suspenseur of Gerdy). 



FIG. 13. 



M. subscap- 



Bundle of nerves and vessels.... 



M. teres min. 

M. teres maj . 

M. lat. dorsi 




-.-.Clavicula 
M. subclav. 

....Fascia coracoclav. 



-M. pect. min. 

M. pect. maj. 
Axillary arch 



Sagittal section of the axillary fossa. (Very schematic.) (From Poirier et Charpy, Trait< d'Anat. 
hum., Paris, 1901, t. ii. p. 165, Fig. 128.) 

(d) The passage through the oval opening (and the cribriform fascia 

covering it) of the intercostobrachial nerves (Nn. intercosto- 
brachiales) (0. T. intercostohumeral nerves). These represent the 
lateral cutaneous rami of the second and third intercostal nerves 
(rami cutanei laterales Nn. inter cost alium II. et III.}. It is inter- 
esting that the vena basilica may occasionally bear the same rela- 
tion to the oval opening that the vena saphena magna bears to the 
fossa ovalis in the thigh; the usual condition, however, is for the 
V. basilica to pass beneath the deep fascia a little above the elbow. 

(e) Later in the dissection, the reflections of the axillary fascia upon the 

arteries and nerves going to the forearm. 

Structures in the Fossa Axillaris. (See Figs. 14, 15, and 16.) 

The fascia axillaris may now be reflected backward, care 
-being taken to dissect out carefully the intercostobrachial nerves. 
The structures in the axillary fossa are to be isolated and 



DISSECTION OF THE UPPER EXTREMITY 



61 



cleaned, the loose areolar tissue and fat in which they are era- 
bedded being gradually removed. Secure first the subscapular 
artery and the thoracodorsal nerve along the lower border of 
the M. subscapularis, then the lateral thoracic artery (lower 
border of M. pectoralis minor), next the long thoracic nerve 
(lying on M. serratus magnus). The various lymph-glands are 

FIG. 14. 



coracobrach. et biceps (cap. breve) 

T*. cephalica 

\ Tendon of M. lat. dorsi 

Tendon of caput longum 
\ ; / M. bicipitis 

M. deltoideus 



r M. teres major 
Humerus 




: V. A. circ. post. 

N. axillaris 
M. teres min. 

M. triceps (cap. long.) 
Corpus scapulae 

Cross-section of the shoulder above the origin of the circumflex arteries, right side, segment distal 
to the cut. Subject fixed in formalin chromic acid. The fat over the V. and A. circumflex posterior 
and the N. axillaris has been removed to show the course of these structures. The N. radialis is seen 
medial to the N. axillaris. The N. ulnaris lies anterior to the N. radialis. The two heads of the 
median have just united and the N. musculocutaneus is separating off. (After Poirier et Charpy, Traite" 
d'Anat. hum., Paris, 1901, 2 ed., t. ii. p. 93, Fig. 87.) 

to be studied carefully as they are exposed and may afterwards 
be removed. The following structures are to be isolated and 
studied, some of them being best seen after the dissection of the 
M. pectoralis minor and the fascia coracoclavicularis. 

Lymphatic Glands. (Cf. Figs. 15, 86, and 93.) 

(a) Axillary lymph-glands (lymphoglandulae axillares}. 

(b) Pectoral lymph-glands (lymphoglandulae pectorales). 



62 LABORATORY MANUAL OF HUMAN ANATOMY 

FIG. 15. 



Lymphoglandulae 

axillares 



V. cephalica 



Lymphoglandulae 
cubitales 
superficiales 




Lymphatics of the arm and of the anterior and lateral sides of the thorax. 
(From Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 704, Fig. 1086.) 



DISSECTION OF THE UPPER EXTREMITY 



63 



(c) Subscapular lymph-glands (lymphoglandulae sub scapular es) . 

Count the number of lymph-glands found in each of these 
three chains. Whence do the glands of each of these three chains 
draw lymph? Note especially the intimate relations of the 
glands of the middle chain to the axillary vein. 



FIG. 16. 

Tmncus thyreocervicalis 

Jf. scalenus anterior '; 

transversa scapulae ; ; 

cransversa colli : : - ; 



Ramus subclavius 

A. axillaris 
f Ramus pectoralis 

A. thoracoacromialis j Ramus acromialis "' 
I Ramus deltoiden 



A . vertebralis 

: : A. mam TD aria interna 
: A. subclavia 
/ / A. anonyma 
: 



N. medianus 



A. circumflexa I 



anterior 



humeri [posterior 




A. thoracalis lateralis 



The subclavian and the axillary artery and their relation to the plexus brachialis. 
(After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. G10, Fig. 986.) 

Arteries. (Fig. 16.) 

(a) Axillary artery (A. axillaris). 

(aa) Highest thoracic artery (A. thoracalis suprema) (0. T. 
superior thoracic artery). 



64 LABORATORY MANUAL OF HUMAN ANATOMY 

(ab) Thoraco-acromial artery (A. thoraco-acromialis) (0. T. 

acromiothoracic or thoracic axis). 

(ac) Lateral thoracic artery (A. thoracalis lateralis) (0. T. long 

thoracic). 
(aca) External mammary rami (Er. mammarii externi). 

(ad) Subscapular artery (A. sub scapular is). 

(ada) Thoracodorsal artery (A. thoracodorsalis) . 

(adb) Circumflex artery of scapula (A. circumflexa 

scapulae) (0. T. dorsalis scapulae). 

(ae) Anterior circumflex artery of humerus (A. circumflexa 

humeri anterior). 

(af) Posterior circumflex artery of humerus (A. circumflexa 

humeri posterior) . 
Veins. 

(a) Axillary vein (V. axillaris). (Spalteholz, Fig. 492.) 

(aa) Lateral thoracic vein (V. thoracalis lateralis}. 

(aaa) Thoraco-epigastric vein (V. thoraco-epigastrica). 

(aab) Costo-axillary veins (Vv. costo-axillares). 

(ab) Brachial veins (Vv. brachiales). 

(ac) Cephalic vein (V. cephalica). 

(aca) Thoraco-acromial vein (V. thoraco-acromialis). 

(ad) Other tributaries corresponding to branches of axillary 

artery. 
Nerves. 

At this stage of the dissection the relation of a group of nerves 
to the A. axillaris should be closely observed, the full study of the 
brachial plexus and its branches being made a little later. Note 
then the relations of 

(a) Ulnar nerve (N. ulnaris). 

(b) Medial cutaneous nerve of upper arm (N. cutaneus brachii me- 

dialis) (0. T. lesser internal cutaneous, or nerve of Wrisberg). 

(c) Medial cutaneous nerve of forearm (N. cutaneus antibrachii me- 

dialis) (0. T. internal cutaneous). 

(d) Radial nerve (N. radialis) (0. T. musculospiral). 

(e) Axillary nerve (N. axillaris) (0. T. circumflex). 
(/) Median nerve (N. medianus), with its two heads. 
(g) Musculocutaneous nerve (N, musculocutaneus) . 

Shape and Boundaries of Fossa Axillaris. 

Describe the form of the fossa. What is the position of its 
apex? How many walls has it? What structures help to form 
the anterior wall ? What structures enter into the formation of 
the posterior wall? Examine carefully the structures consti- 
tuting respectively the medial and lateral walls of the fossa. 

Coracoclavicular Fascia (Fascia coracoclavicularis). 

Divide the pars clavicularis of the M. pectoralis major close 
to the clavicle (leaving the pars sternocostalis for the present 
intact) and reflect it downward and lateral ward, avoiding injury 



DISSECTION OF THE UPPER EXTREMITY 65 

to the vessels and nerves beneath. The coracoclavicular fascia 
is now exposed. What are its attachments? How does it form 
a sheath for the M. subclavius ? Divide the anterior layer of the 
sheath transversely close to the clavicle and expose the M. sub- 
clavius ; observe the N. subclavius entering the deep surface of 
the latter ; with the handle of the scalpel demonstrate the attach- 
ment of the posterior layer of the sheath behind the muscle. 
The portion of the fascia extending between the clavicle and the 
M. pectoralis minor is often called the " costocoracoid mem- 
brane. ' ' Piercing this portion of the fascia find the following : 

(a) Acromiothoracic artery (A. acromiothoracalis) (0. T. thoracic axis). 

(aa) Acromial ramus (ramus acromialis) . 

(ab) Acromial network (rete acromiale). 

(ac) Deltoid ramus (E. deltoideus) (0. T. humeral branch). 

(ad) Pectoral rami (Rr. pectorales). 

(b) Acromiothoracic vein (V. acromiothoracalis}. 

(c) Cephalic vein (V. cephalica). 

(d) Lateral anterior thoracic nerve (N. thoracalis anterior lateralis). 

Divide the pars sternocostalis of the M. pectoralis major 
about its middle and reflect it lateralward and medialward. Pre- 
serve the branches of the anterior thoracic nerves entering the 
deep surface of the muscle ; some of them have already passed 
through the M. pectoralis minor. 

Note that the sheath of the M. pectoralis minor is formed 
by a splitting of the fascia coracoclavicularis and that the fascia 
is continued from the lower margin of the muscle to become 
continuous with the fascia axillaris. 

Smaller Pectoral Muscle (M. pectoralis minor). 

Clean the external surface of the muscle by removing the an- 
terior layer of the investing fascia. Examine carefully its form, 
position, origin, insertion, action, and innervation, but do not 
reflect the muscle until later. 

Axillary Blood-vessels. 

Remove the so-called costocoracoid membrane, viz., that 
portion of the fascia coracoclavicularis which extends between 
the clavicle and the upper border of the M. pectoralis minor. 
The fossa axillaris may now be entered from above. Remove 
any visible areolar tissue and fat and study carefully in this 
situation the relations of the axillary artery and vein to one 
another and to the large bundle of nerves. Note that all are 

5 



66 



LABORATORY MANUAL OF HUMAN ANATOMY 



enclosed in a tough sheath (prolongation of fascia praeverte- 
bralis). 

Clean the axillary blood-vessels carefully and study them. 
Into what three parts is it customary arbitrarily to subdivide 




Cviii 



ci 



Plexus cervicobrachialis. (After P. Eisler, from Rauber's Text-Book.) Ventral view. 
h, N. hypoglossus; dh, ramus descendens N. hypoglossi, which, along with dc, the ramus de- 
scendens cervicalis, forms the ansa hypoglossi ; om, N. occipitalis minor ; au, N. auricularis magnus ; 
sec, N. cutaneus colli ; a, to N. accessorius ; spc, Nn. supraclaviculares ; p, N. phrenicus ; ds, N. dorsalis 
scapulae; sps, N. suprascapularis ; ss, Nn. subscapulares ; sc, N. subclavius; ax, N. axillaris; co, N. 
to M. coracobrachialis ; It, N. radialis; me, N. musculocutaneus ; M, N. medianus; ta, Nn. thoracales 
anteriores ; tt, N. thoracalis longus ; U, N. ulnaris ; cm, N. cutaneus antibrachii medialis ; ci, N. cutaneus 
brachii medialis ; ih, N. intercostobrachialis. (From Barker, The Nervous System, New York, 1899, p. 
324, Fig. 186.) 

the axillary artery? Study the relations of each of these three 
portions. What branches come from the first portion? What 
from the second! What from the third! Clean each of these 



DISSECTION OF THE UPPER EXTREMITY 67 

branches carefully and follow them to their terminations, com- 
paring their behavior with the text-book descriptions. Deal simi- 
larly with the axillary vein and its tributaries. 

Subclavius Muscle (M. subclavius). 

Clean it. Examine its form, position, origin, insertion, action, 
and innervation. 

With a small hand-saw excise the middle third of the clavicle. 
Eeflect the M. subclavius. 

Brachial Plexus (Plexus brachialis). (Fig. 17.) 

Divide the M. pectoralis minor four centimetres from the 
coracoid process and reflect the two portions lateralward and 
medialward respectively, avoiding injury to the medial anterior 
thoracic nerve. Examine the continuity of the axillary artery 
and vein with the subclavian artery and vein. Ligature the ar- 
tery in two places at level of clavicle and cut between. Cut vein 
similarly. Turn axillary vessels downward. Clean thoroughly 
the nerves making up the brachial plexus. Study carefully the 
formation of the plexus, using the cadaver before you, Tra- 
mond's models, and text-book descriptions. Does the plexus in 
your cadaver differ from the type ordinarily described? If so, 
how? Make a careful drawing of the plexus in your subject, 
with its various branches, labelling each neatly. Note that the 
plexus can be divided into a supraclavicular portion (pars 
supraclavicularis) and an infraclavicular portion (pars infra- 
clavicularis) . All the short branches are counted as belonging 
to the former, even though they do not actually come off until 
the trunks are below the clavicle. 

In conjunction with the dissector of the head and neck, study 
the 

Pars supraclavicularis. 

(a) Posterior thoracic nerves (Nn. thoracales posteriores). 

(aa) Dorsal nerve of scapula (N. dorsalis scapulae) (0. T. nerve 

to rhomboids). 

(ab) Long thoracic nerve (N. thoracalis longus) (0. T. external 

respiratory nerve of Bell). 

(b) Anterior thoracic nerves (Nn. thoracales anteriores). 

(ba) Lateral (0. T. external). 

(bb) Medial (0. T. internal). 

(c) Subclavian nerve (N. subclavius). 

(d) Suprascapular nerve (N. suprascapularis) . 

(e) Subscapular nerves (Nn. subscapulares) . 

(f) Thoracodorsal nerve (N. thoracodorsalis) (0. T. middle or long 

subscapular) . 

(g) Axillary nerve (N. axillaris) (0. T. circumflex). 



68 LABORATORY MANUAL OF HUMAN ANATOMY 

The dissector of the arm next studies the 

Pars infraclavicularis. 

(a) Lateral cord (fasciculus lateralis) (0. T. outer cord). 

(aa) Musculocutaneous nerve (N. musculocutaneus) . 

(ab) Lateral or upper head of median nerve (N. medianus). 

(b) Medial cord (fasciculus medialis) (0. T. inner cord). 

(ba) Medial or lower head of median nerve (N. medianus). 

(bb) Ulnar nerve (N. ulnaris). 

(be) Medial cutaneous nerve of forearm (N. cutaneus anti- 
brachii medialis) (0. T. internal cutaneous). 

(bd) Medial cutaneous nerve of upper arm (N. cutaneus brachii 
medialis) (0. T. lesser internal cutaneous, or nerve of 
Wrisberg) . 

(c) Posterior cord (fasciculus posterior). 

(ca) Axillary nerve (N. axillaris) (0. T. circumflex, really 

supraclavicular ) . 

(cb) Radial nerve (N. radialis) (0. T. musculospiral). 

In order to get a good view of the posterior cord and of the Nn. sub- 
scapulares, the lateral and medial cords should be divided and reflected 
downward. 

Anterior Serratus Muscle (M. serratus anterior) (O. T. Serratus 
Magnus). 

Divide the posterior cord of the brachial plexus. Drag the 
arm forcibly from the body so as to put the M. serratus anterior 
on the stretch. Clean this muscle thoroughly and study carefully 
the exact course and distribution of the N. thoracalis longus and 
the A. thoracalis lateralis. Study the exact form, position, 
origin, insertion, action, and innervation of the M. serratus 
anterior. (Spalteholz, Fig. 311.) 

[When the student has completed this dissection of the ante- 
rior thoracic region and axillary fossa and has dissected that 
part of the back to which he is entitled, he may remove the upper 
extremity from the body and continue the dissection at a side- 
table. Cut through the Mm. serratus anterior, omohyoideus, 
and latissimus dorsi, the transverse and dorsal arteries of the 
scapula, and the Nn. suprascapularis et dorsalis scapulae.] 

REGION OF THE SHOULDER. 

Skin and Superficial Fascia. 

Place a block in the axillary fossa, and, beginning in front, 
dissect the skin off the anterior and lateral aspects of the shoul- 
der as far down as the insertion of the M. deltoideus. Eemove 
no fat with the skin. In the superficial fascia find the following : 



DISSECTION OF THE UPPER EXTREMITY 



69 



FIG. 18. 

Nn. supraclaviculares. 



N. cutaneus brachii medialis 



N. cutaneus brachii posterior 
(from the N. radialis) 



N. cutaneus antibracb 

dorsalis (from the 

N. radialis) 




N. cutaneus brachii lateralis 
(from the N. axillaris) 



Ramus ulnaris of the N . 
cutaneus antibrachii 
medialis 



The cutaneous nerves of the posterior surface of the shoulder and of the arm. (After Toldt, Anat. 
Atlas, Wieu., 1903, 3 Aufl., p. 831, Fig. 1264.) 



70 LABORATORY MANUAL OF HUMAN ANATOMY 

Arteries. 

(a) Cutaneous rami of ramus acromialis and ramus deltoideus of A. 

thoraco-acromialis. 
Veins. 

(a) Tributaries of cephalic vein. 

Nerves. (Fig. 18.) 

(a) Posterior supraclavicular nerves (Nn. supraclaviculares poste- 

riores) (0. T. sup ra-acromial branches). 

(6) Lateral cutaneous nerve of the upper arm (N. cutaneus brachii 
lateralis) (0. T. cutaneous branch of circumflex). Look for the 
trunk of this hooking around the posterior margin of M. del- 
toideus five centimetres above its insertion; dissect it carefully 
throughout its course in the superficial fascia. 

Deep Fascia. 

Eemove the superficial fascia and study the appearance and 
attachments of 

(a) Deltoid fascia (fascia deltoidea). 

(b) Subscapular fascia (fascia subscapularis) . 

(c) Supraspinous fascia (fascia supraspinata) . 

(d) Infraspinous fascia (fascia infraspinata). 

Deltoid Muscle (M. deltoideus) and the So-called Quadrilateral and 
Triangular Spaces. 

Hold the scapula down with hooks to make the fibres of the 
deltoid muscle tense, and carefully remove the deep fascia from 
its surface. Study carefully the form, position, origin, insertion, 
action, and innervation of the muscle. Note especially the three 
parts of the muscle corresponding to the three distinct muscles 
in the cat, deltoclavicular, delto-acromial, and deltospinal of 
Strauss-Durckheim. How does the texture of the middle portion 
(delto-acromial) differ from that of the anterior and posterior 
portions? (Of. Poirier et Charpy, Fig. 83.) Look for a subcu- 
taneous acromial bursa (bursa subcutanea acromialis). (Of. 
Spalteholz, Fig. 349. ) Does one exist in your cadaver ? 

Place the posterior surface of the limb on the table, and 
examine the area through which the A. circumflexa humeri pos- 
terior and the N. axillaris pass to the back part of the shoulder. 
How is this area, "quadrilateral space," bounded above, 
below, lateralward, and medialward? Clean the surfaces and 
edges of the muscles of this region. What is the so-called "tri- 
angular space?" How is it bounded above, below, and lateral- 
ward? Follow the A. circumflexa scapulae (0. T. dorsalis 
scapulae) through this space. 

Place the anterior surface of the limb on the table, and ex- 
amine the boundaries of the quadrilateral and triangular 
spaces from behind. 



DISSECTION OF THE UPPER EXTREMITY 71 

Divide the M. deltoideus close to its origin and reflect it 
downward, avoiding injury to the ramus acromialis of the A. 
thoraco-acromialis. Examine carefully the subdeltoid bursa 
(bursa subdeltoidea) and the subacromial bursa (bursa sub- 
acromialis). 

Beneath the deltoid dissect out carefully 

(a) Posterior circumflex artery of humerus (A. circumftexa humeri pos- 

terior). 

(b) Anterior circumflex artery of humerus (A. circumftexa humeri an- 

terior). 

(c) Veins corresponding to these arteries. 

(d) Axillary nerve (N. axillaris) (0. T. circumflex). 

(da) Muscular rami (rami musculares). 

(daa) N. teres minor. 

(dab) Nn. deltoidei. 

(db) Lateral cutaneous nerve of the upper arm (N. cutaneus 

brachii lateralis). 



Teres Major Muscle (M. teres major) ("Larger Round Muscle"). 
Study carefully its form, position, origin, insertion, action, 
and innervation. Note especially the torsion the muscle un- 
dergoes. Review the relation of this muscle to the quadrilateral 
and triangular spaces. Between the tendon of insertion and 
the bone find the bursa of this muscle (bursa M. teretis ma- 
joris). Between the tendon of the M. teres major and that of 
the M. latissimus dorsi find the bursa of the latter muscle 
(bursa M. latissimi dorsi). Do you find any trace of a M. 
dorsi-epitrochlearis ? Examine carefully at this stage the 
exact mode of termination of the tendons of the Mm. pectoralis 
major and latissimus dorsi. 

Ligaments of Shoulder-blade and Acromioclavicular Articulation. 

Ligaments of the shoulder-blade. Study 

(a) Coraco-acromial ligament (ligamentum coraco-acromiale) . 

(b) Superior transverse ligament of scapula (Lig. transversum scapulae 

inferius). 

(The latter will be seen at a later stage of the dissection.) 
Acromioclavicular articulation (articulatio acromioclavicularis) . Study 

(a) Joint-capsule (capsula articulari$) . 

(b) Acromioclavicular ligament (ligamentum acromioclaviculare) . 

(c) Intercalated disk of fibrocartilage (discus articularis) . Is one 

present ? 

(d) Coracoclavicular ligament (ligamentum coracoclaviculare) . 

(da) Anterior, lateral, quadrangular part, or trapezoid ligament 
(Lig. trapezoideum) . 



72 LABORATORY MANUAL OF HUMAN ANATOMY 

(db) Posterior, medial, triangular part, or conoid ligament (Lig. 

conoideum). 

Between (da) and (db) look for the bursa of the coraco- 
clavicular ligament (bursa ligamenti coracoclavicularis) . 

Deep Muscles of the Shoulder. 

Saw through the acromion at its junction with the spina 
scapulae. Cut through the fascia covering the M. teres minor 
and reflect it medialward; the septum passing from the fascia 
infraspinata between the M. teres minor and the M. infraspi- 
natus will be easily found and is the guide in the separation of 



FIG. 19. 



Caps, 
acrom.-clav. 



Lig. Lig. 
trapezoid. conoid. 



Lig. 
trans, scap. sup. 



Clavicula 



Lig. coraco- 

acromiale 




Connection of the clavicle with the scapula ; anterior view. (From Poirier et Charpy, 
Traite" d'Anat. hum., Paris, 1899, 2 ed., t. i. p. 610, Fig. 627.) 

the two muscles. Avoid injury to the A. circumflexa scapulae 
between the M. teres minor and the scapula. Clean the following 
muscles : 

(a) Supraspinous muscle (M. supraspinatus) . 

(b) Smaller round muscle (M. teres minor). 

(c) Infraspinous muscle (M. infraspinatus). 

(d) Subscapular muscle (M. subscapularis) . 

Study the form, position, origin, insertion, action, and inner- 
vation of each. Find the bursa M. subscapularis and with a 
probe demonstrate its continuity with the synovial cavity of the 
shoulder- joint. In front of the upper part of the tendon of the 
M. subscapularis, look for the bursa M. coracobrachialis. 



DISSECTION OF THE UPPER EXTREMITY 73 

Vessels and Nerves behind the Scapula. 

Cut through the M. infraspinatus three centimetres from its 
insertion into the tuberculum majus humeri, avoiding injury to 
vessels beneath. Examine the bursa M. infraspinati between the 
tendon of insertion of the muscle and the articular capsule of 
the shoulder-joint. Reflect the main body of the muscle cau- 
tiously backward and medialward. Cut through the M. supra- 
spinatus in a similar way and reflect it medialward. Study 

(a) Transverse artery of scapula (A. transversa scapulae) (0. T. supra- 

scapular). 

Does it pass over or under the Lig. transversum scapulae supe- 
rius? How is the artery distributed? Find 
(aa) Acromial ramus (R. acromialis) going through M. trapezius 
to rete acromiale. 

(b) Transverse vein of scapula (V. transversa scapulae). 

Of what vein is it a tributary? 

(c) Suprascapular nerve (N. suprascapularis) . 

Does it pass over or under the Lig. transversum scapulae supe- 
rius? Review it to its origin from the supraclavicular portion of 
the brachial plexus. Note especially the branches 

(ca) N. supraspinatus. 

(cb) N. infraspinatus. 

(d) Circumflex artery of scapula (A. circumftexa scapulae) (0. T. dor- 

salis scapulae artery). Study its exact course from origin to ter- 
mination. Note the opportunities for anastomoses about the 
scapula among its three main arteries 

(1) A. transversa colli. 

(2) A. transversa scapulae. 

(3) A. subscapularis. 

Since (1) and (2) come from the A. subclavia (first portion) and 
(3) comes from the A. axillaris (third portion), the establishment 
of a collateral circulation after ligation of the subclavian or axil- 
lary between the origins of the arteries mentioned is seen to be 
easily possible. 

DISSECTION OF ARM AND FOEEAEM. 

Surface Anatomy. 

The principal features were studied at the beginning of the 
dissection. The student should now pay attention to certain 
special points, using his own arm or that of a companion as a 
control. 

(a) With the help of the photographs and accompanying key in Gerrish's 

Anatomy (2d edition, Figs. 971 to 979), identify the surface promi- 
nences due to the various muscles of the arm and forearm. 

( b ) Note that the vena cephalica runs in the sulcus bicipitalis lateralis and 

the vena basilica in the sulcus bicipitalis medialis. 



74 LABORATORY MANUAL OF HUMAN ANATOMY 

(c) Follow the medial margin (mar go medialis) downward to the medial 

epicondyle (epicondylus medialis), and the lateral margin (mar go 
later alis) downward to the lateral epicondyle (epicondylus later- 
alis). Note that, though the margo lateralis is more salient than 
the margo medialis, the epicondylus medialis is more prominent 
than 'the epicondylus lateralis. Feel through the skin behind the 
medial epicondyle for the groove for the ulnar nerve (sulcus N. 
ulnaris). Press upon the nerve in your own arm (" funny bone," 
or " crazy bone"). Whence does the sensation seem to come? 

(d) Observe the prominence due to the olecranon (1) when the forearm 

is extended, (2) when the forearm is flexed. Standing in front of 
a living body, take the two elbow-joints in the palms of the two 
hands, with the -forefinger resting on the tip of the olecranon, the 
thumb on the lateral epicondyle, and the middle finger on the 
medial epicondyle. Ask the person to flex and extend the fore- 
arms, and notice changes in relative position of bony points. Note 
the relative distance between the level of the olecranon and the 
epicondyles. The olecranon is a little nearer to the medial than 
to the lateral epicondyle, especially in children. Observe the free 
movement of the skin over the olecranon, due to a subcutaneous 
bursa. To what extent is the posterior surface of the ulna sub- 
cutaneous? Feel for the margins of the semilunar notch (incisura 
semilunaris) . 

(e) Extend the forearm. Place the thumb of the left hand on the lateral 

epicondyle of the humerus; seize the hand with your right hand 
and rotate gently. Feel the rounded head of the radius (capitulum 
radii) rotating immediately below the epicondyle. 
(/) In the forearm palpate 

(fa) Dorsal margin of ulna (margo dorsalis ulnae). 

(fb) Styloid process of ulna (processus styloideus ulnae). 

(fc) Rounded head of ulna (capitulum ulnae). 

(fd) Styloid process of radius (processus styloideus radii). 

(fe) Radial artery (A. radialis). 

(ff) The tendons about the wrist. 

Skin and Superficial Fascia. 

Cut through the skin in the middle line of the anterior sur- 
face of the upper arm and the volar surface of the forearm as 
far as the wrist. Make a circular incision around the forearm 
just proximal to the wrist- joint. Remove the skin, dissecting 
lateralward and medialward, but take none of the fat of the 
superficial fascia with it. Preserve the skin, as it makes the 
best primary wrapping for the extremity in the intervals between 
dissection-periods. In the superficial fascia dissect out carefully 
the following : 

Nerves. (Cf. Fig. 20, and Spalteholz, Figs. 792 and 793.) 

(a) Intercostobrachial nerves (Nn. intercostobrachiales) (0. T. inter- 
costohumeral). 



DISSECTION OF THE UPPER EXTREMITY 



75 



FIG. 20. 



Clavicula 



M. subdavius 
A. subdavia 



Plexus brachialis (pars infracla 
vicularis) fasciculi medialis 
and lateralis 

Proccssus coracoideus 



Kami musculares for the 
M. coracobrachialis 



N. musculocutaneus 
M. coracobrachialis - 

N. medianuB - 

N. radialis - 
A. brachialis 



N. cutaneus antibrachii 
medialis 



M. biceps bracMi 



V. cephalica 



N. cutaneus antibrachii 
lateralis 



V. mediana antibrachii . 



Cartilago costalis 1. 
V. subdavia 




N. intercostobrachialis 

Ramus anastomoticus from the 

plexus brachialis to the N. 
/ intercostobrachialis 

^ Xn. subscapulares 

N. thoracodorsalis 
^M- subscapularis 

M. teres major 



_. M. latissimus dorsi 



-Kami cutanei for the skin of 
the axillary fossa 



N. cutaneus brachii medialis 



Kami musculares of the N. radialis to the 
~~Caput longnm ) of the M. caput mediale of 

> triceps the M. triceps 
-Oaput mediale ) brachii brachii 




_ .N. ulnaris 
-Ramus volaris 
-Ramus ulnaris 
M. brachialis 
V. basilica 
Septum intermusculare mediale 



V. mediana cubiti 



Lacertus fibrosus 



of the N. cutaneus anti- 
brachii medialis 



The deep nerves of the shoulder and arm seen from the anterior and medial side. (From Toldt, 
Anat. Atlas, Wieii, TJU3, 3 Ann., p. 822, Fig. 1254.) 



7G 



LABORATORY MANUAL OF HUMAN ANATOMY 



(b) Medial nerve of forearm (N. cutaneus antibrachii medialis) (0. T. 

internal cutaneous). (See Fig. 24, p. 81.) 

(ba) Anterior cutaneous rami to upper arm (rami cutanei 

brachii anterior es). 

(bb) Ulnar ramus (ramus ulnaris) (0. T. posterior branch). 
(be) Volar ramus (ramus volaris) (0. T. anterior branch). 

(c) Medial nerve of upper arm (N. cutaneus brachii medialis) (0. T. 

lesser internal cutaneous, or nerve of Wrisberg). 

FIG. 21. 



Integumentum commune 



Fascia superficialis 



Fascia brachii 
(lamina superficialis) r 



Point where the N. cutaneus 
antibrachii medialis comes 
through the fascia brachii 
Perimysium externum 
of the M. biceps brachii 



Fascia brachii 
(lamina profunda) 

N. cutaneus 
antibrachii later 

Bundle of vessels and nerv 
Vena 

Septum 
intermusculare mediate 

N. utnarii 
Fascia, brachii 
(lamina superficialis) 




Vena cutanea 
( V. cephalica) 



._ M. biceps brachii 

Line of uni9n of the 

lamina superficialis with the 

lamina profunda fasciae 
brachii 

M. brachialis 
N. radialis 
M. brachioradialis 
. Humerus 

Septum intermusculare 
laterale 

M. triceps brachii 
Fascia superficialis 

Integumentum commune 



The structures in the lower third of the arm cut across like stairs. 
(After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 264, Fig. 502.) 



(d) Radial nerve (N. radialis) (0. T. musculospiral). Only super- 

ficial branches of this nerve are seen as yet. 

(da) Posterior cutaneous nerve of upper arm (N. cutaneus 

brachii posterior) (0. T. upper external cutaneous 
branch of musculospiral). 

(db) Posterior cutaneous nerve of forearm (N. cutaneus anti- 

brachii dorsalis) (0. T. lower external cutaneous branch 
of musculospiral). 

(e) Musculocutaneous nerve (N. musculocutaneus) . 

(ea) Lateral cutaneous nerve of forearm (N. cutaneus anti- 
brachii lateralis) (0. T. terminal cutaneous branch). 
(See Fig. 24.) 



DISSECTION OF THE UPPER EXTREMITY 77 

Veins. (See also Fig. 24.) 

(a) Basilic vein (V. basilica}. At what point does it pierce the fascia 

brachii ? 

(b} Cephalic vein (V. cephalica}. 
(c} Median vein of elbow (V. mediana cubiti}, from V. cephalica 

obliquely upward to V. basilica. 
Instead of (c) there may be a 
(d) Median vein of forearm (V. mediana antibrachii}, bifurcating at 

head of elbow into 

(da} Basilic median vein (V. mediana basilica}, 
(db) Cephalic median vein (V. mediana cephalica}. 
In phlebotomy either the V. mediana cubiti or the V. mediana basilica 
is selected. Note the relations, to these veins, of the lacertus fibrosus, 
the arteria brachialis, and the ramus volaris of the N. cutaneus anti- 
brachii median's. 

FIG. 22. 

Integumentum commune* 

Bundle of vessels and nerves _^^__ ,^ 

\'< IHL rcpfKitii'd 
Vena basilica -^M /^3^^E^#m\l 

Fascia brachii (lamina 

N.umans^MOBaaKS^Bm """""" ; 

-M. brachialis 




_ -M. brachiodorsalis 

Humerus ' 

M. triceps brachii -^HH^^M^H^Septum intermusculare 

laterale 



Cross-section of the right arm near its lower end, to show the grouping of the muscles and their 
relation to muscle-sheaths or fasciae. Half schematic. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., 
p. 264, Fig. 503.) 

Lymphatics. 

(a) Superficial lymph-glands of elbow (lymphoglandulae cubitales 
superficiales ) . 

They may be enlarged in infection of the hand or fingers. 

Deep Fascia of Arm (Fascia brachii) (O. T. Brachial Aponeurosis). 
(Figs. 21 and 22.) 

Having isolated the vessels and nerves of the superficial 
fascia, remove all the fat so as to clean the surface of the deep 
fascia. Note 

(a) Its continuity with the deltoid and axillary fascia above and with the 

deep fascia of the forearm below. 

(b) That it is multiply perforated for the passage of vessels and nerves, 

and 

(c) The lacertus fibrosus. 



78 LABORATORY MANUAL OF HUMAN ANATOMY 

Make an incision through the fascia brachii along the middle 
line of the front of the upper arm and a circular incision proxi- 
mal to the lacertus fibrosus. Reflect the fascia brachii from the 
front of the arm in two flaps, medial and lateral, until the strong 
lateral and medial intermuscular septa are reached, 

(a) Medial intermuscular septum (septum intermusculare [humeri] 

mediate) (0. T. internal intermuscular septum). 

(b) Lateral intermuscular septum (septum intermusculare [humeri] lat- 

erale) (0. T. external intermuscular septum). 

Structures in Front of the Intermuscular Septa (Anterior Compart- 
ment of Arm). (See also Fig. 20.) 

Arteries. 

Arrange the axillary artery and vein and the divided nerves of the 

brachial plexus in their proper order and tie them to a small stick, 

four centimetres long, placed transversely. Fasten this with a loop of 

cord to the processus coracoideus. Clean the brachial artery carefully 

throughout its whole extent and study its relations. 

(a) Brachial artery (A. brachialis). At what point does it begin? 

Where and how does it end? With what veins, nerves, 

and muscles does it enter into relation in the various 

parts of its course? Study the mode of origin, course, 

and distribution of the following branches : 

(aa) Deep artery of upper arm (A. prof undo, brachii) (0. T. 

superior profunda). Note its relation to the radial 
nerve. Its branches and general distribution will be 
studied later. 

(ab) Superior ulnar collateral artery (A. collateralis ulnaris 

superior) (0. T. inferior profunda). Note its relation 
to the ulnar nerve. How does it arise? 

(ac) Inferior ulnar collateral artery (A. collateralis ulnaris in- 

ferior) (0. T. anastomotica magna). Note its anterior 
and posterior divisions. 
Veins. 

(a) Brachial veins (Vv. brachiales). 

(aa) Radial veins (Vv. radiales). 

(ab) Ulnar veins (Vv. ulnar es}. 

(ac) Basilic veins (Vv. basilicae), portions beneath fascia 

brachii. 

(b) Cephalic vein (V. cephalica), portion in a duplicature of the fascia 

brachii. 

Nerves. 

(a) Medial cutaneous nerve of upper arm (N. cutaneus brachii me- 

dialis) (0. T. lesser internal cutaneous, or nerve of Wrisberg). 

(b) Medial cutaneous nerve of forearm (N. cutaneus antibrachii me- 

dialis) (0. T. internal cutaneous). 

These nerves (a) and (b) have been studied before, with the exception 
of their parts subjacent to the fascia brachii. 



DISSECTION OF THE UPPER EXTREMITY 



79 



(c) Median nerve (N. medianus). How does it arise? Note its 

changing relations as regards the A. brachialis. Does it give off 
any branches above the elbow? 

(d) Ulnar nerve (N. ulnaris). Study its course in the upper part of 

the arm. Where and how does it leave the anterior compartment 
of the upper arm? 

FIG. 23. 



Ram. acrom. 



Aa. circ. hum. 



A. prof, hum 




A. thor. sup. 
....Ram. pect. 



...A. thor. lat. 



...A. circ. scap. 



A. coll. uln. inf. 



A. rad. recur 



A. recur, uln. ant. 

A. rec. uln. post. 

A. ulnaris 



A. mediana 



Scheme of the branches of the brachial artery. (From Poirier et Charpy, Trait6 d'Anat. hum., Paris, 

1901, t. ii. p. 732, Fig. 416.) 



(e) Musculocutaneous nerve (N. musculocutaneus) . Carefully dissect 
out this nerve and its branches. How does it arise from 
the plexus brachialis ? Study its exact course throughout 
the upper arm. 
(ea) Muscular rami (rami musculares}. 

(eaa) Nerve to M. coracobrachialis. 



80 LABORATORY MANUAL OF HUMAN ANATOMY 

(eab) Nerve to M. biceps brachii. 

(eac) Nerve to M. brachialis. 

(eb) Lateral cutaneous nerve of forearm (N. cutaneus anti- 
brachii lateralis), already studied. (See Fig. 24.) Note 
the cutaneous ramus given off above the elbow to supply 
the skin over the lateral region of the elbow. 
Muscles. 

The muscles of the anterior compartment should now be thoroughly 
cleaned. Study the form, position, origin, insertion, action, and inner- 
vation of each. 

(a) Biceps muscle of upper arm (M. biceps brachii). 

(aa) Long head (caput longum}. The exact origin will be 

examined later. Observe the prolongation of the syno- 
vial membrane of the shoulder- joint in the sulcus inter- 
tubercularis. It is called the intertubercular mucous 
sheath (vagina mucosa intertubercularis). 

(ab) Short head (caput breve). The insertion, the lacertus 

fibrosus, and the bursae related to the tendon of insertion 
will be examined a little further on. 

Comparative anatomy indicates that the M. biceps 
brachii is really a quadrigeminal muscle, coracoradial, 
coracocubital, glenoradial, and glenocubital (Krause). 

(b) Coracobrachial muscle (M. coracobrachialis) . 

Find the bursa M. coracobrachialis. Note that the M. coraco- 
brachialis really consists of two distinct bundles; these fuse at 
their two extremities, but not in the middle, thus forming a 
tunnel three centimetres long for the N. musculocutaneus. Note 
that the M. coracobrachialis in the arm corresponds to the ad- 
ductor system of muscles in the thigh. 

Find the fibrous arch extending from the insertion of the 
tendon of the muscle to the inferior border of the tuberculum 
minus (arch of Struthers). 

(c) Brachial muscle (M. brachialis) (0. T. brachialis anticus). 

How is it related to the medial and lateral bicipital sulci? 

Bend of the Elbow (Cubital Fossa). (Fig. 24.) 

Dissect in the depth between the M. brachialis and the M. 
brachioradialis for the radial nerve and the radial recurrent 
artery. Find the branch of the latter which perforates the sep- 
tum intermusculare laterale to join the rete articulare cubiti, 
thus establishing an anastomosis with the A. profunda brachii. 
Seek the branches from the radial nerve to the M. brachioradialis 
and the M. extensor carpi radial is longus. 

Compare the bend of the elbow with the popliteal space. 
Study the lacertus fibrosus (0. T. semilunar fascia) carefully 
and examine its relations. Why are these of surgical impor- 
tance? What is the shape of the space in front of the elbow? 
How is it bounded ? In this space examine the following : 



DISSECTION OF THE UPPER EXTREMITY 



81 



FIG. 24. 



N. cutaneus f Ramus ulnaris 
antibrachii medialis { R amus volaris ji 



N. cutaneus antibrachii lateralis 



Ramus superflcialis of the N. radialis - 



Ramus palmaris N. mediani _- 




- Ramus cutaneus palmaris 
of the N. ulnaris 



The cutaneous nerves of the volar surface of the forearm. (After Toldt, Anat. Atlas, Wien, 
1903, 3 Aufl., p. 830, Fig. 1263.) 



82 LABORATORY MANUAL OF HUMAN ANATOMY 

(a) Brachial artery (A. brachialis). 

(aa) Radial artery (A. radialis). 

(ab) Ulnar artery (A. ulnaris}. 

(b) Tendon of M. biceps brachii. Find 

(ba) Bursa bicipitoradialis. 

(bb) Bursa cubitalis interossea. 

(c) Median nerve (N. medianus). 

Remove the fat and clean the structures so as to examine in 
the floor of the space 

(a) Brachial muscle (M. brachialis). 

(b) Supinator muscle (M. supinator) (0. T. supinator brevis). 

Divide the lacertus fibrosus (0. T. semilunar fascia or bicipi- 
tal fascia), pull the M. brachioradialis far later alward and the 
M. pronator teres far medialward. Examine carefully 

(a) Radial nerve (N. radialis). 

(aa) Deep ramus (ramus profundus). 

(ab) Superficial ramus (ramus superficialis) . 

(b) Radial recurrent artery (A. radialis recurrens). 

(c) Inferior ulnar collateral artery (A. collateralis ulnaris inferior) (0. 

T. anastomotica magna). 

(d) Anterior ulnar recurrent artery (A. recurrens ulnaris anterior). 

(e) Epitrochlear lymph-gland. 

Structures behind the Intermuscular Septa (Posterior Compartment 

of Arm). 

Dissect the fascia brachii off the M. triceps, cleaning its three 
heads thoroughly. This will be facilitated by putting the muscle 
on the stretch (flex the forearm and raise the inferior angle of 
the scapula as far as possible). Dissect out the A. profunda 
brachii and the N. radialis and their branches. Study 

(a) Triceps muscle (M. triceps brachii}. 

Study its form, position, origin, insertion, action, and 
innervation. 

(aa) Long head (caput longum). 

(ab) Lateral head (caput laterals} (0. T. outer head). 

(ac) Medial head (caput mediale) (0. T. inner head). 
Compare the M. triceps with the M. quadriceps femoris. Is a 

M. subanconaeus present? 

(b) Radial nerve (N. radialis) (0. T. musculospiral nerve). 

Insert a grooved director or the handle of a scalpel 
beneath the lateral head of the triceps muscle along the 
sulcus N. radialis (0. T. musculospiral groove). With 
this as a guide, cut through the lateral head of the triceps 
and reflect it medialward and downward. Study the rela- 



DISSECTION OF THE UPPER EXTREMITY 



83 



M. trapezius 



FIG. 25. 

^Rami cutanei dorsalcs Nn. thoracalium 

'V . t Mm. rhomboidei, minor and major 

M. Icrator scapulae 
N. dorsalis scapulae 

Mfprcwpfoafttt 



M. infraspinatus 

f . s^prascapularis 

iiy. transversum scapulae superius 



Lig. transversum, 
'scapulae inferius 






Medial axillary space' " 

(triangular) 
N. cutaneus brachii lateralis 



M. triceps brachii 

Caput medial 

Twig for the M. anconaeus and for the elbow-joint 

N. cutaneus brachii posterior < 



M. deltoideus 



\Lateral axillary 
space (quadri- 
lateral) 
radialis 



^Rami muscu- 
lares of the 
N. radialis 
Caput laterale of the 
M. triceps brachii 

Ramus muscularis 
for the M. brachialis 



If. brachialis 



M. brachioradialis 



N. cutaneus anti- 
brachii dorsalis 



The nerves of the muscles about the shoulder-joint and of the M. triceps, together with the cutane- 
ous branches of the Nn. axillaris and radialis, and the distribution of the N. dorsalis scapulae. The 
acromion has been sawed off and drawn lateralward and the Mm. supraspinatus and infraspinatus cut 
through. The lateral head of the M. triceps brachii has been cut through obliquely and its two parts 
turned back. (After Toldt, Anat. Atlas, Wien, 1903, 3 Aufl., p. 824, Fig. 1256.) 






84 LABORATORY MANUAL OF HUMAN ANATOMY 

tions of the nerve closely in the different parts of the upper 
arm. Branches in upper arm : 

(ba) Posterior cutaneous nerve of upper arm (N. cutaneus brachii 

posterior) (0. T. upper external cutaneous branch of mus- 
culospiral). (Already studied; vide supra.) 

(bb) Muscular rami (rami musculares). 

(bba) To three heads of M. triceps brachii. 

(bbb) To M. anconaeus. 

(bbc) To M. brachioradialis (already studied). 

(bbd) To M. extensor carpi radialis longus (already 

studied). 

(bbe) To M. brachialis. 

(be) Posterior cutaneous nerve of forearm (N. cutaneus anti- 
brachii dorsalis) (0. T. lower external cutaneous branch 
of musculospiral. (See Fig 1 . 28.) 

(c) Deep artery of upper arm (A. prof undo, brachii) (0. T. superior 

profunda artery). 

Study its relations in all parts of its course. 
Branches : 

(ca) Deltoid ramus (ramus deltoideus). 

(cb) Middle collateral artery (A. collateralis media). Note its 

contribution to the rete articulare cubiti. 

(cc) Radial collateral artery (A. collateralis radialis) (0. T. artic- 

ular branch of superior profunda). 

(cd) Nutrient arteries of the humerus (Aa. nutriciae humeri). 

These sometimes come from the brachial artery proper. 

(d) Other structures in back of arm. 

Dissect carefully above the back of the elbow 

(da) Ulnar nerve (N. ulnaris), through the sulcus N. ulnaris. 

(db) Superior ulnar collateral artery (A. ulnaris collateralis supe- 

rior) (0. T. inferior profunda). Note relation to rete 
articulare cubiti. 

(dc) Ramus muscularis to medial head of M. triceps. This is 

sometimes called the " ulnar collateral nerve." 

(dd) Inferior ulnar collateral artery (A. collateralis ulnaris infe- 

rior) (0. T. anastomotica magna). Look for it beneath the 
tendon of the M. triceps, a little above the olecranon. 

(de) Bursa subtendinea olecrani. 

Look for a bursa subcutanea olecrani also and a bursa 
intratendinea olecrani. 



SHOULDER-JOINT (ARTICULATIO HUMERI, OR AR- 
TICULATIO SCAPULOHUMERALIS). 

This joint is an enarthrosis. (What is meant by this state- 
ment!) Review the muscles related to the joint and then remove 
them as follows : 

Cut through the origins of the M. coracobrachialis and the 
caput breve of the M. biceps brachii; divide the M. teres major 



DISSECTION OF THE UPPER EXTREMITY 



85 



midway between its origin and its insertion and the caput longum 
of the M. biceps four centimetres below its origin. Reflect these 
muscles. Carefully dissect from the capsule of the joint the Mm. 
supraspinatus, infraspinatus, teres minor, and subscapularis. 

FIG. 26. 

Cavity of the articulatio 
acromioclavicularis 



Clavicula --' 



M. supraspinatus 



Labrum glenoidale 



Bursa subdel- 
toidea 



M. deltoideus 







M. triceps 

Synovia! membrane and 
joint-capsule 



M. teres major 



Articulatio humeri, frontal section passing through the tuberositas minor, the arm adducted. 
Poirier et Charpy, Traite d'Anat. hum., Paris, 1899, 2 ed., t. i. p. 624, Fig. 636.) 



(From 



Clean the surfaces of the ligaments carefully, 
lowing : 



Study the fol- 



(a) Articular capsule (capsula articularis) . 

Note its cone shape, the summit attached to the labrum glenoi- 
dale, its base to the anatomical neck of the humerus. The attach- 
ment goes beyond the anatomical neck behind and below. Observe 
the variations in the thickness of the capsule in different parts. 

(b) Coracohumeral ligament (ligamentum coracohumerale) (0. T. acces- 

sory ligament). 

How is it attached medialward and lateralward ? Note that it 
corresponds to the interval between the tendons of the M. supra- 
spinatus and M. subscapularis, and so strengthens the capsule in a 
region otherwise feebly protected. 

(c) Glenohumeral ligaments. (Cf. Fig. 27.) 

Dissect off the posterior part of the capsula articularis, 
pull the bones well apart, look into the joint from behind, 






86 



LABORATORY MANUAL OF HUMAN ANATOMY 



and observe the following ligaments ; they are very variable 
in their development. 

(ca) Superior glenohumeral ligament (ligamentum glenohumerale 
superius) (0. T. coracobrachial ligament of Schlemm, 
supraglenosuprahumeral ligament of Faraboeuf). Note 
that it with the coracohumeral ligament forms a gutter in 
which the long head of the M. biceps runs. 

FIG. 27. 

Coracoglenoid ligament Lig. coracohumerale 

M. bizeps Superior glenohumeral ligament 
J M. subscapularis 

I y M. infraspinatus 



Inferior Middle 
gleno- gleno- 
humeral humeral 
ligament ligament 




M. teres minor 



Articulatio humeri, posterior view (the posterior part of the capsule and the head of the humerus 
have been cut away to show the articular surface of the anterior part of the capsule) . (From Poirier 
et Charpy, Traite" d'Anat. hum., Paris, 1899, 2 ed. ( t. i. p. 628, Fig. 639.) 



(cb) Middle glenohumeral ligament (ligamentum glenohumerale 

medium) (0. T. Lig. glenoideobrachiale internum of 
Schlemm or supraglenoprehumeral ligament of Faraboeuf). 
Between (ca) and (cb) is the interstice known as the "foramen 
ovale" of Weitbrecht. 

(cc) Inferior glenohumeral ligament (ligamentum glenohumerale 

inferius) (0. T. Lig. glenoideobrachiale inferius of 
Schlemm, pregleno-infrahumeral ligament of Faraboeuf). 
(d) Glenoid lip (labrum glenoidale) (0. T. glenoid ligament). 

Divide the capsula articularis and the glenohumeral ligaments 
in front and pull the head of the humerus away from the glenoid 
cavity. Examine the labrum glenoidale. Note the relation to it of 



DISSECTION OF THE UPPER EXTREMITY 87 

the long head of the M. biceps brachii above and of the long head 
of the M. triceps below. 
(e) Long head of biceps muscle (caput longum M. bicipitis brachii). 

Note its relations to the joint. Why is it of especial importance? 
Note its exact mode of origin. While in the joint, surrounded by 
the synovial membrane, it lies beneath a sort of inverted gutter 
formed by the superior glenohumeral ligament and by the posterior 
border of the coracohumeral ligament. 

[In the horse the tendon is inserted into the external surface of 
the capsula articularis; in sheep it becomes invaginated in the 
joint-capsule, is immediately related to the synovial membrane, 
being swung by a meso of the latter; in higher animals and man 
it is free in the joint. All these phylogenetic stages are repeated 
in the ontogeny of the human embryo. (Cf. Welcker, H., Die 
Einwanderung der Bicepssehne in das Schultergelenk, Arch. f. 
Anat. u. Physiol., Anat. Abth., Leipzig, 1871, p. 20.)] 
(/) Synovial membrane and its evaginations. 

Note exact extent of synovial membrane. Observe the 
following constant evaginations: 

(fa) Subscapular bursa, in the adult usually communicating with 

the M. subscapularis (already studied). 

(fb) Vagina mucosa intertubercularis (for tendon of long head of 

biceps muscle). 
(g) Movements of the joint. 

What muscles are concerned in the following movements? 

1. Flexion. 

2. Extension. 

3. Abduction. 

4. Adduction. 

5. Circumduction. 

6. Rotation. 

What structures check excessive movements in the directions 
mentioned ? 

What agencies contribute to keeping the joint surfaces in con- 
tact, i.e.) to maintaining the integrity of the joint? 

For the details of the anatomy of this and other joints, consult 
R. Fick, Handbuch der Anatomic und Mechanik der Gelenke (in 
Bardeleben's Handbuch), Jena, 1904. 

FOREARM AND HAND (ANTIBRACHIUM ET 

MANUS). 

Superficial Fascia of Dorsum of Hand. 

Make incisions through the skin along the margo ulnaris 
and the margo radialis of the hand. Dissect off the skin of the 
back of the hand (dorsum manus), detaching the flap at the roots 
of the fingers. Make an incision along the middle line of the 
dorsum of each digit and reflect the skin radialward and ulnar- 
ward in each instance. Take no fat with the skin. 



88 LABORATORY MANUAL OF HUMAN ANATOMY 



FIG. 28. 

N. cutaneus antibrachii dorsalis 



Ramus ulnaris of the N. cutaneus/' 
antibrachii medialis 



Ramus superficialis of the- 
N. radialis 



Ramus dorsalis manus 
of the N. ulnaris 




Ramus anastomoticus ulnaris 



Nn. digitales dorsales 



The cutaneous nerves of the dorsal surface of the forearm and hand. (After Toldt, Anat. Atlas, 
Wien, 1903, 3 Aufl., p. 831, Fig. 1265.) 



DISSECTION OF THE UPPER EXTREMITY 



89 



In the superficial fascia find the following : 

Nerves. (Fig. 28.) 

(a) Superficial ramus of radial nerve (ramus superficialis N. radialis) 

(0. T. radial branch of musculospiral). 

(aa) Ulnar anastomotic ramus (ramus anastomoticus ulnaris}. 

(ab) Dorsal digital nerves (Nn. digitales dorsales). 

(b) Dorsal ramus of hand from N. ulnaris (ramus dorsalis manus N. 

ulnaris) (0. T. dorsal branch of ulnar nerve). 
(ba) Dorsal digital nerves (Nn. digitales dorsales). 
Study exact distribution. 



FIG. 29. 

M. flex. poll. long. 
N. medianus 
M. palm, long j 
A. V. and N. inteross. volar. 
A. ulnaris v \ 
M. flex. dig. sub v \ 

N. ulnaris 



M. flex, carpi radialis 

/ M. pronator teres 
A. radialis 



M. flex. carpi N 
ulnaris 



Vv. ulnares^ 



M. flex, dig 
prof. 




M. brachioradialis 



Vv. radiales et 

" N. musculocut. 

,-N. radialis 



-M. ext. carpi 
rad. long. 



- -Radius 



/T " ^M. ext. carpi rad. 
- brevis 

v 
* M. supinator (superf. bundle) 

Ext. digitorum communis 
M. supinator (deep bundle) 

M. ext. digiti V. prop. 

Section passing below the upper third of the forearm. Frozen subject ; right forearm ; segment 
distal to the cut. (P. Fredet. ) (From Poirier et Charpy, Traite d' Anat. hum., Paris, 1901, 2 ed., t. n. p. 
166, Fig. 129.) 



Ulna 



M. anconaeus ""^W*": 



M. ext. carpi ulnaris 

A. interossea dors. 



Veins. 



(a) Venous network of back of hand (rete venosum dorsale manus). 
(aa) Dorsal metacarpal veins (Vv. metacarpeae dorsales). 

(aaa) Digital venous arches (arcus venosi digitales). 

(aaaa) Dorsal digital veins proper (Vv. digi- 
tales dorsales propriae). 
Note the relation of these veins to the V. basilica and V. cephal- 



90 LABORATORY MANUAL OF HUMAN ANATOMY 

ica. Observe the communication of the deep veins with these super- 
ficial veins. 

Arteries. 

(a) Dorsal metacarpal and cutaneous rami of dorsal digital arteries 
(Aa. digitales dorsales, Aa. metacarpeae dorsales). 

Deep Fascia. 

Remove all remaining fat of superficial fascia, so as to clean 
carefully the deep fascia of the forearm and back of the hand. 

(a) Deep fascia of forearm (fascia antibrachii) . 

How is it related to the fascia brachii? What becomes of it 
below? Note the relation of the lacertus fibrosus to this fascia. 
Look closely at the fibres composing the fascia and note their direc- 
tion. What nerves and blood-vessels perforate the fascia on the 
volar and dorsal surfaces of the forearm? Besides those already 
mentioned find (1) ramus cutaneus palmaris N. ulnaris, (2) ramus 
palmaris N. mediani, and (3) ramus superftcialis N. radialis. (See 
Fig. 24.) 

(b) Deep fascia of back of hand (fascia dor sails manus). 

Is it as thick as the fascia antibrachii? Note its attach- 
ment proximalward to the ligamentum carpi dorsale and 
distalward to the fibrous sheaths of the extensor tendons. 
The deeper connections of the fascia may be studied later. 
(ba) Dorsal ligament of the wrist (Lig. carpi dorsale) (0. T. 
posterior annular ligament). What are its relations proxi- 
malward and distalward? Ascertain exactly its attach- 
ments to the radius. What becomes of the ligament ulnar- 
ward ? 

Radial Artery and its Relations in the Forearm (A. radialis). 

Turn aside the ramus volaris of the N. cutaneus antibrachii 
medialis, the N. cutaneus antibrachii lateralis, and the super- 
ficial veins. Dissect off the fascia antibrachii, but take care not 
to disturb the nerves going to the palm. Where muscle-fibres 
arise from its deep surface, do not remove the fascia. Note care- 
fully the attachments of the fascia antibrachii in the depth. Dis- 
sect out the radial artery and its branches in the forearm, clean- 
ing the adjacent muscles, but disturbing the relations as little as 
possible. Where does the artery begin? Note exact relations 
to various muscles in different parts of its course. Between 
what tendons does that portion of the artery usually palpated 
in taking the pulse lief Note the relations of the radial artery 
to the radial veins (Vv. radiates) and to that part of the super- 
ficial ramus of the radial nerve beneath the fascia antibrachii. 
Study the origin and distribution of the following branches : 



DISSECTION OF THE UPPER EXTREMITY 



91 



FIG. 30. 



Fascia brachii -. 



V. cephalica^J 



^.Vasa lymphatica superficialia 



basilica 



^_ Lymphoglandulae cubitales superflciales 



A. brachialis and Vv. brachiales.^ 



Tendon oj the M. biceps brachii... \ 



, Lymphoglandulae cubitales 
profundae 



Vasa lymphatica profunda J 



Fascia antibrarhn 5 



L-_,Vasa lymphatica superficialia 



Arched lymphatic vessels passing on 
to the dorsum manus N 



Region of origin of the vasa lymphatica 
/ superficialia of the volar side of the 
forearm 

Arcus volaris superficialis 



Lymphatic vessels of the thumb. 



Lymphatic vessels of the finger passing 
on to the back of the hand 



Aponeurosis palmar is 

\ Lymphatic vascular network in the 
subcutaneous fatty tissue of the 
vola manus 

Subcutaneous adipose tissue o/ 
the finger 



Lymphatic vessels of the volar surface of the forearm and hand. In front of the elbow the fascia 
has been divided to expose the deep lymphatic vessels and glands. (After Toldt, Anat. Atlas, Wien, 
1900, 2 Aufl., p. 705, Fig. 1087.) 



92 



LABORATORY MANUAL OF HUMAN ANATOMY 



(a) Radial recurrent artery (A. recurrens radialis). 

(b) Superficial volar ramus (ramus volaris superficialis) . 

(c) Muscular rami (rami musculares). 

(d) Volar carpal ramus (ramus carpeus volaris) (0. T. anterior radial 

carpal). 
The other branches of the A. radialis are studied subsequently. 

Radial Nerve (N. radialis) (O. T. Musculospiral) in the Forearm. 

(a) Deep ramus (ramus profundus). 

(aa) Muscular rami (rami musculares). 

FIG. 31. 




FCR 



*** 

' A , 

j . iA ffl 



Ra CR 



at 



f/PC 




FCU 



Transverse section through the forearm of the opossum. 

ai, anterior interosseous nerve ; C, M. centralis; CR, M. condyloradialis ; CU, M. condylo-ulnaris; 
FCR, M. flexor carpi radialis ; FCU 1 , FCU, 2 lateral and medial portions of the M. flexor carpi ulnaris ; 
m, median nerve ; PL, M. palmaris longus ; R, radius ; Ra, M. radialis ; U, ulna ; u, ulnar nerve ; UL, 
M. ulnaris. The shaded areas represent the M. flexor sublimis digitorum. (After McMurrich, Amer. 
Jour, of Anat., Baltimore, 1903, vol. ii., No. 2, p. 196, Fig. 5.) 

(b) Superficial ramus (ramus superficialis) (0. T. radial branch of mus- 

culospiral ) . 
The branches of (a) and (b) are studied later. 

Superficial Muscles of Volar Surface and Ulnar Margin of Forearm. 

All the superficial muscles of the forearm should now be 
dissected out and cleaned. Avoid injury to the sheath of the 
flexor tendons in the lower part of the forearm (vagina tendinum 
Mm. flexorum communium). Note that the tendon of the M. 



DISSECTION OF THE UPPER EXTREMITY 



93 



palmaris longus runs in front of the ligamentum carpi trans- 
versum (0. T. anterior annular ligament). The ulnar artery 
and nerve also run superficial to the ligamentum carpi trans- 
versum, though under cover of the more superficial ligamentum 
carpi volare. (Cf. Spalteholz, Figs. 362 and 363.) Study care- 
fully the form, position, origin, and innervation of each of the 
following muscles : 

(a) Brachioradial muscle (M. brachioradialis) (0. T. supinator longus). 
This will be studied more particularly later, when the back and 
radial margin of the forearm are dissected. 

FIG. 32. 




Transverse section through the forearm of a human embryo of 4.5 cm. 

ai, anterior interosseous nerve ; C, M. centralis ; CR, M. condyloradialis ; CU, M. condylo-ulnaris ; 
FCR, M. flexor carpi radialis; FCU, M. flexor carpi ulnaris; m, median nerve; PL, M. palmaris longus; 
It, radius; Ra, M. radialis; U, ulna; u, ulnaf nerve; UL, M. ulnaris. The shaded areas represent the 
M. flexor sublimis digitorum. (After McMurrich, Amer. Jour, of Anat., Baltimore, 1903, vol. ii., No. 2, 
p. 200, Fig. 8.) 

(b) Long palmar muscle (M. palmaris longus). 

(c) Round pronator muscle (M. pronator teres) (0. T. pronator radii 

teres). 

(ca) Humeral head (caput humerale). 

(cb) Ulnar head (caput ulnare) (0. T. coronoid head). 

Note relation of ulnar head to median nerve and ulnar 
artery. 

(d) Radial flexor muscle of wrist (M. flexor carpi radialis). 



94 LABORATORY MANUAL OF HUMAN ANATOMY 

(e) Ulnar flexor muscle of wrist (M. flexor carpi ulnaris). 

(ea) Humeral head (caput humerale). 

(eb) Ulnar head (caput ulnare). 

What large nerve runs between these two heads'? 
(/) Superficial flexor muscle of the fingers (M. flexor digitorum sublimis). 

(fa) Humeral head (caput humerale). 

(fb) Radial head (caput radiale). 

Note space between these two heads for the passage of 
A. ulnaris and N. medianus. 

(See study of these flexor muscles by Professor McMurrich, of Ann 
Arbor, in the Amer. Jour, of Anat., Baltimore, vol. ii., No. 2.) 

Ulnar Blood-vessels and Ulnar and Median Nerves. 

These structures and their branches should next be carefully 
studied. Better to expose the ulnar artery, cut through the inter- 
muscular septum between the M. flexor digitorum sublimis and 
the M. carpi ulnaris. 

(a) Ulnar artery (A. ulnaris). 

Study its origin, course, relations, and the following branches : 

(aa) Recurrent ulnar arteries (Aa. recurrentes ulnares). 

(ab) Muscular rami (rami musculares). 

(ac) Volar carpal ramus (ramus carpeus volaris) (0. T. anterior 

ulnar carpal). 

(ad) Dorsal carpal ramus (ramus carpeus dorsalis) (0. T. poste- 

rior ulnar carpal). 

(ae) Common interosseous artery (A. interossea communis). 

(aea) Volar interosseous artery (A. interossea volaris) (0. 

T. anterior interosseous) (vide infra). 

(aeb) Dorsal interosseous (A. interossea dorsalis) (0. T. 

posterior interosseous), to be studied later. 

(b) Ulnar veins (Vv. ulnares). 

(c) Ulnar nerve (N. ulnaris). 

(ca) Palmar cutaneous ramus (ramus cutaneus palmaris). 

(cb) Dorsal ramus of hand (ramus dorsalis manus) (O. T. dorsal 

cutaneous). 

(cba) Dorsal digital nerves (Nn. digitales dor sales), 
already studied (vide supra}. 

(cc) Volar ramus of hand (ramus volaris manus) (branches in 

palm to be studied later). 

(cd) Rami musculares to M. flexor carpi ulnaris and part of M. 

flexor digitorum profundus. 

(d) Median nerve (N. medianus). 

Reflect the humeral head of the M. pronator teres and 
the radial head of the M. flexor digitorum sublimis, and 
study the median nerve throughout its whole course in the 
forearm. Note its relation to the A. mediana. Examine 
(da) Muscular rami (rami musculares) to Mm. pronator teres, 
flexor carpi radialis, palmaris longus, flexor sublimis digi- 
torum, i.e., to all muscles of superficial group except M. 
flexor carpi ulnaris. 



DISSECTION OF THE UPPER EXTREMITY 



95 



N. cutaneus antibrachii dorsalis^ 



\ I' 



N. 



FIG. 33. 



M. brachialis 
M. biceps brachtt 

.-Sulcus bicipitalis lateralis 



N. cutaneus antibrachii lateralis -^ 
Kami musculares - 



f Ramus superficialis 
N. radialis < 

' Ramus profundus _. 



r Sulcus bicipitalis medialis 

. A. brachialis 

..N. medianus 

I Ramus muscularis 
A. ulnaris 



Rami musculares-*^ 

M. brachioradialis- 

. (longus*- 

Mm. extensor es carpi] 
radiales } , 

\. brems._ 

V. cephalica -\ 

Branches of the N. cutaneus 
antibrachii lateralis 



'M. pronator teres 
-M. supinator 

M. flexor carpi radialis 

M. palmaris longus 

L flexor carpi ulnaris 
F A. radialis 



Ramus cutaneus - 



__Caput radiale of the M. flexor 
digitorum sublimis 



Ramus superficialis of the_. 
N. radialis 



.. Fascia antibrachii 



Ramus cutaneus palmaris of 
the N. ulnaris 



Small branches from the N. 
cutaneus antibrachii 
lateralis to the wrist 



Terminal branches of the N. cuta- 
neus antibrachii lateralis 






t !Ag. carpi volare 

.-Ramus profundus of the N. ulnaris 
N. ulnaris (ramus superficialis ) 



Ramus palmaris N. mediani, 



^M. palmaris brevis 



A. ulnaris/] 

The deep nerves of the volar side of the forearm. (After Toldt, Anat. Atlas, Wien, 1903, 3 Aufl., 

p. 826, Fig. 1258.) 



96 LABORATORY MANUAL OF HUMAN ANATOMY 

(db) Volar interosseous nerve of forearm (A r . interosseus anti- 

brachii volaris) (0. T. anterior interosseous). 
(dba) Rami musculares, to be studied a little further on. 

(dc) Palmar ramus (ramus palmaris N. mediani) (0. T. median 

palmar cutaneous), already examined (vide supra). 

Deep Structures on Volar Surface of Forearm. 

The remaining structures on the volar surface are now to be 
dissected out and carefully cleaned. 

Muscles. 

(a) Deep flexor muscle of fingers (M. flexor digitorum profundus). 

(b) Long flexor muscle of thumb (M. flexor pollicis longus). 

(c) Quadrate (or square) pronator muscle (M. pronator quadratus). 

Blood-vessels. 

(a) Volar interosseous artery (A. interossea volaris) (0. T. anterior 

interosseous). 

(aa) Median artery (A. mediana). 

(ab) Muscular rami (rami musculares). 

(b) Volar interosseous veins (Vv. interosseae volares). (Cf. Toldt, 

Fig. 1063.) 

Volar interosseous nerve (N. interosseus [antibrachii] volaris) (0. T. 

anterior interosseous). 

(a) Muscular rami (rami musculares) to the M. flexor digitorum pro- 
fundus (lateral or radial part) and M. pronator quadratus. 



WRIST AND PALM (CARPUS ET VOL A MANUS 

[PALM A]). 

Study the surface anatomy first, noting the thenar and hy- 
pothenar eminences. Palpate the bony prominences in the front 
of the wrist. To what is each due ? Observe the three prominent 
furrows in the thick skin of the palm. Note also the transverse 
sulci on the palmar surfaces of the digits. In what relation do 
these stand to the metacarpophalangeal articulations and the 
finger- joints? 

To reflect the skin make (1) a vertical incision along the 
middle line of the vola manus and (2) a transverse incision near 
the metacarpophalangeal junction from the margo radialis to 
the margo ulnaris of the hand. Reflect the flaps of skin ulnar- 
ward and radialward respectively, proceeding with caution. Do 
not reflect the ulnar flap quite to the ulnar margin of the hand 
until the insertion of the M. palmaris brevis into it has been 
made out. 



DISSECTION OF THE UPPER EXTREMITY 97 

Superficial Fascia of Palm. 

Note the subdivision of the fat into lobules. Study 

(a) The short palmar muscle (M. palmaris brevis). After examination 

cut through its origin and reflect it ulnarward, avoiding injury to 
ulnar artery and nerve. 

(b) Cutaneous nerves of palm. 

(ba) Eamus palmaris N. mediani. 

(bb) Eamus cutaneus palmaris N. ulnaris. 
(be) Eamus superficialis N. radialis. 

FIG. 34. 




Surface markings of the palm of the hand. The thick black lines represent the chief creases in the 
skin. (After Treves, Surg. Ap. Anat., London, 1889, 4th ed., p. 260, Fig. 26. ) 

Deep Fascia of Palm (Aponeurosis palmaris). 

Clean the surface of this and note its three parts. 

(a) Radial or thenar aponeurosis. 

(b) Middle or principal palmar aponeurosis. 

(c) Ulnar or hypothenar aponeurosis. 

(a) and (c) are relatively thin; (b) is very thick. What is 
the shape of (b)? To what does the base of the triangle corre- 
7 



98 LABORATORY MANUAL OF HUMAN ANATOMY 

spond? Note the distribution of the longitudinal and transverse 
fibres which constitute it. Examine carefully 
(d) Fasciculi transversi (0. T. transverse superficial ligament). 

Between each two digital slips of the aponeurosis palmaris, 
note the vessels and nerves. Cut through the fasciculi transversi 
in order to expose them better. Observe the septa passing into 
the depth from the margins of (b}. What three compartments 
are thus formed and what do they contain ? 

Superficial Volar Arch (Arcus volaris superficialis) (O. T. Superficial 
Palmar Arch) and Ulnar Artery. 

Cut through the narrow proximal part of the aponeurosis 
palmaris, reflect it distalward, and then remove it entirely. Be- 
move the ligamentum carpi volare and dissect out the ulnar 
vessels and ramus volaris manus N. ulnaris in the palm. Dissect 
out also the N. medianus and its branches; avoid injury to the 
muscular rami near the distal margin of the ligamentum carpi 
transversum. To follow out the digital vessels and nerves, make 
an incision along the middle line of the volar surface of each 
digit and reflect the skin ulnarward and radialward. 

How is the superficial volar arch formed! Study the ulnar 
artery and the superficial volar ramus of the radial artery. 
Where does the ulnar artery give off its deep volar ramus ! On 
the skin of your own palm draw a line with a colored pencil cor- 
responding to the position of the arcus volaris superficialis. 

Branches : 

(a) Common volar digital arteries (Aa. digitales volares communes) 

(0. T. palmar digital arteries). 

(aa) Volar digital arteries proper (Aa. digitales volares pro- 
priae) (0. T. collateral digital arteries). 

Note the point where the Aa. digitales volares communes 
receive the Aa. metacarpeae volares II.-IV. from the deep volar 
arch. Observe the relations of the digital arteries to the accom- 
panying nerves ; the relations of the proper digital differ from 
those of the common digital arteries. 

Median Nerve in Palm (N. medianus). (Fig. 35.) 

How does this nerve enter the palm? Note its relations to the 
ligamentum carpi transversum and to the mucous sheath of the 
flexor tendons. Study the following branches : 

(a) Muscular rami (rami musculares) to M. abductor pollicis brevis, M. 
flexor pollicis brevis (caput superficialis), and M. opponens pollicis. 



DISSECTION OF THE UPPER EXTREMITY 



99 



(b) Common volar digital nerves (Nn. digitales volares communes). 
Three from N. medianus. 
The second supplies M. lumbricalis II. 
The third gives off the ramus anastomoticus cum N. ulnari. 
(ba) Proper volar digital nerves (Nn. digitales volares propriae) 
(0. T. collateral digital nerves). Seven from N. me- 
dianus, 



FIG. 35. 



A. radial 



M. abductor poll, longus- 

N. medianus l^^^H 

M. flexor carpi rad. '-^^ 



M. adductor pollicis brevis 



M. flexor brevis pollic 



M. adductor pollicis 




N. ulnaris 

R. profundus 
R. superficialis 

M. abductor digit! V. 



M. flexor brevis digiti V. 



I Anastomosis 



M. interossea dorsalis I. 



N. digiti volaris { 



Nerves of the volar surface of the hand. (After Gegenbaur, Lehrb. der Anat. des Mensch., Leipzig, 
1899, 7 Aufl., Bd. ii. S. 499, Fig. 660.) 



I. and II. to skin of thumb; 

III. to skin of radial side of index and to M. lum- 
bricalis I.; 

IV. to skin of ulnar side of index; 

V. to skin of radial side of digitus medius; 

VI. to skin of ulnar side of digitus medius ; 

VII. to skin of radial side of digitus annularis. 
Work one of these out to its two terminals, (1) volar, 



V i ^ '' 

100 LABORATORY MANUAL OF HUMAN ANATOMY 

to the pulp, (2) dorsal, to the bed of the nail. On the 
terminals find the form of terminal corpuscle known as the 
Pacinian corpuscle (corpuscula lamellosa [Vateri, Pacini]). 

Volar Ramus of Ulnar Nerve in Hand (Ramus volaris manus N. 

ulnaris). (Fig. 35.) 

Note position of volar ramus of ulnar nerve in wrist (between 
ligamentum carpi volar e and ligamentum carpi transversum). 
Observe branching as follows : 

(a) Deep ramus (ramus profundus). 

Note its disappearance between M. abductor digiti quinti and M. 
flexor digiti quinti brevis. It will be studied later. 

(b) Superficial ramus (ramus super ficialis) . 

(ba) Ramus muscularis to M. palmaris brevis. 

(bb) Common volar digital nerve (N. digitalis volaris communis). 

FIG. 36. 

Aa. metacarpeae volares Aa. metacarpeae dorsales, II. and III. 

Tendons of the M. flexor digitorum 
profundus and Mm. lumbricales 

M. adductor pollicis^ .^^^^^S^^^^^^f' su P er -P cial \ Fascia of the back 
Deep fascia of the palm ^ ^^jJisM l*\ lUfi -.RffiwW dee P of the hand 

^^S^^^^^m^^i^mma^imm^'i^^' 




Thenar 

Arcus volaris superficialis Aponeurosis palmaris 

Cross-section of the palm of the hand through the bases of the metacarpal bones. Frozen 
section. Hand pronated. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 621, Fig. 1000.) 

1. Ramus anastomoticus cum N. mediani. 

2. Rami cutanei to skin of palm. 

3. Proper volar digital nerves (Nn. digit ales volares 

proprii) 

VIII. to ulnar side of ring-finger ; 

IX. to radial side of little finger. 

(be) Proper volar digital nerve (N. digitalis volaris proprius), 

X. to ulnar side of little finger. 

Find the muscular rami given off by this nerve to the 
muscles of the hypothenar eminence. 

Transverse Carpal Ligament (Ligamentum carpi transversum) (O. 

T. Anterior Annular Ligament). (Cf. Spalteholz, Figs. 363- 

365.) 

Contrary to statements in many books, this ligament is not 
directly continuous either with the fascia antibrachii or with the 




DISSECTION OF THE UPPER EXTREMI 

aponeurosis palmaris. Note its attachments ulna 
medialward. Study the relations of its deep and supe 
faces. What is the canal beneath it called and what stru 
pass through this canal ? 

Flexor Tendons and their Mucous Sheaths. (Cf. Spalteholz, Fig. 

see.) 

(a) Mucous sheath of common flexor tendons (vagina [mucosa] tendinum 
Mm. flexorum communium) (0. T. synovia! sheath). 

If uninjured by dissection thus far, insert a blow-pipe into sheath 
proximal to ligamentum carpi transversum and inflate. Study the 
exact relations to the flexor tendons in your cadaver and compare 
with text-book descriptions. (Cf. Fig. 37.) 

FIG. 37. 




Palmar synovial sheaths (vaginae tendinum), normal adult type. (From Poirier et Charpy, Trait6 
d'Anat. hum., Paris, 1901, 2 ed., t. ii. p. 190, Fig. 147.) 

(b) Mucous sheath of tendon of long flexor of thumb (vagina tendinis M. 

ftexoris pollicis longi). 

(c) Digital sheaths of the tendons (vaginae tendinum digitales). 

Note also the pairs of small folds extending between the first 
and second phalanges and the digital sheaths; these are the so- 
called "bands of union of the tendons" (vincula tendinum). They 
carry the blood-vessels to the tendons. 



102 LABORATORY MANUAL OF HUMAN ANATOMY 

Study the ligaments of the sheaths of the fingers (ligamenta 
vaginalia digitorum manus} and the accessory ligaments. Of the 
latter, examine (1) the ring-ligaments (ligamenta annularia digi- 
torum manus) and (2) the cruciate ligaments (ligamenta cruciata 
digitorum manus). (Spalteholz, Fig. 363.) 

Cut through these ligaments and open up the digital sheaths of 
the tendons. The vincula tendinum are well seen on raising the 
tendons from the phalanges. 
(d) Flexor tendons and their insertions. (Fig. 38.) 

Cut through the ligamentum carpi transversum by a vertical 
incision at its middle, thus opening the carpal canal (canalis carpi). 
Examine the arrangement of the flexor tendons and dissect each 
free from the vagina tendinum. Compare the arrangement found 
with the description in your systematic text-book. Note the rela- 
tion of these tendons to the central compartment of the palm. 

Examine carefully the insertions of the tendons of the various 
flexor muscles. Where and how are the tendons of the superficial 
flexor perforated by those of the deep flexor? What is meant by 
the chiasm of the tendons (chiasma tendinum) ? 

FIG. 38. 



Os metacarpale 




Tendon of the M. flexor digitorum subfimis 



M. lumbricalia 



Tendon of the M. flexor 
digitorum profundus 



The terminal parts of the flexor and extensor tendons of the right middle finger, seen from the radial 
side. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 323, Fig. 565. ) 

Follow the tendon of the M. flexor pollicis longus. Open the 
vagina tendinis and see how and where the tendon is inserted. 
What is its relation to the muscles of the thenar eminence 1 ? 

Lumbrical Muscles (Mm. lumbricales). 

Cut through the arcus volaris superficialis on the ulnar side 
distal from the deep volar ramus of the ulnar artery, and on the 
radial side at its junction with the superficial volar ramus of the 
radial artery. Beflect the arch distalward. Cut through the 
N. medianus at the level of the wrist and reflect it radialward and 
distalward, noting again its branches to the muscles of the thenar 
eminence and the two (radial) Mm. lumbricales. Cut through 
the M. flexor digitorum sublimis at middle of forearm and reflect 
it and its tendons distalward as far as possible. Examine thor- 
oughly the tendons of the M. flexor digitorum profundus and the 



DISSECTION OF THE UPPER EXTREMITY 103 

Mm. lumbricales. Study origin, insertion, form, position, action, 
and innervation of each of the four lumbrical muscles. Divide 
the M. flexor digitorum profundus in its muscular part in the 
forearm and reflect it far distalward, along with the Mm. lum- 
bricales. Take this opportunity to secure the branches of the 
ramus profundus of the ramus volaris manus of the N. ulnaris 
supplying the two (ulnar) lumbrical muscles. 

Short Muscles of Thumb and Little Finger. 

Study carefully the form, position, origin, insertion, action, 
and innervation of each of the following muscles : 

(a) Short abductor muscle of thumb (M. abductor pollicis brevis) (0. T. 

abductor pollicis). 

(b) Abductor muscle of little finger (M. abductor digiti quinti). 

(c) Short flexor muscle of little finger (M. flexor digiti quinti brevis). 

(d) Opposing muscle of thumb (M. opponens pollicis). 

(e) Short flexor muscle of thumb (M. flexor pollicis brevis). 

(f) Adductor muscle of thumb (M. adductor pollicis). 

(g) Opposing muscle of little finger (M. opponens digiti quinti). 

Deep Ramus of Volar Ramus of the Hand from the Ulnar Nerve (R. 
profundus R. volaris manus N. ulnaris). 

Study- 

(a) Muscular rami (rami musculares) to all muscles of palm lying ulnar- 
ward from tendon of M. flexor longus pollicis (except two radial 
Mm. lumbricales). 

Deep Volar Arch (Arcus volaris profundus) (O. T. Deep Palmar 
Arch). (See Fig. 34.) 

How is it formed! (Cf. Spalteholz, Fig. 460.) Compare its 
convexity with that of the superficial volar arch. With a colored 
pencil indicate its position on your own palm. Study carefully 
its relation to neighboring muscles and nerves. Cut through the 
M. adductor pollicis at its origin and reflect it. Follow out care- 
fully each of the four following branches : 

(a) Volar metacarpal arteries (Aa. metacarpeae volares). 

(aa) A. metacarpeae volaris I. 

(aaa) Branch to thumb (0. T. arteria princeps pollicis). 

(aab) Branch to radial side of index-finger (0. T. arteria 

radialis indicis). 

(ab) A. metacarpea volaris II. (0. T. first palmar interosseous), 

forward between second and third phalanges to join A. 
digitalis communis. 



104 LABORATORY MANUAL OF HUMAN ANATOMY 

(ac) A. metacarpea volaris III. (0. T. second palmar interosseous), 

forward between third and fourth phalanges to join A. 
digitalis communis. 

(ad) A. metacarpea volaris IV. (0. T. third palmar interosseous), 

forward between fourth and fifth phalanges to join A. 
digitalis communis. 

Note rami perforantes given off by each volar metacarpal 
artery. 

Study the formation of the volar carpal network (rete carpi 
volar e) (O. T. anterior carpal rete). 

DORSAL SURFACE AND RADIAL MARGIN OF FORE- 
ARM (FACIES DORSALIS ET MARGO RADIALIS 
ANTIBRACHII). 

The skin and superficial fascia with their nerves and blood- 
vessels have already been studied. The fat of the superficial 
fascia should now be completely removed and the deep fascia 
studied. 

Dorsal Portion of Deep Fascia of Forearm (Fascia antibrachii) . 

How is it attached above and below ! Note the relation of its 
deep surface to the extensor muscles. The dorsal ligament of 
the carpus (lig amentum carpi dor sale) (0. T. posterior annular 
ligament) is really a part of it. 

Superficial Muscles of Dorsum of Forearm. 

Dissect away the deep fascia on the dorsum of the forearm, 
with the exception of that portion of it near the elbow overlying 
and giving origin to muscles underneath. The ligamentum carpi 
dorsale should also be preserved. Isolate as far as possible and 
clean the surfaces of the following muscles : 

(a) Brachioradial muscle (M. brachioradialis) (0. T. supinator longus). 

(b) Long radial extensor muscle of carpus (M. extensor carpi radialis 

longus). 

(c) Short radial extensor muscle of carpus (M. extensor carpi radialis 

b rev is). 

(ca) Bursa M. extensoris carpi radialis brevis (Spalteholz, Fig. 
360). 

(d) Common extensor muscle of fingers (M. extensor digitorum com- 

munis ) . 

Study juncturae tendinum later. 

(e) Proper extensor muscle of fifth finger (M. extensor digiti quinti 

proprius) (0. T. extensor minimi digiti). 



DISSECTION OF THE UPPER EXTREMITY 105 

(f) Elbow muscle (M. anconaeus). 

(g) Ulnar extensor muscle of carpus (M. extensor carpi ulnaris). 



Vessels and Nerves on Dorsum of Forearm. 

Divide the M. extensor digitorum communis and M. extensor 
digiti quinti proprius at about the middle of their fleshy bellies 
and reflect proximalward and distalward. Find the muscular 
rami from the ramus profundus N. radialis innervating these 
muscles. Dissect out carefully 

(a) Dorsal interosseous artery (A. interossea dorsalis) (0. T. posterior 

interosseous artery). How does it arise? Follow its course 
and distribution. 

(aa) Recurrent interosseous artery (A. interossea recurrens) (0. 
T. posterior interosseous recurrent). 

(b) Arterial network about the elbow- joint (rete articular -e cubiti). 

Find the following tributaries : 
Above. 

(ba) A. collateralis ulnaris superior. 

(bb) A. collateralis ulnaris inferior. 
(be) A. collateralis media. 

(bd) A. collateralis radialis. 
Below. 

(be) A. recurrens ulnaris posterior. 

(bf) A. interossea recurrens. 

(bg) A. recurrens radialis. 
Ulnarward. 

(bh) Transverse branch fed by A. collateralis ulnaris inferior. 

(c) Terminal branch of volar interosseous artery (A. interossea volaris) 

(0. T. anterior interosseous). 

(d) Deep ramus of radial nerve (ramus profundus N. radialis). 

(da) Muscular branches (rami musculares). 

(db) Dorsal interosseous nerve (N. interosseus [antibrachii] dor- 

salis) (0. T. posterior interosseous). 



Deep Muscles of Dorsum of Forearm. 
Clean and study carefully 

(a) Supinator muscle (M. supinator) (0. T. supinator brevis). 

(b) Long abductor muscle of thumb (If. abductor pollicis longus) (0. T. 

extensor ossis metacarpi pollicis). 

(c) Short extensor muscle of thumb (M. extensor pollicis brevis) (0. T. 

extensor primi internodii pollicis). 

(d) Long extensor muscle of thumb (M. extensor pollicis longus) (0. T. 

extensor secundi internodii pollicis). 

(e) Proper extensor muscle of index-finger (M. extensor indicts proprius) 

(0. T. extensor indicis). 

Whence does each get its nerve-supply? 



106 



LABORATORY MANUAL OF HUMAN ANATOMY 



DORSUM OF WRIST AND HAND. 
Radial Artery and Veins. 
Study- 

(a) Radial artery (A. radialis). 

(aa) Dorsal carpal ramus (ramus car pens dor sails) (0. T. pos- 

terior radial carpal). 

(ab) First dorsal metacarpal artery (A. metacarpea dorsalis I.). 

(aba) Aa. digitales dor sales. 

(1) A. dorsalis pollicis ulnaris. 

(2) A. dorsalis indicis. 

(ac) Dorsal digital artery to radial side of thumb (A. dorsalis 

pol lids ra dia Us). 



FIG. 39. 



Tendon of the M. flexor digitorum sublim 
Tendon of the M. flexor digitorum profundus 

M. flexor carpi ulnaris - 

A. ulnaris 
N. ulnaris 

Ramus dorsalis manus 
of the N. ulnaris 

Discus articularis.- 

Capitulum ulnae 
Tendon of the 
M. extensor carpi ulnaris-? 




Lig. carpi volare 

Tendon of the M. palmaris longus 
N. medianus 

^.Tendon of the M. flexor carpi radialis 
^Tendon of the M. flexor pollicis longuc 
__ .Ramus volaris superficialis 
_A. radialis 

-.M. abductor pollicis longus 

-M. extensor pollicis brevis 
-Radius 

M. extensor carpi radialis longus 
'..M. extensor carpi radialis brevis 
M. extensor pollicis longus 



Tendon of the M. extensor digiti 
V. proprius 

Lig. carpi dorsale 

Cross-section of the distal extremity of the right forearm. Surface distal to the cut. 
(After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 621, Fig. 999.) 



Tendons of the Mm. extensor digitorum 
lommunis and extensor indicis proprius 



(ad) Dorsal carpal rete (rete carpi dorsale) (0. T. posterior carpal 

rete). 

(ada) Dorsal metacarpal arteries (Aa. metacarpeae dor- 
sales II., III., IV.) (0. T. dorsal interosseous 
arteries). 

Note how each of these divides into two dorsal 
digital arteries (Aa. digitales dorsales) for adja- 
cent margins of the second to the fifth finger. 

Find the artery passing directly from the ulnar 
side of the rete carpi dorsale towards the ulnar 
margin of the little finger. 
(b) Radial veins (Vv. radiales). 



Dorsal Ligament of Wrist (Ligamentum carpi dorsale) (O. T. Pos- 
terior Annular Ligament). 

How does it become attached radialward and ulnarward? 
How is the space beneath it subdivided ? To what are the various 
septa attached? Open up the following six compartments and 
study their contents. 



DISSECTION OF THE UPPER EXTREMITY 107 

First Compartment. 

Tendons of M. abductor pollicis longus and M. extensor pollicis brevis. 

Vagina tendinum Mm. abductoris longi et extensoris brevis pollicis. 
Second Compartment. 

Tendons of Mm. extensor carpi radialis longus et brevis. 

Vagina tendinum Mm. extensorum carpi radialium. 
Third Compartment. 

Tendon of M. extensor pollicis longus. 

Vagina tendinis M. extensoris pollicis longi. 
Fourth Compartment. 

Tendons of M. extensor digitorum communis and M. extensor indicis 
proprius. 

Vagina tendinum Mm. extensoris digitorum communis et extensoris 

indicis. 
Fifth Compartment. 

Tendon of M. extensor digiti quinti proprius. 

Vagina tendinis M. extensoris digiti V. 
Sixth Compartment. 

Tendon of M. extensor carpi ulnaris. 

Vagina tendinis M. extensoris carpi ulnaris. 

Note the variable extent of the vaginae tendinum into the dorsum 

manus. (Spalteholz, Fig. 369.) 

Tendons of Extensor Muscles of Fingers. (Spalteholz, Fig. 361 ; 
Poirier et Charpy, t. ii., Figs. 109, no.) 

Note the divergence of the tendons after leaving the osteo- 
fibrous canals at dorsum of wrist. At level of head of each meta- 
carpal bone find fibrous expansion going from deep surface of 
tendon, becoming adherent to capsula articularis, and inserted 
into base of first phalanx. At this level note union of process of 
deep palmar fascia with lateral sides of tendon. Note aponeu- 
rotic expansion at sides of each tendon over first phalanx and 
find insertions of Mm. interossei and Mm. lumbricales into these. 
Observe division of tendon (reinforced by " dorsal expansion") 
into three tongues of fibrous tissue, the middle one becoming 
directly inserted into base of phalanx II. ; the lateral tongues, 
stronger, go farther, become united over the second phalanx, 
and are inserted into the base of phalanx III. (ungual phalanx). 
Study the aponeurotic bridges (juncturae tendinum) uniting one 
tendon with its neighbor. Why is the independent movement of 
the ring-finger backward so limited ? 

In the thumb, the tendons of the two extensors are placed side 
by side at the level of the metacarpophalangeal joint and receive 
the same expansions of the palmar fascia and also interosseous 
muscles (represented here by the M. abductor pollicis brevis and 
the M. interosseus I.). 



108 



LABORATORY MANUAL OF HUMAN ANATOMY 



Note the exact behavior of the tendons of the M. extensor 
indicis proprius and the M. extensor digit! quinti proprius at 
and near their terminations. 



Dorsal Interosseous Nerve (N. Interosseus dorsalis) (O. T. Pos- 
terior Interosseous). 

Find the terminal filament of this nerve. To what structures 
is it related! What joints are innervated by it? 



FIG. 40. 



M. lumbricalis 



Aponeurotic expansion on 
ulnar side 




Tendon of M. ex- 
tensor commu- 
nis digitorum 

Slip to first 

phalanx 

_ Perforating 

fibres 



_ M. interosseus 



Tendons of the M. extensor communis digitorum: connections (deep surface). (From Poirjer et 
Charpy, Trait< d'Anat. hum., Paris, 1901, 2 ed., t. ii. p. 130, Fig. 109.) 

Transverse Ligament of the Heads of the Metacarpal Bones and the 
Interosseous Muscles. 

Place the volar surface of the hand upward and examine the 
transverse ligament of the heads of the metacarpal bones (liga- 



DISSECTION OF THE UPPER EXTREMITY 



109 



mentum capitulorum [ossium metacarpalium] transversum). 
Note that the Mm. lumbricales run volar and the Mm. interossei 
dorsal to this ligament. 

Study the form, position, origin, insertion, action, and inner- 
vation of 

(a) Volar interosseous muscles (Mm. interossei volares I., II., III.). 

(b) Dorsal interosseous muscles (Mm. interossei dor sales I.-IV.). 

Eeflect the radial head of the M. interosseus dorsalis I. A 
good dorsal view of the deep head of the M. flexor pollicis brevis 



V. mediana basilica -- s 



N. cutaneus anti- 
brachii medialis --- - 

N. / 

medianus ------ 7^ 

A. of the 
N. med.-- 
M. brach. --- 
M. pronat.. - 
teres 

M. palm. 
long. 

M. flex. _ 
sub. dig. 

A. collat. 
uln. sup. 

N. ulnaris - - 



M. flexor - - 
carpi ulnaris 



Bursa subcutanea olecrani 



FIG. 41. 

/ A. brachialis 
/ /- - V. mediana cephalica 




. . N. muscnlocutaneus 
Tendon of the 
_.M. biceps 
\ M. brachio- 

" " " radian's 
tTV " "N. radialis 
i-A.recurrens 
^ radialis 

-Capsula 

articularis 
-M. extensor 
carpi rad. 
longus 

- - -M. extensor 
carpi rad. 
brevis 

A. interosseus 

recurrens 

Common tendon of 
origin of extensors 



M. anconaeus 



Olecranon 



Transverse section of the left elbow (after Farabo3uf). The distal end of the humerus is seen intact. 
(From Poirier et Charpy, TraitS d'Anat. hum., Paris, 1899, 2 ed., t. i. p. 645, Fig. 655.) 

can now be obtained. How does this head arise? Where is it 
inserted? This part of the M. flexor pollicis brevis was desig- 
nated by Henle the M. interosseus volaris primus. 

The course of the tendon of the M. flexor radialis should now 
be followed and its exact insertion established. 



JOINTS. 

Elbow-joint (Articulatio cubiti). (Figs. 41, 42, and 43.) 

The muscles about the elbow may now be completely removed. 
Leave the M. supinator in position after removal of the others, 
in order that its exact origin, insertion, innervation, and mode 



110 



LABORATORY MANUAL OF HUMAN ANATOMY 



of action may be made out. It may then be cut away also. What 
bones are concerned in the formation of the elbow- joint? Note 
that the articulatio cubiti really includes three articulations : 

(a) Humero-ulnar articulation (articulatio humero-ulnaris) ; 

(b) Humeroradial articulation (articulatio humeroradialis) ; 

(c) Proximal radio-ulnar articulation (articulatio radio-ulnaris proxi- 

malis ) . 
Joints (a) and (b) are studied at this stage; joint (c), a little later. 

FIG. 42. 




Lig. 
coll. 
uln. 



Capsula articularis 
(anterior part) 



Humerqcoronoid 
fascicle 



.Olecranohumeral 
fascicle 



Ol ecranocoronoid 
fascicle (Cooper's 
ligament) 



Articulatio cubiti. (From Poirier et Charpy, Traite" d'Anat. hum., Paris, 1899, 2 ed., t. i. p. 641, 

Fig. 650.) 

Study carefully the form, position, and attachments of each 
of the following ligaments : 

(a) Joint-capsule (capsula articularis). 

(aa) Ulnar collateral ligament (ligamentum collaterale ulnare) (0. 

T. internal lateral ligament). 

(ab) Radial collateral ligament (ligamentum collaterale radiale) 

(0. T. external lateral ligament). 

Make a transverse cut across the anterior surface of the cap- 
sula articularis so as to open the joint. Examine the extent of 
the synovial membrane. Note the continuity of the cavities of 
the humero-ulnar and humeroradial articulations with that of 
the proximal radio-ulnar articulation, all forming one joint- 
cavity, that of the articulatio cubiti. (See Fig. 43.) 



DISSECTION OF THE UPPER EXTREMITY 



111 



Study the possible movements of the humeroradial and 
humero-ulnar articulations. 

Joint of the Hand (Articulatio manus). 

Dissect away the whole of the ligamentum carpi transversum 
and the ligamentum carpi dorsale. Reflect the flexor and ex- 
tensor tendons distalward, so as to leave the region of the wrist 
bare. Cut away the short muscles of the thenar and hypothenar 
eminences. 

FIG. 43. 




Labrum ,, 
falciforme" 



Articulatio cubiti, frontal section. (From Poirier et Charpy, Traite d'Anat. hum., Paris, 1899, 2 ed., t. L 

p. 644, Fig. 653.) 

Note that the joint of the hand is divisible into two chief 
parts : 

(a) Radiocarpal articulation (articulatio radiocarpea) (0. T. wrist- 

joint). 

(b) Intercarpal articulation (articulatio intercarpea) (0. T. carpal 

joints). 

ad (a) What bony articular surfaces are concerned in the radiocarpal articu- 
lation? Study carefully the following: 

(aa) Joint-capsule (capsula articularis) . 

(ab) Strengthening ligaments: 

(aba) Dorsal radiocarpal ligament (ligamentum radiocar- 

peum dorsale) (0. T. posterior ligament). 

(abb) Volar radiocarpal ligament (ligamentum radiocar- 

peum volare) (0. T. anterior ligament). 

(abc) Ulnar collateral ligament of carpus (ligamentum 



112 



LABORATORY MANUAL OF HUMAN ANATOMY 



collaterale carpi ulnare) (0. T. internal lateral 
ligament). 

(abd) Radial collateral ligament of carpus (ligamentum 
collaterale carpi radiate} (0. T. external lateral 
ligament). 

FIG. 44. 




V. Using the little 
finger as an axis 



JII. Using the middle 

finger as an axis 



I. Using the thumb 

as an axis 



I 
Supination Pronation 

Schema of pronation and of supination. 

On the right side of the figure are reproduced three tracings by the radius and the ulna in the 
movements of pronation and supination, taking as an axis the thumb (7.) , the middle finger (///.) , and 
the little finger ( V.) . (The larger curve belongs to the radius, the smaller to the ulna.) (From Poirier 
et Charpy, Traite d'Anat. hum., Paris, 1899, 2 ed., t. i. p. 658, Fig. 665.) 



(b) What bony articular surfaces are concerned in the intercarpal articu- 
lation? Study carefully the following: 

(ba) Joint-capsules (capsulae articular es) . 

(bb) Strengthening ligaments : 

(bba) Radiate ligament of carpus (ligamentum carpi ra- 

diatum}. 

(bbb) Dorsal intercarpal ligaments (Ligg. intercarpea dor- 

salia}. 



DISSECTION OF THE UPPER EXTREMITY 



113 



(bbc) Volar intercarpal ligaments (Ligg. intercarpea vo- 

laria) (0. T. palmar intercarpal). 

(bbd) Interosseous intercarpal ligaments (Ligg. intercar- 

pea interossea). 

To examine these ligaments carefully the ulnar and radial collateral 
ligaments of the carpus and the dorsal intercarpal ligaments should be 
cut through. 

In this connection study also the articulation of the pisiform 
bone (articulatio ossis pisiformis), examining the following: 

FIG. 45. 

Art. raclio-ulnaris distalis 



Radiocarpal interspace 
Intercarpal interspace 







Discus articularis 



Os triquetrum 



Carpometacarpal - J*i&t^ii8!a$i;!^ _ _ Lig. carpometacarpale 

interspace ^^ilJ^w^d^J/M/v! ^** *\^^^^ .min. , il interosseum 



Lig. basis ( os. meta- 
carp.) interosseum 



Frontal section of the radiocarpal, carpal, and carpometacarpal joints. (From Poirier et Charpy, 
Trait6 d'Anat. hum., Paris, 1899, 2 ed., t. i. p. 660, Fig. 667.) 



(a) Joint-capsule (capsula articularis}. 

(b) Strengthening ligaments: 

(ba) Ligamentum pisohamatum. 

(bb) Ligamentum pisometacarpeum. 

How are these related to the tendon of the M. flexor carpi ulnaris, 
and of what importance are they? 

Of what movements is the hand capable at the radiocarpal 
articulation? In how far are these movements favored or in- 
creased by means of the intercarpal articulation? What muscles 

8 



114 LABORATORY MANUAL OF HUMAN ANATOMY 

are concerned in flexion, extension, abduction, and adduction of 
the hand? Of what especial advantage are the multiple bones 
and joints of the carpus? 

Radio-ulnar Joints. (See Figs. 44, 45, and 46.) 
These joints consist of 

(a) Proximal radio-ulnar articulation (articulatio radio-ulnaris proxi- 
malis) (0. T. superior radio-ulnar). 

FIG. 46. 



Tend. M. bicipitis 

-Chorda obliqua (Lig. of Weitbrecht) 



.Ligamentum interosseum 



-Orifice for the A. interossea volaris 



The interosseous membrane of the forearm, volar surface. (After Poirier et Charpy, 
Traite d'Anat. hum., Paris, 1899, t. i. p. 655, Fig. 664.) 

(&) Distal radio-ulnar articulation (articulatio radio-ulnaris distalis) (0. 

T. inferior radio-ulnar). 
(c) Interosseous membrane and oblique cord (membrana interossea anti- 

brachii et chorda obliqua). 

To expose the ligaments, the muscles must be completely re- 
moved from the dorsal and volar surfaces of the forearm. 

(a) Proximal radio-ulnar joint. 

What bony surfaces are concerned? Study carefully the annular 



DISSECTION OF THE UPPER EXTREMITY 115 

ligament of the radius (ligamentum annulare radii) (0. T. orbicu- 
lar ligament) and the sacciform recess (recessus sacciformis). 

(b) Distal radio-ulnar joint. 

What bony surfaces are concerned? Study carefully 

(ba) Joint-capsule (capsula articularis}. 

(bb) Articular disk (discus articularis) (0. T. triangular fibro- 

cartilage). 
(be) Saccular recess (recessus sacciformis). 

(c) Interosseous membrane and oblique cord. 

Study exact form and attachments. What vessels and nerves are 
related to the interosseous membrane? 

In what movements are the radio-ulnar articulations con- 
cerned! Study carefully the movements of pronation and supi- 
nation (a) when the forearm is extended, (b) when it is flexed. 
What muscles are concerned in these movements ? 

Saw through the ulna at the junction of its distal and middle 
thirds ; cut through the membrana interossea. Draw the distal 
fragment of the ulna medialward ; open the recessus sacciformis. 
The proximal surface of the discus articularis can be seen and 
its attachments carefully examined. 

Carpometacarpal Joints (Articulationes carpometacarpeae). 

How many of these are there ? What bony surfaces are con- 
cerned in their formation? In order to examine these joints 
thoroughly, remove the Mm. interossei from the metacarpal 
bones and detach the tendons of the flexor muscles and the Mm. 
lumbricales from the fingers. Do not disturb the extensor ten- 
dons at present. Clean the carpometacarpal and the intermeta- 
carpal ligaments carefully. Study in the four ulnar carpometa- 
carpal articulations the following : 

(a) Joint-capsules (capsulae articular es] . 

(b) Strengthening ligaments : 

(ba) Dorsal carpometacarpal ligaments (ligamenta carpometacar- 

pea dorsalia). 

(bb) Volar carpometacarpal ligaments (ligamenta carpometacar- 

pea volaria). 

Note the special carpometacarpal joint for the thumb 
(articulatio carpometacarpea pollicis). Study its capsula 
articularis. 

Intermetacarpal Joints (Articulationes intermetacarpeae). 

These joints are amphiarthroses. What is an amphiarthro- 
sis ? Study 

(a) Joint-capsules (capsulae articulares) . 

(b) Strengthening ligaments: 



116 LABORATORY MANUAL OF HUMAN ANATOMY 

(ba) Dorsal ligaments of basal extremities of metacarpal bones 

(Ligg. basium [ossium metacarpalium] dorsalia). 

(bb) Volar ligaments of basal extremities of metacarpal bones 

(Ligg. basium [oss. metacarp.] volaria). 

(be) Interosseous ligaments of basal extremities of metacarpal 
bones (Ligg. basium [oss. metacarp.] interossea). These 
fill up the spatia interossea metacarpi and can be studied 
to better advantage later, when the bases of the metacarpal 
bones are separated from one another. 

Before leaving the joints of the carpus and metacarpus, the 
synovial membranes and articular surfaces of the joint-cavities 
should be carefully reviewed. (See Fig. 45.) Which joint-cavi- 
ties are independent? Which communicate? Detach the meta- 
carpus from the carpus and examine the articular surfaces. 
Then separate the various bones of the carpus and metacarpus 
from one another in order to see the extent of the various inter- 
osseous ligaments and articular surfaces. 

Study the possible movements in the various joints under 
examination. What muscles are especially concerned in the 
various movements ? 

Metacarpophalangeal Joints (Articulationes metacarpophalangeae). 

These five joints are arthrodiae. What is an arthrodia? 
Study- 

(a) Joint-capsules (capsulae articular es] . 

(b) Strengthening ligaments: 

(ba) Collateral ligaments (ligamenta collateralia) , one radial and 

one ulnar for each joint. 

(bb) Volar accessory ligaments (ligamenta accessoria volaria) (0. 

T. palmar ligaments). 

(c) Transverse ligaments of the heads of the metacarpal bones (Ligg. 

capitulorum [oss. metacarpalium] transversa). These have already 
been examined (vide supra). 

Eaise the extensor tendon from the dorsal aspect of each 
joint and note the absence of dorsal ligaments, their place being 
taken by the extensor tendon. 

Of what movements is each metacarpophalangeal joint capa- 
ble ? What are the muscles concerned in each case for the differ- 
ent joints? 

Joints of the Fingers (Articulationes digitorum manus). 

Note that the thumb has one, the other digits two ginglymi. 
What is a ginglymus ? Study 



DISSECTION OF THE UPPER EXTREMITY H7 

(a) Joint-capsule (capsula articularis) . 

(b) Strengthening ligaments (ligamenta collateralia), one ulnar, one 

radial (0. T. lateral ligaments). 

What muscles are concerned in flexion and in extension of each of these 
joints ? 

Review the bones of the upper extremity. 



Part II 

DISSECTION OF THE LOWER EXTREMITY 



LOWER EXTREMITY 

Introductory. 

ON the surfaces of the lower extremity mark out the regions 
(regiones extremitatis inferioris). Make four drawings indi- 
cating these, one anterior, one posterior, one medial, and one 
lateral. Make use of Figs. 1 and 2 (pp. 43 and 44). 

In the thigh (femur) observe the general cylindrical shape, 
tapering distalward, the prominence in the middle line of the 
thigh in front due to the M. rectus femoris, and medial from this 
another due to the M. vastus medialis, extending distalward to 
the knee-cap. Note the direction of the streams of hairs (flumina 
pilorum). 

At the knee (genu) observe the prominent knee-cap (patella). 
In the leg (crus) note the general shape and the lateral and 
medial prominences near the ankle (malleoli later alls et me- 
dialis). 

In the foot (pes) observe the heel (calx) behind, constituting 
part of the ankle (tarsus) ; anteriorly, the toes (digiti) ; and 
between the ankle and the toes, the metatarsus. Among the 
digits distinguish- 
ed First or great toe (digitus primus, or hallux). 

(b) Second toe (digitus secundus). 

(c) Third toe (digitus tertius). 

(d) Fourth toe (digitus quartus). 

(e) Fifth or little toe (digitus quintus). 

How many phalanges has each digit? Examine the nails 
(ungues), and distinguish (a) root of nail (radix unguis), (b) 
free margin (mar go liber), (c) covered margin (mar go occultus), 
(d) semilunar white area (lunula). 

On the lateral surface of the lower extremity (fades later- 
alis) observe the hip (coxa) and thigh (femur), with the iliac 
crest (crista iliaca) above. Note the general configuration; 
observe the depression over the trochanter major at the upper 
extremity of the thigh-bone. On the lateral surface of the knee 
observe the prominent fold of skin covering the tendon of the 
biceps muscle, and anterior to this the fold covering the iliotibial 
band of the fascia. At the ankle the lateral malleolus (malleolus 
lateralis) is prominent, with a depression (fossa retromalleo- 

121 



122 LABORATORY MANUAL OF HUMAN ANATOMY 

laris) behind it. In the foot note that the lateral margin (mar go 
later alis) rests on the floor when the body is erect. 

Examine the posterior surface (fades posterior) of the lower 
extremity. Observe the prominence of the buttocks (dunes or 
nates), separated from each other by the crena ani and from the 
thigh by the gluteal fold (sulcus glutaeus) ; behind the knee is 
the popliteal fossa (fossa poplitea). Examine its boundaries and 
extent. In the leg note the prominent calf (sura), and lower 
down the prominence due to the tendon of the calf muscles. In 
the sole of the foot (plant a) observe the grooves in the skin (sulci 
cutis) and the ridges (cristae cutis) between. Observe the arch 
of the foot : it is higher on the medial than on the lateral margin. 
Note the ball of the great toe and the eminence of the little toe. 

On the medial surface (fades medialis) of the lower extrem- 
ity, observe the prominence due to the M. vastus medialis in the 
thigh, that due to the malleolus medialis at the ankle, and the 
curved medial margin of the foot (mar go medialis pedis). 

After inspection the student should resort to palpation of 
these parts. In addition to what has been mentioned above, note 
the groove at the groin (sulcus inguinalis) and the depression 
in the subinguinal region corresponding to a deeper triangle 
(fossa Scarpae major, trigonum femorale) (0. T. Scarpa's tri- 
angle). Can you feel the superficial lymph-glands (lympho- 
glandulae subinguinales superfidales) ? Note the mobility of the 
skin over the patella, due to a bursa (bursa praepatellaris sub- 
cutanea). Feel the ligament of the patella (tig amentum pa- 
tellae) and note the mobility of the skin over it (bursa infra- 
patellaris subcutanea). Flex and extend the knee-joint. What 
are the limits of movement? Feel the line of the joint during 
the movement. Palpate the condyles of the femur and of the 
tibia. Locate the tuberosity of the tibia and note the mobility of 
the skin over it (bursa subcutanea tuber ositatis tibiae). Feel the 
anterior crest of the tibia. How much of it is immediately sub- 
cutaneous ? Feel the medial surface of the tibia and the tendons 
of the extensor muscles of the foot. In the front of the foot find 
the rounded bony prominence of the anterior end of the heel- 
bone (calcaneus), three or four centimetres anterior to the malle- 
olus medialis. Just anterior to this note the depression indi- 
cating the position of Chopart's transverse joint of the ankle 
(articulatio tarsi transversa [CJioparti]) . 

Run the finger along the iliac crest. Feel the sciatic tuber- 
osity (tuber iscMadicum) and also the greater trochanter (tro- 
chanter major) ; note the mobility of the skin over the latter 



DISSECTION OF THE LOWER EXTREMITY 123 

(bursa subcutanea trochanterica). Draw the shortest possible 
line on the surface from the tuber ischiadicum to the spina 
iliaca anterior superior and note the relation which the upper 
extremity of the trochanter major bears to this line. Palpate 
the structures forming the boundaries of the popliteal fossa. 
Note the mobility of the skin over the malleoli (bursa subcutanea 
malleoli later alls et medialis). Feel the tendons in the retro- 
malleolar fossa. Palpate the various bony prominences that can 
be felt about the ankle and foot, and identify each by comparison 
with the skeleton. 

GLUTEAL EEGION (REGIO GLUTAEA). 

Make the following incisions (see Fig. 3) : 

(1) From the spina iliaca posterior superior along the crista iliaca as 

far forward as possible. 

(2) From the posterior extremity of this incision obliquely downward and 

medialward to the middle line of the sacral region, then vertically 
downward to the tip of the coccyx. 

(3) From the tip of the coccyx downward and lateralward over the back 

of the thigh, intersecting the sulcus glutaeus at its middle point, 
and terminating a little below the upper third of the thigh. 

The flap of skin thus formed should now be reflected lateralward, 
leaving intact the fat immediately beneath. There is now ex- 
posed to view- 
Superficial Fascia. 

Note the abundance of fat. How does the amount of fat 
contained compare in the male and female? Observe its tough, 
fibrous character over the tuber ischiadicum. This fascia should 
now be removed by blunt dissection. Find the following : 

Nerves. (Fig. 47.) 

(a) Middle nerves of buttock (Nn. clunium medii). These pierce the 
glutaeus maximus and the deep fascia in a line passing from the 
spina iliaca posterior superior to the tip of the coccyx. 

(&) Superior nerves of buttock (Nn. clunium superior es], crossing the 
crista iliaca at a point corresponding to the lateral limit of the 
attachment of the musculus sacrospinalis to the os ilium. 

(c) Lateral cutaneous ramus of iliohypogastric nerve (ramus cutaneus 

lateralis nervi iliohypogastrici). It generally crosses the iliac 
crest opposite a tubercle projecting from its outer lip, about two 
and one-half inches dorsal to the spina iliaca anterior superior. 

(d) Lateral cutaneous ramus of last thoracic nerve (ramus cutaneus 

lateralis N. thoracalis 7.) (0. T. last dorsal nerve). This nerve 
crosses the iliac crest a short distance anterior to the preceding. 



124 LABORATORY MANUAL OF HUMAN ANATOMY 



FIG. 47. 

Nn. clunium medii Nn. clunium superiores 



Kami perineales 



Twigs of the N. cutaneus femoris ^ 
posterior 



Ramus cutaneus of the N. obturatorius 




Twigs of the N. cutaneus 
femoris lateralis 



Nn. clunium inferiores 



N. cutaneus femoris posterior 
shining through the fascia lata 



\Twigs of the N. cutaneus 
/ femoris lateralis 



Twigs of the N. cutaneus surae 
lateralis 



Ramus cutaneus cruris medialis of the_ 
N. saphenus 



The cutaneous nerves of the gluteal region and on the posterior side of the thigh. (After Toldt, 
Anat. Atlas, Wien, 1903, 3 AufL, p. 849, Fig. 1286.) 



DISSECTION OF THE LOWER EXTREMITY 125 

(e) Cutaneous twigs from the posterior cutaneous nerve of the thigh 

(N. cutaneus femoris posterior) (O. T. cutaneous 
branches of small sciatic), passing around the lower 
border of the glutaeus maximus. 

(ea) Inferior nerves of buttock (Nn. clunium inferior es}. 

(eb) Perineal branches (rami perineales). 

(f) Posterior branches of lateral cutaneous nerve of thigh (N. cuta- 

neus femoris lateralis) (0. T. external cutaneous). 

These nerves should be traced as far as possible and their 
distribution carefully noted. 

Deep Fascia. 

Remove the remaining portion of the superficial fascia, pre- 
serving the nerves, and expose the deep fascia. 

Notice the general character of this fascia anteriorly, where 
it covers the M. glutaeus medius, and compare it in general 
characteristics with that portion of the fascia covering the 
M. glutaeus maximus. After having made a careful study of 
this fascia, remove it in a continuous layer from above down- 
ward, after having rendered the muscle tense beneath by ro- 
tating the thigh medial ward. The borders of the muscle should 
be carefully defined; note that the thin fascia covering the 
latter becomes continuous with the dense pearly aponeurosis 
covering the muscle immediately anterior to it. In dissecting 
away this fascia, cut always in the direction of the muscle fibres. 

Glutaeus Maximus Muscle (M. glutaeus maximus). 

Note carefully the form, position, origin, insertion, action, 
and innervation of this muscle. What is the relation of the 
muscle to the dense fibrous band (tractus iliotibialis) passing 
from the ilium to the tibia? How does the size of this muscle in 
man compare with that in other animals? After having care- 
fully examined and drawn this muscle, the student may reflect 
it in the following manner : The two borders of the muscle should 
be freed and the hand passed under the muscular mass. Detach 
the muscle from its attachment to the ilium. Proceed cautiously 
as the upper margin of the greater sacrosciatic foramen (fora- 
men ischiadicum ma jus) is approached and avoid the gluteal ves- 
sels as they pass through this opening. Secure these and detach 
the muscle from the side of the sacrum, exposing the piriform 
muscle (M. piriformis) as it emerges from the pelvis. Separate 
the muscular fibres from the ligamentum sacrotuberosum (0. T. 
great sacrosciatic ligament) and the side of the coccyx, avoiding 



126 LABORATORY MANUAL OF HUMAN ANATOMY 

the Nn. clunium inf eriores in order that they may later be traced 
to their source. The few coccygeal arteries passing through the 
ligamentum sacrotuberosum may be sacrificed. The muscle can 
now be partially reflected, but is still attached by blood-vessels 
and nerves entering its under surface. These should now be 
carefully cleaned. Having studied these last structures, they 
may be cut away, leaving a small piece of muscle connected to 
each. The whole muscle may then be reflected and its insertion 
examined. Clean and study the following : 

Bursae. (Vide Spalteholz, Figs. 385, 386.) 

(a) Bursa trochanterica M. glutaei maximi. 

(b) Bursa ischiadica M. glutaei maximi. 

(c) Bursae glutaeofemorales. 

Muscles. 

(a) Gluteus medius muscle (M. glutaeus medius). 

(b) Piriform muscle (M. piriformis). Note the relation it bears to 

the foramen ischiadicum ma jus. 

(c) Tendon of obturator internus muscle (M. obturator internus), pass- 

ing through the foramen ischiadicum minus and having the Mm. 
gemelli superior and inferior above and below it. 

(d) Quadratus femoris muscle (M. quadratus femoris). 

(e) Smallest adductor muscle (M. adductor minimus) (0. T. upper 

adductor magnus). 
(/) Tendon of the obturator externus muscle (M. obturator externus). 

Blood-vessels. (Fig. 48.) 

(a) Above the M. piriformis: 

(aa) Superior gluteal artery (A. glutaea superior}. 

(aaa) Upper ramus (ramus superior). 

(aab) Lower ramus (ramus inferior). 

(ab) Superior gluteal veins (Vv. glutaeae superior -es). 

(b) Below the M. piriformis: 

(ba) Inferior gluteal artery (A. glutaea inferior) (0. T. sciatic 

artery). 

(baa) Coccygeal branch, passing inward between the 

greater and lesser sacrosciatic ligaments to reach 
the integument and fascia in the region of the 
coccyx. Some twigs derived from this have 
already been cut in reflecting the muscle. 

(bab) Companion artery of the great sciatic nerve (A. 

comitans N. ischiadici). 

(bac) Artery to the quadratus femoris. This artery will 

serve as a guide for the nerve to this muscle in 
the further dissection. 

(bb) Inferior gluteal veins (Vv. glutaeae inf eriores). 

(be) Internal pudendal artery (A. pudenda interna). The pudic 
vessels can be seen emerging from the pelvis through the 
foramen ischiadicum ma jus and immediately re-enter- 
ing through the foramen ischiadicum minus. No 



DISSECTION OF THE LOWER EXTREMITY 



127 



branches of these vessels are found at this stage of the 
dissection. What is the canal of Alcock? 

(bd) Terminal branches of the medial circumflex artery (A. cir- 
cumflexa femoris medialis). What is the "crucial anas- 
tomosis" ? 

FIG. 48. 



A. glutaea 
superior 




A. perforans 
prima 



r 

Arteries of the gluteal region. The Mm. glutaeus max. and med. are, in great part, removed. (After 
Gegenbaur, Lehrb. der Anat. des Mensch., Leipzig, 1899, 7 Aufl., Bd. il. p. 285, Fig. 545.) 

Nerves. (Fig. 49.) 

(a) Above the M. piriformis: 

(aa) Superior gluteal nerve (N. glutaeus superior}. 

(b) Below the M. piriformis: 

(ba) Great sciatic nerve (TV. ischiadicus) . This nerve often 
divides into two branches (N. peronaeus communis and 
N. tibialis) over the piriformis muscle. The nerve sup- 
plying the M. obturator internus and M. gemellus su- 
perior will be found lying just lateral to the pudic 
vessels. It rests upon the base of the spina ischiadica. 
To expose the nerve to the quadratus femoris and gemel- 
lus inferior, reflect the gemelli muscles under which it 
runs. When traced as far as the gemellus inferior exer- 
cise great care and avoid injury to the twig passing into 



128 



LABORATORY MANUAL OF HUMAN ANATOMY 



this muscle. The quadratus femoris may now be reflected 
by detaching it from the femur and turning it towards 
the ischial tuberosity. The nerves supplying these mus- 
cles are derived from the tibial nerve (N. tibialis), a 
branch of the N. ischiadicus. 

FIG. 49. 



M. glutaeus max._ 



N. glutaeus sup. --| ^ 

9 \ 



Lig. sacrotuberosum- - 



N. pudendus 



Ramus perineal, 

N. cut. fern. 

post. 




M. glutaeus min. 
- -- M. tensor fasc. lat. 

M. piriformis 



N. ischiadicus 
- M. quad. fern. 

-M. glutaeus max. 



N. cut. fern, post 



Nerves of the gluteal region (after Hirschfeld, simplified). (From Poirier et Charpy, Trait6 d'Anat. 
hum., Paris, 1899, t. iii. p. 1111, Fig. 580.) 

(bb) Posterior cutaneous nerve of thigh (N. cutaneus femoris 
posterior] (0. T. small sciatic). 

(bba) Inferior nerves of buttock (Nn. clunium infe- 

r iores ) . 

(bbb) Perineal branches (rami perineales). 

(be) Pudendal nerve (N. pudendus) (0. T. internal pudic 

nerve). 
(bd) Inferior gluteal nerve (N. glutaeus inferior). 

Mm. Glutaei Medius et Minimus and Adjacent Structures. 

The M. glutaeus medius should be reflected after a careful 
study has been made of the preceding structures. Eotate the 



DISSECTION OF THE LOWER EXTREMITY 129 

thigh lateralward. Pull the M. glutaeus maximus well outward 
and divide its aponeurosis of insertion downward for a distance 
of five to seven centimetres. Grasping the cut edge of the fascia 
lata just separated from the M. glutaeus maximus, pull it out- 
ward and dissect in the interval between it and the M. glutaeus 
medius. By traction upon this band the deep surface of the 
tensor muscle of the fascia lata (M. tensor fasciae latae) (0. T. 
tensor vaginae femoris) may be exposed. It is covered by a layer 
of fascia. The student should now find 

(a) Terminal branch of superior gluteal nerve, piercing the anterior bor- 

der of the M. glutaeus minimus and entering the M. tensor fasciae 
latae. 

(b) Ascending branch of lateral circumflex artery (ramus ascendens A. 

circumflexae femoris lateralis). 

Separate the M. glutaeus medius from the M. glutaeus mini- 
mus by passing the fingers between their posterior borders. 
When completely isolated, divide the M. glutaeus medius five 
centimetres above the trochanter major and reflect the two parts 
upward and downward respectively. Carefully preserve the 
vessels and nerves between the two muscles and clean them thor- 
oughly. What vessels and nerves are exposed? Trace each to 
its termination. Can you find 

(a) Bursa trochanterica M. glutaei medii posterior? 

(b) Bursa trochanterica M. glutaei medii anterior? 

Where is the bursa M. piriformis? 

Detach the M. glutaeus minimus from its origin and reflect it 
downward. Observe the capsular ligament of the hip-joint (cap- 
sula articularis) . Where is the bursa trochanterica M. glutaei 
minimi ? Find the reflected head of the M. rectus femoris. What 
is the action of the muscles supplied by the superior gluteal 
nerve I 



POPLITEAL SPACE (FOSSA POPLITEA). 

Before beginning the dissection, review the surface anatomy 
of this space, noting 

(a) Lateral hamstring, formed by the biceps muscle. 

(b) Medial hamstring, formed by the tendons of the semitendinosus and 

semimembranosus muscles. 

(c) Tendon of adductor magnus muscle. Can you trace it as far down- 

ward as the adductor tubercle 1 ? In what position of the leg can 
this tendon be outlined most easily? 



130 LABORATORY MANUAL OF HUMAN ANATOMY 

(d) Epicondyles of femur. Which is the more prominent? 

(e) Line of the knee-joint. Flex and extend the leg to render this study 

easier. 
(/) Head of fibula (capitulum fibulae). Determine its relation to the 

tibia and femur. 
(g) Position of common peroneal nerve (TV. peronaeus communis). What 

relation does it bear to the lateral hamstring muscle 1 ? 

Skin and Superficial Fascia. 

Make an incision in the middle line of the posterior surface 
of the thigh through the popliteal fossa from a point ten or 
twelve centimetres above the bend of the knee to a point ten 
centimetres below it. Two transverse incisions should next be 
made, one at each end of the vertical incision, and the flaps 
formed reflected medialward and lateralward respectively. (See 
Figs. 3 and 52.) Make the parts tense by means of a large block 
placed under the knee. 

Note the general characteristics of the superficial fascia. Re- 
move this fascia piecemeal, examining the following : 

(a) Twigs of posterior cutaneous nerve of thigh (N. cutaneus femoris 

posterior) (0. T. small sciatic). In what part of this space does 
the terminal branch of this nerve pierce the deep fascia? 

(b) Small saphenous vein (V. saphena parva). Preserve intact this 

vein and any of its radicles that you may find. What is the femoro- 
popliteal vein (V. femoropoplitea) ? (Vide Spalteholz, Fig. 509.) 

(c) Superficial lymphatic vessels (vasa lymphatica superficialia) . (Vide 

Fig. 50.) 

Boundaries of Fossa Poplitea. 

The fossa poplitea is diamond-shaped. Its roof is formed by 
the deep fascia (fascia cruris), sometimes called the " popliteal 
fascia. " Note carefully the density of this fascia. After the 
fascia has been studied, incise it in the median line and reflect 
each way. Care should be exercised to avoid injuring the com- 
municating fibular nerve (N. communicans peronaeus) and a 
bursa situated between the M. semimembranosus and the medial 
head of the M. gastrocnemius. 

Next study the lateral boundaries : 

(a) Biceps muscle (M. biceps femoris). 

(b) Semitendinosus muscle (M. semitendinosus) . 

(c) Semimembranosus muscle (M. semimembranosus). 

(d) Gastrocnemius muscle (M. gastrocnemius). 

(da) Lateral head (caput laterale). 

(db) Medial head (caput mediale). 

(e) Plantaris muscle (M. plantaris). 



DISSECTION OF THE LOWER EXTREMITY 



131 



FIG. 50. 



Scrotum 



Lymphoglandulae popliteae , 



f_Vas lymphaticum profundum 



F-. Fossa poplitca 



V. saphena parva 



The superficial lymphatic vessels of the posterior side of the lower extremity and the deep lymphatics 
of the popliteal space. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 709, Fig. 1091.) 



132 



LABORATORY MANUAL OF HUMAN ANATOMY 



The exposed parts of each of these muscles should be care- 
fully cleaned. 

Eemove the fat of the fossa, carefully dissecting out its con- 
tents (vide infra). 

In cleaning the structures in the fossa, avoid disturbing their 
relations. 



FIG. 51. 



Tend. M. quadriceps fern. 
Patella 



Fascia lata 



.Strat. synoviale 



M. quadriceps fern. 
Lig. patell. prop. med. . % 



Femur...- 




M. quadriceps fern, et 
M. tensor fasciae latae 



Condyl. med.... 



M. gracilis - 

N. saphenamag..-' 
M. sartorius 



Cap. art. over the cond. med. 

M. semimemb. 

M. semitend. i 
M. gastroc. (caput med.) 



- Cond. lat. 



Cap. art. over 
the cond. lat. 



M. gastroc. 
(caput lat.) 

. M. biceps fern. 



N. peronaeus com. 



N. tibialis 



V. poplitea 
A. poplitea 

Lymphogland. poplit. 



Cross-section of the articulatio genu, passing through the middle of the patella. Right side, seg- 
ment distal to the line of section (P. Fredet). (From Poirier et Charpy, Traite d'Anat. hum., Paris, 
1901, 2 ed., t. ii. p. 242, Fig. 180.) 



Contents of Fossa Poplitea. (Figs. 51-53.) 

Nerves. (Figs. 51 and 52.) 

(a) Tibial nerve (N. tibialis) (0. T. internal popliteal nerve). What 

is its position in the fossa? 

(aa) Muscular branches (rami muscular es). Dissect each mus- 
cular branch out carefully and trace into the muscle. 
(db) Articular branch (ramus articularis) . 
(ac) Medial cutaneous nerve of the calf (N. cutaneus surae 

medialis) (0. T. nervus communicans tibialis). 
Interosseous nerve of the leg (N. interosseus cruris). 



DISSECTION OF T1IK LOWER EXTREMITY 



133 



(b) Common peroneal nerve (N. peronaeus communis) (0. T. external 

popliteal). 

(ba) Muscular branches (rami musculares). 

(bb) Lateral cutaneous nerve of calf (N. cutaneus surae lat- 

er alls}. 

(be) Peroneal anastomotic branch (ramus anastomoticus pero- 
naeus) (0. T. nervus communicans fibularis). 

(c) Posterior cutaneous nerve of thigh (N. cutaneus femoris posterior) 

(0. T. small sciatic nerve). This nerve is found directly under- 
neath the fascia. Its branches have already been referred to. 

(d) A branch of the obturator nerve (N. obturatorius) descends into 

the space in close relation to the artery. 



FIG. 52. 



M. adductor magnus 



N. tibialis 



Ramns muscularis 



M. semimembranosus 
M. semitendiuosus 



A. poplitea 
V. poplitea 

M. vastus medialis 
A. genu sup. med. 

Fossa poplitea 

Twig to the 

A. poplitea 

A. suralis medialis 



Kami musculares 

Ramus articularis 
A. genu inf. med. 



M. gastrocneralus 
(caput mediale) 



M. soleus 
Tendon of the M. 
plantaris 

N. cut. snrae med. 
M. popliteus 




M. bicipitis 
femoris 



Caput 
longum 
Caput 
breve 
N. peronaeus mm- 

munis 
Ramus artieularis for 

the knee-joint 
Ramus muscularis 



A. genu sup. lat. 
N. cut. surae lat. 
A. genu nit-din. 



M. plantaris 
A. suralis lateralis 



. peronaeus communis 

A. genu inf. lat. 

riK-in'iiiius f caput 
laterale) 

Arcus tendincus M. ->l'i 
Ramus anast. peronaeus 



N. suralis 

The popliteal spare. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 631, Fig. 1010, and (3 lAufl ) p. 842, 
Fig. 1278, and Cunningham, Manual of Prac. Anat., Phila., 1903, 3d ed., vol. i. p. 1 - 1. H 

Arteries. (Figs. 52 and 53.) 

(a) Popliteal artery (A. poplitea). Note especially the n-latu 

this artery bears to the structures contained in the sj >:< 



134 



LABORATORY MANUAL OF HUMAN ANATOMY 



and dissect out its branches. Determine accurately the 
vessels which enter into the anastomosis about the knee. 

(aa) Lateral superior artery of knee (A. genu superior lateralis) 

(0. T. superior external articular artery). 

(ab) Medial superior artery of knee (A. genu superior medialis) 

(0. T. superior internal articular artery). 

(ac) Middle artery of knee (A. genu media) (0. T. azygos ar- 

ticular artery). 

(ad) Lateral inferior artery of knee (A. genu inferior lateralis) 

(0. T. inferior external articular artery). 

(ae) Medial inferior artery of knee (A. genu inferior medialis) 

(0. T. inferior internal articular artery). 

(af) Sural arteries (Aa. surales). 

What is the rete articular e genu? What is the rete patellae? 



FIG. 53. 



A. genu sup. med. 



A. genu inf. med. 




Art. nutric. tib.---- 
A, rec. tib. med ' 

A. tib. post. 



_A. recurrens tib. post. 



_A. tibialis post. 



A. peronaeus 



Schema of the A, poplitea, (From Poirier et Charpy, Traite d'Anat. hum., Paris, 1901, 2 eel., t. ii. 

p. 830, Fig. 448.) 

Veins. 

(a) Popliteal veins (Vv. popliteae). 

(aa) Small saphenous vein (V. saphena parva). 

(ab) Articular veins of knee (Vv. articulares genu). 

(ac) Lateral companion vein (V. comitans lateralis). 

(ad) Medial companion vein (V. comitans medialis). 



DISSECTION OF THE LOWER EXTREMITY 135 

Note especially the relation of the vein to the artery in the 
upper and lower parts of the fossa. Incise the vein longitudinally 
and search for valves. Are any present? 
Lymphatics. (Vide Fig. 50.) 

(a) Popliteal lymph-nodes (lymphoglandulae popliteae). 

How many do you find? 

(b) Deep lymphatic vessels (vasa lymphatica profunda). 

Study in the floor of the fossa 

(a) Popliteal surface (planum popliteum) of the femur. 

(b) Posterior ligament (ligamentum popliteum obliquum) of the knee- 

joint. 

(c) Strong fascia covering popliteal muscle. From what muscle is this 

fascia derived? 

A careful drawing of the boundaries and contents of this 
fossa should now be made. Each structure should be shown in 
its proper relation and carefully labelled. To complete the study 
make use of cross-sections. Make a drawing of a section through 
the middle of the space, labelling each structure found and giving 
correct relations. 

POSTERIOR SURFACE OF THIGH (FACIE S FE MORIS 

POSTERIOR). 

Make a vertical incision through the belt of skin remaining 
in the middle of the thigh. Reflect the flaps thus formed lateral- 
ward and medialward respectively. 

Superficial Fascia and Cutaneous Nerves. 

Note carefully branches of arteries and radicles of veins. 
Preserve these as carefully as possible and trace back the larger 
vessels. Study the cutaneous nerves in the superficial fascia. 
Consult Fig. 47, p. 124. 

(a) Branches of the posterior cutaneous nerve of the thigh (N. cutaneus 

femoris posterior) (0. T. small sciatic). 

(b) On the lateral surface of the thigh, passing backward, branches 

the lateral cutaneous nerve of the thigh (N. cutaneus femon* lat- 
eralis) (0. T. external cutaneous). 

(c) On the inner aspect of the thigh, near the knee, the cutaneous branc 

of the obturator nerve (ramus cutaneus nervi obturatoris) ; als 
twigs from the rami cutanei anteriores nervi femoralis. 

Deep Fascia (Fascia lata). (" Broad Fascia.") 

Clean away carefully and completely the superficial fascia 
and expose the deep layer of fascia. Note especially its 



136 LABORATORY MANUAL OF HUMAN ANATOMY 

ness at different levels. The deep fascia may next be removed. 
Follow the rule already given for removal of fascia. Avoid the 
nervus cutaneus femoris posterior in the median line. 

Muscles of Back of Thigh. 

Note carefully the form, position, origin, insertion, action, 
and nerve supply of each of the following : 

(a) Biceps muscle of thigh (M. biceps femoris). 

(aa) Long head (caput longum). 

(ab) Short head (caput breve). 

(b) Semitendinosus muscle (M. semitendinosus) . 

(c) Semimembranosus muscle (M. semimembranosus). 

What do you understand by the hamstring muscles ? 

Nerves of Back of Thigh. 

(a) Posterior cutaneous nerve of thigh (N. cutaneus femoris posterior) 

(0. T. small sciatic). This nerve will be found directly underneath 
the deep fascia in the median line of the thigh. 

(b) Great sciatic nerve (N. ischiadicus] . Note the level at which this 

nerve divides into the N. tibialis and the N. peronaeus communis. 
What are the muscular branches (rami musculares) of the nerve 
and to what muscles are they distributed'? What is the relation of 
the N. peronaeus communis to the biceps muscle? Is there a 
triangle formed by the hamstring muscles in which you can readily 
find the N. ischiadicus? 

Blood-vessels and Lymphatics of Back of Thigh. 

The following arteries and accompanying veins will be seen 
piercing the large muscle inserted into the linea aspera. What 
muscle is this ? 

Arteries. 

(a) First perforating artery (A. perforans prima). 

(b) Second perforating artery (A. perforans secunda). 

(c) Third perforating artery (A. perforans tertia). 

Determine from which of these arteries the superior nutrient 
artery of the femur (A. nutricia femoris superior) and the infe- 
rior nutrient artery of the femur (A. nutricia femoris inferior) 
are derived. Clean each artery and trace it back to the muscle 
which it pierces. Dissect out the fibrous passage-way through 
which each artery passes. Note that these openings are in the 
same line with and exactly analogous to the one through which 
the terminal portion of the deep femoral artery (A. prof undo, 
femoris) passes to the back of the thigh. The terminal part of 
this artery is sometimes called the " fourth perforating artery." 
What is the purpose of these fibrous arches ? 



DISSECTION OF THE LOWER EXTREMITY 



137 



Veins. 

(a) First perforating vein (V. perforans prima). 

(b) Second perforating vein (V. perforans secunda). 

(c) Femoropopliteal vein (V. femoropoplitea). Into what larger vein 

does each empty? 

FIG. 54. 



A. epigastrica superf. .. 
A. cireumflexa ilium superf. - 



A. cireumflexa fern, lat 



Ramus desc. A. circ. fern, lat 




V Aa. pudendae ext. 



-.-.A. cireumflexa med. 



JA. prof, femoris 
. perforans prima 




A. genu sup. lat. 




?-.-.. A. perforans secunda 

3 jJ-A. perforans tertia 
A. genu suprema 



.'. A. genu sup. med. 



Schema of the arteria femoralis. (From Poirier et Charpy Traite d' Anat. hum., 
Paris. 1901. 2 ed.. t. ii. p. 818, Fig. 4/1.) 



Paris, 1901, 2 ed., t. ii. p. 

Determine accurately the course of each of the preceding arteries and 
veins. What is their relation to the M. vastus lateralis 



138 LABORATORY MANUAL OF HUMAN ANATOMY 

Lymphatics. (Fig. 50.) 

Do you find any lymphatic vessels ? If so, determine their course and 
distribution. Are any lymph-nodes (lymphoglandulae} to be found 
in this region? 

Great Adductor Muscle (M. adductor magnus). 

After having completed the dissection of the popliteal sur- 
face, divide the conjoined tendon of the M. semitendinosus and 
M. biceps, exposing the origin of the M. semimembranosus. 
After studying the origin of this muscle and charting the length 
and breadth of its origin, reflect it downward. 

Determine accurately the relation of the M. adductor magnus 
to the linea aspera. What is the adductor tubercle? The form, 
position, origin, insertion, action, and innervation of the great 
adductor muscle can best be studied later. 

Anastomosis upon the Back of the Thigh. (Fig. 54.) 

What vessels enter into the formation of this anastomosis? 
How would the circulation to the leg be carried on if the common 
femoral artery were ligated? Where may the femoral artery 
be ligated most advantageously, and with the greatest possi- 
bility of the establishment of a collateral circulation? 

ANTERIOR SURFACE OF THIGH (FACIES FEMORIS 

ANTERIOR). 

Skin and Superficial Fascia of Upper Part of Anterior Surface of 

Thigh. 
Make the following incisions : 

(a) From the spina anterior superior along the line of the inguinal liga- 

ment of Poupart to the symphysis pubis. 

(b) From the medial extremity of (a) downward, just lateral from the 

scrotum and along the medial surface of the thigh for a distance 
of ten centimetres. 

(c) From the lower extremity of (b) transversely lateralward over the 

anterior surface of the thigh to its lateral aspect. 

Raise the quadrilateral flap thus outlined, taking no fat of the 
superficial fascia with it. 

In the superficial fascia of the lower part of the anterior 
abdominal wall two layers are demonstrable, (1) more super- 
ficial (Camper's fascia), fatty, continuous with the fatty super- 
ficial fascia of the thigh; and (2) a deeper layer (Scarpa's 
fascia), devoid of fat, inserted into the fascia lata a little below 
Poupart 's ligament. Study this fascia in conjunction with the 



DISSECTION OF THE LOWER EXTREMITY 



139 



FIG. 55. 



Lig. inguinale 
[Pouparti] 



Lymphoglamlnlae 
inguiiuiles 



A. i'emoralis 

V. femoralis 

Margo falciform is 

Lymphoglandulae 
subinguinale; 
superticiales 



V. saphena magna _ 




inguinal and adjacent regions. < After TMt, Aimt. Atlas, 
, 1900, 2 Aufl., p. 706, Fig. 1088.) 



140 LABORATORY MANUAL OF HUMAN ANATOMY 

dissector of the abdomen. What bearing have the attachments 
of Scarpa's fascia upon the distribution of extravasated urine? 
Dissect out and study carefully in the superficial fascia the 
following structures : 

Veins. 

(a) Large saphenous vein (V. saphena magna) (0. T. internal saphe- 

nous). 

(aa) Accessory saphenous vein (V. saphena accessoria), incon- 
stant. 

(b) Superficial epigastric vein (V. epigastrica superficialis). 

(c) Superficial circumflex iliac vein (V. circumftexa ilium superficialis}. 

(d) External pudendal veins (Vv. pudendae externae}. 

Arteries. 

(a) Superficial epigastric artery (A. epigastrica superficialis}. 

(b) Superficial circumflex iliac artery (A. circumflexa ilium super- 

ficialis}. 

(c} External pudendal arteries (Aa. pudendae externae) (0. T. super- 
ficial and deep external pudic arteries). 

(d} Inguinal rami of femoral artery (rami inguinales A. femoralis}. 

Lymphatics. (Fig. 55.) 

(a) Inguinal lymph-glands (lymphoglandulae inguinales}. 

Whence do they draw lymph? Whither does the lymph go 
from them? 

(6) Superficial subinguinal lymph-glands (lymphoglandulae subingui- 
nales superftciales) . 

Whence do they draw lymph? Whither does lymph go from 
them? 

Nerves. (See Fig. 56, p. 143.) 

Avoid injury to the N. ilio-inguinalis, N. spermaticus externus, N. 
lumbo-inguinalis, and N. cutaneus femoris lateralis. These nerves are 
to be studied thoroughly a little later, when the rest of the skin on the 
anterior surface of the thigh is removed. 

Oval Fossa of Thigh (Fossa ovalis) (O. T. Saphenous Opening). 

The structures to be studied at and about the oval opening 
include 

(a) Falciform margin (mar go falciformis}. 

(aa) Superior cornu (cornu superius). 

(ab) Inferior cornu (cornu inferius). 

(b) Covering of cribriform fascia (fascia cribrosa). 

(c) Junction of V. saphena magna with V. femoralis. 

(d) Lymph-glands. 

Remove with great care the superficial fascia of the region, 
beginning over the upper part of the M. adductor longus and M. 
pectineus, cleaning the deep fascia (fascia lata) lying beneath. 
Note that the latter is attached above to the posterior margin of 



DISSECTION OF THE LOWER EXTREMITY 141 

Poupart's ligament. Following this portion of the fascia, fascia 
pectinea (0. T. pubic portion of fascia lata), lateralward, it will 
be seen to pass beneath the femoral vessels so as to line the fossa 
iliopectinea, becoming continuous lateralward with the fascia 
iliopectinea. The inferior cornu of the falciform margin is now 
visible. It belongs to that part of the fascia lata which lies 
lateral from the fossa ovalis, viz., the superficial layer of the 
fascia lata (0. T. iliac portion of fascia lata), and is inserted 
medialward into the fascia pectinea or deep layer. Observe the 
cribriform fascia (fascia cribrosa) closing the aperture of the 
fossa ovalis. The superficial subinguinal lymph-glands must be 
removed to display it properly. What vessels pass through this 
fascia cribrosa? 

Remove the fascia cribrosa carefully, so that the edge of the 
margo falciformis and its cornu superius may be clearly defined. 
The upper horn (cornu superius) (0. T. femoral ligament or 
Key's ligament or ligament of Allan Burns) consists of two 
layers, an anterior and a posterior. 

The anterior layer of the cornu superius is a broad lamina, strength- 
ened by Scarpa's fascia; it bounds the fossa ovalis above and lies ver- 
tically between it and Poupart's ligament, to which it is attached. The 
posterior, thicker layer of the cornu superius extends further upward 
than the anterior, passes superficial to the femoral vessels medialward and 
upward, assumes a horizontal position, filling up the acute angle between 
the medial end of Poupart's ligament and the pecten ossis pubis, and 
really forming (by fusion with the process of Poupart's ligament to the 
pecten) the anterior or inferior part of the ligamentum lacunare [Giin- 
bernati]. 

The femoral canal will be studied farther on. Beneath the 
fascia cribrosa within the fossa ovalis observe the deep sub- 
inguinal lymph-glands (lymphoglandulae subinguinales pro- 

fundae). 

Skin and Superficial Fascia of Anterior Surface of Thigh and Knee. 

Continue the vertical incision on the medial aspect of the 
thigh distalward as far as the medial condyle of the tibia. Make 
another incision from the medial condyle of the tibia lateralward 
across the front of the leg as far as the lateral condyle of the 
tibia. Eeflect the large flap lateralward, taking no fat with t 
skin and avoiding injury to nerves and blood-vessels and to tlio 
subcutaneous praepatellar bursa. 

In the fat of the superficial fascia dissect out carefully 1 
following structures: 



142 LABORATORY MANUAL OF HUMAN ANATOMY 

Veins. 

(a) Large saphenous vein (V. saphena magna) (0. T. internal saphe- 
nous vein) and its tributaries. 

Nerves. 

(a) Ilio-inguinal nerve (N . ilio-inguinalis] . 

(b) Lumbo-inguinal branch of genitofemoral nerve (N. lumbo-ingui- 

nalis N. genitofemoralis) (0. T. crural branch of genitocrural ) . 

(c) Lateral cutaneous nerve of thigh (N. cutaneus femoris lateralis) 
(0. T. external cutaneous). 

Follow this nerve into the sheath formed for it by the fascia lata. 
People whose occupations require excessive standing or walking (fascia 
lata tense) sometimes suffer from a severe neuralgia of this nerve, 
so-called " meralgia paraesthetica," or " Bernhardt's disturbance of 
sensibility in the thigh." 

(d) Branches of femoral nerve (N. femoralis) (0. T. anterior crural). 

(da) Anterior cutaneous rami (rami cutanei anteriores) (0. T. 

middle and internal cutaneous). 

(db) Infrapatellar ramus of saphenous nerve (ramus infra- 

patellaris N. sapheni) (0. T. patellar branch of long 
saphenous). Look for it near the cutaneous branch of 
the A. genu suprema. 

(dc) Cutaneous ramus of obturator nerve (ramus cutaneus N. 

obturatorii). 

Bursa. 

Subcutaneous praepatellar bursa (bursa praepatellaris subcutanea). 
Pinch up a bit of tissue in front of the patella with forceps and 
make a transverse cut into the bursa. Explore with the finger. 

Deep Fascia of Thigh (Fascia lata). 

Clean the surface of the fascia lata carefully and examine its 
attachments above and below. Compare with the description in 
your systematic text-book. Pay especial attention to the fol- 
lowing points : 

(a) Superficial layer of fascia lata and margo falciformis of fossa ovalis 

(0. T. iliac portion of fascia lata). 

(b) Deep layer of fascia lata or fascia pectinea (0. T. pubic portion of 

fascia lata). 

(c) Cribriform fascia (fascia cribrosa). This is really a thin continuation 

of (a). 

(d) Iliotibial band (tractus iliotibialis [Maissiati]). What is its sig- 

nificance ? 

(e) White lines corresponding to intermuscular septa in depth. 

(ea) Lateral intermuscular septum of thigh (septum intermus- 
cular e [femoris} laterale) (0. T. external intermuscular 
septum). 

. (eb) Medial intermuscular septum of thigh (septum intermus- 
culare [femoris] mediale) (0. T. internal intermuscular 
septum). 



DISSECTION OF THE LOWER EXTREMITY 



143 



FIG. 56. 



N. cutan. fern. lat. 



Ramus N. cutan. surae l 



N. lumbo-inguiimlis 



iRami cut. ant. 



N. cut. dors. med... 
N. cut. dors, intermed... 

N. cut. dors. lat. 




N. saphenus 



N. peronaeus superf. 



N. per. prof. 



Cutaneous nerves of the flexor side of the lower extremity (schematic). (From Gegenbaur, I.-hrb. 
der Anat. des Mensch., Leipzig, 1899, 7 Aufl., Bd. ii. p. 516, Fig. 669.) 



144 



LABORATORY MANUAL OF HUMAN ANATOMY 



Note that these two septa divide the thigh into two great 
osteofascial compartments, one in front, the other behind. The 
latter is further subdivided by a layer of fascia, sometimes called 
the * ' posterior intermuscular septum. ' ' The further dissection 
will reveal the following contents of these osteofascial compart- 
ments. (Fig. 57.) 



FIG. 57. 

V. femoralis 



jV. saphenus 
M. sartorius 



M. rectus femoris 



A. femoralis 
M. adductor longus 

V. saphena magna 

Sept u m intcrmusculare ~ 
(femoris) mediate 

M.gracilis- 



A. profunda 
femoris 



M. adductor magnus 
M. semimeiribranosus 
M. semitendinosus 




M. rust it s intermedium 
M. rastits mcdialis 



_ M. vast us latcraHs 



Fascia lata ( Tract us 
iliotibialis) 

Septum wtermusculare 

(femoris ) laterale 
. perforans 



isckiadictu 

J/. bleep* fcmor is (caput longum) 



Cross-section of right thigh, a little above its middle. Surface distal to the cut. (After Toldt, 
Anat. Atlas, Wien, 1900, 2 AufL, p. 640, Fig. 1020.) 

(1) In the anterior osteofascial compartment (in front, between the me- 

dial and lateral septa) the extensor muscles and the femoral nerve. 

(2) In the posterior osteofascial compartment (behind, between the medial 

and lateral septa), 

(a) Between the lateral and posterior septa, the flexor muscles and 

the great sciatic nerve. 

(b) Between the medial and posterior septa, the adductor muscles 

and the obturator nerve. 



Sheath for Femoral Vessels and Femoral Canal. 

Before proceeding to this dissection, the student should study 
thoroughly, on a dry preparation of the pelvis with its ligaments, 
the following : 

(a) Inguinal ligament of Poupart (Lig. inguinale [Pouparti]}. 

(b) Lacunar, ligament of Gimbernat (Lig. lacunare [Gimbernati] ). 

After this, divide the cornu superius of the margo falci- 
formis of the fossa ovalis and carry the knife lateralward just 



DISSECTION OF THE LOWER EXTREMITY 145 

below Poupart's ligament to within two or two and a half cen- 
timetres of the spina iliaca anterior superior, so as to sever the 
attachment of this portion of the fascia lata from the ligament. 
Reflect the fascia and margo falciformis downward and lateral- 
ward. Carefully pick out the fat and deep subinguinal lymph- 
glands immediately subjacent, so as to expose the connective 
tissue sheath of the femoral vessels. With the handle of the 
scalpel gently separate the sheath from Poupart's ligament in 
front and from Gimbernat's ligament medialward from it. 

What is the shape of the femoral sheath? Note the points 
where it is perforated by 

(a) Lumbo-inguinal branch of genitofemoral nerve. 

(b) Large saphenous vein. 

(c) Lymp h- vessels. 

By a study of the cadaver, the use of models and a systematic 
text-book of anatomy, ascertain how it is that the anterior wall 
of the femoral sheath represents the continuation into the thigh 
of the fascia transversalis of the abdomen, the posterior wall of 
the sheath the continuation of the fascia iliaca of the abdomen. 

Next open the femoral sheath by making three parallel and 
vertical incisions, the first over the femoral artery, the second 
over the femoral vein, and the third one centimetre medial 
from the second. The incisions all begin above at the Lig. in- 
guinale [Pouparti], the medial one being one centimetre long, 
each of the other two from three to four centimetres long. Note 
the septa, dividing the sheath into three compartments (Fig. 
58)- 

(a) Lateral compartment. 

It contains the A. femoralis and the N. lumbo-inguinalis. 

(b) Middle compartment. 

It contains the V. femoralis. 

(c) Medial compartment (femoral canal or canalis femoralis) (0. T. 

crural canal). 

It contains a lymph-gland ( Rosenmiiller's lymph-gland), some 
lymphatic vessels, and loose areolar tissue. 

Observe that the femoral sheath and its contents completely 
fill up the lacuna vasorum. How is the lacuna vasorum bounded ? 
How is the lacuna musculorum bounded? What structures pass 
through the lacuna musculorum? This latter region will be dis- 
sected later. 

Introduce the little finger into the canalis femoralis. 
long is it ? How is it bounded ? Locate exact position of superior 

10 



146 



LABORATORY MANUAL OF HUMAN ANATOMY 



aperture, the so-called " femoral ring" (annulus femoralis) 
(0. T. crural ring). What is directly medial and what directly 
lateral from this ring? How is it closed above? Can you find 
the femoral septum of CJoquet (septum femorale [Cloqueti] ) ? 

What is meant by femoral hernia? Why should it occur 
where it does and not elsewhere ? Is it more common in males or 
in females, and why? What must have been the course of a 
hernia presenting over the fossa ovalis? In cutting down upon 



M. obliquus interims 



FIG. 58. 

Spina iliaca anterior superior 

Aponeurosis of the M. obliquus externus abdominis 
k Fascia transversalis 
Hj^ Nervus femoralis 

Fascia iliopectinea 

Lig. inguinale [Pouparti\ 
\^ Arteria femoralis 
\ ^v- X Vagina vasorum 




Vena femoralis 



Annulus femoralis 

Lig. lacunare 
[Gimbernati] 



M. rectus ab- 
dominis 




Cut edge of th( 
fascia iliaca 



M. iliopsoas Eminentia iliopectinea \ Fades symphyseos 

Fascia transversalis i Falx (aponeurotica) 

Lig. pubicum [Cooperfj \ inguinalis 

Annulus inguinalis subcutaneus 

The lacuna musculorum and the lacuna vasorum of the left side, seen from the internal, 
medial side. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 374, Fig. 616.) 

it, what are the various coverings met with? Where is such a 
hernial sac most subject to constriction? How could such con- 
striction be relieved by the knife? In cutting Grimbernat's liga- 
ment, what is to be remembered about the origin of the obturator 
artery ? 

Femoral Triangle, or Larger Fossa of Scarpa (Trigonum femorale 

[Fossa Scarpae major]) (O. T. Scarpa's Triangle). 
Remove the fascia lata from the anterior aspect of the proxi- 
mal third of the thigh. Do not disturb the fascia lata farther 



DISSECTION OF THE LOWER EXTREMITY 
FIG. 59. 



147 






A. epigastrica - 

superficialis 
M. tensor fasciae latac- 

N. femoralis - 
A. femoralis -- 



V. femoralis--- 

M. sartorius-- 

A. profunda femoris--- 

A.circumflexa| Ram - ascendens -' 
femoris laterahs| Ram de scendens - 

Cut edge of the lamina superficialis - 
fasciae latae 

A. perforans prima 
A. profunda femoris -- 

M. vastus medialis 



V. femoralis 
N. saphenus 
A. femoralis 

M. rectus femoris --- 



Rete articulare genu 




A. spermatica externa 



A. circumflexa femoris 
medialis 



Ramus superficialis 



M. adductor brevis 



M. adductor longus 



M. gracilis 



^Anterior wall of the canalis 
adductorius [Hunteri] 



-Ramus muscularis 

- N. saphenue 
M. sartor i a .< 
A. genu suprema 



--.A. genu superior medialis 
-.Ramus articularis 

^Ramus saphenus 



The femoral arterv to its entrance into Hunter's canal, and 
segment of the M. sariorius has been taken away. (After Toldt, Anat. Atlas, * 
Fig. 1003. ) 



148 LABORATORY MANUAL OF HUMAN ANATOMY 

distalward. The boundaries of the triangle may now be defined 
and its contents dissected out. Remove the femoral sheath and 
clean the vessels, nerves, and muscles related to the triangle. 

How is the femoral triangle bounded above, lateralward, and 
medialward? How is its floor formed? 

Among the contents find and study the following, comparing 
your findings with the descriptions in a systematic text-book. 

Arteries. (Fig. 59.) 

(a) Femoral artery (A. femoralis). Study carefully the relations of 
this artery in different parts of Scarpa's triangle. 

(aa) Superficial epigastric artery (A. epigastrica superficialis}. 

(ab) Superficial circumflex iliac artery (A. circumflexa ilium 

superficialis). 

(ac) External pudendal arteries (Aa. pudendae externae) (0. T. 

superficial and deep external pudic arteries). 

(ad) Inguinal rami (rami inguinales). 

(ae) Muscular rami (rami musculares) . 

(af) Deep artery of thigh (A. profunda femoris). 

(a fa) Medial circumflex artery of thigh (A. circumflexa 

femoris medialis) (0. T. internal circumflex). 

(afb) Lateral circumflex artery of thigh (A. circumflexa 

femoris lateralis) (0. T. external circumflex). 

(afc) Superficial ramus (ramus superficialis). 

Veins. 

(a) Femoral vein (V. femoralis). 

(aa) Superficial epigastric vein (V. epigastrica superficialis). 

(ab) Superficial circumflex iliac vein (V. circumflexa ilium 

superficialis). 

(ac) Thoraco-epigastric vein (V. thoraco-epigastrica) . 

(ad) External pudendal veins (Vv. pudendae externae) (0. T. 

external pudic veins). 

(ae) Large saphenous vein (V. saphena magna) (0. T. internal 

saphenous). 

(af) Deep vein of thigh (V. profunda femoris). 

(afa) Medial circumflex veins of thigh (Vv. circumflexae 

femoris mediates) . 

(afb) Lateral circumflex veins of thigh (Vv. circum- 

flexae femoris later ales}. 

Nerves. 

(a) Lumbo-inguinal nerve (N. lumbo-inguinalis) (0. T. crural branch 

of genitocrural). 

(b) Lateral cutaneous nerve of thigh (N. cutaneus femoris lateralis) 

(0. T. external cutaneous). 
How much of this nerve is in the triangle? 

(c) Femoral nerve (N. femoralis) (0. T. anterior crural). 

What is the relation of the branches of this nerve, given off in 
this fossa, to the A. circumflexa femoris lateralis 1 ? 



DISSECTION OF THE LOWER EXTREMITY 



149 



Sartorius Muscle and Hunter's Adductor Canal (M. sartorius et 
Canalis adductorius [Hunteri]). (Figs. 59 and 60.) 

Eemove the fascia lata from the distal two-thirds of the thigh, 
leaving, however, the iliotibial band on the lateral surface. Clean 
the M. sartorius carefully, watching for the nerves which are 
near it or pass through it. Study its form, position, origin, in- 
sertion, action, and innervation. Whence has it received its 
name ? 

What is meant by " Hunter's canal' ' or the " adductor 
canal" (canalis adductorius [Hunteri]) ! Note that it is the 
continuation distalward of the lacuna vasorum. How is the 



V. femoralis 
A. femoralis I 



FIG. 60. 

M. vastus medialis 



N. saphenus 

Aponeurotic union between the 
M. vast us medialis and the 
J(. adductor magnus (ante- 
rior u-all of the canalis ad- 
ductorius) 

M. sartorin 



Canalis adductorius _. 

[Hunteri] 
V. saphena magna - 

M. adductor magnus, 
M. gracilis-' 

A. perforans III.--- 



M. semimembranomS'' 




-~M. rectus femoris 

M. vastus intermedium 
..Fascia lata 

M. vastus lateralis 



Septum internutfculare 

(femoris) laterale 
'. biceps femoris 
'<i ]>ut breve) 
x. ttduadtau 



M. biceps femori* 
(caput longum) 
M. semitendinosus 



Cross-section of the right thigh through Hunter's canal, a little above the opening in the adductor 
magnus muscle. Surface distal to the section. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 641, 

Fig. 1021.) 

canal or tunnel formed? Study the constituents of the walls of 
the canal. Cut through the fibrous expansion forming the ante- 
rior wall of the adductor canal and study the contents of the 
canal. How do the femoral vessels leave the canal to enter the 
popliteal space? Describe the opening in the M. adductor mag- 
nus (hiatus tendineus adductorius). At what point do the N. 
saphenus and the A. genu suprema leave the canal? Study 1 
lower part of the A. femoralis and its relations. Examine the 
following branches: 

(a) Muscular rami (rami musculares). What muscles are supplied by 
these? 



150 LABORATORY MANUAL OF HUMAN ANATOMY 

(b) Highest artery of knee (A. genu supremo] (0. T. anastomotica 
magna). 

(ba) Saphenous ramus (ramus saphenus). 

(bb) Muscular ramus (ramus muscularis). 
(be} Articular rami (rami articular e s) . 

Review now the femoral vein throughout its whole course, 
examining its various tributaries. How does its relative position 
as regards the femoral artery change as it proceeds distalward 
towards the hiatus tendineus adductorius? With scissors slit 
the vein open along its whole length and look for valves. The 
femoral vein is often thrombosed in the course of typhoid fever, 
or in pelvic infections, especially during the puerperal period 
(phlegmasia alba dolens). 

Femoral Nerve and Muscles of Front of Thigh. (Fig. 61.) 

Clean the muscles of the front of the thigh carefully and 

follow the nerve branch to each. 

Study thoroughly the femoral nerve (N. femoralis) (0. T. 

anterior crural) and all its branches, cutaneous and muscular. 

What are these and what do they supply? Does the femoral 

nerve innervate joints! 

Study the form, position, origin, insertion, action, and inner- 

vation of each of the following muscles : 

(a) Tensor muscle of fascia lata (M. tensor fasciae latae) (0. T. tensor 

vaginae femoris). Study exact relation to 
(aa) Iliotibial band (tractus iliotibialis [Maissiati]) . 

Cut through the iliotibial band below the tensor muscle, 
deflect it forcibly lateralward, and displace the M. vastus 
lateralis medialward so as to expose the lateral intermuscu- 
lar septum (septum inter muscular e [femoris'] laterale). 
How is it attached at its two edges'? What important 
structures perforate it? 

Examine also the medial intermuscular septum (septum 
inter muscular e [femoris] mediale). Which is the stronger, 
the medial or the lateral septum? 

(b) Quadriceps ("four-headed") muscle of thigh (M. quadriceps femo- 

ris). 

(ba) Rectus ("straight") muscle of thigh (M. rectus femoris}. 

(baa) Bursa M. recti femoris. 

(bb) Vastus lateralis muscle ("lateral great muscle") (M. vastus 

lateralis) (0. T. vastus externus). 
(be) Vastus medialis muscle ("medial great muscle") (M. vastus 

medialis) (0. T. vastus internus). 
(bd) Vastus intermedius muscle ("intermediate great muscle") 

(M. vastus intermedius) (0. T. crureus). 

Cut through the M. rectus femoris at its middle and 

reflect distal end forcibly. Find the groove between the M. 



DISSECTION OF THE LOWER EXTREMITY 



L51 



FIG. 61. 



M. psoas major. 

M. iliacm 
N. femoralis 

Lig. inguinalc [Pouparti], 

M. s 

Superficial branches of the 
X. femoralis (cut off) 

M. ten xor fasciae latae 
Rami musculares 



M. ri'ct us femoris- _ 
(tamed aside) i 



Ramus articularis 

Ramus muscularis for the - 
M. vast us medialis 



M. vastus lateralis 
M. vastus intcrmedius - 



N. saphenus- 



Ramus muscularis for the 

M. vastus lateralis and 

for the knee-joint 

M. vastus medialis 



M. rectus femoris _ 




A. et V. iliaca ejcterna 
N. obturatorius 

Proiiinntnriiiin 

M. i>ictineu8 

Li' i. juibocapsulare 

Opening nf th< caimli* 

oomraforfiM 

M. obturator extcrnus 

Ramus ante- 



Fascia lata 



Patilla 



Rami musculares 



M. adductor longus 
(turned aside) 



*vRami musculares from 
the ramus i>osterior 

M. adductor />/>;/> 



M. ffracilis 



-- Ramus cutaneus of the 

N'. obturatorius 
M. adductor mn<j i< a* 

M. inlilnctor Inniins 
A. and V.femontli* 
Entrnnci to tlir nninlia nd<lurt,triu* 



Ramus cutaneus of the N. fern. 
which joins the ramus cutaneus 
of the N. obturatorius 



-. N. saphenus 



LH M. 



The branching of the femoral and obturator nerv s.vn fnnn in fn.n, af,,r par.i.l n,nov,,l ,,( 
the Mm. sartorius, rectus iemoris, adductor longus. an-l peetinena. (AftH Wdt, Anat. Atla>. \\ 
1903, 3 Aufl., p. 839, Fig. 1275. ) 



152 LABORATORY MANUAL OF HUMAN ANATOMY 

vastus medialis and the M. vastus intermedius and follow 
it proximalward. Observe the nerve to the M. articularis 
genu running along the medial margin of the M. vastus 
intermedius. Cut through the body of the M. vastus me- 
dialis transversely five centimetres above the patella and 
reflect it mediahvard. Examine carefully the origin of the 
M. vastus medialis. 

(be) Articular muscle of knee (M. articularis genu) (0. T. sub- 
crureus). 

Make a vertical incision through the M. vastus intermedius 
so as to expose the M. articularis genu. What is the relation of 
the tendon of insertion of the latter muscle to the capsule of the 
knee-joint? 

Study the relations of the various constituents of the M. 
quadriceps femoris to the patella and the ligamentum patellae. 
Examine the retinacula patellae mediale et later ale. When the 
patellar tendon is struck during life, what constituents of the 
M. quadriceps femoris contract most? Try it on yourself at 
home with the thigh exposed. 



MEDIAL SURFACE OF THIGH (FACIE 8 MEDIALIS 

FEMORIS}. 

Long Adductor Muscle (M. adductor longus). 

Study its form, position, origin, insertion, action, and inner- 
vation. Then divide it near its origin and reflect it lateralward. 
Avoid injury to the ramus anterior of the N. obturatorius. 

Deep Artery of Thigh (A. profunda femoris) and M. Pectineus. 

The beginning of this artery and some of its branches have 
already been studied in the femoral triangle of Scarpa. Sepa- 
rate the aponeurotic tendon of the M. adductor longus from the 
M. vastus medialis in front and the M. adductor magnus behind, 
and study the deeper portions of the deep artery and vein of the 
thigh (A. and V. profunda femoris). The perforating branches 
of the artery deserve especial attention (cf. Fig. 54, p. 137) : 

(a) First perforating artery (A. perforans prima). 

(aa) Superior nutrient artery of femur (A. nutricia femoris 
superior). 

(b) Second perforating artery (A. perforans secunda). 

(c) Third perforating artery (A. perforans tertia). 

(ca) Inferior nutrient artery of femur (A. nutricia femoris infe- 
rior). 



DISSECTION OF THE LOWER EXTREMITY 153 

The pectineus muscle (M. pectineus) should now be carefully 
studied. Ascertain its exact form, position, origin, insertion, 
action, and innervation. Note that it is covered by the fascia 
pectinea (0. T. pubic portion of fascia lata). Observe the bursa 
M. pectinei. 

Short Adductor Muscle (M. adductor brevis), Medial Circumflex 
Artery, and Obturator Nerve. 

Cut through the M. pectineus at its origin and reflect it distal- 
ward and lateralward. Avoid injury to the ramus anterior of 
the N. obturatorius. Is an accessory obturator nerve present? 
Dissect out the branches of the medial circumflex artery (A. cir- 
cumflexa femoris medialis) in this region and review the artery 
as a whole. Follow especially 

(a) Superficial ramus (ramus super ficialis). 

(b) Deep ramus (ramus profundus). 

(c) Acetabular ramus (ramus acetabuli). 

Clean the short adductor muscle (M. adductor brevis) and 
study its form, position, origin, insertion, action, and innerva- 
tion. Then cut through it at its origin and reflect it distalward 
and lateralward. Now dissect out the posterior ramus of the ob- 
turator nerve (N. obturatorius) and study the nerve as a whole. 
How does it get into the thigh? What muscles receive their 
motor innervation from it? How do the anterior and posterior 
rami differ in their relations ? Which sends a branch to the hip- 
joint? Which to the knee-joint? How is the obturator innerva- 
tion of the hip and knee of interest in hip-joint disease? 

Other Muscles on Medial Side of Thigh. 

Study the form, position, origin, insertion, action, and inner- 
vation of the following: 

(a) Gracilis ("slender") muscle (M. gracilis). 

(aa) Bursa M. sartorii propria. 

(ab) Bursa anserina. 

(b) Smallest adductor muscle (M. adductor minimus) (0. T. upper por- 

tion of adductor magnus). 

(c) Great adductor muscle (M. adductor magnus). 

(ca) Hiatus tendineus adductorius (already studied). 

Observe its double nerve-supply. 
Detach (b) and (c) at their origins and reflect them. 

(d) External obturator muscle (M. obturator externus). 

(e) Psoas major ("larger lumbar") muscle (M. psoas major). 

(f) Iliac muscle (M. iliacus). 

The conjoined tendon of (e) and (/) may now be studied. 



154 



LABORATORY MANUAL OF HUMAN ANATOMY 



Obturator Artery (A. obturatoria). (Cf. Spalteholz, Fig. 469.) 

Eeflect the M. obturator externus and in it and beneath it find 
the following branches of the obturator artery : 

(a) Anterior ramus (ramus anterior). 

(b) Posterior ramus (ramus posterior). 

(ba) Artery of acetabulum (A. acetabuli). 



HIP- JOINT (ARTICULATIO COXAE}. 

Cut through the A. femoralis, V. femoralis, and N. femoralis 
two or three centimetres below Poupart's ligament; tie the dis- 



FIG. 62. 



Lig. iliofemorale 
(fasc. ilio-pretrochanter.) 




Memb. obturat. 



Articulatio coxae, anterior view. (From Poirier et Charpy, Traits 
d'Anat. hum., Paris, 1899, 2 ed., t. i. p. 716, Fig. 721.) 

tal stumps together and reflect them distalward. Then cut 
through the M. sartorius and M. rectus femoris five centimetres 
from their origin and reflect them. Cut away the conjoined 
tendon of the M. iliacus and M. psoas at its insertion and turn 
it proximalward. Examine the bursa iliopectinea, the bursa M. 



DISSECTION OF THE LOWER EXTREMITY 



155 



recti femoris, and the bursa iliaca subtendinea. Reflect the M. 
tensor fasciae latae. Clean the outer surface of the hip-joint. 

The joint is an enarthrosis. What is meant by this? What 
bony surfaces are concerned! 

Study the following ligaments (Figs. 62 and 63) : 

(a) Joint-capsule (capsula articularis). 

(b) Strengthening ligaments. 

(ba) Iliofemoral ligament (ligamentum iliofemorale) (0. T. Y- 

shaped ligament of Bigelow ) . 

(baa) Superior fasciculus to tubercle in front of great 
trochanter (Lig. iliofemorale superius). 



FIG. 63. 



M. glut, min 



Caps, articularis _ 




.M. obt. ext. 



Frontal section of the articulatio coxae, passing through the fovea capitis femoris (From 
Poirier et Charpy, Traite d'Anat. hum., Paris, 1899, 2 ed., t. i. p. 7-M, 1' ' 

(bab) Anterior or inferior fasciculus to tubercle in front 
of small trochanter (/.///. iliofemorale ///// rin). 

This is perhaps the strongest ligament in tho 
body. It will resist a strain of from two hundred 
and fifty to seven hundred and fifty pounds. 
(bb) Ischiocapsular ligament (ligamentum ischiocapsular^ 

ischiocapsular band). 
(be) Pubocapsular ligament (ligamentum j.ul.n.apsulan 

pubocapsular band or pubofemoral l.uamrnt ) 
(bd) Orbicular zone (zona orhn-nlans) ,O. T. xonular 1 
ring ligament). 



156 LABORATORY MANUAL OF HUMAN ANATOMY 

Make the maximal movements in the joint in the direction of 
(1) extension, (2) flexion, (3) adduction, (4) abduction, (5) rota- 
tion medialward, (6) rotation lateralward, (7) circumduction. 
How are the ligaments affected in each instance ? What muscles 
are concerned in each movement in the living body ? 

Open the articulation. Eemove the whole capsule first, with 
the exception of the ligamentum iliof emorale. Test the strength 
of this and then remove it. 

Study each of the following ligaments : 

(a) Glenoid lip (labrum glenoidale] (0. T. cotyloid ligament). 

(b) Transverse ligament of acetabulum (ligamentum transversum ace- 

tabuli) . 

(c) Round ligament of the femur (ligamentum teres femoris). 

This would be better designated " triangular ligament," or, better 
still, Lig. intrarticulare coxae, a name suggested by Fick. It is 
probable that it is a vestige of a pubofemoral muscle the tendon 
of which has become invaginated into the joint. 

Study the blood supply and nerve supply of the joint. (Cf. 
Poirier et Charpy, t. i., Figs. 731 and 732.) Follow the reflec- 
tions of the synovial membrane. 

Cut through the ligamentum teres, remove the lower extrem- 
ity from the trunk, and continue the dissection at a side-table. 

LEG AND FOOT. 

Make the following incisions: (1) an incision distalward 
along the middle line of the leg and dorsum of the foot, in front, 
extending as far as the base of the middle toe; (2) transverse 
incisions extending (a) across the ankle and (b) across the bases 
of the toes. Reflect the flaps thus formed, taking no fat with the 
skin. 

Superficial Fascia. 

Note the characteristics of this fascia and determine with 
what fasciae it is continuous above and below. Dissect out the 
following : 

Veins. (Vide Spalteholz, Figs. 507-509.) 

(a) Dorsal digital veins of foot (Vv. digitales dor sales pedis}. 

(b) Intercapitular veins (Vv. int er capitular e s] . 

(c) Common digital veins of foot (Vv. digitales communes pedis). 

(d) Dorsal venous arch of foot (arcus venosus dorsalis pedis (cuta- 

neus)). 

(e) Dorsal cutaneous venous network of foot (rete venosum dorsale 

pedis cutaneum). 



DISSECTION OF THE LOWER EXTREMITY 157 

(/) Lateral marginal vein (V. marginalis lateralis). 
(g) Medial marginal vein (V. marginalis medialis). 

Trace these veins proximalward and determine their relation to the 
large saphenous vein (V. saphena magna) and the small saphenous vein 
(V. saphena parva). 

Nerves. (See Fig. 56, p. 143.) 

Refer frequently to charts in the study of cutaneous nerves and 
determine the exact area of skin supplied by each. 

(a) Saphenous nerve (N. saphenus). 

(aa) Medial cutaneous branches of leg (rami cutanei cruris 
medialis). 

(b) Branches of lateral cutaneous nerve of calf (N. cutaneus surae). 

(c) Superficial peroneal nerve (N. peronaeus superficialis) . 

(d) Terminal twigs of deep peroneal nerve (N. peronaeus profundus). 

(e) Dorsal digital nerves (Nn. digitales dor sales}. 

(/) Lateral dorsal cutaneous nerve (N. cutaneus dorsalis lateralis), 
from the N. tibialis. 

Carefully remove the superficial fascia, preserving the struct- 
ures which you have dissected, and expose the deep fascia. 

Deep Fascia of the Leg (Fascia cruris). (Figs. 64 and 67.) 

Observe that this fascia is continuous with the fascia lata; 
note also its shiny, aponeurotic character just below the knee, 
where it gives origin to muscles. Trace the fascia downward, 
noting that it tends to become thinner distalward, but is strength- 
ened just above the ankle to form the transverse ligament of the 
leg (lig amentum transversum cruris) (0. T. upper or broad part 
of anterior annular ligament). Note the exact points of attach- 
ment of the ligament and observe that it sends a septum to the 
tibia, thus forming two compartments, one medial for the M. 
tibialis anterior, one lateral for the M. extensor longus hallucis 
and M. extensor longus digitorum. The fascia cruris becomes 
continuous below with the dorsal fascia of the foot (faxrin 
dorsalis pedis), the latter being continuous at the sides of the 
foot with the plantar aponeurosis (aponeurosis plantar is). In 
the fascia dorsalis pedis examine the Lig. cruciatum cruris (0. 
T. lower part of anterior annular ligament). Determine the 
exact attachments of the two limbs of the Y of this ligament, 
and their relations to the tendons of the muscles over which they 
pass. A good description is given in Spalteholz's Atlas, p. 356. 
Observe the band passing from the lateral malleolus to the pofl 
terior prominence of the os calcis; this is the retinaculun Mm. 
peronaeorum superius (0. T. external annular ligament). 
(Fig. 67.) 



158 



LABORATORY MANUAL OF HUMAN ANATOMY 



Incise now the deep fascia longitudinally, midway between 
the tibia and fibula, but do not cut through the Lig. transversum 
cruris or the Lig. cruciatum cruris. Note that the fascia becomes 
continuous medialward with the periosteum of the tibia, and that 
lateralward it sends a septum into the crista anterior of the 
fibula, forming the anterior [fibular] intermuscular septum (sep- 
tum intermusculare anterius [fibulare]) (0. T. anterior peroneal 
septum). This latter septum separates the contents of the 
" anterior tibiofibular compartment" of the leg from the con- 
tents of the " peroneal compartment." The latter is bounded 
posteriorly by another septum going into the crista lateralis of 



FIG. 64. 

M. tibialis anterior 
Tibia- 



V. saphena magna 
N. saphenus^ 

M. flexor digitorum longus^ 
M. tibialis posterior, 

A. tibialis posterior. 
N. tibialis- 

M. gastrocnemius 
(caput mediate) 

Tendon of the M. plantaris -- 

M. soleus-" 

A", cutaneus surae medialis' 




Membrana interossea cruris 
A. tibialis anterior 

A", peronaeus profundus 

.!/. tjirnsor digitorum longus 
Septum intermuscular e 

anterius (fibulare) 
^ M. extensor hallucis longus 

_N. peronaeus superficialis 
^.M. peronaeus longus 

-.Septum intermusculare 
posterius (fibulare) 

^-A. peronaea 

Lamina pr funda^ fasc . ae 

,. f cruris 
Lamina superficiahs) 

' Ramus anastomoticus peronaeus 
saphena parva 



Cross-section of the right leg a little above its middle. Surface distal to the cut. (After Toldt, 
Anat. Atlas, Wien, 1900, 2 Aufl., p. 642, Fig. 1023.) 

the fibula and known as the posterior intermuscular septum (sep- 
tum intermusculare posterius) (0. T. posterior peroneal sep- 
tum). It will be studied later. Examine Fig. 64 carefully. 



Muscles of Anterior Tibiofibular Region. 

Use cross-sections to complete this study. Study the contents 
of the anterior tibiofibular osteofascial compartment. Clean 
carefully each muscle and determine its form, position, origin, 
insertion, action, and nerve supply. What are flexion and exten- 
sion of the foot? Study 

(a) Anterior tibial muscle (M. tibialis anterior) (0. T. tibialis anticus). 

(b) Long extensor of digits (M. extensor digitorum longus). 



DISSECTION OF THE LOWER EXTREMITY 
FIG. 65. 



A. genu sup. lat. 



Patella 



A. genu infer, lat. 



.A. recurrens tihialisant. 



A. tibialis ant. 



159 





Lig. trans, eruris 

A. malleolaris ant. lat. 

A. dorsalis pedis 
A. arena ta 



Aa. inrtat.-irseae dorsales 



Arteries of the anterior part of the leg. The Mm. ext. hnllm-is long, and ext. dig. long, an- drawn 
aside and the M. ext. dig. hn-vis N divided. (From Gegenbaur, Lehrb. der Anat. dcs Mm-ch.. I 
1899, 7 Aufl., Bd. ii. p. 294, Fig. .547.) 



160 LABORATORY MANUAL OF HUMAN ANATOMY 

(c) Long extensor of great toe (M. extensor hallucis longus). 

(d) Third peroneal muscle (M. peronaeus tertius). 

Examine the vagina tendinis M. tibialis anterioris, the vagina 
tendinis M. extensoris hallucis longi, and the vagina tendinum M. 
extensoris digitorum longi. 

Arteries of Anterior Tibiofibular Region and Dorsum of Foot. 

Separate the M. extensor digitorum longus from the M. tibi- 
alis anterior and expose the following; at the same time dissect 
out the structures on the dorsum of the foot. 

(a) Anterior tibial artery (A. tibialis anterior). (Vide Fig. 65, and 

Spalteholz, Fig. 479.) How does this artery pass to the 
anterior compartment of the leg, and what is its relation 
to the membrana interossea cruris? 

(aa) Posterior recurrent tibial artery (A. recurrens tibialis pos- 

terior). 

(ab) Anterior recurrent tibial artery (A recurrens tibialis an- 

terior). 

(ac) Lateral anterior malleolar artery ( A. malleolaris anterior lat- 

eralis) (0. T. external malleolar). 

(ad) Medial anterior malleolar artery (A. malleolaris anterior 

medialis) (0. T. internal malleolar). 

(ae) Medial malleolar network (rete malleolar e mediale). 

(af) Lateral malleolar network (rete malleolar e laterale). 

The continuation of the anterior tibial artery from in front of the 
ankle-joint is known as the 

(b) Dorsal artery of the foot (A. dorsalis pedis). 

(ba) Lateral tarsal artery (A. tarsea lateralis). 

(bb) Medial tarsal arteries (Aa. tarseae mediales). 
(be) Arcuate artery (A. arcuata). 

(bd) Dorsal network of foot (rete dorsale pedis). 

(be) Dorsal metatarsal arteries (Aa. metatarseae dorsales). 

(bf) Deep plantar branch (R. plantaris profundus). 

Nerves of Anterior Region of Leg and Dorsum of Foot. 

(a) Deep peroneal nerve (N. peronaeus profundus) (0. T. anterior 

tibial). 

(aa) Muscular branches (rami muscular es] . 

(ab) Dorsal digital nerves to lateral surface of hallux and to 

medial surface of digit II. (Nn. digitales dorsales hallucis 

lateralis et digiti secundi medialis). 

Determine how the deep peroneal reaches the anterior surface of the 
leg. Does it accompany the artery? What area of the skin does it 
supply? What muscles are supplied by this nerve? 

(b) Superficial peroneal nerve (N. peronaeus superficialis) (0. T. mus- 

culocutaneous). 

(ba) Muscular branches (rami muscular es). 

(bb) Medial dorsal cutaneous nerve (N. cutaneus dorsalis me- 

dialis). 



DISSECTION OF THE LOWER EXTREMITY 



161 



(be) Intermediate dorsal cutaneous nerve (N. cutaneus dorsali* 

intermedius). 
(bd) Dorsal digital nerves of the foot (Nn. digitales dorsales 

pedis ) . 

The proximal part of the N. peronaeus superficial will 

be studied later. 

FIG. 66. 



N. peronaeus com.. 



V 



\ 



N. et M. peronaea long. M-, 



..N. peronaeus prof. 



M. tibialis ant. 



N. peronaeus superf. 



M. ext. dig. long. . .. 



.._ M. ext. hallucis long. 



N. suralis.,... 



M. peronaeus prof. 



Nn peronaei superficialis et prof undus (after Hirschfeld). (From Poirier et Charpy, 
Traite d'Anat. hum., Paris, 1899, t. iii. p. 1125, Fig. 584.) 



Muscles of Dorsum of Foot. 

Dissect these out carefully, studying the form posit ion, 
origin, insertion, action, and innervation of each. 
67 and Spalteholz, Fig. 402.) 



162 



LABORATORY MANUAL OF HUMAN ANATOMY 



FIG. 67. 



M. peronaeus tertius 



Vagina tendinum , 
Mm. peronaeorum 
commums 



Rctinaculum Mm. 

peronaeorum 

superius 



Retinaculum- 
Mm. peronae- 
orum inferius 



M. extensor 
digitorum brevis 



M. abductor digit! quinti 




Vagina tendinis M. tibialis antmoris 



Vagina tendinum M. extensor-is 
digitorum pedis longi 



Vagina tendinis M. extensor is 
hallucis longi 



_ M. extensor hallucis brevis 



M. opponens digiti quinti 




The muscles on the dorsum and lateral side of the foot. The sheaths of the tendons on the dorsum 
pedis and in the lateral retromalleolar region have been injected with strong alcohol. (After Toldt, 
Anat. Atlas, Wien, 1900, 2 Aufl., p. 356, Fig. 597.) 



DISSECTION OF THE LOWKK KXTKKM1TY 163 

(a) Short extensor of great toe (M. extensor hallucis brevis). 

(b) Short extensor of digits (M. extensor digitorum brevis). 

Determine the relation of these muscles to the tendons of the 
long extensor of the digits. What is their action? Have they 
homologues in the hand? 

(c) Dorsal interosseous muscles (Mm. inter ossei dor sales). 

Compare these with similar muscles found in the hand, as 
regards origin, insertion, action, etc. 

Where are the bursae intermetatarsophalangeae situated? 

LATERAL OR PERONEAL REGION OF LEG (RE GIG 
CRURIS LATERALI8). 

The superficial fascia of this region has already been studied. 
An anterior intermuscular septum (septum inter muscular e ante- 
rius [fibulare] ) has been found passing from the deep fascia into 
the crista anterior fibulae. Incise the deep fascia longitudinally 
in this region ; reflect it posteriorly and note the corresponding 
posterior [fibular] intermuscular septum (septum intermuscu- 
lar e posterius [fibulare] ) going to the crista lateralis fibulae. A 
lateral or peroneal osteofascial compartment is thus formed. 
Dissect its contents and supplement the dissection by the use of 
cross-sections made at different levels ; note carefully the altera- 
tions in the relations of the different contents of the compart- 
ment at different levels. Study the following : 

Peroneal Muscles and Retinacula. 

Clean each muscle carefully, defining well its borders and 
noting the form, position, origin, insertion, action, and innerva- 
tion of each. 

(a) Long peroneal muscle (M. peronaeus longus). What action does this 

muscle have as regards the arch of the foot? 

(b) Short peroneal muscle (M. peronaeus brevis). 

Trace the tendons of both muscles distalward into the foot. 
What are their relative positions in the fossa retromalleolaris 
lateralis? (Cf. Fig. 68.) What is the trochlear process (j,n- 
cessus trochlearis) of the os calcis? Examine the bony foot and 
determine the position of the peroneal sulcus (sulcti* M. peronai '> 
[longi]). 

Define next the retaining bands of the peroneal muscles 
macula}. (Cf. Spalteholz's Atlas, Fig. 409.) 



164 



LABORATORY MANUAL OF HUMAN ANATOMY 



(a) Eetinaculum Mm. peronaeorum superius (0. T. external annular 

ligament). 

(b) Eetina^ulum Mm. peronaeorum inferius. 

What is the relation of the latter to the ligamentum cruciatum 
cruris? (See Fig. 67.) 

Dissect out carefully the common synovial sheath of the pero- 
neal muscles (vagina tendinum Mm. peronaeorum communis). 

FIG. 68. 

M. tibialis ant. A. et V. tibial. ant. and N. peronaeus prof. 
M. ext. hal. long. 



N. saphenus et 
V. saphena 



M. tibial. post- 



M. flex. dig. long. 



A. tibial. post.' 
N. tiabialis/. 



M. plantar 



^ M. ext. dig. long. 




//// " - M. peronaeus long. 



v M. peronaeus brev. 
V. saphena parva 



M. flex. hal. long. ( 
M. triceps surae 



N. suralis 



Cross-section passing through the inferior part of the leg. Right side, segment distal to the line of 

section. 

Anterolateral region (lighter shade). The two groups, anterior and lateral, are plainly separated. 
The M. tiabialis ant. has become tendinous and accompanies the A. tibialis ant. The fleshy fibres of 
the M. peronaeus long, have disappeared. The M. peronaeus brev. is attached to the corresponding 
surface of the fibula. The N. peronaeus superf. has emerged from between the two muscles, but runs 
beneath the fascia cruris, which it is about to perforate. 

Posterior region (darker shade). There is to be noted a displacement of the muscles. The M. 
tibialis post, has left the space between the flexors and, gaining the medial aspect of the leg, passes 
beneath the tendon of the M. flex. dig. long. 

Superficial layer (intermediate shade). The tendo calcaneus [Achillis] receives the lowest fibres of 
the M. soleus. (From Poirier et Charpy, Traite d'Anat. hum., Paris, 1899, 2 ed., t. ii. p. 268, Fig. 196.) 

What is its extent proximalward and distalward? This 
sheath may be seen to better advantage if injected. Note here 
also the subcutaneous bursa over the lateral malleolus (bursa 
subcutanea malleoli later alis). 



Peroneal Nerves. 

Trace the course of the N. peronaeus communis and dissect 
out all the branches : 



DISSECTION OF THE LOWER EXTREMITY 165 

(a) Common peroneal nerve (N. peronaeus communis) (0. T. external 
popliteal nerve). 

(oa) Superficial peroneal nerve (N. peronaeus superficialis) (0. 
T. musculocutaneous nerve). 

(ab) Deep peroneal nerve (N. peronaeus profundus) (0. T. ante- 
rior tibial nerve). 

What muscles are supplied by the superficial peroneal nerve? 
What cutaneous area? Review at this stage of the dissection the 
distribution of the deep peroneal nerve. What are the homo- 
logues of these nerves in the forearm? 

MEDIAL REGION OF LEG (REGIO CRURIS ME- 
DIALIS) (0. T. TIBIAL REGION). 

The student has but little to examine here, as the tibia is sub- 
cutaneous. Study 

(a) Tendons of insertion of Mm. sartorius, gracilis, and semitendinosus. 

(b) Great saphenous vein (V. saphena magna) (0. T. internal saphenous 

vein ) . 

(c) Branches of saphenous nerve (N. saphenus) (0. T. internal saphe- 

nous nerve). 

(ca) Infrapatellar branch (ramus infrapatellaris) . 

(cb) Medial cutaneous rami of leg (rami cutanei cruris mediales) . 

(d) Medial inferior artery of knee (A. genu inferior medialis) (0. T. 

inferior internal articular artery). 

(e) Tibial collateral ligament of knee-joint (Lig. collateral tibiale) (0. 

T. internal lateral ligament). 

POSTERIOR REGION OF LEG AND HEEL (REGIO 

CRURIS POSTERIOR ET REGIO CALCANEA) 

(0. T. POSTERIOR TIBIOFIBULAR REGION). 

Note how the leg tapers from above downward. The large, 
convex, fleshy upper half is known as the calf (sura). The lower 
half rapidly diminishes in size, so that the tibia and fibula may 
be felt as they pass into their respective malleoli. Behind each 
malleolus will be found a fossa. Flex the foot and extend it and 
note the play of tendons in each fossa. These fossae become 
obliterated in pathological processes involving the synovial mem- 
brane of the ankle-joint. Outline the stronger tendon (tendo 
calcaneus [Achillis] ) passing down to the os calcaneum. 

Superficial- Fascia of Leg. 

Make the muscles of the calf tense and continue the medial 



166 LABORATORY MANUAL OF HUMAN ANATOMY 

incision already made in the dissection of the fossa poplitea 
down to the heel; at the distal extremity of this make a trans- 
verse incision extending for five centimetres along the margo 
pedis lateralis and margo pedis medialis. Eeflect the flaps. 

Note the general characteristics of this fascia as regards the 
amount of fat contained, the general direction of its fibres, and 
the strength of the same. In it, dissect out carefully the fol- 
lowing : 

Veins. (Vide Spalteholz, Fig. 509.) 

(a) Small saphenous vein (vena saphena parva) (0. T. external saphe- 

nous vein). What is its relation to the malleolus lateralis? Note 
that it is the continuation of the lateral marginal vein of the 
foot (vena marginalis lateralis) into the leg. In the upper half 
of the leg this vein is ensheathed by a duplicature of the fascia 
cruris. Dissect out the two branches into which it bifurcates 
above and trace these out into the vena poplitea and the vena 
femoris profunda. What is the relation of the vena femoro- 
poplitea to the latter? Trace one of the perforating veins 
through the fascia cruris. Incise the vein longitudinally and 
determine whether it has valves or not. 

(b) Large saphenous vein (V. saphena magna) (0. T. internal saphe- 

nous). Determine its relation to the malleolus medialis. It is 
the continuation of the medial marginal vein (vena marginalis 
medialis) of the foot into the leg. Do you find a collateral vein 
accompanying it? When present, it will be found just posterior 
to the large vein. Incise the vein longitudinally and determine 
the characteristics of its valves. 

Nerves. (Fig. 69.) 

(a) Nerve of the calf (N. suralis) (0. T. short saphenous nerve). This 

nerve is formed by the union of the following: 

(aa) Medial cutaneous nerve of the calf (N. cutaneus surae 

medialis). In the greater part of its course this nerve 
will be found beneath the fascia cruris. At the middle 
of the leg it pierces this fascia to become subcutaneous. 

(ab) Anastomotic peroneal branch of the N. cutaneus surae 

lateralis (ramus anastomoticus peronaeus}. 

(b) Lateral cutaneous nerve of calf (N. cutaneus surae lateralis) (0. 

T. nervus communicans fibularis). 

(c) Posterior cutaneous nerve of thigh (N. cutaneus femoris posterior) 

(0. T. small sciatic). This nerve will be found beneath the fascia 
cruris. It sends twigs through the fascia to end in the skin. 

(d) Medial cutaneous branches (rami cutanei cruris mediales) to the 

leg from the N. saphenus. Determine the area of skin supplied 
by each nerve. 

Eemove the superficial fascia of the leg, and study the deep 
fascia. 



DISSECTION OF THE LOWER EXTREMITY 



167 



FIG. 69. 



N. tibialis I 



N. cutaneus femoris posterior^ 



Ramus cutaneus cruris medialis.-. 
of the N. saphenus 



HID 



[ N. peronaeus rommunte 

N. cutaneus surae medialis 
N. cutanuiis sunn- laU-ralis 

.. V. saphena parra 



N. cutaneus surae medialis 
(shining through) 



I- N. cutaneus surae medialis 

._ Ramus anastomoticus peronaeus 

._.N. suralis 
N. cutaneus dorsalis lateralis 



Kami calcanei laterales /' 



The cutaneus nerves of the posterior side of the leg. (After Toldt, Anat. Atlas, Wi,n, 1903, 
SAufl., p. M9, Fig. 1287.) 



168 LABORATORY MANUAL OF HUMAN ANATOMY 

Deep Fascia of Leg (Fascia cruris). 

This fascia extends from the knee to the malleoli. It repre- 
sents almost a complete cone, being interrupted only at the f acies 
medialis of the tibia. What is the relation of its superior cir- 
cumference to the capitulum fibulae, the condyles of the tibia, and 
the fascia lata? 

Its inferior circumference is attached to the malleoli and the 
tuber calcaneum. Between these three bony projections it 
becomes continuous with the annular ligaments about the ankle. 

Examine cross-sections of the leg and note the different 
relations of the fascial reflections and the osteofascial compart- 
ments formed by septa passing from this fascia into the tibia and 
fibula. They have already been referred to above. The septum 
intermusculare anterius [fibulare] and the septum intermuscu- 
lare posterius [fibulare] divide the sub fascial space into three 
compartments. (See Figs. 64 and 68.) 

(a) Anterior compartment, deep, prismatic in form. It lodges the M. 
tibialis anterior, the M. extensor digitorum longus, the M. extensor hal- 
lucis longus, the M. peronaeus tertius, and the anterior tibial vessels and 
nerves. 

(b) Lateral compartment: this lodges the peroneal muscles and the 
superior part of the nervus peronaeus superficialis. 

(c) Posterior compartment: this is divided into two secondary com- 
partments by the deep transverse fascia of the leg passing from the margo 
medialis of the tibia to the crista lateralis of the fibula. Posterior to this 
fascia will be found the M. triceps surae and the M. plantaris ; anterior to 
it will be found the M. tibialis posterior, M. flexor digitorum longus, M. 
flexor hallucis longus, the posterior tibial vessels and nerves, and the 
peroneal vessels. 

The fascia cruris varies much in thickness in different 
regions. It is composed of transverse longitudinal and oblique 
fibres. The transverse fibres arise from the crista anterior of 
the tibia and after encircling the leg are inserted upon the margo 
medialis of the same bone. The oblique and longitudinal fibres 
arise from the bony projections into which the superior circum- 
ference of this fascia is attached. What muscles send off proc- 
esses which reinforce the longitudinal and oblique fibres! 

Incise the fascia in the median line from the fossa poplitea 
to the os calcaneum and reflect the flaps. 

Muscles of the Superficial Posterior Osteofascial Compartment. 
These may now be dissected out. 

The muscles of the leg find their homologues in the muscles of the fore- 
arm. Any differences found are to be explained by the adaptation of the 



DISSECTION OF THE LOWER EXTREMITY 169 

leg muscles to locomotion. The relative atrophy of the motor system of 
the toes is due to the loss of its femoral attachment and to a displacement 
of the flexors and extensors, deprived of their tibial and fibular attach- 
ments, downward into the intrinsic musculature of the foot. The pro- 
nator and supinator systems are almost absent, being represented by the 
popliteus alone, and this through skeletal modifications has lost its primi- 
tive role. The muscles of the leg, like those of the forearm, are delimited 
into an anterior, a posterior, and a lateral group by the bones of the leg 
and aponeurotic septa. 

Study carefully the origin, insertion, form, action, and inner- 
vation of the following muscles : 

(a) Triceps muscle of the calf (M. triceps surae). (Vide Spalteholz, 

Figs. 393-94.) 

(aa) Gastrocnemius muscle (M. gastrocnemius) . 

(aaa) Lateral head (caput laterale). Look for a small 

sesamoid cartilage or bone in this head. Observe 
the lateral bursa of the gastrocnemius (bursa M. 
gastrocnemii lateralis) and the bursa bicipitogas- 
trocnemialis. 

(aab) Medial head (caput mediale). Observe the medial 

bursa of the gastrocnemius (bursa M. gastrocnemii 
medialis) and the bursa M. semimembranosi. Dis- 
sect this bursa out carefully and determine whether 
or not it communicates with the joint-cavity. 
Divide the gastrocnemius transversely near its attachment to 
the tendo Achillis and reflect it upward, preserving vessels and 
nerves passing into each head, and study the muscle beneath the 
M. gastrocnemius. 

(ab) Soleus muscle (M. soleus). (Vide Spalteholz, Fig. 394.) 

'Determine its exact origin from the fibula and 
tibia. Note that the tendon of this muscle fuses 
with the tendon of the gastrocnemius to form 
the 
(aba) Tendo calcaneus [Achillis]. 

Divide the soleus transversely at the level at 
which it joins the gastrocnemius. Incise the belly 
of the soleus in the middle line and expose the 
tendinous arch (arcus tendineus M. solei) and the 
blood-vessels and nerves entering the muscle. 
The plantaris muscle may be divided to permit of 
the turning of the tendo calcaneus [Achillis] 
downward. Determine its exact attachment to the 
os calcaneum and study the following bursae : 

(1) Bursa subcutanea calcanea. (Vide Spalte- 

holz, Fig. 393.) 

(2) Bursa tendinis calcanea. (Vide Spalteholz, 

Fig. 395.) 

(b) Plantaris muscle (M. plantaris). (Vide SpaKaholz, Ffe. J 

tendon of this small muscle has already been divided to P-n 



170 LABORATORY MANUAL OF HUMAN ANATOMY 

the turning of the tendo calcaneus [Achillis] downward. Deter- 
mine its insertion. It is the homologue of the palmaris longus in 
the forearm. In monkeys, whose feet are prehensile, it is the 
proper tensor muscle of the plantar fascia. It is well developed 
in all plantigrade animals. 

Deep Transverse Fascia of Leg and Structures beneath it. 

Note its attachment medially to the tibia and laterally to the 
fibula. Trace the fascia downward to the ankle, where it becomes 
thickened to form the ligamentum laciniatum (0. T. internal an- 
nular ligament). (Vide Spalteholz, Fig. 395.) Incise this fascia 
longitudinally, leaving the Lig. laciniatum intact, and proceed to 
the study of the structures beneath it. 

Muscles. Note carefully the form, position, origin, insertion, action, and 
innervation of each. (Vide Spalteholz, Fig. 395.) 

(a) Popliteus muscle (M. popliteus). Determine the relation of its 

tendon to the capsule of the knee-joint and the ligamentum pop- 
liteum arcuatum. Note the dense aponeurosis covering this 
muscle. It receives a strengthening band from the tendon of the 
semimembranosus muscle. Examine the bursa of the popliteus 
muscle (bursa M. poplitei}. (Vide Spalteholz, Fig. 396.) Does 
this bursa communicate with the knee-joint? 

(b) Long flexor of the digits (M. flexor digitorum longus). (Vide 

Spalteholz, Fig. 395.) Examine the sheath of the long flexor 
tendons of the toes (vagina tendinum M. flexoris digitorum pedis 
longi). This sheath surrounds the tendon as it passes behind the 
malleolus medialis and is continued well down into the foot. 
Does it communicate with a sheath which surrounds the tendons 
of the tibialis posterior and the flexor longus hallucis? 

(c) Posterior tibial muscle (M. tibialis posterior] (0. T. tibialis pos- 

ticus). This muscle may be more or less fused with the long 
flexors, which is only an exaggeration of the normal disposition 
in man and a reproduction of the normal disposition in the cat. 
( Strauss-Diirckheim. ) 

Examine the sheath of the tendon of the M. tibialis posterior 
(vagina tendinis M. tibialis posterioris) . 

(d) Long flexor of the great toe (M. flexor hallucis longus). Examine 

the sheath of the tendon of the long flexor of the great toe 
(vagina tendinis M. flexoris hallucis longi). 

At this stage in the dissection examine the bony leg and foot. 
Determine the exact position of the sulci through which these 
tendons pass. Note the exact relation of the tendons beneath 
the ligamentum laciniatum. (See Fig. 71.) 

Varieties in the flexor system of the foot are frequent. The 
tendency to differentiate may be accentuated, but more fre- 
quently there is a return to the primitive undivided mass arising 



DISSECTION OF THE LOWER EXTREMITY 
FIG. 70. 



171 



A. poplitea 

( med. sup. 
Aa. genu < 

\- lat. sup. 






Aa. surah 



f 



A. genu inf. lat. 
A. tibialis ant.^ 
A. peronaea 

A. tibialis post.. 



A. malleolaris post. lat.. 
A. malleolaris post. med.. 

Rete calcan.. 



Arteries of the posterior part of the leg. 

The muscles of the calf have been removed. The A. peronaea is represented as showing through 
the muscle lying over it. (From Gegenbaur. Lehrb. der Anat. des Mt,-ii-<-h.. Leipzig, 1899. 7 Aufl.. Bd. 
ii. p. 295, Fig. 548.) 



172 LABORATORY MANUAL OF HUMAN ANATOMY 

from the tibia and fibula. In the lower forms, such as the rabbit 
and kangaroo, this primitive undivided mass of flexors is the 
rule. 

Arteries. (Vide Fig. 70, and also Spalteholz, Fig. 478.) 

Trace the popliteal artery downward, and note that it bifurcates 
just anterior to the arcus tendineus M. solei into the anterior and 
posterior tibial arteries. The anterior tibial has already been dis- 
sected. Trace out the course of the posterior tibial artery. Determine 
the course and position of its linear guide. Where would you take 
the pulse in the leg and foot? Study 
(a) Posterior tibial artery (A. tibialis posterior}. 

(aa) Fibular branch (ramus fibularis). 

(ab) Peroneal artery (A. peronaea). 

(1) Nutrient artery of the fibula (A. nutricia fibulae). 

(2) Perforating branch (ramus perforans). 

(3) Communicating branch (ramus communicans) . 

(4) Lateral posterior malleolar artery (A. malleolaris 

posterior lateralis). 

(5) Lateral calcanean branches (rami calcanei later ales). 

(ac) Nutrient artery of the tibia (A. nutricia tibiae). 

How are the nutrient arteries of the lower extremities 
directed ? 

(ad) Medial posterior malleolar artery (A. malleolaris posterior 

medialis) (0. T. internal malleolar). 

(ae) Medial calcanean branches (rami calcanei mediates). 

(af) Network of heel (rete calcaneum). 

The terminal branches of the A. tibialis posterior will 
be found when the dissection of the foot is made. 

Trace out the veins accompanying this artery and de- 
termine their anastomoses and the large veins into which 
they empty. 

Nerves. (Spalteholz, Fig. 823.) 
(a) Tibial nerve (N. tibialis). 

(aa) Muscular branches (rami muscular es). 

(ab) Interosseous nerve of the leg (N. inter osseus cruris). 

(ac) Medial cutaneous nerve of the calf (N. cutaneus surae 

medialis). This nerve has already been dissected. It 
unites with the ramus anastomoticus peronaeus to form 
the 

(ad) Nerve of the calf (N. suralis). 

(ada) Lateral calcanean branches (rami calcanei lat- 

erales). 

(adb) Lateral dorsal cutaneous nerve of the foot (N. 

cutaneus dorsalis lateralis pedis). This nerve 
is the continuation of the N. suralis into the 
foot. Review at this stage of the dissection the 
cutaneous nerve supply of the dorsum of the 
foot. 

(ae) Medial calcanean branches (rami calcanei mediales) . 

Dissect out the branch passing into the syndesmosis 
tibiofibularis. Do you find any branches accompanying 
the A. tibialis posterior? 



DISSECTION OF THE LOWER EXTREMITY 173 

Make a drawing showing the structures exposed and their 
exact relations at different levels. Pay especial attention to the 
relations of the structures in the fossa retromalleolaris medialis. 

Laciniate (" Fringed") Ligament (Ligamentum laciniatum) (O. T. 
Internal Annular Ligament). (Fig. 71.) 

Determine the different points of attachment of this fibrous 
triangular lamina and the relation that they bear to the malleolus 
medialis, the medial surface of the tuber calcanei, the medial 

FIG. 71. 




M. flexor digit, longus, 

M. flexor hallucis longus 

M. tibialis posterior, 

M. tibialis anterior. 

Lig. cruciat. cruris y 



. lai-iniatum 



I 

M. flexor hall, brevis 

Margo pedis medialis, showing the tendons of the muscles of the leg. (From Gegenbaur, Lehrb. 
der Anat. des Mensch., Leipzig, 1899, 7 Aufl., Bd. i. p. 468, Fig. 340.) 

plantar aponeurosis, the abductor hallucis muscle, and the fascia 
cruris. It covers the tendons of the tibialis posterior, the flexor 
digitorum longus, and the flexor hallucis longus muscles, and 
the posterior tibial vessels and nerves. Each of these struct im 
runs within a special sheath. The tibialis posterior and 
flexor digitorum longus are separated from each other by 
fibrous septum which passes off from the deep surface of 
ligament. The fibres constituting the septum pass beneath 
tendons; one process, ascending, is attached to the 



174 LABORATORY MANUAL OF HUMAN ANATOMY 

medialis and the ligamentum deltoideurn ; the other, descending, 
is attached to the processus medialis tuberis calcanei. 

The tendon of the long flexor of the great toe is contained 
within a special sheath, altogether independent of the ligamen- 
tum laciniatum. The fibres of this sheath arise from the medial 
tip of the sulcus M. flexoris hallucis longi and from the summit 
of the sustentaculum tali. They terminate upon the medial tip 
of the same sulcus and the medial face of the os calcaneum about 
one centimetre below the sustentaculum tali. The vessels run 
above this sheath covered by the ligament, but generally the 
medial and plantar arteries are separated from each other by a 
septum. 

Detach the ligament from the malleolus medialis and dissect 
it towards the os calcaneum, determining its exact attachment 
and the position of the septa above mentioned. Make a drawing 
of these structures at this stage of the dissection. 



PLANTAR EEGION OF THE FOOT (EEGIO PLAN- 
TAEIS PEDIS). 

Before beginning this dissection, review the anatomy of the 
bones entering into the formation of the foot. Note the number 
and the exact position of each. (Vide Spalteholz, Figs. 198-99.) 
Study in the bony foot and upon your subject the following : 

Arches. 

(a) Longitudinal arch. This arch extends from the heel to the meta- 
tarsophalangeal joints. It is capped by the talus and 
may be divided into 

(aa) A posterior limb, formed by the os calcaneum and the pos- 

terior part of the talus. Note the thickness and the 
strength of this posterior limb, which serves as a point 
of attachment for the tendo calcaneus [Achillis]. Study 
the skeletons of the white, the negro, and the monkey 
and compare the relative lengths of this posterior limb. 

(ab) An anterior limb. This limb is formed by the remaining 

bones of the tarsus and metatarsus. Examine a model 
of a foot in which the joint-cavities are represented, and 
note the amount of synovial membrane found in the 
joints of the anterior limb. These membranes produce 
an elastic resistance to any force applied to the anterior 
limb of the longitudinal arch. Shocks transmitted 
through it to the leg, pelvis, and trunk are much lessened 
by this arrangement. The anterior limb is subdivided 
into a medial pillar, formed by the talus, the navicular, 
the three cuneiform, and the three medial metatarsal 



DISSECTION OF THE LOWER KXTIiK.MITV 

bones, and a lateral pillar, formed by the calcam-mn, 
the cuboid, and the two lateral metatarsal bones. 

(b) Transverse arch. Where is this arch to be found and what function 

does it subserve? 

(c) Lateral arch. This arch is convex laterally and extends from the 

heel to the base of the little toe. Determine in what directions 
pressure exerted from above is radiated by this arrangement of 
the arches. What factors assist in the maintenance of the aivh 
of the foot? Study, in this connection, especially the tendon 
of the M. peronaeus. What is flat-foot? Where is the sprin.i: 
of the foot? In flat-foot the line of tenderness generally corre- 
sponds to the line of Chopart's joint. 

Examine the medial margin of the foot and determine the 
position of the following : 

(a) Sustentaculum tali. 

(b) Tuberositas ossis navicularis. 

(c) Line of calcaneo-astragaloid joint (articulatio talocalcanea) . 

(d) Line of tarsometatarsal joints (articulationes tarsometatarseae) . 

(e) Lines of metatarsophalangeal joints (articulationes metatarsopha- 

langeae). 

Examine upon the lateral margin of the foot 

(a) Trochlear process (processus trochlearis) , not always present. 

(b) Line of calcaneocuboid joint (articulatio calcaneocuboidea) . In con- 

nection with Chopart's amputation it is important to know the 
structures which serve as guides in finding the mid-tarsal joint. 

(c) Tuberositas ossis metatarsalis. What is its relation to the articula- 

tiones tarsometatarseae? What is Lisfranc's ligament? (Vide 
Cunningham's Systematic Anatomy, p. 1218.) 

Examine now the skin covering the sole of the foot. Note its 
general characteristics and compare it with the skin of the palm 
of the hand. How does it compare with the skin over the dorsum 
of the foot ! Which is the more mobile, and which is the thinner ? 
Note the callosities that form about the heel and the ball of the 
toes. In standing which parts of the sole come in contact with 
the floor? 

The foot should be firmly fixed and the toes extended, thus 
rendering the plantar aponeurosis tense. Make the following 
incisions : 

(1) A perpendicular incision extending down the middle of the sole. 

(2) A transverse incision across the sole at the clefts of the toes. 

(3) A medial incision extending the length of each toe. 

Reflect the flaps of skin and study the fascia beneath. 



176 LABORATORY MANUAL OF HUMAN ANATOMY 

Superficial Fascia of Sole. 

This fascia consists of but one layer, and resembles the fas- 
ciae of the palm of the hand and of the scalp. Note the peculiar 
character of the fat and its disposition. Thick fibrous processes 
will be found which connect this fascia to the skin. Dissect away 
this fascia carefully and study the following: 

Bursae. 

(a) Subcutaneous calcanean bursa (bursa subcutanea calcanea). (Vide 

Spalteholz, p. 348.) 

(b) Bursa in the ball of the great and of the little toe. Occasionally a 

small artery and nerve may be found passing into these bursae. 
When inflamed they are very painful. How may the formation 
of these subcutaneous bursae be accounted for? 
Veins. 

(a) Digital plantar veins (Vv. digitales plantar es}. 

(b) Plantar venous arch (arcus plantaris venosus). 

(ba) Intercapitular veins (Vv. inter capitular es} , single or dou- 
ble, passing between each pair of toes to join the Vv. 
digitales dorsales. 

(c) Plantar venous network (rete venosum plantare). 

Determine the exact course of the venous blood coming from the sole 
of the foot. 
Nerves. 

(a) Medial calcanean branches of the tibial nerve (rami calcanei N. 

tibialis). 

(b) Cutaneous branches of the plantar nerves. 
Lymphatics. 

Determine the exact course of the lymphatics of the sole of the foot. 
(Vide Toldt, Fig. 1090.) 

Plantar Aponeurosis (Aponeurosis plantaris.) 

Eemove now the superficial fascia and study the aponeurosis 
plantaris. (Vide Spalteholz, Fig. 397.) 

Note the density of this aponeurosis. It is attached poste- 
riorly to the os calcaneum and passes forward to cover the whole 
of the musculature of the foot. It is attached to the medial and 
lateral margins of the foot, and passes without interruption into 
the fascia of the dorsum of the foot. 

This aponeurosis, like the palmar aponeurosis, may be 
divided into a middle, a medial, and a lateral part. How does 
the strength of the middle part compare with that of the medial 
and lateral parts'? Trace this medial part forward, after having 
determined its posterior attachment; dissect out the five proc- 
esses into which it divides. Determine their relations to the 
Ligg. vaginalia and the phalanges. Dissect out carefully the 
transverse bundles (fasciculi transversi). 



DISSECTION OF THE LOWER EXTREMITY 177 

The medial part is the weakest. It is continuous posteriorly 
with the ligamentum laciniatum, and is attached along the medial 
margin of the foot to the tarsal and first metatarsal bones. What 
muscles does this part cover! 

The lateral part is stronger than the medial. It is attached 
behind to the lateral tubercle of the os calcaneum and in front 
to the tuberosity and the lateral border of the fifth metatarsal. 
Posteriorly all three divisions give origin to muscles. 

From the deep surface of the plantar aponeurosis a medial 
and a lateral process are given off, which pass downward to fuse 
with the fascia interossea plantaris and to become attached to the 
tarsal bones. Three separate muscular compartments are thus 
formed. These septa may be seen if the plantar aponeurosis be 
incised in the median line from heel to toe and reflected each way. 

Contraction of the plantar fascia gives rise to the condition 
known as pes cavum. The division of the aponeurosis is most 
easily accomplished one inch in front of its attachments to the 
os calcaneum, where it is narrowest. Pus may collect beneath 
the fascia, and it is apt to burrow, because the aponeurosis is so 
dense that pus cannot perforate it. Occasionally pus may pass 
through one of the small foramina formed by the passage of 
small arteries and nerves through the aponeurosis. In this case 
two abscess-cavities will be formed. Such a condition is known 
as the abces en bissac. 

Eemove the aponeurosis plantaris and study the structures 

beneath. 

FIG. 72. 

J M. flexor dig. 

M. flexor hall, long 



Caput plantare 

\\< 




/ 

J 2 



Relation of the tendons of the M. flexor digitoruin longus and of the M flexor halhieis longus x*n 
from the upper side. (From Gegenbaur, Lehrb. der Anat. des Mensch., Leipzig, 1H99, / 
Fig. 339.) 

Superficial Layer of Muscles of the Sole. (Vide Spalteholz, Fig. 398.) 
Note the form, position, origin, insertion, action, and inner- 

vation of each. 

12 



178 LABORATORY MANUAL OF HUMAN ANATOMY 

(a) Short flexor muscle of the toes (M. flexor digit orum brevis). Exam- 

ine its ligamentous sheath (ligamentum vaginale), annular ligament 
(ligamentum annular e), and the cruciate ligament (ligamentum 
cruciatum ) . 

After having made a careful study of this ligamentous sheath, 
incise it in the medial line and reflect each way, preserving care- 
fully the vessels and nerves. Note the synovial sheath (vaginae 
tendinum digitales pedis) surrounding the flexor tendons. (Vide 
Spalteholz, Fig. 407.) What relations exist between the tendons 
of the long and of the short flexors of the toes? Compare these 
relations with those found in the hand. 

(b) Abductor muscle of great toe (M. abductor hallucis}. 

(c) Abductor muscle of little toe (M. abductor minimi digiti). 

Divide these muscles at their origin and reflect them forward. Exercise 
great care and avoid injury to yessels and nerves immediately beneath. 

Plantar Arteries. (Vide Spalteholz, Fig. 481.) 

Determine the relations of these different arteries. What is 
the linear guide for each artery ? All the branches are mentioned 
here, although many will not be seen at this stage of the dis- 
section. 

(a) Medial plantar artery (A. plantaris medialis) (0. T. internal plan- 

tar). 

(aa) Superficial branch (ramus super ficialis) . 

(ab) Deep branch (ramus profundus). 

(b) Lateral plantar artery (A. plantaris lateralis) (0. T. external plan- 

tar). 
(ba) Plantar arch (arcus plantaris). 

(baa) Plantar metatarsal arteries (Aa. metatarseae plan- 

tares). 

(bab) Perforating branches (rami perforantes) . 

(bac) Digital plantar arteries (Aa. digitales plantar es). 
With what arteries do the above anastomose? Dissect out the veins 

accompanying the arteries and trace them into larger stems. 

Plantar Nerves. (Vide Spalteholz, Figs. 824 and 825.) 

Determine what muscle is supplied by each nerve, also the 
exact cutaneous supply. What is muscle sense! 

(a) Medial plantar nerve (N. plantaris medialis) (0. T. internal plantar). 

(aa) Common digital plantar nerves (Nn. digitales plantar es com- 

munes). 

(ab) Proper digital plantar nerves (Nn. digitales plantar es pro- 

prii). 

(b) Lateral plantar nerve (N. plantaris lateralis) (0. T. external plan- 

tar). 
(ba) Superficial branch (ramus superficialis) . 

Common digital plantar nerves (Nn. digitales plantar es 
communes). 



DISSECTION OF THE LOWER EXTREMITY 179 

Proper digital plantar nerves (Nn. digitales plantar -es 

proprii). 
(bb) Deep branch (ramus profundus). 

Second Layer of Muscles and Tendons of the Sole. 

(a) Tendons of the M. flexor digitorum longus. 

(aa) Quadrate muscle of the sole (M. quadratics plantae) (0. T. 

accessorius muscle). (Fig. 72.) 

Two planes of fibres will be found in this muscle. Dis- 
sect both out carefully and determine their relations to the 
different tendons. 

(ab) Lumbrical muscles (Mm. lumbricales) . Determine the exact 

modes of origin from the tendons of the long flexor and 
trace them forward to the tendons of the long extensor. 
These little muscles act chiefly through the above tendons 
and produce, when active, a flexion of the first phalanx and 
extension of the second and third. Dissect out the bursae 
Mm. lumbricalium pedis. 

(b) Tendon of the long flexor of the great toe. Determine the relative 

position of this tendon and dissect out the tendinous process pass- 
ing over to the tendon of the long flexor of the digits. 

Divide the tendons of the M. flexor longus digitorum, M. 
flexor longus hallucis, M. quadratus plantae, and the plantar ves- 
sels and nerves near the os calcaneum and reflect them down- 
ward. 



Third Layer of Muscles of the Sole. (Vide Spalteholz, Fig. 400.) 

(a) Short flexor muscle of great toe (M. flexor hallucis brevis). 

(b) Adductor muscle of great toe (M. adductor hallucis). 

(ba) Oblique head (caput obliquum). 

(bb) Transverse head (caput transversum). 

(c) Short flexor muscle of fifth toe (M. flexor digiti quinti brevis). 

(d) Opposing muscle of little toe (M. opponens digiti quinti). 

Sever the M. flexor digitorum brevis and the caput obliquum 
of the M. adductor hallucis at their origins and reflect them 
downward. Complete now the study of the arcus plantaris. De- 
termine where the deep branch of the dorsal artery of the foot 
passes into the planta. Note the deep branch of the lateral 
plantar nerve close by the arch. 

Displace the digital vessels and nerves forward and sever t 
short flexor of the little toe and the transverse head of 
adductor hallucis at their origins and reflect. Note the strong 
bands of fibrous tissue (ligamentum capitulorum transversum) 
passing between the heads of the metacarpal bones. 



180 LABOKATORY MANUAL OF HUMAN ANATOMY 

Fourth Layer of Muscles of the Sole. 

(a) Plantar interosseous muscles (Mm. inter ossei plantar es). 

(b) Dorsal interosseous muscles (Mm. inter ossei dor sales). 

Determine the form, position, origin, insertion, action, and 
innervation of each, and compare them with their homologues in 
the hand. Note that they are covered by a thin layer of inter- 
osseous fascia (fascia interossea). 

The points of insertion of the M. tibialis posterior will now 
be exposed. Dissect out the different reflections of its tendons 
and determine to what bones each is attached. 

Dissect out the tendon of the M. peronaeus longus. Note 
that it runs in a sulcus covered over by the ligamentum longum 
plantae. Dissect down to the tendon and trace it to its insertion, 
noting the plantar synovial sheath (vagina tendinis M. peronaei 
longi plant aris). (Vide Spalteholz, Fig. 407.) What role does it 
play in maintaining the arch of the foot 1 



JOINTS OF THE LOWER EXTREMITY. 

The hip- joint has been studied already. The other joints 
should now be carefully dissected. 

Arterial Anastomosis about the Knee-joint. 

Before dissecting the knee-joint, review the various blood- 
vessels about the knee and study the most important anasto- 
moses. (Fig. 73.) 

Knee-joint (Articulatio genu). (Figs. 73-77.) 

Remove the popliteal vessels and nerves. The tendons of the 
muscles surrounding the joint should be left in place, so that 
their relations to the different ligaments may be studied. Divide 
the M. quadriceps extensor about eight centimetres above the 
patella and allow the lower part to remain in situ. Trace each 
of the articular arteries to its termination. Study the following : 

(a) Articular capsule (capsula articularis) . 

(b) Fibular collateral ligament (Lig. collaterale fibulare) (0. T. long 

external ligament). 

(c) Tibial collateral ligament (Lig. collaterale tibiale) (0. T. internal 

lateral ligament). 

(d) Oblique popliteal ligament (Lig. popliteum obliquum) (0. T. pos- 

terior ligament). 

(e) Arcuate popliteal ligament (Lig. popliteum arcuatum). 

Observe the retinaculum Lig. arcuati. 



DISSECTION OF THE LOWER EXTREMITY 

(/) Ligament of the patella (Lig. patellae}. 

(fa) Retinaculum patellae mediale. 

(fb) Retinaculum patellae laterale. 



181 



Fie. 73. 



A. genu sup. lat. 



A. genu inf. lat. .. 
A. rec. tib. post. 

V 

Ramus flb. A. tib. post. - 




A. genu suprema 



..A. genu sup. med. 



....A. genu inf. med. 
-A. rec. tib. ant. 



A. tibialis anterior 



Arterial anastomosis about the knee. (After Poirier et Charpy, 
Traite d'Anat hum., Paris, 1901, 2 ed., t. ii. p. 831, Fig. 449.) 



Make a vertical incision into the joint on either side of the 
patella and ligamentum patellae. The common extensor ten- 
don and the patella should now be thrown downward and the 
following internal structures studied : 

(g) Lateral meniscus (meniscus lateralis) (0. T. external semilunar fibro- 

cartilage ) . 
(h) Medial meniscus (meniscus medialis) (0. T. internal semilunar fibro- 

cartilage). 

(i) Transverse ligament of the knee (Lig. transfer sum genu). 
(j) Crucial ligaments of the knee (Ligg. cruciata genu). 

(ja) Anterior crucial ligament (Lig. cruciatum anterius). 

(jb) Posterior crucial ligament (Lig. mirintinu postrriii*). 
(k) Patellar synovial fold (plica synovialis patellaris) (0. T. ligamentum 

mncosum ) . 

What is the significance of this fold? 
(0 Alar folds (plicae alares) (0. T. ligamenta alaria). 



182 



LABORATORY MANUAL OF HUMAN ANATOMY 



Study with care the reflections of the synovial membrane. It 
is the most extensive of any in the body, and is of great practical 
importance because of its frequent involvement in disease. 

Look for " loose bodies" in the cavity of the knee-joint; 
occasionally one is found. Eemember that in a Rontgen-ray 



Tend. M. quad, fern 



Lig. proprium 
pat. med. 



Meniscus medialis 



FIG. 74. 



Tend. M. adduct. mag. 



B. infrapat. prof. .- 
A. genu iuf. med. .. 




. M. semimemb. 



[ Lig. collat. tib. 



..M. gastroc. (caput 
med.) 



Articulatio genu, medial view. The capsula articularis is removed to demonstrate its lines of 
attachment to the feimir and tibia. (From Poirier et Charpy, Traite d'Anat. hum., Paris, 1899, 2 ed., 
t. i. p. 737, Fig. 739.) 



picture the sesamoid bone in the origin of the M. gastrocnemius 
has before now been mistaken for such a i i loose body. ' ' 

Having charted the length and breadth of the muscular 
attachments on the tibia and fibula, remove the muscles and 
study the articulation between the bones. 



DISSECTION OF THE LOWER EXTREMITY 183 



Lig. ant. men. med. ... 



Meniscus medialis_ 
Lig. post. men. med. . 



FIG. 75. 

Lig. transversum 




.. Lig. ant. men. lat. 
Lig. cruoiatum ant. 
.Lig. post. men. lat. 
. Meniscus lateralis 



Lig. cruciatum post. 

Condylus medialis et lateralis with menisci. (From Poirier et Charpy, Traits 
d'Anat. hum., Paris, 1899, 2 ed., t. i. p. 733, Fig. 737.) 



FlG. 76. 



Lateral intertrochleo-. 
condylar groove 



Lig. cruciatum. 
anterius 



Lig. collat. nbulare- 




Medial intertrochleo- 
condylar groove 



Lig. cruciatum post. 



Lig. transversum genu 



Lig. collat. tibiale 



Crucial ligaments of the knee (Ligg. cruciata genu) ; anterior view. The femur is flexed at right angles 
to the tibia. (From Poirier et Charpy, Traite d'Anat. hum., Paris, 185W, t. i. p. 74U, h i 



184 



LABORATORY MANUAL OF HUMAN ANATOMY 



Tibiofibular Articulation (Articulatio tibiofibularis) (O. T. Superior 
Tibiofibular Articulation). (Fig. 78.) 

(a) Articular capsule (capsula articularis) . 

(b) Ligaments of the head of the fibula (Ligg. capituli fibulae) (0. T. 

anterior and posterior superior tibiofibular ligaments). 

(c) Interosseous membrane of leg (membrana interossea cruris) (0. T. 

middle tibiofibular ligament). 



FIG. 77. 



Supracondylar process 



Tendon M. poplitei -.- 



BursaM. poplitei ... 




B. suprapatellaris 



- Cavum articulare 



^.. Notch due to adipose mass 



Inferior compartment 



Synovial spaces of the articulatio genu, lateral view. (From Poirier et Charpy, 
Trait6 d'Anat. hum., Paris, 1899, 2 ed., t. i. p. 744, Fig. 745.) 

Tibiofibular Syndesmosis (Syndesmosis tibiofibularis) (O. T. Inferior 

Tibiofibular Articulation). 
Study- 

(a) Anterior ligament of lateral malleolus (Lig. malleoli lateralis ante- 

rius). 

(b) Posterior ligament of lateral malleolus (Lig. malleoli lateralis pos- 

terius ) . 



DISSECTION OF THE LOWER EXTREMITY 



L85 



After the ankle-joint has been studied, the tibia and fibula 
should be sawn through about five centimetres above their lower 
articular surfaces. Make a coronal section of the bones and 
study the ligament passing between their lower extremities. 
Establish the continuity of the synovial membrane of this joint 
with that of the ankle. 

Remove the crucial ligament of the leg and the transverse 
ligament of the foot, also the tendons passing over the ankle, 
and dissect out the joints of the foot. 

FIG. 78. 



.A. rec. tib. ant. 



.A. tib. ant. 



.Memb. interos. 



.Ramus perf. A. peron. 



.A. tib. ant. 



Membrana interossea cruris. (After Poirier et Charpy, Tralt6 
d'Anat. hum., Paris, 1899, 2 ed., t. i. p. 756, Fig. 755.) 

Articulations of the Foot (Articulationes Pedis). (Figs. 
79-82.) 

Talocrural Articulation (Articulatio talocruralis) (Ankle-joint). 

In removing the soft parts in order to expose the joint, take 
great care not to injure the very delicate anterior part 
articular capsule. 



186 



LABORATORY MANUAL OF HUMAN ANATOMY 



(a) Articular capsule (capsula articular is ). 

(b) Deltoid ligament (Lig. deltoideum) (0. T. internal lateral ligament 

and anterior and posterior tibiotarsal ligaments). 

(ba) Tibionavicular ligament (Lig. tibionavi culare ) . 

(bb) Calcaneotibial ligament (Lig. calcaneotibiale). 

(be) Anterior talotibial ligament (Lig. talotibiale anterius). 
(bd) Posterior talotibial ligament (Lig. talotibiale posterius). 

(c) Anterior talofibular ligament (Lig. talofibulare anterius) (0. T. 

anterior fasciculus of external lateral ligament). 

(d) Posterior talofibular ligament (Lig. talofibulare posterius) (0. T. 

posterior fasciculus of external lateral ligament). 

(e) Calcaneofibular ligament (Lig. calcaneofibulare) (0. T. middle 

fasciculus of external lateral ligament). 

FIG. 79. 




Lig. talotibiale post. 
Lig. talocalc. post. 



j. naviculari- 
cuneiforme dorsale 



Lig. tibio- 
calcaneum 



Articulationes talocruralis et intertarseae. Medial view. (From Poirier et Charpy, Trait< 
d'Anat. hum., Paris, 1899, 2 ed., t. i. p. 761, Fig. 759.) 



The articular capsule should be opened anteriorly and poste- 
riorly after it has been cleaned. When opened, a good view of 
the interior of the joint may be had and the remaining ligaments 
more easily defined. 

Study sagittal and frontal sections through this joint on 
preparations in the anatomical museum; examine closely the 
relations of the ligaments and the folds of the capsule to the 
joint-cavity. 

Clean away all the muscles and tendons upon the foot, after 



DISSECTION OF THE LOWER EXTREMITY 



187 



the length and breadth of their attachments have been charted, 
and study the following joints. 



Intertarsal Articulations (Articulationes intertarseae). 

Taloealcaneonavicular Articulation (Articulatio talocalcaneonavicularis) . 

This is the more anterior of the two separate joint-cavities 
which exist between the talus on the one hand and the navicular 
bone and the calcaneus on the other. The posterior of the two 
joint-cavities is called the articulatio calcanea. (See Spalteholz, 
Fig. 271.) 

FIG. 80. 



Inferior tibiofibular 

interosseous 

ligament 



Lig. malleoli lateralis anterius 



Lig. talofibulare ant. 

Lig. talonaviculare [dorsale] 




Lig. calc. 
cuboi(f dorsale 



Lig. cuboideonavieulare dorsale 



Lig. naviculari- 
cuneifonn. dors. 



. !,, ( Pars calcaneo- 

-Lig.bifur-l navi( . ularis 

rr , t : atn . , 1 Pars mlouiro- 
cuboid. -a 



Lig. talocalc. 

Lig. calc.-flbulare lat " 

Articulationes talocruralis et intertarseae. Lateral view. (From Poirier etCharpy, Truite 
d'Anat. hum., Paris, 1899, 2 ed., t. i. p. 760, Fig. 758.) 

Study now : 

(a) Talocalcanean articulation (articulatio talocalcanea) . 

(aa) Articular capsule (capsula articularis) . 

(ab) Lateral talocalcanean ligament (Lig. talocalcaneum lat- 

erale) (0. T. external calcaneo-astragaloid ligament) 

(ac) Medial talocalcanean ligament (Lig. talocalcaneum medialc) 

(0. T. internal calcaneo-astragaloid ligament). 

(ad) Anterior talocalcanean ligament (Lig. talocalcaneum ante- 

rius). 

(ae) Posterior talocalcanean ligament (Lig. talocalc 

(b) Chopart's Inverse articulation of the tarsus (articulatio tarsi 

transversa [ Choparti] ) . 



188 LABORATORY MANUAL OF HUMAN ANATOMY 

This demands particular attention because it is of 
great importance to the surgeon. Chopart's amputation 
of the foot is made through this joint. Besides, the pain 
of flat-foot is localized in this joint. 

(ba) Talonavicular articulation (articulatio talonavicularis) . 

Observe that this is really only a part of the 
articulatio talocalcaneonavicularis. 
(baa) Articular capsule (capsula articularis) . 

(bb) Calcaneocuboid articulation (articulatio calcaneocuboidea). 

(bba) Articular capsule (capsula articularis). 

(c) Cuneonavicular articulation (articulatio cuneonavicularis) . 

(d) Interosseous ligaments of tarsus (Ligg. tarsi interossea). 

(da) Interosseous talocalcanean ligament (Lig. talocalcaneum 

interosseum ) . 

(db) Interosseous cuneocuboid ligament (Lig. cuneocuboideum 

interosseum ) . 

(dc) Interosseous intercuneiform ligaments (Ligg. inter cunei- 

formia interossea). 

(e) Dorsal ligaments of tarsus (Ligg. tarsi dorsalia). 

(ea) [Dorsal] talonavicular ligament (Lig. talonaviculare [dor- 

sale]) (0. T. superior astragalonavicular ligament). 

(eb) Dorsal cuneocuboid ligament (Lig. cuneocuboideum dor- 

sale). 

(ec) Dorsal cuboideonavicular ligament (Lig. cuboideonavicu- 

lare dorsale). 

(ed) Bifurcate ligament (Lig. bifurcatum). 

(eda) Calcaneonavicular part (pars calcaneonavicularis) 

(0. T. superior or external calcaneonavicular 
ligament ) . 

(edb) Calcaneocuboidal part (pars calcaneocuboidea) 

(0. T. internal calcaneocuboid ligament). 

(ee) Dorsal calcaneonavicular ligament (Lig. calcaneonavicular e 

dorsale). 

(ef) Dorsal navicular cuneiform ligaments (Ligg. naviculari- 

cuneiformia dorsalia). 

(f) Plantar ligaments of tarsus (Ligg. tarsi plantaria). 

(fa) Long plantar ligament (Lig. plantare longum) (0. T. long 

calcaneocuboid ligament). 

(fb) Deep ligaments of tarsus (Ligg. tarsi profunda). 

(fba) Plantar calcaneocuboid ligament (Lig. calcaneo- 

cuboideum plantare). 

(fbb) Plantar calcaneonavicular ligament (Lig. calcaneo- 

naviculare plantare) (0. T. inferior calcaneo- 
navicular ligament). 

(fbc) Navicular fibrocartilage (fibrocartilago navicu- 

laris). 

(fbd) Plantar navicular cuneiform ligaments (Ligg. 

navicularicuneiformia plantaria) . 

(fbe) Plantar cuboideonavicular ligament (Lig. cuboid- 

eonaviculare plantare). 



DISSECTION OF THE LOWER EXTREMITY 1 89 

(fc) Plantar intercuneiform ligaments (Ligg. intercuneiformia 

plantana). 

(fd) Plantar cuneocuboid ligament (Lig. cuneocuboideum plan- 

tare) . 

FIG. 81. 



Lig. calcaneo- 
naviculare plantare- 



Lig. nayiculari-. 
cuneiforme 



Lig. intercun. plantare 



Lig. tarsometatarseum... 




..Lig. plantare longum 



..Lig. cuboideonavic. 
plantare 



. Lig. plantare longum 
(superficial part) 



M. peronaeus long. 



Articulationes intertarseae and tarsometatarseae. Plantar view. (From Poirier et Charpy, 
Traite d'Anat. hum., Paris, 1899, 2 e<l., t. i. p. 773, Fig. 768.) 



Tarsometatarsal Articulations (Articulationes tarsometatarseae). 

(a) Articular capsules (capsulae articulares) . 

(b) Dorsal tarsometatarsal ligaments (Ligg. tarsometatarsea dorsalia). 

(c) Plantar tarsometatarsal ligaments (Ligg. tarsometatarsea plantana). 

(d) Interosseous cuneometatarsal ligaments (Ligg. cuneometatarsea inter- 

ossea). 



190 



LABORATORY MANUAL OF HUMAN ANATOMY 



Intermetatarsal Articulations (Articulationes intermetatarseae). 

(a) Articular capsules (capsulae articular es] . 

(b) Interosseous ligaments of the bases of the metatarsal bones (Ligg. 

basium [oss. metatars.] interossea). 

(c) Dorsal ligaments of the bases of the metatarsal bones (Ligg. basium 

[oss. metatars.] dorsalia). 

(d) Plantar ligaments of the bases of the metatarsal bones (Ligg. basium 

[oss. metatars.] plantaria). 

(e) Interosseous spaces of metatarsus (spatia interossea metatarsi). 

Metatarsophalangeal Articulations (Articulationes metatarsopha- 
langeae). 

(a) Articular capsules (capsulae articulares) . 

(b) Collateral ligaments (Ligg. collateralia). 

(c) Plantar accessory ligaments (Ligg. accessoria plantaria). 

(d) Transverse ligaments of the heads of the metatarsal bones (Ligg. 

capitulorum [oss. metatars.] transversa). 

FIG. 82. 

Line of articulatio talocruralis 



Line of articulatio talonavicularis 



Line of articulatio tarsometatarsea I. 




Articulatio digiti 
pedis 



Line of articulatio metatarsophalangea 

Sagittal section of the foot, passing through the great toe. (From Poirier et Charpy, Traitc 
d'Anat. hum., Paris, 1899, 2 ed., t. i. p. 787, Fig. 781.) 

Articulations of the Toes (Articulationes digitorum pedis). 

(a) Articular capsules (capsulae articulares). 

(b) Collateral ligaments (Ligg. collateralia). 

As each ligament is dissected out it may be divided and the 
joint-cavity opened. Especial attention should be paid to the 
synovial cavities of the foot. Consult your systematic anatomy 
for full descriptions. 

Review the bones of the lower extremity. 



Part III 

DISSECTION OF THE HEAD, NECK, AND DORSUM 

OF THE TRUNK, INCLUDING DISSECTION 

OF THE CENTRAL NERVOUS 

SYSTEM, EYE, AND EAR 



HEAD AND NECK 

Introductory. 

MAKE three drawings of the head (caput) and neck (collum) : 
(a) anterior view, (I)) posterior view, (c) lateral view. Distin- 
guish the portion corresponding to the skull proper (cranium) 
from the face (fades). Indicate the highest point of the head 
(vertex), separating the anterior part of the head (sinciput) 
from the posterior part (occiput). Note that the occiput is 
covered with hair; the sinciput also with the exception of its 
anterior inferior portion, the forehead (frons). Laterally, the 
temples (tempora) are naked in front but covered with hair 
behind. The external ears (auriculae) are attached to the 
cranium. 

In the drawings of the face (cf. Spalteholz, Fig. 513) label 
the nose (nasus) with its tip (apex nasi), back (dor sum nasi), 
and wings (alae nasi). Note the openings into the nose (nares) 
and the partition between (septum nasi). In the region of the 
mouth (regio oralis), draw the upper and lower lips (labia 
superius et inferius) which bound the mouth-slit (rima oris). 
Indicate exactly the furrow (sulcus nasolabialis) running down- 
ward from each ala nasi and separating the region of the mouth 
from that of the cheek (bucca) ; also, the curved transverse fur- 
row (sulcus mentolabialis) separating the region of the mouth 
from the chin (mentum). Fill in with care the details in the eye- 
regions (regiones orbitales), bounded above at the junction with 
the frons by the eyebrow (supercilium) and below at the junction 
with the bucca by the infrapalpebral furrow (sulcus infrapalpe- 
bralis). Label the upper and lower eyelids (palpebrae superior 
et inferior) and the slit between them (rima palpebrarum) , 
through which the anterior part of the eyeball (bulbus omli) is 
visible. 

Beneath the cheek, on each side, notice the region below the 
lower jaw (regio submaxillaris) and beneath the chin another 
area (regio submentalis}. Note the deep depression (fossa 
retromandibularis) below the ear and behind the lower jaw. Kx 
amine the four cavities of the face, the two eye-cavities 
(orbitae), the nasal cavity (cavum nasi) divided by the septum, 

13 l3 



194 LABORATORY MANUAL OF HUMAN ANATOMY 

and the mouth-cavity (cavum or is) containing the tongue (lin- 
gua) and the fauces. 

In the neck (collum), note in front the laryngeal prominence 
(prominentia laryngea) (0. T. Adam's apple, pomum Adami) ; 
beneath it, a depression (fossa jugularis) ; above the clavicles, 
the supraclavicular fossae (fossae supraclaviculares ma j ores) ; 
running obliquely upward and backward from the junction of 
the clavicle with the sternum, an elevated area (regio sterno- 
cleidomastoidea) . 

Make three outline sketches of the head and neck of your 
subject, corresponding to the positions indicated in Figs. 281 r 
282, 283 of Spalteholz's Atlas. Outline the boundaries of all the 
regions and print in neatly the names of the regions. Be sure 
that you understand the reason of the name for each region. 

What are meant by the following terms: nasion, glabella, 
inion, ophryon, maximum occipital point, bregma, lambda, aste- 
rion, stephanion, gonion? How is the cephalic index deter- 
mined? Is the head of your subject mesaticephalic or does it 
show any tendency towards dolichocephaly or brachycephaly ? 
(Cf. Cunningham's Systematic Anatomy, p. 173.) 

Examine closely the skin (cutis) and hairs (pili) of the head 
and neck, first with the naked eye and afterwards through a lens. 
Is the skin equally movable in all parts ? What are capilli, super- 
cilia, cilia, barba, tragi, and vibrissae? Make a sketch of the 
front and of the back of the head and neck, illustrating the hair 
streams (flumina pilorum) and vortices (vortices pilorum). De- 
monstrate the orifices of sweat-glands (pori sudoriferi). 

THE SCALP AND SUPERFICIAL STRUCTURES IN 
THE TEMPORAL REGION. 

Place a block under the head. Shave the scalp carefully. 
Make an incision from the root of the nose (nasion), along the 
middle line over the top of the head, to a point a little beyond the 
external occipital protuberance (inion) ; at right angles to this 
make a second incision from the tip of the mastoid process (pro- 
cessus mastoideus) of one side, over the top of the head, to a cor- 
responding point on the opposite side ; then, from a point on the 
latter incision just above the ear, make a cut downward and a 
little forward to the root of the zygoma. The incision should 
extend through the skin only, not through the superficial fascia. 
Reflect carefully the four flaps of skin, carrying the knife close 
to the corium. The dissection is difficult, owing (1) to the firm 



DISSECTION OF THE HEAD AND NK< K 195 

attachment of the fascia to the skin, (2) to the fact that the roots 
of the hairs penetrate the superficial fascia, and (3) to the fact 
that the scalp is often dried out if the cadaver has been kept for 
some time. 



Superficial Blood-vessels and Nerves. (Vide Fig. 105, p. 253.) 

In the superficial fascia dissect out the following, cleaning 
vessels and nerves thoroughly. 

In the Frontal Eegion. 

(a) Frontal artery (A frontalis) and supraorbital artery (A. supra- 

orbitalis). 

(b) Angular vein (V. angularis). 

(c) Supratrochlear nerve (N. supratrochlearis) and supraorbital nerve 

(TV. supraorbitalis) . 

FIG. 82a. 




Skin incisions for head and in-ck. 

In the Temporal Region. 

(a) Superficial temporal artery (A. temporalis superfiaahs) . 

(aa) Frontal branch (ramus frontalis). 

(ab) Parietal branch (ramus parietalis). 

(b) Superficial temporal vein (V. temporalis superficialis) . 

(c) Temporal branches of facial nerve (rami temporales N. fact 

(d) Zygomaticotemporal branch of zygomatic nerve (ramus zygomatico- 

temporalis N. zygomatici) (0. T. temporal branch of malar 

nerve). 

(e) Auriculotemporal nerve (N. auriculotemporahs). 
In the Mastoid and Occipital Regions. 

(a) Posterior auricular artery (A. auricularis posterior). 



196 LABORATORY MANUAL OF HUMAN ANATOMY 

(b) Occipital artery (A. occipitalis). 

(c) Posterior auricular vein (V. auricularis posterior). 

(d) Occipital vein (V. occipitalis). 

(e) Posterior auricular nerve (N. auricularis posterior). 

(ea) Occipital ramus (ramus occipitalis). 

(f) Posterior ramus of great auricular nerve (ramus posterior N. auric- 

ularis magni) . 

(g) Lesser occipital nerve (TV. occipitalis minor). 

(h) Great occipital nerve (TV. occipitalis major). (See Fig. 4, p. 47.) 

Muscles of the Scalp. 

Having isolated the blood-vessels and nerves, remove the rest 
of the superficial fascia bit by bit, exposing the muscles of the 
scalp; these and the aponeuroses are to be carefully cleaned. 
Take care not to injure the muscles which move the ear ; expose 
each muscle by putting it on the stretch. Write a description of 
the course and distribution of the nerves and blood-vessels ex- 
posed. Read the description given in your text-book of Sys- 
tematic Anatomy of each vessel and nerve. How do the struct- 
ures in your cadaver differ, if at all, from those described in 
the text-book! Note the extreme vascularity of the scalp. It 
is significant for the mobility and vitality of large flaps of de- 
tached scalp. 

Study the exact origin and insertion and the innervation of 
each of the following muscles : 

(a) Epicranius muscle (M. epicranius) (0. T. occipitofrontalis). 

(aa) Frontal muscle (M. frontalis). 

(ab) Occipital muscle (M. occipitalis). 

(aba) Procerus ("prolonged") muscle (If. procerus). 

Study the " aponeurotic helmet" (galea aponeu- 
rotica) (0. T. epicranial aponeurosis). 

(b) Anterior auricular muscle (M. auricularis anterior) (0. T. attrahens 

auriculam). 

(c) Superior auricular muscle (M. auricularis superior) (0. T. attolens 

auriculam). 

(d) Posterior auricular muscle (M. auricularis posterior) (0. T. retrahens 

auriculam ) . 

Approximate the origin and insertion of each muscle so as 
to understand clearly its action. 

Dangerous Area of the Scalp. 

Make an incision from four to eight centimetres long in the 
galea aponeurotica in the middle line at the vertex; at right 
angles to this make a short transverse incision. Lift the corners 
of the flaps with forceps and note the loose areolar tissue, free 



DISSECTION OF THE HEAD AND NK< K 197 

from fat, between it and the pericranium. The presence of this 
layer (1) permits of freedom of movement of scalp, (2) accounts 
for extensive effusion of blood which may follow scalp injury, 
and (3) explains wide distribution of pus or other inflammatory 
products in infections involving the tissue beneath the M. epi- 
cranius (hence the term " dangerous area of the scalp "). 

Lymphatics of the Scalp. (Cf. Toldt, Fig. 1085; also Poirier et 
Charpy, t. ii., fasc. iv., p. 1282, Fig. 630.) 

Try to find the- 

(a) Occipital lymph-glands (lymphoglandulae occipitales) . These are of 

significance in the diagnosis of syphilis, pediculosis, and other con- 
ditions. 

(b) Posterior auricular lymph-glands (lymphoglandulae auriculares pos- 

terior es). 

(c) Anterior auricular lymph-glands (lymphoglandulae auriculares an- 

teriores). 



OPENING THE CAVITY OF THE SKULL. 

Nowadays the brain is usually removed immediately after 
the cadaver is turned over to the department of anatomy, in 
order that it may be better prepared in formalin for subsequent 
study. Occasionally, however, a cadaver with the brain still 
in situ arrives in the dissecting-room; and in any case the student 
should know how to remove a brain. 

Raise the head of the cadaver by means of a wooden block. 
Make a coronal or frontal section, with a cartilage-knife, from 
the region behind the left ear, transversely over the vertex, to the 
same region behind the right ear. The cut should go through 
the galea aponeurotica down to the pericranium. Turn the front 
flap downward over the face and the hind flap downward over 
the neck. The temporal fascia and temporal muscle should be 
separated from the bone and reflected downward. Now make a 
horizontal cut with the saw along the largest horizontal cir- 
cumference of the skull ; the saw passes through the glabelln in 
front and a little above the protuberantia occipitalis cxtcrna 
behind. Saw through the outer table of the skull only. With 
hammer and chisel split the inner table along the line of the cut. 
Insert a hook into the cut in front and forcibly wrench off the 
skullcap. The outer surface of the dura mater is now exposed. 



198 



LABORATORY MANUAL OF HUMAN ANATOMY 



Dura Mater of Brain (Dura mater encephali). (Vide Figs. 83, 84.) 
Wipe the surface clean with a moist sponge. Study 



(a) Middle meningeal artery (A. meningea media). 

(b) Arachnoideal granulations (granulationes arachnoideales 

oni]) (0. T. Pacchionian granulations). 



[Pacchi- 



Place the head nearly upright and support it by blocks. 
Make two sagittal incisions through the dura mater, one on each 
side of the superior sagittal sinus, along its whole length. From 



FIG. 83. 




-skull 



_ Dura mat. encephali 

Arachnoidea encephali 
"-Pia mater encephali 

- - - Cav. subarachnoid. 



\\\x 

.\ \ A r .v .' G y rus cerebri 

\V x ' ^ 

\\\\ 

lyvA.^ X Cav. subarachnoid. 

k\ V 



The meninges. Schematic section passing through a sulcus cerebri. The pia mater encephali 
in red. (From Poirier et Charpy, Traite d'Anat. hum., Paris, 1899, t. iii., 1, p. 96, Fig. 69.) 

the middle of each incision make a cut .lateralward through the 
dura as far down as the cut margin of the skull ; reflect the flaps 
of dura forward and lateralward and backward and lateralward 
respectively. The subdural space (cavum subdurale) has now 
been opened up. Compare the inner surface of the dura mater 
with the outer. 

The arachnoid of the brain (arachnoidea encephali) is non- 
vascular and transparent. Through it the vessels of the pia 
mater of the brain (pia mater encephali) are visible. 

Superior Sagittal Sinus 

The veins on the surface of the brain can be seen running 
towards the superior sagittal sinus (sinus sagittalis superior) 
(O. T. superior longitudinal sinus). This sinus should be opened 
throughout its whole length with a sharp knife or scissors. 
Observe in it the network-like bands (0. T. chordae Willisi). 

Cut through the superior veins of the cerebrum which empty 



DISSECTION OF THE HEAD AND NECK 



199 



into the superior sagittal sinus and pull the hemisphere gently 
lateralward. The falx cerebri may now be examined. 

Falx Cerebri. 

Examine its extent. How is it formed! To what is it at- 
tached? Note that it contains three of the sinuses of the dura 
mater (sinus durae matris), as follows: 

(a) Superior sagittal sinus (sinus sagittalis superior] (vide supra). 

(b) Inferior sagittal sinus (sinus sagittalis inferior) (0. T. inferior 

longitudinal sinus). 

(c) Straight sinus (sinus rectus). 



Venous space 



FIG. 84. 

Sinus sagittalis superior 



Dura mater 
enceph. 




Falx cerebri 



Granulationes arachnoideales [Pacchioni] . 

Transverse section (magnified) passing through the falx cerebri, and showing the skull, menins-'< -. 
and cortex cerebri. (From Poirier et Charpy, Traite" d'Anat. hum., Paris, 1899, t. iii., 1, p. 143, Fig. 98.) 

Removal of Brain. 

Cut through the attachment of the falx cerebri to the basis 
cranii interna in front and pull it backward. Let the head hang 
over the end of the table; support the occipital regions of the 
brain in the left hand. The frontal lobes will fall away from the 
floor of the skull ; if the bulbi olfactorii remain adherent, sepa- 
rate them from the lamina cribrosa of the ethmoid bone with the 
handle of a scalpel; this easily tears across the Nn. olfactorii, 
which, coming through the lamina cribrosa from the nose, here 
plunge into the olfactory bulb to terminate there. Next cut 



200 



LABORATORY MANUAL OF HUMAN ANATOMY 



through each optic nerve (N. opticus) as it enters the skull near 
the foramen opticum. The internal carotid artery (A. carotis 
inter na) on each side should next be divided, and, behind and 
between the arteries of the two sides, the infundibulum. Behind 
and lateralward from each A. carotis interna, cut through the 
oculomotor nerve (N. oculomotorius). In cutting these nerves, 

FIG. 85. 




Exit and entrance of nervi cerebrales at the base of the skull. 

I, Nn. olfactorii ; II, N. opticus ; ///, N. oculomotorius ; IV, N. trochlearis ; V, N. trigeminus ; VI, 
N. abducens ; VII, N. facialis ; VIII, Nn. cochleae et vestibuli ; IX, N. glossopharyngeus ; A" N. vagus ; 
XI, N. accessorius; XII, N. hypoglossus; 1, peripheral olfactory neurones; G. s. G, ganglion semilunare 
(Gasseri). (From Barker, The Nerv. Syst., New York, 1931, Plate I., Fig. 2.) 

as well as the cerebral nerves farther back, the student is advised 
to cut close to the point where they pierce the dura mater on the 
right side and close to the brain on the left side. (Of. Spalteholz, 
Fig. 705.) The anterior extremity of the medial free margin of 
the tentorium cerebelli is now visible at its attachment to the pro- 
cessus clinoideus anterior of the ala parva of the sphenoid bone. 
Displace it slightly lateralward and find the trochlear nerve 
(N. trochlearis) ; cut through it on each side. 



DISSECTION OF THE HEAD AND NECK 201 

Turn the head of the cadaver forcibly to the left; raise the 
posterior part of the right cerebral hemisphere and expose the 
broad tentorium cerebelli. Cut through the tentorium along its 
attachment to the superior angle of the temporal bone (anynln* 
superior pyramidis) and, with the point of the knife, shove the 
tentorium backward out of the way. Now turn the head forcibly 
to the right and divide the tentorium on the left side in a similar 
manner. 

Next divide successively, from before backward 

(a) Trigeminal nerve (N. trigeminus) . 

(aa) Larger (sensory) root (portio major). 

(ab) Smaller (motor) root (portio minor}. 

(b) Abducent nerve (N. abducens). 

(c) Facial nerve (N. facialis). 

(d) Intermediate nerve (N. intermedius) (0. T. pars intermedia of Wris- 

berg). 

(e) Acoustic nerve (N. acusticus) (0. T. auditory nerve). 

(ea) Vestibular root (radix vestibularis) . 

(eb) Cochlear root (radix cochlearis}. 

(f) Glossopharyngeal nerve (N. glossopharyngeus ) . 

(g) Vagus nerve (N. vagus). 

(h) Accessory nerve (N. accessorius) (0. T. spinal accessory). 
(i) Hypoglossal nerve (N. Tiypoglossus). 

Now thrust a long, narrow, straight-bladed knife into the ver- 
tebral canal, cut the A. vertebral is on each side and the roots of 
the first cervical nerve on each side; just below this level sever 
the spinal cord, as nearly transversely as possible, with the 
knife or, better, with Pick's myelotome. 

The brain may now be easily removed from the skull, usually 
by gravity. Tie a thread around the basilar artery (A. basi- 
laris) and suspend the brain in a jar of ten per cent, formalin 
solution; in a few days it will be hardened sufficiently for study. 
The brain may be kept for a long time in formalin without 
injuring it for gross anatomical study. 

Dura Mater Encephali. 

The study of this membrane should now be resumed. Exam- 
ine its relations to the cerebral nerves and to the bones of the 
base of the skull. At the partitions formed by processes of the 
dura mater the falx cerebri has already been studied. The stu- 
dent should now examine thoroughly 

(a) Tentorium cerebelli. 

Note its form, position, and nttnclmuMits. In it run the important 



202 LABORATORY MANUAL OF HUMAN ANATOMY 

transverse sinus (sinus transversus) (0. T. lateral sinus) and the 
superior petrosal sinus (sinus petrosus superior). 

(b) Falx cerebelli. 

Note the relation of the occipital sinus to this membrane. 

(c) Diaphragma sellae. 

In connection with the dura mater at the base of the skull, the 
entrance and exit of the various cerebral nerves (Nn. cer eh rales) 
(0. T. cranial nerves) should be carefully studied. 

Sinuses of the Dura Mater. (Vide Spalteholz, Figs. 483 and 484.) 

These venous sinuses (sinus durae matris) should now be 
systematically examined. Open each throughout its length with 
a knife having a sharp point. Study them in the following order : 

(a) Transverse sinus (sinus transversus) (0. T. lateral sinus). 

Examine its course exactly and note its relations to the 
exterior of the skull. It is of very great practical impor- 
tance to the physician and surgeon, not infrequently 
becoming infected as a sequel of inflammation of the cel- 
lulae rnastoideae. 

(aa) Confluence of the sinuses (confluens sinuum) (0. T. torcular 

Herophili). 

(ab) Internal auditory veins (Vv. auditivae internae). 

(b) Occipital sinus (sinus occipitalis). 

(c) Superior sagittal sinus (sinus sagittalis superior) (0. T. superior 

longitudinal sinus). 

(d) Inferior sagittal sinus (sinus sagittalis inferior) (0. T. inferior 

longitudinal sinus). 

(e) Straight sinus (sinus rectus). 

Note that it receives the V. cerebri magna [Galeni]. 
(/) Inferior petrosal sinus (sinus petrosus inferior). 

How does it leave the skull? Into what does it empty? 
(g) Superior petrosal sinus (sinus petrosus superior), 
(h) Cavernous sinus (sinus cavernosus). 

Leave this unopened at present; it will be thoroughly studied 
subsequently. 

It receives the Vv. ophthalmicae superior et inferior and the 
sinus sphenoparietalis. 

(i) Anterior and posterior intercavernous sinuses (sinus cavernosus ante- 
rior et posterior). 

These together with the two cavernous sinuses constitute the 
circular sinus (sinus circularis). 

(j) Sphenoparietal sinus (sinus sphenoparietalis) (0. T. sinus alae 
parvae). 

Note that it receives one V. meningea media, the Vv. cerebri 
inferiores, the V. ophthalmomeningea, and frequently the V. 
diploica temporalis anterior. 

Certain veins should be studied at this juncture. 



DISSECTION OF THE HEAD AND NECK 



L'U'5 



(a) Basilar plexus (plexus basilaris) (0. T. basilar sinus) 

(b) Diploic veins (venae diploicae). (See Spalteholz, Fig. 485 ) 

(ba) Frontal diploic vein (V. diploica frontalis). 

(bb) Anterior temporal diploic vein ( V. diploica temporalis an- 

terior). 

(be) Posterior temporal diploic vein (V. diploica temporalis pos- 
terior), 
(bd) Occipital diploic vein (V. diploica occipitalis). 

(c) Emissary veins. 

(ca) Parietal emissary (emissarium parietale). 

(cb) Mastoid emissary (emissarium mastoideum). 

(cc) Condyloid emissary (emissarium condyloideum) . 

(cd) Occipital emissary (emissarium occipitale). 

Entrance of Arteries into the Cavity of the Skull. 

The student should next examine the exact position and rela- 
tions of the various arteries entering the cavum cranii. 

(a) Internal carotid artery (A. carotis interna). 

(b) Vertebral artery (.4. vertebralis). 

(c) Meningeal arteries (Aa. meningeae). (See Spalteholz, Fig. 447.) 

(ca) Middle meningeal artery (A. meningea media), from the A. 

niaxillaris interna. 

(cb) Anterior meningeal artery (A. meningea anterior), from the 

A. ethmoidalis anterior of the A. ophthalrnica. 

(cc) Accessory meningeal branch (ramus meningeus accessorius) 

(0. T. small meningeal artery), usually from the A. menin- 
gea media. It will be studied later. 

(cd) Posterior meningeal artery (A. meningea posterior), from the 

A. pharyngea ascendens. 

(ce) Meningeal branch (ramus meningeus), from the A. occipitalis. 

It is inconstant. 

(cf) Meningeal branch (ramus meningeus), from the A. verte- 

bralis. 

Hypophysis. 

Cut through the diaphragma sellae and extricate the hypo- 
physis (O. T. pituitary body) from the sella turcica. Observe its 
shape and consistency and its division into an anterior lobe 
(lobus anterior) and a posterior lobe (lobus posterior). Make 
a sagittal section through it and observe the relations of the 
two lobes to each other. With which is the infundibulum con- 
tinuous? Read up on the embryological origin of these two 
lobes. The cavity of the skull should now be packed with tow 
soaked in a solution of carbolic acid or in alcohol. Replace the 
skul lea]) and stitch the scalp flaps in position over it. This is 
very important for the further dissection. 



204 LABORATORY JMANUAL OF HUMAN ANATOMY 

SIDE OF NECK. 

Examination of Surface. 

Review the names of the regions of the neck. In the middle 
line feel the hyoid bone ; run the finger along its body and make 
out the greater cornua. A finger-breadth lower the thyreoid 
cartilage is reached. Examine it in detail. Lower still, palpate 
the cricoid cartilage, the cricothyreoid space, and the trachea. 
Can you make out the thyreoid gland? Ascertain the vertebral 
levels of the hyoid bone, the cricoid cartilage, and the upper 
border of the manubrium. 

Make deep pressure in upper part of supraclavicular fossa 
and feel transverse process of seventh cervical vertebra. Is 
there a cervical rib present! Make also deep pressure over the 
line of the carotid vessels at the level of the cricoid cartilage and 
feel the prominent anterior tubercle of the transverse process of 
the sixth cervical vertebra. This is the so-called ' ' carotid tuber 
cle" (Chassaignac's), an important landmark to the surgeon, 
since the A. carotis lies directly anterior to it. 

Palpate through the skin the anterior margin of the M. trape- 
zius, the clavicle, the upper border of the manubrium, the lower 
margin of the mandible, and the mastoid process. Note the 
exact position of the M. sternocleidomastoideus, separating the 
anterior from the posterior triangle of the neck. Above the 
manubrium note the jugular fossa (fossa jugular is), sometimes 
called the " suprasternal fossa" or " fonticulus gutturis"; it 
is especially marked in marasmus. 

Skin, Superficial Fascia, and Platysma. 

The skin is thin and rather loose. Place a large block beneath 
the shoulders and put the parts upon the stretch. Make three 
incisions (see Fig. 82a, p. 195) : (1) in the linea mediana ante- 
rior from the chin to the manubrium; (2) from the middle of 
the upper margin of the manubrium lateralward along the clavi- 
cle to the acromion; (3) from the processus mastoideus obliquely 
downward and medialward along the anterior margin of the 
M. sternocleidomastoideus to the angle formed by incisions (1) 
and (2). Reflect the anterior triangular flap upward and the 
posterior one backward. 

In the superficial fascia, compare the amount of fat present 
in your subject with that in the cadaver of the opposite sex. 
Note the relative abundance of fat between the chin and the 
hyoid bone. To what is " double chin" due? Take care to avoid 



DISSECTION OF THE HEAD AND NK< K 



205 



FIG. 86. 



Lymphpglandulae 
occipitales 



Lymphoglandula auricularis 
posterior 



Lymphoglandulae cervicales 
superfieiales 




The superficial Ivmphatic vessels and lymph-glands of thi- head, neck, upp-r th,>n,<-ic and 
shoulder regions. (After Toldt. Aunt. Atlas, Wirn, 1900, 2 Aufl., p. 702, Fig. 1 



206 



LABORATORY MANUAL OF HUMAN ANATOMY 



Vv. temporales superflcial 



V. temporalis media 



FIG. 87. 

Vv. palpebrales superiores Vv. palpebrales inferiores 

V. frontalis 

V. nasofrontalis 
J^k Vv. nasales extcrnae 
V. angularis 

V. transversa 1'aciei 

V. labialis superior 

Venous plexus about 
the ductus paroticleus 

V. anastomica faeialis 
'' V. labialis inferior 
' Vv. parotideae 

anteriores 
V. faeialis anterior 
Vv. masseterk-au 

A. maxillaris 
externa 



. submentalis 
Glandula sv.bmasilht ris 




Vv. auriculares anteriores*'' 

V. occipitalis ' 
V. auricularis posterior 

V. faeialis posterior -' 

V. faeialis communis 
Fascia colli (lamina superficialis laid back) 

.Fascia praevertebralis 
V. cervicalis subcutanea 
V. cervicalis superficialis 
V. transversa scapulae. 
Lower belly of the M. omohyoideus " v 
( enclosed in the deep layer of the- 

cervical fascia) 
Fascia coracodavicularis 
V. acromialis 



V. jugularis externa 



V. jugularis 
anterior 



Rete acromiale 



'Fascia pectoralis (lamina profunda ) 
Kami pectorales of the A. and V. thoracoacromialis 
I 'Vv. deltoideae 

V. cephalica 



The superficial veins of the head and neck. ( After Toldt, Anat. 
Atlas, Wien, 1900, 2 Aufl., p. 664, Fig. 1046.) 



DISSECTION OF THE HEAD AND NECK 207 

injury to the platysma, which lies in the superficial fascia. 
Observe the superior rami of the cutaneous nerve of the front 
of the neck (rami superiores N. cutanei colli), superficial to the 
platysma. The superficial lymphatic channels can be well seen 
only in especially injected specimens. (Vide Fig. 86.) 

Study the form, position, origin, insertion, innervation, and 
action of the platysma. Is the muscle in general placed super- 
ficial or deep as regards the panniculus adiposus ? Is the fat of 
double chin premuscular, retromuscular, or both ? Note that the 
platysma always moves with the skin of the neck. The loose 
areolar tissue between the platysma and the superficial layer of 
the fascia colli permits of free movement. What is the relation 
of the anterior jugular and of the external vein to the platysma? 
Why is the platysma called the muscle of fright? (Cf. Duchenne, 
Mecanisme de la physionomie humaine, Figs. 61, 62, and 63.) 
Why is it easier to pinch up a fold of skin vertically than trans- 
versely in the neck! What effect would the platysma have on 
the edges of a wound passing through the skin and muscles at 
right angles to the course of its fibres? 

Structures between the Platysma and the Surface of the Fascia Colli. 
Reflect the platysma from below upward, taking care not to 
injure the subjacent nerves and veins. 

Veins. 
External jugular (V. jugularis externa). 

(a) Posterior auricular (V. auricularis posterior). 

(b) Anterior jugular (V. jugularis anterior}. 

How would you draw a line on the surface of the neck correspond- 
ing to the position of the external jugular vein? Observe the super- 
ficial lymphatic glands (lympJioglandulae cervicales superficiales) 
along the external jugular vein. How many are there? Whence do 
they draw lymph? (Vide Figs. 86 and 93.) 

Nerves. 

Branches of the cervical plexus. 

(a) Lesser occipital nerve (N. occipitalis minor). 

(b) Great auricular nerve (N. auricularis magnus). 

(c) Cutaneous nerve of the front of the neck (N. cutaneus colli) (0. 

T. superficial cervical). 

(ca) Upper rami (rami superiores). 

(cb) Lower rami (rami inferiores). 

Is a cutaneous nerve of the back of the neck 
cutaneus cervicis) present? 

(d) Supraclavicular nerves (Nn. supraclaviculares) . 

(da) Anterior (Nn. supraclaviculares anteriores) (0. T. supn 
sternal). 



208 



LABORATORY MANUAL OF HUMAN ANATOMY 



FIG. 87a. 



N. auricu- 
laris 



Ramus anterior. 



Vena jugularis _ 
anterior 



Rami anastornotici 

Ute' of the N. facialis 




magnus ( Ramus posterior.^ 



Ramus superior of 
the N. cutaneus colli 



Ramus colli of the 
N. facialis (for the "* 
platysma) 



Rami superiores of 
the N. cutaneus colli 
Connecting branch 
to the N. facialis -1 



Ramus inferior of 
the N. cutaneus ~"~ 
colli 



--. Vena jugularis 

externa 

*> if. occipitalis minor 
N. cutaneus cervicis (Var.) 
Ramus externus of 
the N. accessorius 

Trunk of the Nn. 
~- supraclaviculares 
Nll. supraclavicu- 
lares posteriores 



Nn. supraclaviculares /' ,* 

anteriores Platysma "/ f: S 

If 
Nn. supraclaviculares medii 



The cutaneous branches from the cervical plexus to the head and neck and their relation to the 
platysma. The bundles of the latter have been pulled apart in places to show partially the nerves 
under it. ( After Toldt, Anat. Atlas, \Vien, 1903, p. 819, Fig. 1251. ) 



DISSECTION OF THE HEAD AND NK< K 209 

(db) Middle (Nn. supraclaviculares medii) (0. T. supra- 
clavicular). 

Note that the direction of the six principal branches corresponds 
to six lines radiating from a point at the middle of the posterior 
border of the M. sternocleidomastoideus. 
Branches of facial nerve to neck. 

(a) Branch to front of neck (ramus colli N. facialis). 

Note its anastomosis with a branch of the N. cutaneus colli. 

Deep Cervical Fascia and Aponeuroses. (Figs. 87, 88, and 89.) 

At this stage, before proceeding further with the dissection, 
the student will do well to read a good description of the deep 
cervical fascia. One of the best descriptions is that in Poirier et 
Charpy, t. ii. pp. 409-430. If the student does not read French 
easily, he will find a brief description in Cunningham's Text- 
Book of Anatomy, 1902, pp. 373, 374, 1178, 1179. In the descrip- 
tion, pay attention especially to the following points and verify 
each as the dissection goes on : 

General subdivision of the deep fascia and aponeuroses of the front of 
the neck into 

(a) A superficial part (fascia colli, superficial layer), corresponding 

to the sternocleidomastoid muscles. 

(b) A middle part (fascia colli, deep layer) (0. T. pretracheal fascia), 

corresponding to the subhyoid muscles. 

(c) A deep part (fascia praevertebralis) , corresponding to the prever- 

tebral muscles. 

Between (b) and (c) are a large central compartment containing 
viscera and a small lateral compartment on each side containing the 
great vessels, each compartment having a sheath. 

The Superficial Part (Fascia colli, superficial layer). 
Attachments. 

Above, to prominentia occipitalis externa, linea nuchae superior, 
processus mastoideus, and to the fascia parotideomasseterica and 
the inferior border of the mandibula. 
Below, to the spina scapulae, anterior border of clavicle, upper border 

of sternum. 

Behind, to the ligamentum nuchae. 
In front, to same layer of opposite side. 

Note splitting of layer to enclose sternocleidomastoid muscle 
(M. sternocleidomastoideus) and again to enclose the trapezius 
muscle (M. trapezius) ; it does not split above the sternum to 
make suprasternal compartments, as ordinarily described. 

Observe firm transverse fixation of superficial layer of fascia 
colli to anterior surface of hyoid bone. This is the true line of 
demarcation between the head and the neck; the suprahyoid 
muscles are all innervated by cerebral nerves. The mtermuscu- 

14 



210 



LABORATORY MANUAL OF HUMAN ANATOMY 



lar septa separating the muscles of the front of the neck (collum) 
from those of the back of the neck (cervix) are attached to the 
deep surface of the layer under description; they pass medial- 
ward and a little forward, and become attached to the lateral 
portion of the fascia praevertebralis which encloses the scalene 

FIG. 88. 



K 



Fascia parotideomasseterica' 



Platysma 



M. sternocleidomastoideus ^j 



Lamina profunda fasciae colli 



Regio colli anterior 



M. sterno- 
cleidomastoideus ^8P 



Lamina profunda ~^H 

ll ^jffl. ,JJH 




Lamina profunda 
fasciae colli 



Platysma - 



The fascia colli on the right side after the removal of the platysma. The superficial lamina is 
partly taken away in places where it is sharply separated from the deep lamina. The middle portion 
of the sternocleidomastoid muscle has been removed to show the deep layer of the fascia colli, under 
which is seen the upper belly of the omohyoid muscle shining through. (After Toldt, Anat. Atlas, 
Wien, 1900, 2 Aufl., p. 287, Fig. 525.) 

muscles (Mm. scaleni) and extends between the anterior and 
posterior tubercles of the transverse processes of the cervical 
vertebrae. 

Note that where the superficial layer of the fascia colli is 
covered by the platysma it is thinner than elsewhere. Examine 
closely various parts of the fascia under description : 



DISSECTION OF THE HEAD AND NK< K 



I'll 



1. Sternomastoid portion. 

2. Parotid portion. 

3. Submaxillary portion. 

4. Median suprahyoid portion. 

5. Median infrahyoid portion. 

6. Supraclavicular portion. 

The Middle Part (Fascia colli, deep layer] ("omoclavicular aponeurosis" 

of Richet). 
Extent. 

Vertically, from os hyoideum to thorax. 
Laterally, from one M. omohyoideus to the other. 

FIG. 89. 



Sheath of the. 

scalene 

muscles 
Adipose mass 



Space behind 

the fascia 

praeverte- 

bralis 

I'rrviseeral --' 
space 



Superficial sub- 
aponeurotic space 




...Visceral sheath 



The interaponeurotic spaces, seen in section and supposed to be injected. The visceral and vascular 
sheaths, the sagittal septa, and the fascia praevertebralis are represented by dotted lines, the middle 
aponeurosis by a heavy black line. The section passes immediately below the larynx. (From Poirier 
ct Charpy, Traits d'Anat. hum., Paris, 1901, 2 ed., t. ii. p. 426, Fig. 269.) 

Embedded in it are the omohyoid, sternohyoid, cleidohyoid, 
and thyreohyoid muscles. In lower forms this fascia is repre- 
sented by a single broad cleidohyoid muscle; in man it has 
become differentiated into several muscles with connective tissue 
between. (Gegenbaur.) 



212 LABORATORY MANUAL OF HUMAN ANATOMY 

Distinguish in it 

(1) A deep or intermuscular layer. 

(2) A superficial or premuscular layer. 

The suprasternal space (sometimes called Burns' space) is 
situated between the superficial layer of the fascia colli and the 
premuscular layer of the middle layer of the fascia colli. 
(Charpy.) Examine its contents. The interaponeurotic veins 
near the base of the neck are aspirated during inspiration. 
Hence this is the most dangerous area for the entrance of air 
into the veins during surgical operations. 

The Deep Part (Fascia praevertebralis). 
Note its two parts : 

(1) That extending from the anterior longitudinal ligament of the 
spine to the anterior tubercles of the transverse processes; it covers 
the pre vertebral muscles proper (Mm. longi colli et capitis). Observe 
the relation of the N. sympathicus to this part. 

(2) That extending from the anterior to the posterior tubercles 
around the Mm. scaleni. Observe the relation of the N. phrenicus 
and of the Nn. cervicales to this part. 

The fascia praevertebralis is part of the great common sheath 
of the body-cavity, being for the neck what the endothoracic 
fascia, the transversalis fascia, and the pelvic fascia are for the 
other visceral cavities. (Fawcett.) 

The Visceral Sheath. 

Contents. Thyreoid gland, trachea, oesophagus, and pharynx. 

Shape. In cross-section, semicylindrical. 

Attachments. 

Behind, by lateral angles to the vertebral column; between these two 
attachments is left a retrovisceral or prevertebral space. This is 
of especial interest in the retropharyngeal region (postpharyngeal 
abscess, etc.). 
Above, to base of skull. 
Below, extends into mediastinum. 

The Vascular Sheath. 

(a) Common sheath. (Note relation of ramus descendens N. hypo- 

glossi.) Observe attachment lateralward to deep layer of fascia 
colli and medialward to visceral sheath. The common sheath 
encloses b, c } and d. 

(b) Sheath for A. carotis (loose, to permit of pulsation). 

(c) Sheath for V. jugularis interna (dense, especially between artery 

and vein, septum vasorum). 

(d) Sheath for N. vagus (always satellite of artery, even in embryonic 

life, when vein is distant). 



DISSECTION OF THE 11KAI) AND NK( K 213 

Some Enclosed Spaces of the Neck. 

(a) Subcutaneous space between fascia superliruilis ;m<l superficial 

layer of fascia colli. 

(b) Superficial subaponeurotic space between superficial and deep 

layers of fascia colli. 

(c) Suprasternal space. 

(d) Previsceral space between the deep layer of the fascia colli in 

front and the visceral and vascular sheaths behind. It contains 
fat and deep lymphatic glands. 

(e) Retrovisceral or prevertebral space bounded in front by visceral 

sheath, behind by spine, and laterally by attachments of visceral 
sheath to spine. 

Surgical Anatomical Points. 

(a) Abscesses within the visceral sheath either are secondary to infections 

involving the organs contained within it or are due to primary pyo- 
genie infection of the areolar tissue inside it. 

(b) Abscesses secondary to disease of the retropharyngeal lymph-glands 

lie in front of the fascia praevertebralis in the space between it 
and the visceral sheath. 

(c) Abscesses secondary to disease of the cervical vertebrae lie behind 

the fascia praevertebralis and spread lateralward behind the vas- 
cular sheath; they usually point behind the M. sternocleidomns- 
toideus, and may be opened by an incision at the posterior border 
of this muscle. 

(d) The carotid chain of lymph-glands (lymphoglandulae cervicales pro- 

fundae) lies inside the common part of the vascular sheath. Ab- 
scess resulting from disease of these glands usually points upon 
the surface, owing to the formation of adhesions: first between the 
gland and the vascular sheath, then between the latter and the 
superficial layer of the fascia colli, and finally between the latter 
and the skin. 

Sternocleidomastoid Muscle (M. sternocleidomastoideus). (Vide 

Fig. 91, p. 219.) 

Note that it divides the neck into an anterior and a posterior 
triangle. Remove from its surface the covering derived from 
the superficial layer of the fascia colli. Ascertain exactly its 
origin, insertion, innervation, and action. Why does Krausr 
designate it " the quadrigeminal muscle of the head" Which 
of the four parts (sternomastoid, sterno-occipital, cleidomastdid, 
and cleido-occipital) are present in your cadaver? 

Posterior Triangle of the Neck. (Vide Fig. 91, p. 219.) 

Remove, over the posterior triangle, the superficial and deep 
layers of the fascia colli; note that the former covers the whol< 
triangle, the latter only its inferior part as far as the upper 



214 LABORATORY MANUAL OF HUMAN ANATOMY 

border of the inferior belly (venter inferior) of the M. omo- 
hyoideus. Beneath the tendinous part of the M. omohyoideus, 
where it passes below the sternomastoid, secure the small nerve- 
twig from the descending ramus of the hypoglossal nerve (R. de- 
scendens N. hypoglossi) which goes to it. How is the posterior 
triangle bounded in front, behind, and below? How is its apex 
formed? The inferior belly of the omohyoid muscle divides it 
into (a) an upper, larger part, the occipital triangle, and (6) a 
lower, very much smaller part, the supraclavicular triangle. 
Notice the chain of lymph-glands at the posterior border of the 
M. sternocleidomastoideus. They are often inflamed in diseases 
of the scalp (impetigo pedicularis) . 

The Occipital Triangle. 

What are its boundaries f How is its floor formed from above 
downward? Observe among its contents the following : 

Arteries. (Vide Fig. 97, p. 236.) 

(a) Occipital artery (A. occipitalis) occasionally. 

(b) Transverse artery of neck (A. transversa colli}. 
Veins. 

(a) Occipital vein (V. occipitalis}. 

(b) Transverse vein of neck (V. transversa colli). 
Nerves. 

(a) Supraclavicular branches of the cervical plexus (Nn. supraclavicu- 

lar -es). 

(b) Accessory nerve (N. accessorius) (0. T. spinal accessory). 

(c) Branches of cervical nerves to M. trapezius and to M. levator scap- 

ulae (rami muscular es Nn. cervicalium) . 

Many of these structures will be studied more particularly 
when the body is turned on its face and the back of the neck is 
dissected. 

The Supraclavicular Triangle (O. T. Subclavian Triangle). 

The fascia praevertebralis may be removed where it covers 
the vessels and nerves. Note its continuity with the axillary 
sheath. What are the boundaries of the supraclavicular tri- 
angle! Find and study the following structures, and compare 
each as found in the cadaver with the description in your text- 
book of systematic anatomy. 

Arteries. (Vide Fig. 16, p. 63.) 

(a) Third portion of subclavian artery (A. subclavia). 

(b) Transverse artery of neck (A. transversa colli). 

(c) Transverse artery of scapula ( A. transversa scapulae) (0. T. supra- 

scapular). 



DISSECTION OF THE HEAD AND NECK 



215 



Veins. (Vide Fig. 87, p. 206.) 

(a) External jugular vein (V. jugularis externa). 

(b) Transverse vein of scapula (V. transversa scapulae) (0. T. supra- 

scapular). 

(c) Transverse vein of neck (V. transversa colli). 

(d) Subclavian vein (V. subclavia). 




ci 

Plexus cervicobrachialis. (After P. Eisler, from Rauber's Text-Book.) Ventral view. 
h, N. hypoglossus; dh, ramus descendens N. hypoglossi, which, along with dc, the ramus de- 
scendens cervicalis, forms the ansa hypoglossi ; am, N. occipitalis minor ; au, N. auricularis magnus ; 
sec, N. cutaneus colli ; a, to N. accessorius ; spc, Nn. supraclaviculares ; p, N. phrenicus ; ds, N. dorealis 
scapulae; sps, N. suprascapularis ; ss, Nn. subscapulares ; sc, N. subclavius; ax, N. axillaris; co, N. 
to M. coracobrachialis ; R, N. radialis ; me, N. musculocutaneus ; if, N. medianus ; to, Nn. tboracalea 
anteriores ; ff, N. thoracalis longus ; U, N. ulnaris ; cm, N. cutaneus antibrachii medialis ; ci, N. cutaneus 
brachii medialis ; ih, N. intercostobrachialis. (From Barker, The Nervous System, New York, 1899, p. 
324, Fig. 186.) 

Nerves. (To be studied in conjunction with the dissector of the upper 

extremity. ) 
(a) Brachial plexus (plexus brachialis). (Vide Fig. 90.) 



216 LABORATORY MANUAL OF HUMAN ANATOMY 

(aa) Supraclavicular part (pars supraclavicularis ) . 

(aaa) Posterior thoracic nerves (Nn. thoracales poste- 

rior es). 

(1) Dorsal nerve of scapula (N. dorsalis scap- 

ulae) (0. T. nerve to the rhomboids). 

(2) Long thoracic nerve (N. thoracalis longus) 

(0. T. external respiratory nerve of Bell, 
or posterior thoracic). 

(aab) Anterior thoracic nerves (Nn. thoracales ante- 

rior es}. 

(aac) Subclavius nerve (N. subclavius). 

(aad) Suprascapular nerve (N. suprascapularis) . 

(aae) Subscapular nerves (Nn. subscapulares) . 

(aa/) Thoracodorsal nerve (N. thoracodorsalis) (0. T. 

long subscapular nerve). 

(aag) Axillary nerve (N. axillaris) (0. T. circumflex 
nerve). 

(1) Muscular branches (rami musculares) . 

(2) Lateral cutaneous nerve of arm (N. cuta- 

neus brachii lateralis). 

Surgical Anatomical Points. 

Note that the supraclavicular triangle is the " seat of election" for liga- 
ture of the subclavian artery; its relations to neighboring structures are, 
therefore, exceedingly important. Examine these carefully, using your 
text-book as a guide. Note especially the relation of the artery to the 
external jugular vein and its tributaries. Run the finger down the lateral 
margin of the M. scalenus anterior (just beneath the posterior margin of 
the M. sternocleidomastoideus) until the scalene tubercle (tuberculum 
scaleni) on the first rib is reached. This is the guiding-point for the 
surgeon in the operation of ligation. If the finger-nail rest on the tuber- 
culum scaleni, the artery will be felt, in the living subject, to pulsate 
against the finger-pulp. The proximity of the lowest trunk of the plexus, 
brachialis and of the cupula pleurae to the artery are important points- 
to the surgeon. If a cervical rib be present, the artery may either be in 
front of it or arch above it. 

The V. jugularis externa is often opened in the posterior triangle to 
relieve the right heart in asphyxia; its position corresponds to a line 
drawn from the angle of the jaw to the middle of the clavicle. It should 
not be opened in the lower part of its course, where it is held open by the 
fascia, owing to the danger of suction of air into the vessel during inspi- 
ration. 

How is the floor of the supraclavicular triangle formed? 

Anterior Triangle of the Neck. (Vide Figs. 87 and 91.) 

Turn the N. cutaneus colli and the ramus colli N. facial is 
backward and remove the superficial and deep layers of the 
fascia colli. Note that the deep layer does not extend above 
the omohyoid muscle or the hyoid bone. How is the anterior 



DISSECTION OF THE HEAD AND NK< K 

triangle of the neck bounded? Locate (a) superior belly of 01110- 
liyoid muscle (venter superior M. omohyoidei), (b) digastric 
muscle (M. digastricus), and (c) stylohyoid muscle (M. stylo- 
liyoideus). Clean their surfaces, but avoid injury to (1) the 
branches of the ramus descendens N. hypoglossi entering the 
upper border of the venter superior M. omohyoidei, (2) the 
anterior and posterior facial veins (Vv. faciales anterior et pos- 
terior) where they unite to form the common facial vein (V. 
facialis communis) on the posterior belly of the M. digastricus, 
and (3) the mylohyoid nerve (N. mylohyoideus) entering the 
upper border of the venter anterior of the M. digastricus. When 
these muscles have been thoroughly cleaned, it will be noticed 
that they divide the anterior triangle of the neck into three sub- 
sidiary triangles from above downward : 

(a) Submaxillary or digastric triangle. 

(b) Carotid triangle (sometimes called "superior carotid" triangle). 

(c) Muscular triangle (sometimes called "inferior carotid" triangle). 

Review the boundaries of these three triangles. Note espe- 
cially that the muscular triangle is covered by both the super- 
ficial and deep layers of the fascia colli, the digastric and carotid 
triangles by the superficial layer only. 

The anterior triangle should be dissected as a whole, rather 
than the subsidiary triangles one by one ; the structures passing 
through more than one triangle are then studied in their con- 
tinuity. The areolar tissue binding arteries, veins, nerves, and 
muscles together is to be removed bit by bit. Atlases should be 
open before the student constantly; as soon as a structure 
exposed, it should be identified by reference to the plates in the 
atlases and the name repeatedly associated with it as it is further 
handled. From time to time, a description of all structure! 
exposed should be read in the systematic text-book. It i 
helpful to write down in full each new term met with m order 1 
learn it more quickly and surely. It will be found 
majority of the structures can be exposed without 
through any muscle or larger vessel or nerve. 

Submaxillary or Digastric Triangle. (Vide Fig. 113, P- 266.) 

It is arbitrarily subdivided into an anterior and a posterior 

portion by the stylomandibular ligament (ligamentum stylon^n 

dibulare) (0. T. stylomaxillary ligament) (cf. Spalteholz, v 

Fig. 206) and a line drawn downward from it. 
In the anterior portion find 



218 LABORATORY MANUAL OF HUMAN ANATOMY 

(a) Lymph-glands. 

(aa) Submaxillary lymph-glands (lymphoglandulae submaxil- 

lares). There are three, anterior, middle, and posterior. 

(ab) Submental lymph-glands (between the anterior bellies of Mm. 

digastrici of the two sides). 

In cancer of the lip which glands are likely to be the 
seat of metastatic growth? 

(b) Submaxillary salivary gland (glandula submaxillaris) . 

Study also the following : 

Arteries. 

(a) External maxillary artery (A. maxillaris externa) (0. T. facial 

artery). 

(aa) Ascending palatine (A. palatina ascendens). 

(ab) Tonsillar ramus (ramus tonsillaris). 

(ac) Submental (A. submentalis). 

(ad) Glandular rami (rami glandular es) . 

(b) Mylohyoid ramus of internal maxillary artery (ramus mylohyoideus 

A. maxillaris internae). 

(c) Lingual artery (A. lingualis). This is really not in the triangle, 

being beneath its floor, as it is completely covered by the M. 
hyoglossus. It is very important to study it, however, in this 
situation, as it is the point where it is ligated. Notice that it lies 
in a minute triangle (Lessees triangle), formed by the margin 
of the M. mylohyoideus, the venter posterior M. digastrici, and 
the N. hypoglossus. If the M. hyoglossus be exposed within this 
little triangle and the muscle split vertically, the lingual artery is 
exposed. (Fig. 113.) 

Veins. (Vide Fig. 87, p. 206.) 

(a) Anterior facial vein (V. facialis anterior) and tributaries. 

(aa) Submental vein (V. submentalis). 

(ab) Palatine vein (V. palatina). 

(b) Tributaries of internal jugular vein (V. jugularis interna). 

(ba) Lingual vein (V. lingualis). 

(bb) Vein accompanying hypoglossal nerve (V. comitans N. 

hypoglossi). 
Nerves. 

(a) Hypoglossal nerve (N. hypoglossus). 

(b) Mylohyoid nerve (N. mylohyoideus) from the third division of 

the fifth cerebral nerve. 

In the posterior portion of the triangle find 

(a) Lower part of parotid gland (glandula parotis). 

(b) External carotid artery (A. carotis externa). 

(ba) Posterior auricular artery (A. auricularis posterior). 

Carotid Triangle. (Vide Fig. 91.) 

Why is it so called! Find in it and study the following 
structures : 



DISSECTION OF THE HEAD AND NECK 



219 



FIG. 91. 



Ramus frontalis 



Ramus 
parietal is 

A. zygo- 
matico- 
orbitalis -, 
Kami 
auriculares-^ 

anteriores 

A. temporalis 

superficialis 

Raraus occipi- 
talis of the A. 
auricularis 

posterior 

Glandida parotis 

A. occipitalis i 
A. sternocleidomastoidea 

Ramus stern ocleidomastoideus of the 
A. thyreoidea superior 

A. cervicalis superficialis 



A. frontalis 

A. dorsal is nasi from the A. 
/ ophthalmica 



\. angularis 



A. carotis communis 
. Jf. omohyoideus 




A. labialis superior 
superficial branch ) 

A. transversa faciei 



A. submentalis 
Lymphoglandulae 

submaxillares 
Glandida submaxittaris 

A. maxillaris externa 



Ramus hyoideus 
A. lingualis 
A. laryngea superior 
A. thyreoidea superior 

A. carotis intema 



Ramus perforans 

of the A. mam- 

maria interna 



A. thoracoacromialis { 



Ramus deltoideus 
Ramus acromialis : 



Fascia rorarwlaricnlaris 



The superficial arteries of the head, neck, upper mammary and shoulder regions, seen from the 
right side. The fascia parotideomasseterica has been retained over the anterior part of the parotid 
gland. The lower end of the M. quadratus labii superioris has been removed. (After Toldt, Anat. 
Atlas, Wien, 1900, 2 Aufl., p. 592, Fig. 967.) 



220 LABORATORY MANUAL OF HUMAN ANATOMY 

Arteries. 

(a) Common carotid artery (A. carotis communis). 

(aa) External carotid artery (A. carotis externa). 

(aaa) Superior thyreoid (A. thyreoidea superior). 

(1) Hyoid ramus (ramus hyoideus). 

(2) Sternomastoid ramus (ramus sternomas- 

toideus). 

(3) Superior laryngeal artery (4- laryngea 

superior). 

(aab) Lingual artery (A. lingualis). 

(1) Hyoid ramus (ramus hyoideus). 

(aac) External maxillary artery (A. maxillaris externa) 

(0. T. facial).. 

(aad) Sternocleidomastoid artery (A. sternocleidomas- 

toidea). 

(aae) Occipital artery (A. occipitalis). 

(aaf) Ascending pharyngeal artery (A. pharyngea as- 



(ab) Internal carotid artery (A. carotis interna). 
Veins. 

(a) Internal jugular vein (V. jugularis interna). 

(aa) Lingual vein (V. lingualis). 

(ab) Superior thyreoid veins (Vv. thyreoideae superior -es) . 

(aba) Sternocleidomastoid vein (V. sternocleidomas- 

toidea). 

(abb) Superior laryngeal vein (V. laryngea superior). 

(ac) Common facial vein (V. facialis communis). 

(aca) Anterior facial vein (V. facialis anterior). 

(acb) Posterior facial vein (V. facialis posterior). 
Nerves. Many of these will be much better seen later; at present they 

should simply be located in the triangle. 

(a) Hypoglossal nerve (N. hypoglossus). 

(aa) Descending ramus (ramus descendens). 

(ab) Loop of the hypoglossus (ansa hypoglossi). 

(ac) Thyreohyoid ramus (ramus thyreohyoideus) . 

(b) Accessory nerve (N. accessorius) (0. T. spinal accessory). 

(ba) Internal ramus (ramus internus). 

(bb) External ramus (ramus externus). 

(c) Vagus nerve (N. vagus) (0. T. pneumogastric nerve). 

(ca) Superior laryngeal nerve (N. laryngeus superior). 

(caa) External ramus (ramus externus) (0. T. external 

laryngeal nerve), 
(cafe) Internal ramus (ramus internus) (0. T. internal 

laryngeal nerve). 

(d) Glossopharyngeal nerve (N. glossopharyngeus) . 

(e) Sympathetic trunk (truncus sympathicus [pars cervicalis]). 

(ea) Superior cervical ganglion (ganglion cervicale superius). 

(eb) External carotid nerves (Nn. carotid externi). 

(ec) External carotid plexus (plexus caroticus externus). 

(ed) Superior thyreoid plexus (plexus thyreoideus superior). 

(ee) Lingual plexus (plexus lingualis). 

(ef) External maxillary plexus (plexus maxillaris externus). 



DISSECTION OF THE HEAD AND NECK 



221 



FIG. 92. 



M. digastricus 
M. mylohyoideus 
M. stijU>phnr<iii(jeus 
N. glossopharyngeus 

N. accessorius 

N. hypoglossus 



Ganglion .J 
nodosuui 



N. laryngeus superior 



Ganglion cervicale 
superius 

Ramus extern us of - 

the N. laryngeus 

superior 

N. vagus (cervical part) 

Truncus sympathicus- 

Ganglion cervical 
inferius 

Ansa subclayia 
(Vieussenii) ~~ 



Branching off of . 
the N. recurrens 

Ramus cardiacus _ 
inferior of the 

N. vagus 
Rami tracheales et 

oesophagei 
N. vagus ( thoracic 
part) 



Ramus 

bronchial is 

anterior 



Nn. cardiaci. 

superior and 

inferior united 



Ploxus pulmonalis anterior 
Ramus dexter of the A. pulmonalis 

Vr. i>iiliin>nalc$ dejctrae 



A. carotin iiitrriia 
Foramen jugulare 



- N. accessorius 
(ramus extern us) 



Rami pharyngei 
'- Ramus thyreohyoideus 
_ N. laryngeus superior 

__ N. vagus (cervical part) 



M. aternocleidomastoideug 
(laid back) 

Plexus cervicalis 



N. phrenicus 

A. carotis communis 



_ _. Ramus cardiacus superior 
of the N. vagus 



~ Plexus brachialis 
- A 



Bmnc-hing off 

of tin- 
N. recurrens 




A. pulmonalis 
Plexus canliacus 



NX - V. cava superior 



The anterior region of the neck. The head is strongly pull'l back. (After Toldt, Anat. Atlas, 
Wien, 1903, 3 Aufl., p. 878, Fig. 1321.) 



222 LABORATORY MANUAL OF HUMAN ANATOMY 

Lymph-glands. (Vide Fig. 93.) 

(a) Superior deep cervical lymph-glands (lymphoglandulae cervicales 

profundae superiores). 
Viscera. 

(a) Larynx. 

(b) Pharynx. 

(c) Carotid skein (glomus caroticum) (0. T. intercarotid gland). 

Observe that some of the structures above enumerated become 
visible only after the parts have been loosened by dissection, 
that the greater cornu of the os hyoideum is in this space, and 
that, while the N. hypoglossus runs transversely in the spaces, 
the N. vagus and truncus sympathicus run vertically and the 
other large nerves obliquely. 

Muscular Triangle. 

Why is it so called ? Find and study the following structures : 

Muscles. 

(a) Sternohyoid (M. sternohyoideus). 

(b) Sternothyreoid (M. sternothyreoideus) . 

Arteries. 

(a) Superior thyreoid artery (A. thyreoidea superior). 

Nerves. 

(a) Muscular rami to M. sternohyoideus and M. sternothyreoideus 

(from the ramus descendens N. hypoglossi). 

(b) External ramus of superior laryngeal nerve (ramus externus N. 

laryng. sup.). 

(c) Recurrent laryngeal nerve (N. recurrens N. vagi). 

Viscera. 

(a) Larynx. 

(b) Trachea. 

(c) Thyreoid gland (glandula thyreoidea). 

(d) Oesophagus (on left side). 

Structures in the Anterior Median Line of the Neck and near it. 
(See Fig. 92, p. 221.) 

These should now be successively examined and studied. 

Suprahyoid Region. 

(a) Platysma. 

(b) Fascia superficial. (Note double chin.) 

(c) Space between anterior bellies of Mm. digastrici of two sides. 

(d) Mylohyoid muscles (Mm. mylohyoidei) and raphe between them. 
Infrahyoid Region. 

(a) Hyothyreoid membrane (membrana hyothyreoidea) (0. T. thyro- 

hyoid membrane). 

(b) Thyreoid cartilage (cartilago thyreoidea}. 



DISSECTION OF THE HEAD AND NECK 



223 



FIG. 93. 



Lympho- 
glandulae 
auriculares 
anteriores 



Lympho- 

glandulae ~ 
auricu- 
lares 
poste- 
riores 

Lympho- 
glandulae 
occipitales 

M. sternodcido 
mastoidcus (cut off] 
Lymphoglandulae eervi- *- 
cales profundae 

snperiores 

Lymphoglandulae eervicales 
profundae inferiores 

Ductus f Truncusjugularis 
lymphaticusj 

dexter Truncus su bclavius 



Lymphoglandulae parotideae 
V. facialis anterior 



Mucous membrane of the lip 



, Lymphoglandulae 
submaxillares 



Union with the lymphoglandulae 
mediastinales antenores 




Lymphoglandulae 

Lymphoglandulae peetoralcs 



ih-ducts 
of tin- 
breast glands 



The lymphatic vessels of the head, the deep lymphatic vessels and lymph-glands of the neck and 
axillary space, and the lymphatic vessels of the female breast. ( After Toldt, Anat. Atlas, Wien, 1900, 
2 Aufl., p. 703, Fig. 1085. ) 



224 



LABORATORY MANUAL OF HUMAN ANATOMY 



(c) Elastic cone and middle cricothyreoid ligament (conus elasticus, 

ligamentum cricothyreoideum [medium}} (0. T. cricothyroid 
membrane). Upon it lies the ramus cricothyreoideus of the A. 
thyreoidea superior. 

(d) Cricoid cartilage (cartilago cricoidea). 

(e) Cricothyreoid muscles (Mm. cricothyreoideae) . 
(/) Trachea. 

FIG. 94. 



M. sternocleidomastoideus. 
M. omohyoidcus 



M. scalenus medius 
...M. thyreohyoideus 



M. trapezoideus 
M. scalenus posterior 




M. omchyoideus 



M. scalenus 

medius 

...M. sternothy- 
reoideus 

- -M. scalenus 
posterior 



C 



Muscles of the neck. (From Poirier et Charpy, Traite" d'Anat. hum., Paris, 1901, 2 ed., t. ii. 

p. 395, Fig. 249. ) 

(g) Isthmus of thyreoid gland (isthmus glandulae thyreoideae] . 

(h) Pyramidal lobe of thyreoid gland (lobus pyramidalis [Gl. thy- 

reoideae]). 

(i) Inferior thyreoid veins (Vv. thyreoideae inferiores). 
(j) Innominate artery (A. anonyma). 

(ja) Lowest thyreoid artery (A. thyreoidea ima). 
(k) Left innominate vein (V. anonyma sinistra). 
(I) Thymus. 

Surgical Anatomical Points. 

In the operation of laryngotomy the ligamentum cricothyreoideum is 
cut through transversely in its lower part, inferior to the ramus crico- 
thyreoideus of the A. thyreoideus superior. 



DISSECTION OF THE HEAD AND NECK 225 

In the operation of tracheotomy the incision into the trachea is prefer- 
ably made between the cricoid cartilage and the isthmus of the thyreoid 
gland (so-called high operation). 

Muscles of the Neck. 

Study the form, position, insertion, and innervation of the 
following muscles : 

Those of the Second Layer. 

(a) Digastric muscle (M. digastricus) . 

(b) Stylohyoid muscle (M. stylohyoideus) . 

These are supplied by Nn. cerebrales. 
Those of the Third Layer. 

(a) Omohyoid muscle (M. omohyoideus) . 

(b) Sternohyoid muscle (M. sternohyoideus) . 

(c) Sternothyreoid muscle (M. sternothyreoideus) . 

(d) Thyreohyoid muscle (M. thyreohyoideus) . 

These are supplied by branches of the Nn. cervicales running 
in the descending ramus of the N. hypoglossus. 

The Sternoclavicular Joint and the Ligaments about the Clavicle, 

Sternum, and First Rib. 

The dissector of the upper extremity has removed the M. 
pectoralis major from the clavicle and sternum, and the sterno- 
clavicular joint (articulatio sternoclavicularis) may now be 
studied. (Cf. Spalteholz, Fig. 227.) What bony surfaces are 
here concerned ? Note the following : 

(a) Sternoclavicular ligament (Lig. sternoclaviculare) . 

(b) Interclavicular ligament (Lig. interclaviculare) . 

(c) Costoclavicular ligament (Lig. costoclaviculare) (0. T. rhomboid liga- 

ment). 

Cut through these ligaments and pull the clavicle lateralward 
so as forcibly to open the Sternoclavicular joint. Observe that 
the articular disk of fibrocartilage (discus articularis) separates 
two joint-cavities, each with a special capsule (capsula articu- 
laris} . 

The Root of the Neck. 

Remove with great care the areolar tissue at the root of the 
neck, avoiding injury to the finer rami of the sympathetic system. 
Study the structures on both sides of the body. 

Muscles. 

(a) Anterior , scalene (M. scalenus anterior). 

(b) Middle scalene (M. scalenus medius). 

(c) Posterior scalene (M. scalenus posterior). 

15 



226 LABORATORY MANUAL OF HUMAN ANATOMY 

(d) Smallest scalene (M. scalenus minimus] (inconstant). 

Study the relation of these to surrounding structures and note espe- 
cially the very important structures related to the most anterior of the 
three muscles. 

Arteries. 

(a) Subclavian artery (A. subclavia). (Vide Fig. 16.) 
Branches : 

Medialward from the M. scalenus anterior. 

(aa) Vertebral (A. vertebralis) . 

(ab) Internal mammary (A. mammaria internet). 

(ac) Thyreocervical trunk (truncus thyreocervicalis) . 

(aca) Inferior thyreoid (A. thyreoidea inferior}. 

(acb) Ascending cervical (A. cervicalis ascendens). 
(ace) Superficial cervical (A. cervicalis superficialis) . 
(acd) Transverse scapular (A. transversa scapulae). 

Behind the M. scalenus anterior. 

(ad) Costocervical trunk (truncus costocervicalis) (0. T. supe- 

rior intercostal). 

(ada) Highest intercostal artery (A. intercostalis su- 

prema) (0. T. superior intercostal proper). 

(adb) Deep cervical artery (A. cervicalis profunda). 
Between the Mm. scaleni. 

(ae) Transverse artery of neck (A. transversa colli). 
Veins. 

(a) Right and left innominate veins (Vv. anonymae dextra et sinistra). 

(aa) Inferior thyreoid veins (Vv. thyreoideae inferiores). 

(ab) Inferior laryngeal vein (V. laryngea inferior}. 

(ac) Lowest thyreoid vein (V. thyreoidea ima). 

(ad) Unpaired thyreoid plexus (plexus thyreoideus impar). 

(ae) Vertebral vein (V. vertebralis) . 

(aea) Deep cervical vein (V. cervicalis profunda). 

(b) Lower part of internal jugular vein (V. jugularis interna). 

(ba) An inferior thyreoid vein (V. thyreoidea inferior). 
Note the bulbus venae jugularis inferior. 

(c) Subclavian vein (V. subclavia). 

(ca) Thoraco-acromial vein (V. thoraco-acromialis) . 

(cb) Transverse vein of neck (V. transversa colli). 

Lymphatics. 

(a) Thoracic duct (ductus thoracicus). (Vide Fig. 93.) 

(b) Right lymphatic duct (ductus lymphaticus dexter). 

These may easily be mistaken for veins when first met with by the 
student. 

Nerves. (Vide Fig. 92.) 

(a) Phrenic nerve (N. phrenicus). Why should this nerve, arising in 

the neck, supply a muscle situated at the lower opening of the 
thorax? 

(b) Vagus nerve (N. vagus). Note its relation to the M. scalenus ante- 

rior, the trachea, and the A. carotis communis. 

(c) Lower part of cervical part of sympathetic trunk (truncus sym- 

pathicus). 



DISSECTION OF THE HEAD AND NECK 



227 



(ca) Middle cervical ganglion (ganglion cervicale medium). 

Does it rest on the A. thyreoidea inferior? 

(cb) Inferior cervical ganglion (ganglion cervicale inferius). 

Look for it in the depression between the transverse 
process of the seventh cervical vertebra and the neck of 
the first rib. 

(cc) Superior cardiac nerve (N. cardiacus superior). 

(cd) Middle cardiac nerve (N. cardiacus medius). 

(ce) Inferior cardiac nerve (N. cardiacus inferior). 

(cf) Subclavian loop (ansa subclavia [ Vieussenii] ) . 
(eg) Subclavian plexus (plexus subclavius). 



FIG. 95. 



M. trapeziu 
M. splenius 
M. spinalis cervicis^ 

M. inter spinali 
M. semispinalis cervic 
M. semispinalis capitis 

M. 



Lig. nuchae 

Lamina prof unda} -r^ - 

Lamina super-\- Fa * a 
' ficwlu? \ 



M. levator scapulae ____ 
M. longissimus capitis ___ 
M. longissimus cervicis..,- 
M. iliocostalis cervicis^- 
M. scalenus medius.* 
Lymphoglandulae 
cervical es profundae"' 

infenores 
M, sternocleidomastoideus 

Vagina vasorum 




Platysma / , 
M. scalenus anterior / / 
M. longus capitis / f 
M. longus cotti / 
M. omohyoideus / 
M. sternothyreoideus / 
M. sternohyoideus / 
V. mediana colli 



of the IV. cervical vertebra 
V. cervicalis profunda 

Sinus vertebralis longi- 

tudinalis 
. vertebralis 



^.Fascia praevertebralis 
Lam. superflc. \ Fascia 
-.Lam. profunda) cotti 

-.interna ) -. . . , 
[ V. jugulans 

-externaJ 

N. cervicalis descendens 
N. vagus 
Truncus sympathicus 

A. carotis communis 
Ramus descendens N. h 
, A. and V. thyreoidea su 
\ \ V. jugularis anterior 

Jfascia praevertebralis 
-, Cavum pharyngis (pars laryngea) 
kima glottidis 



Cross-section through the neck at the level of the rima glottidis and through the body of the fifth 
cervical vertebra. Cut surface below the plane of section. (After Toldt, Anat. Atlas, Wien, 1900, 
2Aufl.,p. 608, Fig. 984.) 



Viscera. 

(a) Summit of pleura (cupula pleurae). 

How far above the level of the sternal extremity of the clavicle 
does it extend into the neck? Which is higher, the left or the 
right? Is there a M. scalenus minimus or tensor of the cupula 
pleurae present? What is Sibson's fascia? What structures 
come into contact with the cervical pleura on the right side? 
What on the left? 

Note the fibrous expansions helping to support and fix the 
cupula (cf. Poirier et Charpy, t. iv., Figs. 250-252) : 

(1) From the apex of the dome to the fourth to seventh cer- 
vical vertebrae. 



228 LABORATORY MANUAL OF HUMAN ANATOMY 

(2) From the lower half of the dome to the visceral sheath of 

the deep cervical fascia (pretracheal aponeurosis). 

(3) From the sixth and seventh cervical vertebrae to the first 

rib, often replacing the M. scalenus minimus. This is 
the ligamentum costopleurovertebrale. 

(4) From the anterior surface of neck of first rib to anterior 

surface of cupula. This is the ligamentum costopleu- 
rale. 

The two latter ligaments may be absent altogether. 

(b) Apex of lung (apex pulmonis). 

(c) Trachea, 

(d) Oesophagus. 

Cervical Plexus. (Vide Figs. 90 and 122.) 

The cervical plexus (plexus cervicalis) should now be studied. How 
is it formed ? What is its relation to the brachial plexus ? What are its 
exact situation and relation to surrounding parts? What muscles re- 
ceive their innervation from it? Review the communications formed 
by the cervical plexus with the cerebral nerves (N. hypoglossus, N. 
vagus, N. accessorius) . How is the sympathetic nervous system related 
to the cervical plexus ? Make drawings or diagrams to show the cervical 
plexus and its relations as they exist in your cadaver. 

General Review of Blood-vessels of Side of Neck. 

The dissector should now make a systematic review of all the blood- 
vessels of the side of the neck, reading on the structures from his text- 
book and making a sketch of the large arteries and their branches and 
the large veins and their tributaries. 

Further Study of Viscera of Neck. 

(a) Thyreoid gland (glandula thyreoidea). 

(aa) Isthmus of thyreoid (isthmus Gl. thyreoideae) . 

(ab) Pyramidal lobe (lobus pyramidalis) (inconstant). 
(oc) Right and left lobes (lobi dexter et sinister). 

(ad) Lobules of gland (lobuli Gl. thyreoideae) . 

(ae) Stroma of gland (stroma Gl. thyreoideae}. 

Are any accessory thyreoid glands present? 

(b) Trachea. 

(ba) Tracheal cartilages (cartilagines tracheales). 

(bb) Annular ligaments (Ligg. annulares trachealia). 
(be) Membranous wall (paries membranacea) . 

(c) Cervical part of gullet (oesophagus, pars cervicalis). 



BACK OF HEAD, NECK, AND TRUNK. 

The dissectors of the head and neck work in conjunction with 
those of the upper extremity. 

Make an incision in the middle line from the inion to the 
spine of the vertebra prominens, a second from the spine lateral- 
ward to the medial border of the acromion, and a third from the 
inion transversely lateralward (vide Fig. 3). Reflect the skin, 



DISSECTION OF THE HEAD AND NECK 229 

taking no fat with it; the superficial fascia (fascia superficialis) 
is thus exposed. Why should the pain accompanying inflamma- 
tion at the nape of the neck as, for example, in carbuncle be 

particularly severe I 

Superficial Vessels and Nerves. (Vide Fig. 4, p. 47.) 

Remove the superficial fascia piecemeal. The A. and V. 
occipitalis have already been met with in the dissection of the 
scalp, as have the terminals of the N. occipitalis major and M. 
occipitalis minor. The trunk of the N. occipitalis major pierces 
the M. trapezius; note exact spot, usually about two and one- 
half centimetres below the inion and one centimetre from the 
middle line. Is a N. occipitalis tertius present! If so, where 
does it pierce the M. trapezius and how is it related in distribu- 
tion to the N. occipitalis major? Find the dorsal cutaneous 
branches of the fourth, fifth, sixth, seventh, and eighth cervical 
nerves (rami cutanei dor sales Nn. cervicalium IV., V., VI., VII., 
VIII.}. Ascertain as closely as possible the area of skin inner- 
vated by each. 

Isolate the great auricular nerve (N. auricularis magnus) 
and follow its posterior branch (ramus posterior] ; its anterior 
branch (ramus anterior] will be studied later. 

Dissect out the cutaneous branches of the superficial cervical 
artery (A. cervicalis superficialis} and of the transverse artery 
of the scapula (A. transversa scapulae}. Note the correspond- 
ing veins. Into what lymph-glands do the lymphatics from this 
region empty? Make a drawing of the dissection at this stage. 

Upper Part of the Posterior Triangle of the Neck. 

Clean the surface of the trapezius muscle (M. trapezius} and 
the posterior border of the sternocleidomastoid muscle (M. 
sternocleidomastoideus} , which form the posterior and anterior 
boundaries of the triangle. Do not raise the M. sternocleidomast- 
oideus and take care not to disturb the nerves which lie beneath 
it at this stage of the dissection. Clean the floor of the triangle. 
Note the direction of the fibres of the splenius muscle of the 
head (M. splenius capitis} and of the elevator muscle of the 
scapula (M. levator scapulae} (0. T. levator anguli scapulae). 
Avoid injury to the rami musculares of the plexus cervicalis 
supplying the latter muscle; they lie usually upon its surface in 
close apposition with it. How is the apex of the triangle formed? 
Is the semispinalis muscle (M. semispinalis capitis} (0. T. corn- 
plexus) visible? If so, in what direction do its fibres run? Is 



230 LABORATORY MANUAL OF HUMAN ANATOMY 

the occipital artery (A. occipitalis) to be seen in the triangle? 
Dissect out the portion of the accessory nerve (N. accessorius) 
belonging to the triangle. Note its exact point of emergence 
from the substance of the M. sternocleidomastoideus. Find the 
rami nmsculares of the plexus cervicalis which run across the 
triangle to disappear beneath the anterior margin of the M. 
trapezius. How are they related in position to the N. accesso- 
rius? Do you find any large cutaneous nerve of the cervix 
(N. cutaneus cervicis) I 

Broad Muscles of the Back (First Layer). (Vide Fig. 5, p. 49.) 

(a) Trapezius muscle (M. trapezius). After its surface has been thor- 
oughly cleaned, in conjunction with the dissector of the upper ex- 
tremity, the exact origin and insertion of the M. trapezius are to 
be established. Test the effect of contraction of its various por- 
tions, fixing alternately the head and the shoulder girdle. With the 
dissector of the upper limb, reflect the muscle and dissect the 
structures on its deep surface. Divide the attachment to the linea 
nuchae superior and protuberantia oecipitalis externa and cut 
through it about one centimetre from the cervical vertebral spines 
and five centimetres from the thoracic spines, taking care that the 
knife does not injure the underlying structures. Turn the muscle 
lateralward and allow the dissector of the upper limb to work out 
the distribution of the N. accessorius and the nerves from the 
cervical plexus going to the M. trapezius. Determine the origin 
and distribution of the A. cervicalis superficialis. In your cadaver 
does it come from the truncus thyreocervicalis or from the A. trans- 
versa colli? 

(ft) Broadest muscle of back (M. latissimus dor si}. The dissector of the 
arm has worked this muscle out and the dissector of the head should 
review his knowledge of it. 

(c) Elevator muscle of scapula (M. levator scapulae] (0. T. levator 
anguli scapulae) and neighboring vessels and nerves. Ex- 
amine the M. levator scapulae and the nerves on its surface 
(from the plexus cervicalis). Lift the muscle carefully and 
find beneath it 

(ca) Descending branch (ramus descendens] of the A. transversa 

colli, often called the " posterior scapular artery." 

(cb) Dorsal nerve of scapula (N. dorsalis scapulae] (0. T. nerve 

to the rhomboids). Note the twigs from this nerve to the 
M. levator scapulae. 

Establish the exact origin and insertion of the muscle 
and test its action. 

Expose the scapular portion of the inferior belly (venter 
inferior] of the M. omohyoideus, and note the position of the 
A. transversa scapulae (0. T. suprascapular, or transversalis 
humeri) and the suprascapular nerve (N. suprascapularis) and 



DISSECTION OF THE HEAD AND NECK 231 

the relation of each to the ligamentum transversum scapulae 
superius. Make a drawing of the part of the posterior triangle 
dissected and read in your systematic text-book descriptions of 
the various structures. 

Broad Muscles of the Back (Second Layer). (Fig. 96.) 

The larger and smaller rhomboid muscles (M. rhomboideus 
major, M. rhomboideus minor) have been worked out by the dis- 
sector of the arm. and may be conveniently reviewed. 

Broad Muscles of the Back (Third Layer). (Fig. 96.) 

The dissector of the head and neck now proceeds with the 
dissection of the muscles of the back, and permits the dissector 
of the upper extremity to study the parts. Observe the fascia 
nuchae. 

(a) Superior posterior serratus muscle (M. serratus posterior superior). 

Note its form and position. Establish its exact origin and inser- 
tion. Test its action. Is it concerned in inspiration or expiration? 
Find the nerves supplying it. What are they called? Is it a 
monomeric or a polymeric muscle ? Divide it close to its attachment 
to the vertebral spines and reflect it lateralward. 

(b) Inferior posterior serratus muscle (M. serratus posterior inferior). 

(c) Splenius ("bandage") muscle of head (M. splenius capitis). 

(d) Splenius muscle of neck (M. splenius cervicis) (0. T. splenius colli). 

Lumbodorsal Fascia (Fascia lumbodorsalis). (Vide Figs. 5 and 6.) 

The posterior layer of this fascia is now visible. That por- 
tion which corresponds to the thoracic spine is often spoken of as 
the " vertebral aponeurosis"; that portion corresponding to 
the small of the back is often called the ' ' lumbar fascia. ' ' 

Examine the posterior layer of the fascia lumbodorsalis. 
What are its medial and inferior attachments? How is it at- 
tached lateralward? What becomes of it above? These ques- 
tions may be answered (1) by making an incision through it in 
the middle of the thoracic region and passing the handle of the 
scalpel medialward and lateralward, and (2) by dividing the 
lumbar portion by a vertical cut made two or three centimetres 
from the median line and raising it from the subjacent M. sacro- 
spinalis. Then displace the M. sacrospinalis medialward and 
expose the anterior layer of the fascia lumbodorsalis. How is 
the anterior layer attached medialward? Note the fusion of the 
anterior and posterior layers lateralward. Cut through the 
anterior layer close to its medial attachment and lift it from the 



232 



LABORATORY MANUAL OF HUMAN ANATOMY 



FIG. 96. 



suprema 
Linanuchae isuperior. 

M. semispinalis capitis 



M. sternocleidomastoideus 
(cut off and turned back) 

f capitis 
M. splenius< 

I cervicis 



M. levator scapulae 
M. serratus posterior superior 



Fascia 
lumbodorsalis 



Mm. intercostales 
externi 



M. serratus posterior 
inferior 



M. latissimus dorsi 



M. obliquus internus 
abdominis 

M. obliquus externus. 
abdominis 

Fascia lumbodorsal 



M. glutaeus medi 



M. glutaeus maximus 



Sutura lambdoidea 

Lig. nuchae 
Fascia nuchae (lamina profunda) 

Processus spinosus vertebrae cervicalis VII. 
M. serratus posterior superior 

M. rhomboideus minor 

M. rhomboideus major 




Processus spinosus 
vertebrae thoracalis XII. 



M. latissimus dorsi 



. obliquus externus 

abdominis 

Trigonum lumbale 

(Petiti) 

Cristailiaca 



Fascia glutaea 



The second layer of the broad muscles of the back, shown after removal of the latissimus dorsi and 
trapezms muscles; on the left side the rhomboid muscles also have been taken away. (AfterToldt, 
Anat. Atlas, Wien, 1900, 2 Aufl., p. 267, Fig. 505.) 



DISSECTION OF THE HEAD AND NECK 233 

surface of the M. quadratus lumborum. Displace the latter 
medialward and the fascia covering the anterior surface of the 
latter will be brought into view. (This fascia was formerly 
called the anterior layer of the lumbar fascia.) Make a drawing 
of the structures in your cadaver corresponding to Spalteholz, 
Fig. 334. 



Long Muscles of the Back (First and Second Layers) (O. T. Third 
Layer of the Back). (Vide Fig. 4, p. 47.) 

Cut through the attachments of the M. splenius capitis and 
M. splenius cervicis, close to the spines of the vertebrae, and 
reflect the muscles upward and lateralward. Turn the whole of 
the posterior layer of the fascia lumbodorsalis with the M. ser- 
ratus posterior inferior lateralward. 

(a) Sacrospinal muscle (M. sacrospinalis) (0. T. erector spinae). What 
are the names given to the three main divisions of this 
muscle? Which is the largest of the three, and which the 
smallest? Pull the M. iliocostalis lateralward on the right 
side; reflect it on the left. Blood-vessels and nerves 
emerge between the M. iliocostalis and the M. longissimus 
dorsi and are the guide in dissection. (Vide Spalteholz, 
Fig. 336.) 

(aa) Lateral subdivision: iliocostal muscle (M. iliocostalis). 

(aaa) Iliocostal muscle of loins (M. iliocostalis lumborum) 

(0. T. sacrolumbalis). 

(aab) Iliocostal muscle of back (M. iliocostalis dorsi) (0. 

T. musculus accessorius). 

(aac) Iliocostal muscle of neck (M. iliocostalis cervicis) 

(0. T. cervicalis ascendens). 

Establish the exact origin and insertion of each. Test 
action. Find innervation. 

(ab) Middle subdivision: longest muscle (M. longissimus). 

(aba) Longest muscle of back (M. longissimus dorsi). 

(abb) Longest muscle of neck (M. longissimus cervicis) 

(0. T. transversalis cervicis). 

(abc) Longest muscle of head (M. longissimus capitis) (0. 

T. trachelomastoid). 

Establish exact origin and insertion of each. Test action. 
Find innervation. 

(ac) Medial subdivision: spinal muscle (M. spinalis). 

(aca) Spinal muscle of back (M. spinalis dorsi). 

(acb) Spinal muscle of neck (M. spinalis cervicis) (0. T. 

spinalis colli). 
(ace) Spinal muscle of head (M. spinalis capiti*). 

Establish exact origin and insertion of each. Test action. 
Find innervation. 



234 LABORATORY MANUAL OF HUMAN ANATOMY 

Short Muscles of the Back (First, Second, and Third Layers). 

(Vide Spalteholz, Figs. 338, 339, and 340.) 
Cut away the attachments of the M. spinalis dorsi and reflect 
the M. longissimus dorsi lateralward. Reflect the M. longissimus 
capitis lateralward and upward. The M. semispinalis is now 
exposed. Clean it thoroughly. While cleaning the M. semi- 
spinalis capitis avoid injuring the posterior cutaneous rami of 
the cervical nerves (rami cutanei posteriores Nn. cervicalium) 
emerging from the substance of the muscle near the middle line. 

(a) Semispinal muscle (M. semispinalis). (Cf. Spalteholz, Fig. 338.) 

(aa) Semispinal muscle of back (M. semispinalis dorsi). 

(ab) Semispinal muscle of neck (M. semispinalis cervicis) (O. T. 

semispinalis colli). 

(ac) Semispinal muscle of head (M. semispinalis capitis) (0. T. 

complexus). 

Establish exact form, position, origin, insertion, action, and in- 
nervation of each. 

Cut away the attachments of the M. semispinalis from the ver- 
tebral spines and from the transverse processes, and study 

(b) Multifidus ("much-divided") muscle (M. multifidus). 

What is its origin? Establish insertion, action, and innervation. 

Cut away the M. multifidus and expose the third layer of short 
muscles. Observe in the sacral region the posterior rami of the 
sacral and coccygeal nerves (rami posteriores Nn. sacralium et 
N. coccygei). 

(c) Rotator muscles (Mm. rotatores). 

(ca) Long rotator muscles (Mm. rotatores longi). 

(cb) Short rotator muscles (Mm. rotatores breves). 

(d) Elevators of the ribs (Mm. levatores costarum). 

(da) Short elevators of the ribs (Mm. levatores costarum breves). 

(db) Long elevators of the ribs (Mm. levatores costarum longi). 

(e) Interspinal muscles (Mm. interspinales) . 

(f) Intertransverse muscles (Mm. intertransversarii) . 

(fa) Cervical. 

(faa) Anterior (Mm. intertransversarii anteriores). 

(fab) Posterior (Mm. intertransversarii posteriores) . 

(fb) Lumbar. 

(fba) Medial (Mm. intertransversarii mediales). 

(fbb) Lateral (Mm. intertransversarii laterales). 

Short Muscles of the Neck. (Cf. Spalteholz, Fig. 341). 

Carefully clean the surface of the following muscles : 

(a) Larger posterior straight muscle of head (M. rectus capitis posterior 

major). 

(b) Lesser posterior straight muscle of head (M. rectus capitis posterior 

minor). 

(c) Superior oblique muscle of head (M. obliquus capitis superior). 

(d) Inferior oblique muscle of head (M. obliquus capitis inferior). 



DISSECTION OF THE HEAD AND NECK 235 

Find the posterior ramus of the suboccipital nerve (ramus 
posterior N. suboccipitalis), the branches of which supply all 
four. Establish the origin, insertion, and action of each muscle. 

What are the boundaries of the " suboccipital space, or 
triangle' 7 ? (Fig. 97.) Note in the space 

(a) Posterior ramus of the first cervical nerve (N. sub occipitalis}. 

(b) Portion of the vertebral artery (A. vertebralis). 

Examine the floor of the space and distinguish 

(a) Posterior arch of the atlas (arcus posterior atlantis). 

(b) Posterior atlanto-occipital membrane (membrana atlanto-occipitalis 

posterior). 

Blood-vessels and Nerves of Neck and Back. 

The more superficial vessels of the neck have already been 
studied. The student should carefully work out the following : 

Arteries. (Fig. 97.) 

(a) Occipital artery (A. occipitalis). How is it related to neighboring 

structures ? 

(aa) Muscular rami (rami musculares). 

To what muscles are these distributed? Note espe- 
cially the descending ramus (ramus descendens) (0. T. 
arteria princeps cervicis). 

(ab) Mastoid branch (ramus mastoideus). 

Into what foramen does this enter? 

(ac) Auricular branch (ramus auricularis ) . 

(ad) Occipital branches (rami occipitales) . 

(b) Ascending cervical artery (A cervicalis ascendens). 

(ba) Muscular branches (rami musculares). 

(bb) Deep ramus (ramus profundus). 

(c) Deep cervical artery (A. cervicalis profunda). 

With what vessels does this artery anastomose ? 

(d) Posterior ramus of highest intercostal artery (ramus posterior A. 

intercostalis supremae). 

(e) Posterior rami of intercostal arteries (rami posteriores Aa. inter- 

costalium). 

(ea) Muscular branches (rami musculares). 

(eb) Medial cutaneous rami (rami cutanei mediales). 

(ec) Lateral cutaneous rami (rami cutanei laterales). 
Veins. 

(a) Occipital vein (V. occipitalis). 

(aa) Mastoid emissary vein (emissarium mastoideum). 

Why are the emissary veins of special importance? 
Why is it a common practice to apply leeches and blisters 
behind the ear in certain intracranial affections? 

(b) Deep cervical vein (V. cervicalis profunda}. 

(c) Posterior rami of intercostal veins (rami posteriores Vv. intercos- 

talium). 



236 



LABORATORY MANUAL OF HUMAN ANATOMY 



(d) Posterior rami of lumbar veins (rami posterior es Vv. lumbalium). 
Nerves. 

In addition to those already studied note the following : 

(a) Posterior rami of cervical nerves (rami posterior es Nn. cervi- 
calium ) . 

(aa) Medial rami (rami mediales). 

(ab) Lateral rami (rami laterales). 



FIG. 97. 



Ramus descendens 



Ramus meningeus of 
the A. vertebralis 



Ramus mastoideu 

A. occipital! 
A. vertebralis - 

Proc. transversus 

attantis 

Posterior belly of the 
M. digastricus 



M. levator - 
scapulae 



M. semispinalis 

capitis 
M. semispinalis 

cervicis 

Proc. spinosus vertebrae 
cervicalis VII. 
A. cervicalis profunda 



A. transversa colli 



M. semispinalis 
dorsi 




Rami occipitales of the 

A. occipitalis 
M. rectus capitis 
posterior minor 
. obliquus capitis 

superior 

Ramus occipitalis of the 
A. auricularis posterior 

M. rectus capitis 
posterior major 

Rami auriculares of 

the A. auricularis 

posterior 

Ramus muscularis of 
the A. vertebralis 

A. vertebralis 



M. semispinalis capitis 

Ramus profundus of 
the A. cervicalis 

ascendens 
M. semispinalis cervicis 

A. cervicalis profunda 

". semispinalis cermcis 

Ranms dorsalis of the A. 

intercostalis suprema 
M. scalenus posterior 

.Ramus ascendens ] of the 
\ A. trans- 

.Ramus descendensl versa colli 



..M. iliocostalis 
cervicis 



The arteries of the posterior region of the head and the deep arteries of the neck. 
(After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 597, Fig. 972.) 

(b) Posterior rami of thoracic nerves (rami posterior es Nn. thora- 
calium ) . 

(ba) Medial rami (rami mediales) . 

(bb) Lateral rami (rami laterales). 



DISSECTION OF THE HEAD AND NECK 237 

(c) Posterior rami of lumbar nerves (rami posteriores Nn. lum- 

balium ) . 

(ca) Medial rami (rami mediates) . 

(cb) Lateral rami (rami later ales). 

(d) Posterior rami of sacral and coccygeal nerves (rami posteriores 

Nn. sacralium et coccygei). 

Opening the Vertebral Canal. 

Carefully remove all muscles and tendons from the spinous 
processes and arches of the vertebrae from the occipital bone to 
the tip of the coccyx, avoiding injury, however, to the posterior 
rami of the spinal nerves (rami posteriores Nn. spinalium). 
Place high blocks under the thorax and let the head hang over 
the end of the table. 

The vertebral canal (canalis vertebralis) may be opened from 
behind in any one of four different ways: (a) with the double 
rhachiotome, (b) with a saw, (c) with mallet and chisel, (d) 
with bone-forceps. 

(a) With the Double Rhachiotome. Place the saws of Luer's double 
rhachiotome on the cervical portion of the vertebral column; seize the 
handle with the right hand, pressing down from above upon the rhachi- 
otome with the left hand; saw (in the direction in which the teeth are set) 
with quick, rapidly repeated strokes through the vertebral arches. As 
soon as the saw has gone through, the same process is repeated a little 
lower down, and so on until the whole posterior wall of the vertebral 
column has been cut through as far as the last lumbar vertebra. Between 
the last lumbar vertebra and the sacrum cut through the ligamenta flava; 
introduce the vertebral forceps below the posterior arch of the last lumbar 
vertebra, seize hold of it and, grasping the forceps with both hands, tear 
away in one piece the whole posterior wall of the vertebral canal from 
the lumbar region to the occipital bone. If the cervical portion be not 
quite sawn through, apply the rhachiotome again and cut in a reverse 
direction. 

( b ) With a Saw. One may use a simple saw, cutting through first one 
side and then the other. The saw should pass close behind the articular 
processes and should be directed slightly obliquely, so that the cut passes 
a little medialward in the depth. It may be necessary to use the hammer 
and chisel also. Neelsen recommends the use of the " fox-tail saw." 

(c) With Mallet and Chisel The vertebral arches may be chiselled 
instead of sawn through, if desired, but the tyro is apt to injure the cord. 
Special chisels (one for each side) are manufactured for the purpose, but 
a good heavy plain chisel works well. 

(d) With Bone-forceps. Cut through the root of each vertebral arch 
(radix arcus vertebrae} (0. T. pedicle) on each side, just ventral to the 
superior articular processes, and thus remove the whole posterior wall of 
the vertebral canal. This method has the advantage that it opens up all 
intervertebral foramina and permits of the removal of the spinal ganglia 
and the proximal portion of each spinal nerve along with the spinal cord. 



238 LABORATORY MANUAL OF HUMAN ANATOMY 

It will be well also to remove the posterior wall of the spinal canal in the 
sacrum and coccyx. 

The cord lying in its external covering, the dura mater, or 
pachymeninx spinalis, is now exposed. Notice the interspace 
between the third and fourth lumbar vertebrae. This is the site 
of Quincke 's ' ' lumbar puncture. ' ' Here a needle can be intro- 
duced into the cavum subarachnoideale during life without 
danger. 

Read carefully the description of the veins of the spinal 
column and study Spalteholz, Figs. 493 and 494. 

Examine carefully 

(a) Spinal ramus of posterior ramus of each intercostal artery (ramus 
spinalis rami post. A. intercostalis) , passing through an interver- 
tebral foramen. (Cf. Spalteholz, Fig. 462.) 

(&) Spinal ramus of posterior ramus of each lumbar artery (ramus spi- 
nalis rami post. A. lumbalis). 

(c) Spinal rami of vertebral artery (rami spinales A. vertebralis) and 
the spinal rami of the ascending cervical artery (rami spinales A. 
cervicalis ascendentis ) . 

Spinal Meninges. (Fig. 98.) 

Clean the external surface of the dura mater, removing fat 
and areolar tissue. Lift the dura gently with fine forceps, and, 
with fine, sharp scissors, cut through the dura mater spinalis in 
the middle line .throughout its whole length. Take great care 
not to injure the spinal arachnoid (ar.achnoidea spinalis). Trace 
the terminal thread of the dura mater (filum durae mat r is spi- 
nalis) to its bony attachment. Note that the dura mater spinalis 
corresponds to the inner layer of the dura mater encephali, the 
outer layer having fused with the periosteum of the vertebral 
canal. The space (cavum epidurale) between the lining of the 
vertebral canal and the dura mater spinalis contains the plexus 
venosi, which in turn correspond to the cerebral sinuses. Note 
disproportion between the size of the cord and the size of the 
dura mater, especially in the regions where the mobility of the 
vertebral column is great. Observe the fibrous filaments from 
the anterior middle line of the dura which run obliquely down- 
ward ventralward to be inserted into the ligamentum longitudi- 
nale posterius; note their excessive development and fusion 
from the fourth lumbar vertebra downward; this is the liga- 
mentum sacrodurale anterius (ligament sacre anterieur of Tro- 
lard). (Cf. Poirier et Charpy, iii., Fig. 77.) What is its 
function? Note the dural sheaths of the nerve roots. 



DISSECTION OF THE HEAD AND NECK 239 

Examine the membrane (arachnoidea spinalis) which bounds 
the cavum subdurale internally. Note that this is what many 
anatomists call the " visceral layer" of the arachnoid; below, 
at the summit of the conus terminal is (second sacral), it is re- 
flected upon the dura mater to form the " parietal layer " of the 
arachnoid; the " arachnoid cavity" of various writers is sit- 




Dura mater spinalis 



.Conus medullaris 



Arachnoidea spinalis 



Cavum subdurale 



Filum terminate 



..7T^:Cavum subarachnoideale 



. Junction of arachnoidea and dura 



Filum terminale 

Arachnoidea spinalis 

x Cavum subdurale 



Dura mater spinalis 



Disposition of the arachnoidea spinalis at the inferior extremity of the medulla spinalis. The 
sections are schematic (longitudinal and transverse). The pia mater is in red. The transverse section 
passes through the cauda equina. (From Poirier et Charpy, Traite d'Anat. hum., Paris, 1899, t. iii., 
1, p. 118, Fig. 83.) 

uated between the parietal layer and the visceral layer, being the 
cavum subdurale of the present nomenclature. It is a serous 
cavity like the pleura. Can you separate the " parietal layer" 
from the dura! Do you see any blood-vessels in the " visceral 
layer"? Are there any calcified plates in the latter? Note the 




240 



LABORATORY MANUAL OF HUMAN ANATOMY 



prolongation of the arachnoid over the nerve roots and over the 
summits of the teeth of the liganientuin denticulatum. 

Lift the visceral layer of the arachnoid, cut through it with 
fine scissors, insert grooved director, and cut it open longitudi- 
nally a little to one side of median line. Examine the space 
(cavum subarachnoideale) beneath the visceral layer of the 
arachnoid and the pia mater. Note the expanse of the space 
especially in the region of the cauda equina, which it contains. 



FIG. 99. 



A 




Portions of the pars cervicalis of the spinal cord with nerve-roots. 

A, spinal cord seen from the ventral surface. On the right side the ventral fila radicularia have 
been cut through. S, spinal cord seen from the lateral surface. 1, fissura mediana anterior ; 2, sulcus 
medianus posterior ; 3, sulcus lateralis ventralis, whence the ventral fila radicularia emerge ; 4, sulci 
laterales dorsales through which the dorsal root fibres enter the spinal cord ; 5, radix ventralis going 
past spinal ganglion cut through on the right side in Fig. A ; 6, radix dorsalis emerging from the 
ganglion spinale (&) 7, N. spinalis immediately after its formation through the union of the radix 
ventralis and dorsalis dividing into 7, a ramus ventralis, and 7', a ramus dorsalis. The ramus com- 
municans and the ramus meningeus are not shown in this figure. (After Allen Thompson, from A. 
Rauber, Lehrbuch der Anatomie des Menschen, V. Aufl., Leipz., 1898, Bd. ii. S. 283, Fig. 248.) 

Where would the cerebrospinal fluid accumulate in greatest 
amount? Note precise spot where cavum subarachnoideale is 
tapped in Quincke's lumbar puncture. There is no communica- 
tion between the cavum subdurale and the cavum arachnoideale. 
Notice the areolar tissue everywhere present between the arach- 
noid and the pia. Make out the septum subarachnoideale pos- 
terius. 

Examine the spinal pia mater (pia mater spinalis). How 



DISSECTION OF THE HEAD AND NECK 



241 



closely does this membrane invest the 
cordf Note its extreme vascularity. 
What is meant by the term " lepto- 
meninx ' ' ? 

Study the lig amentum denticu- 
latum. Where is the medial border 
of the ligament inserted? On the lat- 
eral border note the teeth and the 
free arcades intermediate between the 
teeth. Into what are the summits of 
the teeth inserted! What is the rela- 
tion of the ligamentum denticulatum 
to the anterior and posterior roots? 
The number of teeth varies from eigh- 
teen to twenty-three. How many are 
there in your subject? What is the 
function of the ligament? 

Study the relations of the spinal 
nerve roots to the pia, the arachnoid, 
and the dura. (Cf. Poirier et Charpy, 
iii., Fig. 103.) 

The Spinal Nerves (Nervi spinales). 
(Figs. 99 and 100.) 

Count these on each side. Distin- 
guish the cervical nerves (Nn. cervi- 
cales, I -VIII.}, the thoracic nerves 
(Nn. thoracales, I.-XIL), the lumbar 
nerves (Nn. lumbales, I.-V. ) , the sacral 



Spinal cord in connection above with the medulla 

oblongata and pons. 

V, nervus trigeminus ; XII, nervus hypoglossus; C\, first 
cervical nerve ; C*2-8, second to eighth cervical nerve ; Tl-12, 
first to twelfth thoracic nerve ; L 1-5, first to fifth lumbar 
nerve ; S 1-5, first to fifth sacral nerve ; G, nervus coccygeus ; 
x, x, filum terminale of the spinal cord. From the root 
marked LI to x, cauda equina; Rr, plexus brachialis; CV, 
nervus femoralis ; Sc, nervus ischiadicus ; 0, nervus obtura- 
torius ; the enlargements opposite L 3, 4, and 5 represent 
the spinal ganglia on the dorsal roots. On the left side of 
the figure the sympathetic trunk is shown, a to as are 
ganglia; a, ganglion cervicale superius; & and c, ganglion 
cervicale medium et inferius; d, first thoracic ganglion; 
d', last thoracic ganglion ; I, first lumbar ganglion ; ss, first 
sacral ganglion. (After Allen Thompson, from A. Rauber, 
Lehrbuch der Anatomie des Menschen, V. Aufl., Leipz., 1898, 
Bd. ii. S. 504, Fig. 485. ) 

16 



FIG. 100. 



V 



2 Rr 



242 LABORATORY MANUAL OF HUMAN ANATOMY 

nerves (Nn. sacrales, L-V.), and the coccygeal nerve (N. coccy- 
geus}. Note the subdivision of each spinal nerve trunk into an 
anterior and a posterior ramus. Observe the roots of the spinal 
nerves (radices nervorum spinalium). Where does the ventral 
root (radix anterior) fuse with the dorsal root (radix poste- 
rior) 1 Note the ganglion (ganglion spinale) on the latter. 
What are the fila radicularia? Observe the relative lengths of 
the various nerve roots. How do you account for this? Which 
are the largest and which the smallest nerve roots? Examine 
the cauda equina carefully. How do the nerves leave and enter 
the vertebral canal ? Look for the ramus meningeus. 

Removal of Spinal Cord. 

Divide each spinal nerve trunk midway between the point of 
fusion of its two roots and the point of division into an anterior 
and a posterior ramus. 

Cut through the cord at the level of the first cervical nerve. 
Lift the cord and its membranes gently from the vertebral canal 
and transfer to formalin for subsequent study. 



THE SPINAL COED. 
Blood-vessels of the Spinal Cord. 

As a rule, special injections are necessary to demonstrate the 
blood-vessels of the cord well, but a good deal can be made out 
in ordinary cadavers. Study the following : 

Arteries. 

(a) Branches of vertebral artery (A. vertebralis). 

(aa) Spinal rami (rami spinales). 

(ab) Posterior spinal artery (A. spinalis posterior). 

(ac) Anterior spinal artery (A. spinalis anterior). 

(b) Branches of ascending cervical artery (A. cervicalis ascendens). 

(ba) Spinal rami (rami spinales). 

(c) Branches of highest intercostal artery (A. intercostalis suprema). 

(ca) Spinal rami (rami spinales). 

(d) Branches of intercostal arteries (Aa. intercostales) . 

(da) Spinal ramus of posterior ramus (ramus spinalis rami pos- 
terioris). 

(e) Branches of lumbar arteries (Aa. lumbales). 

(ea) Spinal ramus (ramus spinalis). 

(f) Branch of iliolumbar artery (A. iliolumbalis) . 

(fa) Spinal ramus (ramus spinalis). 

(g) Branches of lateral sacral artery (A. sacralis lateralis). 

(ga) Spinal rami (rami spinales). 



DISSECTION OF THE HEAD AND NECK 243 

(For a description of the course of the vessels in the meninges and 
in the cord itself, see article " Spinal Cord" in last edition of Wood's 
Reference Hand-book of the Medical Sciences.) 
Veins. 

(a) Internal spinal veins (Vv. spindles internae). 

(b) Posterior external spinal veins (Vv. spinales externae posteriores) . 

(c) Anterior external spinal veins (Vv. spinales externae anteriores). 

(d) Intervertebral veins (Vv. intervertebrales) . 

External Morphology of Spinal Cord. 

What is the shape of the spinal cord! How is it curved? 
Note the position and extent of each of the following : 

(a) Cervical portion (pars cervicalis). 

(aa) Cervical enlargement (intumescentia cervicalis). 

(b) Thoracic portion (pars thoracalis) (0. T. dorsal portion). 

(c) Lumbar portion (pars lumbalis). 

(ca) Lumbar enlargement (intumescentia lumbalis). 

(d) Medullary cone (conus medullaris). 

(da) Swelling due to terminal ventricle (ventriculus terminalis). 

(e) Terminal thread (filum terminale). 

On the surface of the cord observe the following grooves : 

(a) Anterior median fissure (fissura mediana anterior). 

(b) Posterior median sulcus (sulcus medianus posterior). 

(c) Anterior lateral sulcus (sulcus lateralis anterior). 

(d) Posterior lateral sulcus (sulcus lateralis posterior). 

(e) Posterior intermediate sulcus (sulcus intermedius posterior) (0. T. 

paramedian furrow). 

(/) Anterior intermediate sulcus (sulcus intermedius anterior) (incon- 
stant). 

Between these grooves the funiculi of the spinal cord (funiculi medullae 
spinalis ) . 

(a) Anterior funiculus (funiculus anterior) (0. T. anterior column). 

(b) Lateral funiculus (funiculus lateralis) (0. T. lateral column). 

(c) Posterior funiculus (funiculus posterior) (0. T. posterior column). 



Transverse Sections of Spinal Cord. (Fig. 101.) 

Sections of the spinal cord (sectiones medullae spinalis) 
should next be studied. With a sharp, thin knife, cut through 
the cord transversely at the following levels: (1) just below 
roots of fourth pair of cervical nerves, (2) through middle of 
cervical enlargement, (3) through middle of thoracic cord, (4) 
through middle of lumbar enlargement, and (5) through conus 
terminalis. In the sections observe the differentiation into white 
matter (substantia alba) and gray matter (substantia grisea). 



244 LABORATORY MANUAL OF HUMAN ANATOMY 

The Gray Matter. 

What is its form in cross-section? How does this vary at 
different levels? Localize the central canal (canalis centralis) 

FIG. 101. 




Cross-sections through the human spinal cord, stained with carmine. 

A, transverse section at the level of C iii : Cg, commissura grisea ; Ap, apex columnse dorsalis ; Ca, 
commissura ventralis alba ; Cc, canalis centralis ; Cm, commissura medullse spinalis ; Cm, cornu ven- 
trale; Crp, cornu dorsale; Fna, funiculus ventralis; FnB, fasciculus cuneatus Burdachi; FnG, 
fasciculus gracilis Golli ; Fnl, funiculus lateralis ; Fsla, flssura mediana ventralis ; Fslp, sulcus medianus 
dorsalis ; k, tractus solitarius ; Pr, formatio reticularis ; .Ra, radix ventralis ; Rp, radix dorsalis ; Sg, 
substantia gelatinosa Rolandi ; Sid, sulcus lateralis dorsalis ; Smd, septum medianum dorsale ; Spd, 
septum intermedium dorsale ; Til, tractus intennedio-lateralis. B, transverse section at the level of 
C vi : Prm, processus cervicalis medius cornu ventralis ; Til, columna intermedio-lateralis. C, trans- 
verse section at the level of T iii : CCl, nucleus dorsalis Clarkii. D, transverse section at the level of 
T xii : CCl, nucleus dorsalis. E, transverse section at the level of L v : m, medial cell group of the 
cornu ventrale ; Iv, lateral ventral, Id, lateral dorsal, and c, central cell group. F, transverse section at 
the level of S iii : m, medial, Id, lateral-dorsal cell group. G, transverse section through the lower part 
of the conus medullaris at the level of origin of the N. coccygeus. ( After H. Obersteiner, Anleitung 
beim Studium des Baues der nervosen Centralorgane im gesunden und kranken Zustande, III. Aufl., 
Leipz. u. Wien, 1896, S. 227, Figs. 96-102. ) 

and the gray matter close to it, the central gray substance (sub- 
stantia grisea centralis). In front of it is the anterior gray com- 



DISSECTION OF THE HEAD AND NECK 245 

missure (commissura grisea anterior] and behind it the posterior 
gray commissure ( commissura grisea posterior) . Study in cross- 
section each of the following gray columns (columnae griseae) : 

(a) Anterior column of gray matter (columna anterior) (0. T. anterior 
horn). 

(6) Lateral column of gray matter (columna lateralis) (0. T. lateral 

horn). 
(ba) Reticular formation (formatio reticularis) . 



FIG. 102. 



.l.d. 




F.m.v. 



5.U. 



N. Spinalis 
R.y. 



Schematic representation of the portion of a spinal cord corresponding to the attachment of the 
ventral and dorsal roots of one pair of spinal nerves. (From Barker, The Nerv. Syst., New York, 1901, 
PI. II. Fig. 2.) 

Black. Cc., canalis centralis; C.d., commissura posterior (O.Y., commissura dorsalis) ; C.d.g., 
columna posterior (O.Y.,cornudorsalegriseum) ; C.v.g., columna anterior (O.Y.,cornuventralegriseum); 
Cm.v.a., commissura anterior alba (O.Y., com. ventralis alba) ; Cm.v.g., commissura anterior grisea (O.Y. 
com. ventralis grisea) ; Fc., funiculus cuneatus; Fg., funiculus gracilis; Fd., funiculus posterior (O.Y. 
funiculus dorsalis); FL, funiculus lateralis; Fv., funiculus anterior (O.Y., fun. ventralis); F.m.v., 
fissura mediana anterior (O.Y., fis. med. ventralis) ; G.sp., ganglion spinale ; R.d., radix posterior nervi 
spinalis (O.Y., rad. dorsalis) ; E.v., radix anterior (O.Y., ventralis) nervi spinalis (O.Y., rad. ventralis) ; 
S.I d., sulcus lateralis posterior (O.Y., sulc. lat. dorsalis) ; S.l.v., sulcus lateralis anterior (O.Y., sulc. lat. 
ventralis) ; S.i.d., sulcus intermedius posterior (O.Y., sulc. intermed. dorsalis) ; S.m.d., sulcus medianus 
posterior (O.Y., sulc. med. dorsalis.) 

Red. Peripheral sensory neurones. The cell-bodies, 1, are situated in the spinal ganglion. The 
peripheral processes enter the peripheral nerves, the central axones pass by way of the radix posterior 
into the funiculus cuneatus of each side. There each axone bifurcates into an ascending and a 
descending limb, giving off also collaterals to the gray substance. 

Blue. Lower motor neurones. The cell-bodies, 1, are situated in the columnae anteriores. They 
send their axones by way of the anterior roots into the peripheral nerves. 

The neural mechanism believed to form the basis of the simplest reflex arc is illustrated in the 
figure. 

(c) Posterior column of gray matter (columna posterior) (0. T. posterior 
horn). 

(ca) Neck of posterior column (cervix columnae posterioris) . 

(cb) Apex of posterior column (apex columnae posterioris). 



246 



LABORATORY MANUAL OF HUMAN ANATOMY 

(cc) Gelatinous substance of Rolando (substantia gelatinosa [Ro- 



(cd) Dorsal nucleus (nucleus dorsalis [Clarkii, Stillingi]) (0. T. 
Clarke's column). 



FIG. 103. 



Comma-shaped bundle 
Middle root-zone \ 



Posterior medial root-zone^ 
Radix posterior 



Lissauer's marginal zone 
(posterior lateral root-zone) 
Fasciculus cerebro- 
spinalis lateralis 
(pyramidalis lateralis) 



Fasciculus 
cerebellospinalis 
Lateral limiting layer 

of the gray matter 
Bundle to lateral funicu- 
lusfrom Deiters's nucleus' 

and the red nucleus 
Fasciculus anterolateral 
superficialis [Gowersil] 

Corpora quadrigemina' 
(thalamus path) 

. Helweg's bundle 
Fila radicularia radicis anterioris 
Bundle connecting formatio reticularis with ' 
anterior funiculus (black : to the formatio / 

reticularis) 
Anterior marginal bundle (bundle to anterior 

funiculus from nucleus fastigii) / 

Commissural bundle 



Fasciculus gracilis [Golli] 

I Oval bundle of posterior funiculus (median root-zone) 

I I Ventral area of posterior funiculus (anterior root-zone) 

Stratum zonale 
(marginal zone) 

Substantia gelatinosa 
[Rolandi] 

Caput cplumnae 
posterioris (nucleus 
of the posterior 
horn) 

- Nucleus dorsalis 
[Stillingi, Clarkii] 




Dorso- 
lateral 



Inter- 
mediate 



Ventral 

(ventrolateral 

and ventro- 

medial) 



Ganglion- 
cell 
groups 

of 

anterior 
horn 



Dorsomedial group of ganglion cells of 
anterior horn 



Fasciculus sulcpmarginalis (bundle from the 
superior colliculi of the corpora quadrigemina) 
Fasciculus cerebrospinalis anterior (pyramidalis anterior) 



Schematic transverse section of spinal cord with conduction paths and groups of ganglion cells. 
Magnification : circa 12.5 : 1 (Held). (All of the paths descending from the brain to the spinal cord are 
in colors ; all other paths in the spinal cord, ascending and descending, are indicated in black.) (After 
Spalteholz, Hand Atlas of Human Anatomy, Leipzig, 1903, vol. iii. p. 671, Fig. 749.) 



The White Matter. 

In the sections recognize in the white matter the position of 
each of the following : 

(a) In the anterior funiculus (funiculus anterior) : 

(aa) Anterior cerebrospinal or pyramidal fasciculus (fasciculus 

cerebrospinalis anterior [pyramidalis anterior]) (0. T. 
direct pyramidal tract). 

(ab) Proper anterior fasciculus (fasciculus anterior proprius 

[Flechsigi]) (0. T. anterior ground-bundle). 

(b) In the lateral funiculus (funiculus lateralis) : 

(ba) Lateral cerebrospinal or pyramidal fasciculus (fasciculus 

cerebrospinalis lateralis [pyramidalis lateralis]) (0. T. 
crossed pyramidal tract). 

(bb) Cerebellospinal fasciculus (fasciculus cerebellospinalis) (0. 

T. direct cerebellar tract of Flechsig). 1 



1 This would be better designated fasciculus spinocerebellaris dorsolateralis. 



DISSECTION OF THE HEAD AND NECK 247 

(be) Superficial anterolateral fasciculus (fasciculus anterolateralis 
super ficialis [Gowersi]) (0. T. Gowers's tract). 

(bd) Proper lateral fasciculus (fasciculus lateralis proprius 
[Flechsigi]) (0. T. lateral ground-bundle). 

(c) In the posterior funiculus (funiculus posterior} : 

(ca) Slender fasciculus (fasciculus gracilis [Golli]) (0. T. column 

or tract of Goll). 

(cb) Wedge-shaped fasciculus (fasciculus cuneatus [Burdachi]) 

(0. T. column or tract of Burdach). 

(d) Anterior white commissure (commissura anterior alba). 



FACE. 
Surface Anatomy. 

The general features of the surface have already been exam- 
ined. The student will do well at this time to make especial 
drawings of the external appearance of the eye and mouth- 
opening. 

The Eye. 

Indicate the eyebrow (superdlium) , with the hairs (super- 
cilia). Examine the lids (palpebrae), closed and open. After 
noting the appearance of the anterior surface (fades anterior 
palpebrarum) , evert each lid and view the posterior surface 
(fades posterior palpebrarum). The slit between is called the 
palpebral fissure (rima palpebrarum). At the junction of the 
two lids are situated the medial and lateral palpebral commis- 
sures (commissurae palpebrarum lateralis et medialis) (0. T. 
external and internal canthi). These are at the lateral and 
medial angles of the eye (anguli oculi lateralis et medialis). 
Observe that the edge of each lid has two margins (limbus palpe- 
bralis anterior, posterior). What is the relation of the eye- 
lashes (dlia) and of the openings of the Meibomian follicles 
(glandulae tar sales [Meibomi]) to these margins? Trace the 
continuity of the palpebral conjunctiva (tunica conjunctiva 
palpebrarum) with the bulbar conjunctiva (tunica conjunctiva 
bulbi). Note the recesses in the region where the palpebral con- 
junctiva is reflected upon the eyeball; these are the superior 
and inferior fornices (fornix conjunctivae superior, inferior). 
Observe the triangular space (lacus lacrimalis) at the medial 
extremity of the rima palpebrarum; in its centre is a reddish 
flesh-like mass, the lacrimal caruncle (caruncula lacrimalis). 
Observe the small vertical semilunar fold of conjunctiva (plica 
semilunaris conjunctivae) just lateral from the caruncle. It cor- 



248 LABORATORY MANUAL OF HUMAN ANATOMY 

responds to the third eyelid, or membrana nictitans, of lower 
animals. The stream (rivus lacrimalis) of tears (lacrimae) run- 
ning over the conjunctiva passes to the medial angle of the eye. 
At the point on each lid where the eyelashes cease is a small 
eminence, the lacrimal papilla (papilla lacrimalis). These 
eminences are perforated, the openings looking like two minute 
black dots (puncta lacrimalia) . The openings lead into small 
canals, lacrimal ducts (ductus lacrimales). Pass a fine bristle 
into each. The lacrimal apparatus will be further studied later. 

The Mouth-opening. 

Note that it is bounded by the two lips (labia on's), one supe- 
rior (labium superius), one inferior (labium inferius). At the 
junction of the lips at the two angles of the mouth (anguli oris) 
are the commissures of the lips (commissurae labiorum). The 
slit between the lips is called the rima oris. Note the curious 
transition between skin and mucous membrane in the lip. 

Skin and Superficial Fascia. 

Observe the thinness and fineness of the skin of the face. 
Compare its mobility with that of other parts. Which portions 
are most firmly attached to subjacent structures? Are any 
comedones visible! Note the distribution of the hairs of the 
beard (barba). Observe the long, rather stiff hairs at the nose 
openings (vibrissae). Through the skin feel the external maxil- 
lary artery where it passes over the margin of the mandible. 
Distend the cheeks and lips with moist cotton and stitch the 
margins of the lips together with a fine needle. 

Make an incision through the anterior median line and re- 
move the skin of the face, taking no fat with it. Avoid injury to 
the upper part of the platysma, the M. risorius, and the struct- 
ures of the eyelids. After the platysma has been carefully 
studied, it may be removed. 

Cutaneous Muscles of Face. (Vide Fig. 104.) 

Note that the majority of the muscles of the face and scalp 
have attachments to the skin; indeed, these muscles have been 
derived by progressive differentiation of a primitive cervico- 
f acial cutaneous muscle ; all of them are innervated by branches 
of the N. f acialis, which is the nerve of the hyoid arch. Observe 
the tendency to a grouping around various orifices, the muscles 
acting as dilators or constrictors of these orifices. What part 
do these muscles play in facial expression? 



DISSECTION OF THE HEAD AND NECK 



249 



Platysma. 

Muscles of the external ear. 

(a) M. auricularis anterior (already studied). 

(b) M. auricularis posterior (already studied). 

(c) M. auricularis superior (already studied). 
Muscles of the eyelids. 

Dilators. 

(a) M. epicranius (already studied). 

Note that the principal dilator, the M. levator palpebrae superioris, 
is not a skin-muscle. 

FIG. 104. 



Pericranium^ 
M. orbicularis oculi 
(parsorbitalis) 
M. corrugator 
supercilii.. 



M. orbicularis oculi 
(pars palpebralis) 

Ltg. palpebrale 
mediate 
M. procerus 



M. quadra- 

tus labii 

superioris 



M. auricularis 
superior 



M. auricularis 
anterior 



Caput 

angulare 

Caput 

infra- 

orbitale 




... M. caninus 
M. zygomaticus 
M. risorius 

M. triangularis 

> 

Platysma 



M. quadratus labii inferioris 

M. transversus menti ( Var. 



The muscles of the face. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 296, Fig. 537.) 



Constrictors. 

(a) Procerus ("prolonged") muscle (M. procerus) (0. T. pyramid 

alis nasi). 

This muscle is wrongly classed as a part of the M. frontahs. 
Comparative anatomy has shown it to have been derived from 
the muscle which lifts the lip. Note that the M. procerus is an 
antagonist of the M. frontalis. 

(b) Orbicular muscle of eye (M. orbicularis oculi) (0. T. orbiculan 

palpebrarum). 
(ba) Palpebral part (pars palpebralis). 



250 LABORATORY MANUAL OF HUMAN ANATOMY 

(baa) Medial palpebral ligament (ligamentum palpe- 

brale mediale). 

(bab) Lateral palpebral raphe (raphe palpebralis lat- 



(bb) Orbital part (pars orbitalis). 
(be) Lacrimal part (pars lacrimalis [Horneri]). 
(c) Corrugator muscle (M. corrugator). 

Note the relation of the muscle to physical or mental effort. 

Muscles of the nose. 
Dilators. 

(a) Transverse part of nasal muscle (pars transversa M. nasalis). 

Note the origin on the back of the nose and insertion into 
skin of nasolabial groove not jugulum alveolare of upper 
canine tooth. It is called the " muscle of sensuality." 

(b) Dilator muscle of nose (M. dilator naris). 

(c) Angular head of quadrate muscle of upper lip (caput angular e 

M. quadrati labii superioris) (0. T. superficial elevator of lip). 

(d) Infraorbital head of quadrate muscle of upper lip (caput infra- 

orbit. M. quadrat, labii superioris) (0. T. deep elevator of 
upper lip). 
Constrictors. 

(a) Alar part of nasal muscle (pars alaris M. nasalis) (0. T. de- 

pressor alae nasi). 

(b) Depressor muscle of septum (M. depressor septi). 

(c) Triangular muscle of nose (M. triangularis nasi). 

Muscles of the lips. 
Dilators of mouth. 
Group 1. 

(a) Muscle of laughing (M. risorius). 

(b) Zygomatic muscle (M. zygomaticus) (muscle of grimace). 
Group 2. 

(c) Quadrate muscle of upper lip (M. quadratus labii superioris). 

(ca) Zygomatic head (caput zygomaticum) (0. T. zygomati- 

cus minor). 

(cb) Infraorbital head (caput infraorbitale) (0. T. levator 

labii superioris). 

(cc) Angular head (caput angular e) (0. T. superficial ele- 

vator of lip, or levator labii superioris alaeque nasi). 
Group 3. 

(d) Canine muscle (M. caninus) (muscle of menacing hate) (0. 

T. levator anguli oris). 

(e) Triangular muscle of mouth (M. triangularis oris) (muscle of 

sadness) (0. T. depressor anguli oris). 
Group 4. 

(/) Quadrate muscle of lower lip (M. quadratus labii inferioris) 

(0. T. depressor labii inferioris). 

(g) Chin muscle (M. mentalis) (muscle of hesitation, doubt, dis- 
dain, disgust). 
Group 5. 

(h) Cheek muscle (M. buccinator) (muscle of suckling; trumpet- 
blower's or glass-blower's muscle). 



DISSECTION OF THE HEAD AND NECK 251 

(ha) Buccopharyngeal fascia (fascia buccopharyngea) . 

In cleaning this muscle avoid injury to the motor 
branch from the N. facialis and the sensory buc- 
cinator nerve from the N. trigeminus. 
Constrictors of mouth. 

(a) Orbicular muscle of mouth (M. orbicularis oris). 

As a muscle of vegetable life it closes the mouth to hinder 
exit of saliva and food, prevents entrance of foreign bodies, 
is prehensile in taking food and liquid, and is active in suction 
and mastication; as a muscle of relational life it closes lips 
partly or completely in physical effort, in articulation of words, 
whistling, playing musical instruments, kissing, etc. 

Note the division into a pars externa and a pars interna. 
The latter is unaffected in cerebral hemiplegia, and the patient 
can still close the mouth, whistle, and speak. Both are affected 
in glosso-labio-laryngeal paralysis, and the patient can no 
longer whistle, retain saliva, or pronounce the letters o and u. 

(b) Compressor muscle of lips (M. compressor labiorum [Kleinii]) 

(0. T. rectus labii of Aeby). 

(c) Incisive muscle of upper lip (M. incisivus labii superioris). 

(d) Incisive muscle of lower lip (M. incisivus labii inferioris). 

The incisive muscles act along with the M. orbicularis oris in 
pointing the mouth : they are sometimes called the " muscles 
of pouting." 
Eeferences. 

1. On the origin of the facial muscles : 

Gegenbaur, C., Lehrbuch der Anatomic des Menschen. 
Ruge, Untersuchungen iiber die Gesichtsmuskulatur der Primaten, 
Leipzig, 1887. 

2. On the muscles as agents of expression : 

Bell, C., Anatomy and Physiology of Expression, 1844. 
Duchenne (of Boulogne), Mecanisme de la physionomie humaine, 

1852. 
Darwin, C., Expression of Emotions in Man and Animals. 

Region of Parotid Gland. 

In the study of the deep cervical fascia the parotideomasse- 
teric fascia (fascia parotideomasseterica) has been observed 
passing upward to become attached to the zygoma. On its sur- 
face the ramus anterior of the N. auricularis magnus was noted. 
The fascia is to be very carefully removed and the parotid gland 
defined. 

Observe the exact position and relations of the parotid gland 
(glandula parotis). Find its excretory duct (ductus parotideus 
[Stenonis] ) and follow it throughout its course. Cut into it and 
pass a probe through into the mouth. Note the position of the 
oral termination of the duct. In relation to the upper border of 
the duct, note the accessory parotid gland (Gl. parotis accesso- 



LABORATORY MAXUAL OF HUMAN ANATOMY 

ria) (O. T. socia parotidis). Follow the retromandibular proc- 
ess of the gland (processus retromandibularis) in behind the 
mandible. How is the pocket in which the parotid gland is con- 
tained separated from that in which the subniaxillarv gland is 
situated? Pick away the parotid gland bit by bit, in order to 
study the blood-vessels and nerves of the region, many of which 
pass directly through the gland-substance. 



Superficial Blood-vessels and Nerves of Face. (Vide Figs. 87. 873, 
and 105.) 

Arteries. 

(a) External carotid (A. carotis externa). 

(aa) Superficial temporal (A. temporalis superficial). 

(aaa) Parotid rami (rami parotidei). 

(aab) Transverse artery of face (A. transversa faciei). 

(aac) Anterior auricular rami (rami auricula res ante- 

riores). 

(aad) Middle temporal artery (A. temporalis media). 

(aae) Zygomatico-orbital artery (A. zygomatico-orbi- 

talis). 

The terminal rami have already been studied in the 
dissection of the scalp. 

(ab) Internal maxillary artery (A. maxittaris interna). 

Its branches cannot yet be seen. 

(ac) External maxillary artery (A. maxiOaris externa) (O. T. 

facial artery). 

(oca) Inferior labial (A. labialis inferior). 
(atA) Superior labial (A. labial is superior), 
(ace) Angular artery (A. angularis). 
Veins. (Cf. Spalteholz, Figs. 487, 488.) 

(a) Posterior facial vein (V. facialis posterior). 

(aa) Superficial temporal vein (V. temporalis superficialis) . 

(ab) Middle temporal vein (V. temporalis media). 

(ac) Anterior auricular veins (Ft?, auriculares anteriores). 

(ad) Posterior parotid veins (Vv. parotideae posteriores). 

(ae) Transverse vein of face (V. transversa faciei). 

(b) Anterior facial vein (V. facialis anterior). 

(ba) Angular vein (V. angularis). 

(baa) Frontal vein (V. frontalis). 

(bab) Supraorbital vein (V. supraorbitalis). 

(bac) Nasofrontal vein (V. nasofrontalis). 

(bad) External nasal veins (Vv. nasales externae). 

(bae) Veins of the lips (Vv. labiates superior et infe- 

rior). 

(baf) Anterior parotid veins (Vv. parotideae ante- 

riores). 

(bag) Masseteric veins (Vv. massetericae) . 

Nerves. Cut away free projecting part of proeessus mastoideus, with saw 






OX OF THE HEAD AXD XECK 



FIG. 105. 



Kami temporales soperficiales of the X. aoriculo- 
temporalis 

Xn. auriculares anteriores 



X. auriculo- 
temporalis 

Branches of 
the X. occipi- 
talis major 



Kami tonporales of the X. facialis 



Bami zygomatici of the X. 

:.. :=.!:- 



4is externus 
- of the N. 
ethmoid- 
tti 



MB '>:- 
cipitalis 
X. auricularis 
posterior 

RMBBBdtoM 



Kami naaales 
ex tern i of the 
X. infraorbi- 

talis 




X. occipitalis minor 
X. auricularis magnns / 



X. hypogloasos / 

Ramos colli 
X. cutaneus colli 



AnsacervicalissoperficialiB 

The distribution of the facial, auriculotemporal. great auricular, greater and 
nerves and their communicatk 

muscle of the eye, the frontal muscle, and the platysma. 
p. S71, Fig. 1314.) 



occipital 



254 LABORATORY MANUAL OF HUMAN ANATOMY 

first and chisel afterwards. Do not injure N. auricularis poste- 
rior. 

(a) Anterior ramus of N. auricularis magnus (ramus anterior N. 

auricularis magni). 

(b) Branches of facial nerve (N. facialis). (Vide Fig. 105.) 

(ba) Parotid plexus (plexus parotideus). 

(bb) Temporal rami (rami temporales). 
(be) Zygomatic rami (rami zygomatici). 

(bd) Buccal rami (rami buccales). 

(be) Ramus of margin of jaw (ramus marginalis mandibulae). 
Examine also 

(bf) Digastric ramus (JR. digastricus) . 

(bfa) Stylohyoid ramus (R. stylohyoideus). 

(bfb) Ramus anastomosing with glossopharyngeal nerve 

(ramus anastomoticus cum N. glossopharyngeo}. 

(c) Branches of trigeminal nerve (N. trigeminus). 

(ca) Branches of ophthalmic nerve (N. ophthalmicus) . 

(caa) Branches of frontal nerve (N. frontalis). 

(caaa) Supraorbital nerve (N. supraorbitalis) . 

(caab) Frontal ramus (ramus frontalis). 

(caac) Supratrochlear nerve (N. supratroch- 

learis). 

(cab) Branches of nasociliary nerve (N. nasociliaris) . 

(caba) One of anterior nasal rami (rami na- 

sales anteriores). 

(cabaa) External nasal ramus (ramus 
nasalis externus). 

(cac) Branches of infratrochlear nerve (N. infratroch- 

learis). 

(caca) Superior palpebral ramus (ramus palpe- 

bralis superior). 

(cacb) Inferior palpebral ramus (ramus palpe- 

bralis inferior). 

(cb) Branches of the maxillary nerve (N. maxillaris) (0. T. 

superior maxillary). 
(cba) Branches of zygomatic nerve (N. zygomaticus). 

(cbaa) Zygomaticotemporal ramus (ramus zy- 

gomaticotemporalis) . 

(cbab) Zygomaticofacial ramus (ramus zygo- 

matico facialis). 
(ebb) Branches of infraorbital nerve (N. infraorbitalis) . 

(cbba) Inferior palpebral rami (rami palpe- 

bralesjnferiores). 

(cbbb) External nasal rami (rami nasales ex- 

terni) . 

(cbbc) Superior labial rami (rami labiales supe- 

rior es ) . 

(cc) Branches of the mandibular nerve (N. mandibularis) (0. T. 

inferior maxillary). 
(cca) Branch of masticatory nerve (N. masticatorius) . 



DISSECTION OF THE HEAD AND NECK 255 

(ccaa) Buccinator nerve (N. buccinatorius) (0. 
T. long buccal). 

(ccb) Auriculotemporal nerve (N. auriculotemporalis) . 

(ccba) Parotid rami (rami parotidei). 

(ccbb) Anastomotic branch of facial nerve 

(ramus anastomoticus cum N. fa- 
cialis). 

(ccbc) Anterior auricular nerves (Nn. auricu- 

lares anteriores). 

(ccbd) Superficial temporal rami (rami tem- 

porales superficiales) . 

(ccc) Mental nerve (N. mentalis). 

(ccca) Mental rami (rami mentales). 

(cccb) Inferior labial rami (rami labiales infe- 

riores), 

Eyelids. (Figs. 106 and 107.) 

Dissect up the M. orbicularis palpebrarum in its entirety 
and reflect it medialward, avoiding injury to the underlying 
vessels and nerves. Study 

(a) Orbital septum (septum orbitale) (0. T. palpebral ligaments). Note 

its attachments. 

(b) Tarsi. 

(ba) Upper tarsus (tarsus superior). 

(bb) Lower tarsus (tarsus inferior). 

How do these differ? 

(c) Tarsal glands (glandulae tarsales [Meibomi]) (0. T. Meibomian 

glands). 

Compare those of the upper with those of the lower lid. Exam- 
ine the orifices with a hand lens along the limbi palpebrales poste- 
riores. Squeeze the lid between the thumb and finger, so as to 
express some of the greasy secretion (sebum palpebrale). 

(d) Lateral palpebral raphe (raphe palpebralis lateralis) (0. T. external 

tarsal ligament). 

Examine its attachments to the os zygomaticum and to the tarsi. 

(e) Medial palpebral ligament (ligamentum palpebrale mediale) (0. T. 

internal tarsal ligament). 

Examine its attachments to the maxilla and to the tarsi. 

(f) Nerves and blood-vessels of the lids. 

These have been enumerated above in connection with the arteries, 
veins, and nerves of the face. 

(g) Tendon of insertion of the M. levator palpebrae superioris. This can 

be exposed by cutting transversely through the upper part of the 
septum orbitale close to the bone and reflecting it downward 
towards the tarsus superior. 

Lacrimal Apparatus (Apparatus lacrimalis). 

Dissect out the upper and lower lacrimal glands (glandula 
lacrimalis superior, inferior). Are any accessory lacrimal 



256 



LABORATORY MANUAL OF HUMAN ANATOMY 



Insertion of the 
tendon of the M. rectus superior 

Fascia muscularis 
Expansion of the ten- 
don of the M. leva- 
tor palpebrae 
superioris 

M. orbicularis oculi , 
Margosupraorbitalis 
Septum orbitale _ 



Fornix conjunctivae- 
superior 

Lens crystal lina-- 
Cornea 

Conjunctiva bulba 
Tarsus inferior 



Conjunctiva palpe-' 
brarum 



Fornix 
conjunctivae inferior 

M. obliquus inferior 

Insertion of the 
tendon of the M. rectus inferior 



FIG. 106. 

Spatium interfasciale (Tenoni) 
,' Fascia bulbi (Tenoni) 

Periorbita 

| M. levator palpebrae superioris 

; I M. rectus superior 

/ Corpus adiposum orbitae 



Foramen opticum 




Processus clinoideus 
anterior. 

'__ A. carotis interna 
. Sinus sphenoidalis 
-- N. opticus 

M. rectus inferior 



Sinus maxillaris 



Paries inferior orbitae 
\ Fascia bulbi (Tenoni) 
Sclera 



The capsule of Tenon (fascia bulbi) and its relation to the tendons of the superior and inferior 
straight muscles (Mm. rectus superior and rectus inferior). (After Toldt, Anat. Atlas, Wien, 1903, 3 Aufl 
p. 907, Fig. 1378.) 



FIG. 107. 



Septum orbitaleC 



Sutura zygomaticomaxillaris 




N. supraorbitalis 

,_.Ramus frontalis 
|_ ..N. supratrochlearis 

- -c -Tarsus superior 

"' f 

_\ Lig. palpebrale mediale 



/"~/ Processes frontalis 
maxiUae 

""* Tarsus inferior 



N. infraorbitalis 



The orbital septum (septum orbitale) and the tarsal cartilages. The skin and orbicular muscle of 
have been removed. ( After Toldt, Anat. Atlas, Wien, 1903, 3 Aufl., p. 909, Fig. 1385. ) 



DISSECTION OF THE HEAD AND NECK 



257 



glands (Gl. lacrimales accessoriae) present? Underneath the 
gland find the minute excretory ducts (ductuli excretorii GL 
lacrimalis). About how many are there ? Where do they open! 
Reflect the ligamentum palpebrale mediale and expose the 
ampulla ductus lacrimalis and the lacrimal sac (saccus lacri- 
malis}. Note its summit (fornix sacci lacrimalis} and the duct 
leading from it down into the nose (ductus nasolacrimalis} . 
(Fig. 108.) 

FIG. 108. 



Papillae lacrimales with the 
puncta lacrimalia 



Plica semilunaris - -- 
conjunctivae 



Saccus lacrimalis 

Crista lacrimalis posterior -~ . :; :, : 

M. obliquus inferior -' ' 
Ductus nasolacrimalis '"' 

Sinus maxillaris "" 




Ampulla ductus lacrimalis 



Lacus lacrimalis (tear lake) 



Fornix sacci lacrimalis 



\---Lig. palpebrale mediale 
( turned back ) 

--(Jrista lacrimalis aiitn-inr 



Caruncula lacrimalis 



Mucous membrane of the nasal cavity 
(laid bare from the outside) 



Lower end of the ductus 
nasolacrimalis 

The tear sac (saccus lacrimalis), the lacrimal canals (ductus lacrimales), and the nasolaerinwl 
duct (ductus nasolacrimalis). Part of the maxilla has been removed. (After Toldt, Anat. Atlas, 
Wien, 1903, 3 Aufl., p. 912, Fig. 1391. ) 

Divide the lids vertically through the middle and turn the 
medial halves of the lids upward and downward respectively. 
Dissect away the conjunctiva at the medial angle of the eye and 
expose the superior tarsal muscle (M. tarsalis superior} and the 
inferior tarsal muscle (M. tarsalis inferior} (0. T. tensor tarsi). 
Note the relation of the saccus lacrimalis to the tarsal muscles 
on one hand and to the medial palpebral ligament on the other. 
What is the action of the tarsal muscles? 

Nose. 

At this stage the nasal bones (ossa nasalia} and cartilages 
(cartilagines nasi} may be conveniently examined. Dissect out 
and study the following: 

(a) Lateral cartilage of nose (cartilago nasi lateral is}. 

(b) Cartilage of septum of nose (cartilago septi misi) (anterior margin ). 

17 



258 



LABORATORY MANUAL OF HUMAN ANATOMY 



(c) Larger alar cartilage (cartilago alaris major). 

(ca) Lateral crus (cms laterale). 

(cb) Medial crus (crus mediale). 

(d) Lesser alar cartilages (cartilagines alares minores). 

Are any sesamoid cartilages present f 

External Ear, or Auricle. (Fig. 109.) 

Though the auricle (auricula) (0. T. pinna) belongs to the 
cranium rather than to the face, it can be most conveniently 
dissected at this stage. 



FIG. 109. 



Helix 
Fossa triangularis 



Crura anthelicis 
Anthelix 



Scapha 



Concha 
auri- 
culae 



Cymba x 
conchae 

Cavum. N 
conchae ? 



Incisura anterior, 
Meatus auditorius externus. 

Tragus - y| 
Incisura intertragica ''I 

Lobulus auriculae 




helicis 



\ 

Sulcus auriculae posterior 



Antitragus 

The external ear (auricula) of a young woman. (After Toldt, Anat. Atlas, Wien, 1903, 

3 Aufl., p. 920, Fig. 1406.) 

Make a careful drawing first of the lateral surface, then of 
the medial surface. Indicate- 
On the lateral surface 

(a) Lobule of auricle (lobulus auriculae). 

(b) Tragus (tragus). 

(ba) Hairs of tragus (tragi). 

(c) Cartilage of antitragus (antitragus) . 

(d) Intertragic notch (incisura intertragica). 

(e) Anterior notch (incisura anterior). 

(f) Concha of auricle (concha auriculae). 

(fa) Cymba of concha (cymba conchae) (" boat of the concha"). 

(fb) Cavity of concha (cavum conchae). 

(g) Coil (helix). 

(ga) Crus of coil (crus helicis). 



DISSECTION OF THE HEAD AND NECK 



259 



(gb) Spine of coil (spina helicis). 

(gc) Tail of coil (cauda helicis). 
(h) Anthelix (anthelix). 

(ha) Crura of anthelix (crura antheUcis). 
(i) Triangular fossa (fossa triangularis). 

(j) Tubercle of auricle (tuberculum auriculae [Darwini]), if present. 
On the medial surface 

(a) Fossa of anthelix (fossa antheUcis). 

(b) Eminence of concha (eminentia conchae). 

(c) Eminence of scapha (eminentia scaphae). 

(d) Eminence of triangular fossa (eminentia fossae triangularis). 

Eemove the skin from the whole auricle, taking care not to 
injure the minute muscles and ligaments beneath. Isolate the 
latter. 

FIG. 110. 



M. auricularis posterior 
M. transversus auriculae 



M. obliquus auriculae 




M. auricularis superior 



M. auricularis anterior (profundus) 
The muscles on the medial surface of the cartilage of the ear. Left ear. (After Toldt, Anat. Atlas, 
Wien, 1903, 3 Aufl., p. 921, Fig. 1413.) 

Muscles. 

(a) Larger muscle of helix (M. helicis major). 

(b) Smaller muscle of helix (M. helicis minor). 

(c) Muscle of tragus (M. tragicus). 

(d) Pyramidal muscle of ear (M. pyramidalis auriculae [Jungi]). 

(e) Muscle of antitragus (M. antitragicus) . 

(f) Transverse muscle of ear (M. transversus auriculae). 

(g) Oblique muscle of auricle (M. obliquus auriculae). 

(h) Muscle of notch of helix (M. incisurae helicis [Santorini]) . 

Ligaments. 

(a) Auricular ligaments (ligamenta auricularia [Valsalvae]). 

(aa) Anterior auricular (Lig. auriculare anterius). 

(ab) Superior auricular (Lig. auriculare superius). 

(ac) Posterior auricular (Lig. auriculare posterius). 



260 LABORATORY MANUAL OF HUMAN ANATOMY 

Cut the auricle off close to the skull ; macerate the cartilages 
and scrape clean. 

Study the following: 

(a) Isthmus of cartilage of ear (isthmus cartilaginis auris). 

(b) Terminal notch of ear (incisura terminates auris). 

(c) Antitragohelicine fissure (fissura antitragohelicina). 

(d) Transverse anthelicine groove (sulcus anthelicis trans versus). 

(e) Groove of sulcus of crus (sulcus cruris helicis). 



TEMPORAL REGION AND RETROMANDIBULAR 

FOSSA. 

Clean away the superficial fascia and expose the deep fascia 
above the zygomatic process. Preserve the arteries, veins, and 
nerves on its surface, and watch especially for blood-vessels and 
nerves perforating the fascia. 

Temporal Fascia. 

The temporal fascia (fascia temporalis) should now be 
studied. What are its attachments? Demonstrate the two lay- 
ers below. What structures perforate the fascia? Trace the 
peripheral distribution of the following : 

(a) Zygomaticotemporal ramus of facial nerve (ramus zygomaticotem- 

poralis N. facialis) (0. T. temporal branch of temporomalar). 

(b) Temporal rami of facial nerve (rami temporales N. facialis). 

(c) Zygomaticofacial ramus of zygomatic nerve (ramus zygomaticofa- 

cialis N. zygomatici). 

Follow the middle temporal artery (A. temporalis media] 
from its origin from the A. temporalis superficialis to the point 
where it pierces the fascia. 

Masseter Muscle. 

The masseter muscle (M. masseter) may now be dissected 
out. Divide the N. facialis below the ear and throw it forward. 
If the other structures superficial to the M. masseter impede the 
dissection, they may also be reflected. Study the form, position, 
origin, and insertion of the muscle. Cut through the fascia tem- 
poralis just above the processus zygomaticus and reflect it 
upward, saving the vessels and nerves which pass through it. 
Cut through the bony arch of the zygoma in front of and behind 
tlie^ origin of the M. masseter. The anterior saw-cut must be 
obliquely made. Throw the bony arch with the M. masseter 



DISSECTION OF THE HEAD AND NECK 261 

lateralward and downward and find the artery (A. masseterica) 
and nerve (N. massetericus, V. 3) passing through the incisura 
mandibulae (0. T. sigmoid notch) to it. Cut through these 
after they have been cleaned and studied, but do not detach the 
M. masseter from its insertion. 

Temporal Muscle. 

The temporal muscle (M. temporalis) may now be examined. 
How are the fibres arranged ! Saw nearly through the coronoid 
process of the mandible, making the cut pass obliquely from the 
middle of the incisura mandibulae downward and forward to the 
junction of the ramus with the basis mandibulae. Complete the 
division with fine forceps. Avoid injury to the N. buccinatorius. 
Reflect the processus coronoideus with the attached M. tempo- 
ralis upward and separate the muscle from the bone. Study the 
anterior and posterior deep temporal nerves (N. temporalis 
profundus anterior posterior] and arteries (A. temporalis 
prof undo, anterior posterior) ; follow the distribution of the 
A. temporalis media; find the point of exit of the ramus zygo- 
maticotemporalis N. zygomatici (0. T. temporal branch of tem- 
poromalar). 

Pterygoid Region. 

Make a cut through the neck of the condyloid process of the 
mandible and another transversely through the ramus man- 
dibulae just above the level of the mandibular foramen (O. T. 
inferior dental foramen). Begin the cuts with the saw and 
complete with bone-forceps. Eemove the incised portion of the 
ramus and dissect away the fat and areolar tissue, so as com- 
pletely to expose the pterygoid muscles and the pterygoman- 
dibular raphe (raphe pterygomandibularis) of the fascia bucco- 
pharyngea. 

Examine carefully the following structures : 

Muscles. (Spalteholz, Figs. 294 and 295.) 

(a) External pterygoid (M. pterygoideus externus). 

(b) Internal pterygoid (M. pterygoideus internus). 

(c) Buccinator muscle (M. buccinator). 

(ca) Buccopharyngeal fascia (fascia buccopharyngea) with its 

raphe pterygomandibularis. 
Arteries. (Vide Spalteholz', Fig. 439.) 

(a) Internal maxillary (.4. maxillaris rntrrna). 
First portion. 

(an) Deep auricular (.1. auricularis profunda}. 
(ab) Anterior tympanic (A. tympanica anterior). 



262 LABORATORY MANUAL OF HUMAN ANATOMY 

(ac) Inferior alveolar (A. alveolaris inferior) (0. T. inferior 

dental). 

(aca) Mylohyoid ramus (ramus mylohyoideus). 
Second portion. 

(ad) Middle meningeal (A. meningea media). 

(ada) Accessory meningeal ramus (ramus meningeus ac- 
cessorius) (0. T. small meningeal). 

(ae) Masseteric (A. masseterica) . 

(af) Posterior and anterior deep temporal (Aa. temporales pos- 

terior et anterior profundae). 

(ag) Pterygoid rami (rami pterygoidei). 

(ah) Buccinator (A. buccinatoria) (0. T. buccal). 
(ai) Posterior superior alveolar (A. alveolaris superior poste- 
rior) (0. T. posterior dental). 
Third portion. 

It cannot be studied at this stage of the dissection. 

Veins. 

These are seldom well enough preserved to be studied in the dissec- 
tion satisfactorily. Atlases illustrating the part and, if possible, 
museum preparations of special venous injections, should be con- 
sulted. 
Tributaries of the posterior facial vein (V. facialis posterior). 

(a) Articular mandibular veins (Vv. articulares mandibulares) . 

(b) Stylomastoid vein (V. stylomastoidea) . 

(c) Pterygoid plexus (plexus pterygoideus). 

(ca) Middle meningeal veins (Vv. meningeae mediae). 

(cb) Deep temporal veins (Vv. temporales profundae). 

(cc) Masseteric veins (Vv. massetericae) . 

(cd) Inferior alveolar vein (V. alveolaris inferior) (0. T. in- 

ferior dental). 

(d) Transverse vein of face (V. transversa faciei). 

Joint of Jaw. 

The jaw-joint (articulatio mandibularis) (0. T. temporomax- 
illary articulation) should now be studied. What bony surfaces 
enter into its formation? 

Examine 



(a) Joint-capsule (capsula articularis) (0. T. capsular ligament). 

(b) Joint-disk (discus articularis) (0. T. interarticular fibrocar- 

tilage). 

(c) Temporomandibular ligament (ligamentum temporomandibu- 

lare) (0. T. external lateral ligament). 

(d) Sphenomandibular ligament (ligamentum sphenomandibulare) 

(0. T. internal lateral ligament). 

(e) Stylomandibular ligament (ligamentum stylomandibulare) (0. 

T. stylomaxillary ligament). 



DISSECTION OF THE HEAD AND NECK 



263 



Nerves of Pterygoid Region. 

To see these well the joint of the jaw should be opened and the 
condyloid process together with the M. pterygoideus externus 
turned forward. Avoid the N. auriculotemporalis. 

(a) Mandibular nerve (N. mandibularis) (0. T. inferior maxillary 

division of the trigeminal nerve), 
(aa) Spinosus nerve (N. spinosus) (0. T. recurrent nerve). 



N. temp. prof. post..-> 

Ramus meningeus_ . . 
N. auriculotetnp.. 

N. facial 
Chorda tympani . . ,!T 



FIG. 111. 



N. temporalis profundus medius 

I 

.N. ophthalmicus 

r .. N. maxillaris 

.N. temporalis profundus anterior 

N". pterygoideus exterior 

X. massetericus 

N. buccinatorius 

.--N. lingualis 




N. alveolaris inferior . . 
N. mylohyoideus. 

Ramus digastricus 



Ramus anast. cum 
N. hypoglosso 

Plexus dentalis 

inferior 
N. mentalis 



i 

Diagram of the N. mandibularis. (From Poirier et Charpy, Trait6 d'Anat. hum., Paris, 1899, 

t. in., 3, p. 824, Fig. 463.) 

(ab) Masticator nerve (N. masticatorius) . 

(aba) Masseteric nerve (N. massetericus). 

(abb) Anterior and posterior deep temporal nerves (Nn. 

temporales profundi anterior et posterior). 

(abc) Buccinator nerve (N. buccinatorius). 

(abd) External pterygoid (N. pterygoideus externus). 

(abe) Internal pterygoid (N. pterygoideus internus). 

(ac) Auriculotemporal nerve (N. auriculotemporalis). 

(aca) Nerve of external auditory meatus (N. meatus au- 

ditorii externi). 

(acaa) Branch to tympanic membrane (ramus 
membranae tympani). 



264 LABORATORY MANUAL OF HUMAN ANATOMY 

The other branches have been already studied, viz. 
(acb) Parotid rami (rami parotidei). 
(ace] Anastomotic with the facial (rami anastomotici 
cum N. faciali). 

(acd) Anterior auricular (Nn. auriculares anteriores). 

(ace) Superficial temporal rami (rami temporales super- 

ficiales ) . 

(ad) Lingual nerve (N. lingualis) (branches studied later). 

(ae) Inferior alveolar nerve (N. alveolaris inferior) (0. T. in- 

ferior dental). 

(aea) Mylohyoid nerve (N. mylohyoideus) . 
Other branches studied later. 

(b) Chorda tympani of N. intermedius. 

(c) Otic gangiion (ganglion oticum). This can be exposed now, but 

can be better studied later. 

Mandibular Canal. 

The mandibular canal (canalis mandibularis) (0. T. inferior 
dental canal) is somewhat difficult to open. 

With Hey's saw, mallet and chisel, and bone-forceps remove 
the outer compact layer of the mandible so as to expose the con- 
tents of the canal. Study the following: 

(a) Inferior alveolar artery (A. alveolaris inferior) (0. T. inferior 

dental). 

(aa) Mylohyoid ramus (ramus mylohyoideus) (not in the canal). 

(ab) Mental artery (A. mentalis). 

(b) Inferior alveolar nerve (N. alveolaris inferior) (0. T. inferior 

dental). 

(ba) Inferior dental plexus (plexus dentalis inferior). 

(baa) Inferior dental rami (rami dentales inferiores). 

(bab) Inferior gingival rami (rami gingivales inferiores). 

(bb) Mylohyoid nerve (N. mylohyoideus) (not in the canal). 
(be) Mental nerve (N. mentalis). 

(bca) Rami to chin (rami mentales). 

(bcb) Rami to lower lip (rami labiales inferiores). 



SUBMAXILLAEY EEGION. 

Draw the tongue forcibly forward and stitch the tip of it to 
the end of the nose. Throw the head backward to the full extent 
and turn slightly to the opposite side. 

Mylohyoid Muscle (M. mylohyoideus) and Subjacent Structures. 

^ The structures which have been dissected, cut superficial to 
this muscle, may now be reflected. Clean the muscle. Study its 
form, position, origin, insertion, action, and innervation. Cut 



DISSECTION OF THE HEAD AND NECK 



265 



FIG. 112. 

Papittaefoliatae Branch to the mucous membrane of the mouth-cavity 
Margo lateralis linguae ft Arcm Vlossopalatinm 

i \ ! Mucous membrane of the isthmus faucium 

\ N. lingualis 



Kami linguales., 
M. ge 



Ramus anastomoticus 
cum n. hypoglosso .... 



Kami linguales ..: 
M. geniohyoidcus 
M. mylohyoideu 

hyogl 



nyionyoiariix 
M. hyoal,** 



Cornu majus ossis hyoidei 




Membrana hyothyreoidea 

Cartilago thyreoidea "' 

M. cricothyreoideus 



Glandula thyreoidea 



TonsiUa palatina 



- M. xti/Iufi/iit ri/nycus 
-N. glossopharyngeus 



X. hj-poglossus 

M. constrictor 
pharyngis mcdius 
N. laryngeus 

superior 
-..Ramus interuus 

Lig. hyothyrcoit}' >nn 
laterals 

Ramus externus 



M. thyreopharyngeus 



M. cricopharyngeus 
N. laryngeus inferior 



> Rami oesophagei 



Kami tmcheale, * 



^-N'. recurrens 



The distribution of the Nn. lingualis, glossopharyngeus, and hypoglossus, and also of the Nn. laryn- 
geus superior and recurrens. The head and neck viscera arc isolated. The upper part of the thyreoid 
gland has been removed. (After Toldt, Anat. Atlas, Wien, 1903, 3 Aufl., p. 880, Fig. 1323.) 



266 



LABORATORY MANUAL OF HUMAN ANATOMY 



through the muscle close to the linea obliqua mandibulae and 
along the median raphe and turn it downward over the hyoid 
bone. Saw through the corpus mandibulae a little lateral from 
the median line. Lift the edge of bone and fasten it by a suture 
to structures above. Avoid injury to the mucous membrane in 
the floor of the mouth. 

Beneath the mylohyoid muscle study carefully the following : 

Muscles. 

(a) Hyoglossus muscle (M. hyoglossus). 

(b) Styloglossus muscle (M. stylo glossus). 

(c) Genioglossus muscle (M. genioglossus}. 

(d) Geniohyoid muscle (M. geniohyoideus) . 



FIG. 113. 



A. maxillaris externa, 
M. massetericus 



M. stylohyoideus 
Gl. parotis 



Gl. submaxillaris 
.M. hyoglossus 

.M. mylohyoideus 

M. digastricus 



A. lingualis 




M. omohyoid. 



V. facialis posterior M . thyreohyoideus 

N. hypoglossusi ^A. thyreoidea superior 

A. carotis externa: ! N. laryngeus superior 

The structures in the submaxillary region. (After Haeckel in Atlas des Topograph. Anat. des 
Mensch. v. Bardeleben, Haeckel, and Frohse-Jena, 1901, Fig. 49.) 

Nerves. (Fig. 112.) 

(a) Lingual nerve (AT. lingualis). 

(aa) Sublingual nerve (N. sublingualis). 

(ab) Lingual rami (rami linguales). 

(b) Hypoglossal nerve (N. hypoglossus). 

(ba) Lingual rami (rami linguales) . 

What muscles are innervated by the N. hypoglossus? 

(c) Submaxillary ganglion (ganglion submaxillare) . 



DISSECTION OF THE HEAD AND NECK 267 

To find this dissect in the interval between the N. lin- 
gualis and the deep part of the glandiila submaxillaris. 
Find 

(ca) Branches communicating with the lingual nerve (rami com- 

municantes cum N. linguali). 

(cb) Submaxillary rami (rami submaxillares) . 
(d) Glossopharyngeal nerve (N. glossopharyngeus) . 

How does it behave as regards the M. hyoglossus ? 
Arteries. 

(a) Lingual artery (A. lingualis}. (Fig. 113.) 
Veins. 

(a) Lingual vein (V. lingualis}. 

(aa) Sublingual vein (V. sublingualis}. 

(ab) Companion veins to hypoglossal nerve (Vv. comites N. 

hypoglossi). 

Salivary Glands. 

(a) Deep part of submaxillary gland (glandula submaxillaris). 

(aa) Submaxillary duct (ductus submaxillaris [Whartoni]). 

(b) Sublingual gland (glandula sublingualis). 

(ba) Larger sublingual duct (ductus sublingualis major) (0. T. 

duct of Bartholin). 

(bb) Smaller sublingual ducts (ductus sublinguales minores) (0. 

T. ducts of Rivini). 

Hyoglossal Muscle (M. hyoglossus). 

Study its form, position, origin, insertion, action, and inner- 
vation. Then detach it from the hyoid bone and reflect it 
upward. Study the structures beneath. 

Arteries. 

(a) Lingual (A. lingualis) in its second and third parts. 

(aa) Dorsal rami of tongue (rami dorsales linguae}. 

(ab) Sublingual artery (A. sublingualis). 

(ac) Deep artery of tongue (A. profunda linguae) (0. T. ranine 

artery). 
Veins. 

(a) Tributaries of lingual vein. 

(aa) Companion veins of lingual artery (Vv. comites A. lin- 
gualis). 

DEEP DISSECTION OF NECK. 
Stylopharyngeus Muscle (M. stylopharyngeus). (Vide Spalteholz, 

Fig. 53I-) 

Remove the calvarium; sponge the floor of the skull-cavity 
with alcohol. Cut through the venter posterior M. digastrici 
near its origin from the incisura mastoidea of the temporal bone, 
and turn it forward and downward. At this point observe the 



268 LABORATORY MANUAL OF HUMAN ANATOMY 

anastomotic ramus connecting the facial with the glossopharyn- 
geal nerve (ramus anastomoticus cum N. glossopharyngeo}. 
From which branch of the N. facialis does it come? Cut through 
the A. carotis externa at a point just inferior to the terminal 
bifurcation into the A. temporalis superficial and the A. maxil- 
]aris interna; cut through also the A. auricularis posterior and 
the A. occipital is at their origins and turn the A. carotis externa 
forward out of the way. Clean the M. stylopharyngeus, avoid- 
ing injury to the N. glossopharyngeus. Study the form, position, 
origin, action, and innervation of the muscle. The insertion can 
be seen best at a later stage of the dissection. 

Internal Carotid Artery (A. carotis interna). 

With bone-forceps cut through the base of the processus sty- 
loideus and reflect it, with the muscles attached to it, downward 
and forward. The vessels and nerves more medially situated 
may now be carefully dissected out of the tough fascia in which 
they lie and traced up to the base of the skull. Secure the 
pharyngeal rami of the N. vagus early; they will be found on 
the lateral surface of the A. carotis interna. Study with especial 
care the interval between the V. jugularis interna and the A. 
carotis interna just beneath the base of the skull. 

What is the level of origin of the A. carotis interna? How 
does it pass into the cranial cavity? Study carefully the compli- 
cated relations of its cervical portion. Why is its proximity to 
the pharynx and palatine tonsil emphasized in the text-books ? 

Smaller Arteries deep in the Neck. (Vide Spalteholz, Figs. 441 and 
442.) 

(a) Ascending pharyngeal artery (A. pharyngea ascendens). 

Note its relations to the A. carotis interna and to the 
pharynx. Study the following branches: 

(aa) Pharyngeal rami (rami pharyngei}. 

(ab) Posterior meningeal (A. meningea posterior}. 

(ac) Inferior tympanic (A. tympanica inferior}. 

(b) Ascending palatine branch of external maxillary (A. palatina as- 

cendens} (0. T. inferior palatine). 

(c) Tonsillar ramus of external maxillary (ramus tonsillaris) (0. T. ton- 

sillitic artery). 

Internal Jugular Vein (V. jugularis interna) and its Tributaries. 

With what cerebral sinus is the internal jugular vein con- 
tinuous? What are the relations of the vein in the jugular fora- 
men? Where is the superior bulb of the jugular vein (bulbus 



DISSECTION OF THE HEAD AND NKCK 269 

venae jugularis superior) situated? What is the relation of this 
vein to the other structures contained within the " vascular 
sheath" of the deep cervical fascia! Observe the entrance of 
the inferior petrosal sinus (sinus petrosus inferior) into the 
superior bulb of the vein. Pass a probe through the sinus from 
the skull cavity into the bulb. Find the pharyngeal plexus 
(plexus pharyngeus) and tributary veins (Vv. pharyngeae). 
The following tributaries of the internal jugular have been 
studied already, but they may now be reviewed with advantage : 

(a) Lingual vein (V. lingualis). 

(b) Superior thyreoid veins (Vv. thyreoideae superior -es). 

(c) Common facial vein (V. facialis communis). 

Slit open the internal jugular vein and observe the valve. 
In what part of the vein is it situated? How many flaps are to 
be seen! 

Hypoglossal Nerve (N. hypoglossus). (Vide Figs. 92 and 112.) 

Divide the V. jugularis interna five centimetres below the 
base of the skull and turn the upper part upward so as to expose 
the N. hypoglossus better as it emerges from the canalis hypo- 
glossi (0. T. anterior condyloid foramen). Note the close con- 
nection of the nerve with the ganglion nodosum of the N. vagus. 
At what point does the N. hypoglossus enter the anterior triangle 
of the neck! Note its relation to the A. occipitalis. Demon- 
strate, if possible, the branches of communication (1) with the 
superior cervical ganglion of the sympathetic, (2) with the gan- 
glion nodosum of the N. vagus, and (3) especially with the Nn. 
cervicales I. and II. What is the significance of the fibres to the 
N. hypoglossus from the cervical nerves! Make a list of (1) the 
muscles supplied by the N. hypoglossus proper and (2) the mus- 
cles supplied by fibres of cervical nerves running in the N. 
hypoglossus. Eeview the branches of the N. hypoglossus already 
studied, viz., (1) ramus descendens, (2) ansa hypoglossi, (3) 
ramus thyreohyoideus, and (4) rami linguales. 

Accessory Nerve (N. accessorius) (O. T. Spinal Accessory). (Vide 

Fig. 92.) 

What is its relation to the N. vagus and N. glossopharyngeus 
in the jugular foramen! Study 

(a) Internal ramus (ramus internus] (0. T. accessory portion). Follow 
it to where it fuses with the N. vagus. 



270 LABORATORY MANUAL OF HUMAN ANATOMY 

(b) External ramus (ramus externus) (0. T. spinal portion). Follow it 
to the sternocleidomastoid muscle. Its peripheral distribution has 
been studied in the neck. 

Vagus Nerve (N. vagus) (O. T. Pneumogastric Nerve). (Vide 

Fig. 92.) 

Study the two ganglia from the cells of which its constituent 
sensory fibres arise : 

(a) Upper or jugular ganglion (ganglion jugulare) (0. T. ganglion of 

the root). 

(b) Lower or knotty ganglion (ganglion nodosum) (0. T. ganglion of the 

trunk). 

In special dissections from the museum, with the aid of 
models and atlases, study the following : 

(a) Meningeal ramus (ramus meningeus) (0. T. recurrent branch). 

(b) Auricular ramus (ramus auricularis) (0. T. Arnold's nerve). 

(c) Anastomotic ramus with glossopharyngeal nerve (ramus anastomoti- 

cus cum N. glossopharyngeo). 

The following branches, already examined in the dissection 
of the side of the neck, may be conveniently reviewed : 

(a) Pharyngeal rami (rami pharyngei). 

(b) Superior laryngeal nerve (N. laryngeus superior}. 

(ba) External ramus (ramus externus). 

(bb) Internal ramus (ramus internus). 

(be) Ramus anastomosing with. inferior laryngeal nerve (ramus 
anastomoticus cum N. laryngeo inferiori). 

(c) Superior cardiac rami (rami cardiaci superior es}. 

(d) Depressor nerve (N. depressor). 

(e) Recurrent nerve (N. recurrens) (0. T. recurrent laryngeal). 

The other branches are studied when the thorax and abdomen 
are dissected. 



Glossopharyngeal Nerve (N. glossopharyngeus). (Vide Fig. 112.) 

Examine its relations in the jugular foramen. Find the two 
ganglia which give origin to those of its fibres that are sensory : 

(a) Upper ganglion (ganglion superius) (0. T. jugular ganglion). 

(b) Lower or petrous ganglion (ganglion petrosum) (0. T. ganglion of 

Andersch). 

Find as many of the branches of the N. glossopharyngeus in 
your own dissection as you can and supplement the study of the 



DISSECTION OF THE HEAD AND NECK 271 

cadaver by that of museum preparations, models, and atlases ; 
include the following : 

(a) Tympanic nerve (N. tympanicus) (0. T. Jacobson's nerve). (Vide 

Spalteholz, Fig. 773.) 
(aa) Tympanic plexus (plexus tympanicus [ Jacobsoni] ) . 

(aaa) Superior caroticotympanic nerve (N. caroticotym- 

panicus superior). 

(aab) Inferior caroticotympanic nerve (N. caroticotym- 

panicus inferior). 

(aac) Tubal ramus (ramus tubae). 

(b) Ramus anastomosing with the auricular branch of the vagus (ramus 

anastomoticus cum ramo auriculari N. vagi). 

(c) Pharyngeal rami (rami pharyngei). 

(d) Stylopharyngeal branch (ramus stylopharyngeus) . 

(e) Tonsillar rami (rami tonsillares) (0. T. tonsillitic branches). 
(/) Lingual rami (rami linguales) (0. T. terminal branches). 

Cervical Part of Sympathetic System (Pars cervicalis S. sympathici). 
Note that the sympathetic trunk (truncus sympathicus) in 
the neck has only three ganglia upon it. (Fig. 92.) 

(a) Superior cervical ganglion (ganglion cervicale superius). 

What evidence is there that it represents four segmental sympa- 
thetic ganglia? 

(b) Middle cervical ganglion (ganglion cervicale medium). 

Why does it probably correspond to two primitive ganglia? 

(c) Inferior cervical ganglion (ganglion cervicale inferius). 

Note that it represents at least two segmental ganglia. 

Study the exact level and relations of each of these ganglia. 
Find the rami communicantes connecting them with the Nn. 
cervicales. 

How much have you made out in your dissection of the fol- 
lowing : 

(a) Jugular nerve (N. jugularis). 

(b) Internal carotid nerve (N. caroticus internus). 

(c) Internal carotid plexus (plexus caroticus internus). 

(d) External carotid nerves (Nn. carotid externi). 

(e) External carotid plexus (plexus caroticus externus). 

(f) Superior thyreoid plexus (plexus thyreoideus superior). 

(g) Lingual plexus (plexus lingualis). 

(h) External maxillary plexus (plexus maxillaris externus). 

(i) Sympathetic root of submaxillary ganglion (radix sympathica gan- 

glii submaxillaris , . 

(,;') Occipital plexus (plexus occipitalis) . 

(k) Posterior auricular plexus (plexus auricularis posterior). 
(1) Superficial temporal plexus (plexus temporal superficialis) . 
(m) Internal maxillary plexus (plexus maxillaris internus). 



272 LABORATORY MANUAL OF HUMAN ANATOMY 

(n) Common carotid plexus (plexus caroticus communis). 

(o) Laryngopharyngeal rarni (rami laryngopharyngei). 

(p) Ascending pharyngeal plexus (plexus pharyngeus ascendens). 

(q) Superior cardiac nerve (N. cardiacus superior). 

(r) Middle cardiac nerve (N. cardiacus medius). 

(s) Subclavian loop (ansa subclavia [ Vieussenii] ) . 

(*) Inferior cardiac nerve (N. cardiacus inferior). 

(u) Subclavian plexus (plexus subclavius). 

(v) Internal mammary plexus (plexus mammarius internus). 

(w) Inferior thyreoid plexus (plexus thyreoideus inferior}. 

(x) Vertebral plexus (plexus vertebralis) . 

Note that all the above, except (a), (i), (o), (g), (r), (s), (t), 
are plexuses about the larger arteries. 

Lateral Straight Muscle of the Head (M. rectus capitis lateralis). 

(Vide Spalteholz, Fig. 304.) 

Clean the muscle; find its origin and its insertion. What is 
its action! What nerve supplies it? Find the ramus anterior of 
the first cervical nerve. How is it related to the M. rectus capitis 
lateralis? How is the first loop of the plexus cervicalis formed? 
Divide the attachment of the M. rectus capitis lateralis close to 
the transverse process of the atlas and turn the muscle upward. 
Sever the origin of the M. obliquus capitis superior. Find the 
nerve to the M. rectus capitis lateralis and follow it to its origin 
from the first cervical nerve (N. suboccipitalis) . 



STRUCTURES IN FOSSA CEANII MEDIA. 

Removal of Dura Mater. 

(a) Cut through the dura mater just lateral from the openings through 

which the III., IV., and V. nerves pass, from the processus cli- 
noideus anterior to the apex pyramidis (0. T. tip of petrous bone). 

(b) Cut through the dura mater from the apex pyramidis backward and 

lateralward along the line of the sinus petrosus superior as far as 
the sulcus sigmoideus. 

(c) Cut through the dura from the processus clinoideus anterior lateral- 

ward and forward along the posterior margin of the ala parva of 
the sphenoid bone to its lateral extremity. 

Lift the dura carefully, keeping the edge of the knife close 
to the membrane, and thus avoid injury to the nerves attached 
to it beneath. 



DISSECTION OF THE HEAD AND NECK 273 

Cavernous Sinus (Sinus cavernosus). (Vide Fig. 114.) 

Where is it situated! What are its boundaries! What im- 
portant structures pass through it? Note the following tribu- 
taries : 

(a) Superior ophthalmic vein ( V. ophthalmica superior) . 

(b) Inferior ophthalmic vein ( V. ophthalmica inferior). 

(c) Sphenoparietal sinus (sinus sphenoparietalis). 

Arteries of the Region. 

(a) Internal carotid artery (A. carotis interna). How does it enter the 

cranial cavity? Study its course. 
(aa) Ophthalmic artery (A. ophthalmica). (Vide Fig. 117.) 

FIG. 114. 

N. oculomotorius 

,.X. trochlearis 
Hypophysis-'llllllllJllp^g^; ^ carotis interna 

X. ophthalmicus 

N. abducens 

maxillaris 
Sinus sphenoidalis-- -* 



Sinus cavernosus 

Histological section passing in a frontal plane through the hypophysis, adult (after Langer). (From 
Poirier et Charpy, Traite d'Anat. hum., Paris, 1901, 2 ed., t. ii. p. 767, Fig. 497. ) 

(b) Middle meningeal artery (A. meningea media). Through what open- 

ing does it enter the middle cranial fossa ? In what portion 
of your dissection did you meet with the origin of this 
artery? Find the following branches: 

(ba) Superficial petrosal ramus (ramus petrosus superficial) . 

(bb) Superior tympanic artery (A. tympanica superior). 

(c) Accessory meningeal ramus (ramus meningeus accessorius) of A. 

meningea media. Look for it entering the skull through the fora- 
men ovale. 

Nerves of the Region. 

(a) Trigeminal nerve (N. trigeminus) (0. T. N. cerebralis V.). 

Observe the exact position of the larger portion (portio 
major) (sensory) and of the smaller portion (portio 
minor) (motor) and their relations to the semilunar gan- 
glion (ganglion semilunare [Gasseri]) (0. T. Gasserian 
ganglion), the cells of which give origin to the sensory 
fibres of the nerve (vide Fig. 115). Read carefully a de- 
scription of the semilunar ganglion in your systematic toxt- 
18 




274 



LABORATORY MANUAL OF HUMAN ANATOMY 



book and compare this with the findings in the cadaver. 
Study the mode of formation of the cavum Meckelii. Ex- 
amine the three great trunks: 

(aa) Ophthalmic nerve (N. ophthalmicus). 

(ab) Maxillary nerve (N. maxillaris) (0. T. superior maxillary). 

FIG. 115. 

N. lacrimalis N. nasociliaris 



Ganglion ciliare 
N. supratrochlearis 
N. ethmoidalis 
N. infratrochlearis 
N. supraorbitalis 



Ganglion sphenopalatinum 

N. canalis pterygoidei (Vidii) 
Plexus caroticus internus 



Ganglion oticum 

i Ganglion semilunare (Gasseri) 



N. zygomaticus 



Kami nasales 
anteriores K 



Kami nasales 
posteriores -/- 3 



N. infra-. 
orbitalis 



N. petrpsus super- 

ficialis major 
; N. petrpsus super- 
ticialis minor 
Chorda tympani 




Kami alveolares 
superiores 



Nn. palatini'' 



Ganglion 
cervicale 
superius 

N. alveolaris 
inferior 

Nn. carotici 
extern! 



. Ganglion 
submaxillare 

-^Plexus caroticus 
externus 



^ Plexus maxillaris 
externus 

A. carotis communis 

Plexus alveolaris inferior 
N. mentalis 

Schematic representation of the N. trigeminus and its connections. (After Toldt, Anat. Atlas, 
Wien, 1903, 3 Aufl., p. 859, Fig. 1298.) 

(ac) Mandibular nerve (N. mandibularis) (0. T. inferior maxil- 
lary). 

Do these trunks arise from the convexity or 
from the concavity of the ganglion? With which 
is the motor root (portio minor) combined? Find 
the following branches of the N. ophthalmicus : 



DISSECTION OF THE HEAD AND NECK 275 

(aca) Frontal nerve (N. frontalis). 

(acb) Lacrimal nerve (N. lacrimalis) . 
(ace) Nasociliary nerve (N. nasociliaris) . 

Through what openings does the N. maxillaris 
leave the skull? Find the meningeal branch (N. 
meningeus (medius)). Through what openings 
does the N. mandibularis leave the skull? Observe 
its relation to the ramus meningeus accessorius of 
the A. meningea media. 

(b) Oculomotor nerve (N. oculomotorius) (0. T. N. cerebralis III.). 

(ba) Superior branch (ramus superior). 

(bb) Inferior branch (ramus inferior). 

(c) Trochlear nerve (N. trochlearis) (0. T. nervus patheticus; N. cere- 

bralis IV.). 

(d) Abducent nerve (N. abducens) (0. T. N. cerebralis VI.). 

(e) Cavernous plexus of sympathetic (plexus cavernosus). 

(f) Larger superficial petrosal nerve (N. petrosus superficialis major). 

(g) Smaller superficial petrosal nerve (N. petrosus superficialis minor). 



ORBIT. 

Removal of Roof of Orbit (Facies superior orbitae). 

Chisel away the thick bone forming the cranial wall above 
the aditus orbitae, but leave unbroken the supraorbital margin 
(mar go supraorbitalis). Remove carefully the whole of the thin 
roof of the orbit (paries superior). With bone-forceps cut away 
that part of the ala parva of the sphenoid bone which forms the 
superior orbital fissure (fissura orbitalis superior) (0. T. sphe- 
noidal fissure). Cut away the processus clinoideus anterior. 
The periosteum of the paries superior is now exposed ; note its 
continuity with the dura mater through the superior orbital 
fissure. Cut through it sagittally midway between the lateral 
and medial walls of the orbit and also transversely near the 
anterior margin of the paries superior. Reflect the two halves 
medialward and lateral ward respectively. Grasp the front of 
the bulbus oculi with forceps, pull it forward, and fasten to the 
nose by means of needle and thread passed through the tunica 
conjunctiva bulbi. Avoid perforation of the eyeball proper. 

Frontal Nerve (N. frontalis). 

Find it lying upon the upper surface of the M. levator pal- 
pebrae superioris. Clean it and the upper surface of the muscle, 
avoiding, in front, the A. supraorbitalis. Study the following 
branches of the N. frontalis : 



276 LABORATORY MANUAL OF HUMAN ANATOMY 

(a) Supraorbital nerve (N. supraorbitalis) . 

(b) Frontal ramus (ramus frontalis). 

(c) Supratrochlear nerve (N. supratrochlearis) . 

The peripheral distribution of these nerves has already been 
studied in the dissection of the face. 

Trochlear Nerve (N. trochlearis) (O. T. Patheticus, or Fourth Cran- 
ial Nerve). 

Carefully remove the fat along the medial wall of the orbit 
until the M. obliquus is found. On its hinder part find the troch- 
lear nerve. Notice the abundance of fat in the orbit (corpus 
adiposum orbitae). 

Lacrimal Nerve (N. lacrimalis). 

Look for it on the lateral wall of the orbit along with the A. 
lacrimalis above the superior margin of the M. rectus lateralis. 
Besides the branches to the lacrimal gland, secure the anasto- 
motic ramus to the zygomatic nerve (ramus anastomoticus cum 
N. zygomatico}. The student will recall having studied the ter- 
minals of the N. lacrimalis (rami palpebrales) in the dissection 
of the upper eyelid. 

Elevator Muscle of Upper Eyelid (M. levator palpebrae superioris). 
Study this muscle carefully. On lifting it, the minute branch 
of the N. oculomotorius innervating it may be seen approaching 
it from the upper surface of the M. rectus superior. 

Lacrimal Glands. 

(a) Superior lacrimal gland (glandula lacrimalis superior}. 

(b) Inferior lacrimal gland (glandula lacrimalis inferior). 

(c) Accessory lacrimal glands [inconstant] (glandulae lacrimales ac- 

cessoriae). 

(d) Excretory ductules (ductuli excretorii [Gl. lacrimalis]). 

Fascia of Eyeball (Fascia bulbi [Tenoni]) (O. T. Capsule of Tenon). 
Divide the N. frontalis in the middle of the orbit and reflect 
the stumps. Cut through the M. levator superioris in the middle 
and reflect. With the point of a sharp narrow-bladed knife 
make an oblique valvular opening into the eyeball at the junction 
of cornea and sclera. Introduce the tip of a blow-pipe and inflate 
the eyeball with air. On withdrawal, the valve-like character 
of the opening prevents the escape of the air. Pick up with 




DISSECTION OF THE HEAD AND NECK 277 

forceps the upper part of the loose bursa-like tissue (fascia bulbi 
[Tenoni]) (O. T. capsule of Tenon) at the back of the eyeball 
and remove a bit with scissors. Through the opening thus made 
introduce the handle of the knife, and explore the interfascial 
space (spatium inter -fas dale [Tenoni]). Determine the extent 
of the space. What is the relation of the tendons of the eye- 
muscles to the fascia bulbi? 

Superior Straight and Superior Oblique Muscles of Eye (M. rectus 
superior; M. obliquus superior). 

Establish the form, position, origin, insertion, innervation, 
and action of each. Examine carefully the pulley (trochlea) 
through which the tendon of the superior oblique muscle runs. 

FIG. 116. 



M. leva tor palpebral superior 
M. obliquus superior 



Vasa ophthalmie'u 
M. rectus lateralis 

N. ophthalmicus 
M. rectus inferior 

Sinus maxillaris 

Frontal section through the right orbit behind the bulbus oculi. Posterior surface. (From Gegenbaur, 
Lehrb. der Anat. des Mensch., Leipzig, 1899, 7 Aufl., Bd. ii. p. 589, Fig. 715.) 

Optic Nerve and Neighborhood. (Vide Fig. 116.) 

Cut through the M. rectus superior and reflect the ends. 
Beneath its posterior part find the ramus superior of the N. 
oculomotorius. Remove the fat over the optic nerve and study 
the following structures : 

(a) Optic nerve (N. opticus). 

(b) Nasociliary nerve (N. nasociliaris) (0. T. nasal nerve). 

(ba) Long root of ciliary ganglion (radix longa ganglii ciliaris). 

(bb) Long ciliary nerves (Nn. ciliares longi). 

(be) Posterior ethmoidal nerve (N. ethmoidalis posterior). 

(bd) Anterior ethmoidal nerve (N. ethmoidalis anterior). 

(be) Infratrochlear nerve (N. infratrochlearis). 

(bea) Superior palpebral branch (ramus palpebralis supe- 
rior). 




278 



LABORATORY MANUAL OF HUMAN ANATOMY 



(beb) Inferior palpebral branch (ramus palpebralis infe- 
rior) (already studied in dissection of the face). 
(bf) Anterior nasal rami (rami nasales anteriores) (to be studied 

further when the nasal cavity is dissected). 
(c) Ciliary ganglion (ganglion ciliare) (0. T. lenticular or ophthalmic 

ganglion ) . 
(ca) Short ciliary nerves (Nn. ciliares breves). 

Try to find also the sympathetic roots of the ciliary gan- 
glion (radices sympathicae ganglii ciliaris). 

Blood-vessels of Orbit. 

Arteries. 

(a) Ophthalmic artery (A. ophthalmica). 

(aa) Central artery of retina (A. centralis retinae). 

(ab) Lacrimal artery (A. lacrimalis). 

(aba) Lateral palpebral arteries (Aa. palpebrales lat- 
er ales}. 

(ac) Muscular rami (rami musculares). 



FIG. 117. 



N. nasociliaris 



N. frontalis . 



N. ethmoidalis anterior- 



N. frontalis j 

X 
X. lacrimalis 




-a\. ophthalmica 
A. supraorbitalis 

A. ethmoidalis anterior 
\. lacrimalis 



A. ophthalmica 



Relation of the branches of the ophthalmic artery to the nerves. (After Poirier et Charpy, Trait6 
d'Anat. hum., Paris, 1901, 2 ed., t. ii. p. 698, Fig. 103.) 

(ad) Short posterior ciliary arteries (Aa. ciliares posteriores 

breves). 

(ae) Long posterior ciliary arteries (Aa. ciliares posteriores 

longae). 

(af) Anterior ciliary arteries (Aa. ciliares anteriores). 

(a fa) Episcleral arteries (Aa. episclerales) . 

(afb) Anterior conjunctival arteries (Aa. conjunctivales 

anteriores). 



DISSECTION OF THE HEAD AND NECK 279 

(ag) Supraorbital artery (A. supraorbitalis) . 
(ah) Posterior ethnioidal artery (A. ethmoidalis posterior), 
(ai) Anterior ethmoidal artery (A. ethmoidalis anterior), 
(aj) Medial palpebral arteries (Aa. palpebrales mediates). Note 
especially 

(aja) Superior tarsal arch (arcus tarseus superior). 

(ajb) Inferior tarsal arch (arcus tarseus inferior). 

(ajc) Posterior conjunctival arteries (Aa. conjuncti- t 

vales posterior es] . 
(ak) Dorsal artery of nose (A. dorsalis nasi) (0. T. nasal 

branch). 
(al) Frontal artery (A. frontalis). 

Veins. (Tributaries of the sinus cavernosus.) 

(a) Superior ophthalmic vein (V. ophthalmica superior). 

(aa) Naso frontal vein (V. naso frontalis) . 

(ab) Anterior and posterior ethmoidal veins (Vv. ethmoidales 

anterior et posterior). 

(ac) Lacrimal vein (V. lacrimalis). 

(ad) Muscular veins (Vv. muscular es). 

(b) Inferior ophthalmic vein (V. ophthalmica inferior). 

(c) Central vein of retina (V. centralis retinae). 

The following veins of the bulbus oculi and of the eyelids are 
drained partly by the V. ophthalmica superior, partly by the V. 
ophthalmica inferior: 

(d) Vortex veins (Vv. vorticosae). 

(e) Posterior ciliary veins (Vv. ciliares posteriores) . 

(f) Anterior ciliary veins (Vv. ciliares anteriores). 

(g) Episcleral veins (Vv. episclerales) . 
(h) Palpebral veins (Vv. palpebrales). 

(i) Anterior and posterior conjunctival veins (Vv. conjunctivales pos- 
teriores et anteriores). 

Other Straight Muscles of Eyeball. 

The M. rectus superior has already been studied and re- 
flected. Examine the origin, insertion, position, action, and 
innervation of each of the following muscles : 

(a) Medial straight muscle (M. rectus medialis) (0. T. rectus internus). 

(b) Inferior straight muscle (M. rectus inferior). 

(c) Lateral straight muscle (M. rectus lateralis) (0. T. external rectus). 

(ca) Lacertus of lateral straight muscle (lacertus musculi recti 
lateralis). 

Divide the N. opticus close to the foramen opticum and turn 
the eyeball forward. Examine the attachment of the eye-muscles 
behind. What is meant by the common tendinous ring of Zinn 
(annulus tendineus communis [Zinni]) (O. T. ligament of 
Zinn)? 



280 



LABORATORY MANUAL OF HUMAN ANATOMY 



How are the muscles of the eye (musculi oculi} inserted into 
the eyeball (bulbus oculi} ? 

Oculomotor and Abducent Nerves (Nn. oculomotorius et abducens). 
Study these two nerves through their course. 

(a) Oculomotor nerve (N. oculomotorius) (0. T. third nerve). 

(aa) Superior ramus (ramus superior). 

(ab) Inferior ramus (ramus inferior). 

(aba) Short root of ciliary ganglion (radix brevis ganglii 
ciliaris) (0. T. motor root of lenticular ganglion). 

(b) Abducent nerve (N. abducens) (0. T. sixth nerve). What muscle 

does it innervate? 

FIG. 118. 

M. rect. sup.. .M. lev. palp. sup. 
A. ophthal. i : M. obliq. sup. 



N. lacrimalis ^ 

N. frontalis -J 

N. trochlearis - -*. 

N. ophthal. sup. -j| 
N. abducens 

M. rect. lat.- 




N. opticus. 

- Annulus tend. com. 
[Zinni] 

. rect. med. 



M. rect. inf/ 



; N nasociliaris 

'Ram. inf. N. oculomotorii 



Schema of the annulus tendineus communis [Zinni] and its relations to the nerves of the orbit. (From 
Poirier et Charpy, Trait6 d'Anat. hum., Paris, 1899, t. iii., 3, p. 794, Fig. 440.) 

Compare the arrangement of the various nerves in the supe- 
rior orbital fissure (fissura orbitalis superior) (0. T. sphenoidal 
fissure) with that of the nerves in the sinus cavernosus. What 
are the principal differences ? 

Inferior Oblique Muscle of Eye (M. obliquus inferior). 

Replace the eyeball in its natural position. Evert lower eye- 
lid, and dissect off conjunctiva in the region of the fornix con- 
junctivae inferior. Find the inferior oblique muscle and clean 
it. Study its origin, insertion, action, and innervation. 



DISSECTION OF THE HEAD AND NK< K 



281 



FIG. 119. 



Ram. sup. N. oculomotorii 
N. maxillaris : 
N. abducens 
N. oculomotorius 




X. mandibularis i 

N. ophthalmicus i 
N. maxillaris 

G. sphenopalat. 



: ; Nn. ciliar. brev. N. infraoi i* 

Branch to M. obi. inf. 
G. ciliare 

Distribution of the N. oculomotorius (after Hirschfeld). (From Poirier et Charpy, Traits d'Anat. hum. 
Paris, 1899, t. iii., 3, p. 796, Fig. 441.) 



FIG. 120. 



Upper border of the tarsus superior 
Cut edge of the fascia muscularis 



Spatium interfasciale (Tenoni) 



Fascia bulbi (Tenoni) 



Tendon of the M. obliquus 
superior 

M. reotus medialis- 
N/opticus 




M. levator palpebrae superioris (turned 
forward) 



^.Glandula lacrimalis 



Fascia musrularis 



of the M. n-ctus snj.rri.ir 
jit'tcr inssiii- through the fascia 
hull.i 



M. reel i is superior 
M. Tvrtuslateralis 



The capsule of Tenon (fascia bulbi) and its relation t.. the superior reel us miMcle of the right eye. Seen 
from above. (After Toldt, Ami. Atlas, Wi(>n, 1903, 3 Aufl., p. 907, Fig. 1379.) 



282 LABORATOKY MANUAL OF HUMAN ANATOMY 

Fascia of Bulb (Fascia bulbi [Tenoni]) (O. T. Capsule of Tenon). 

Compare the fascia in the eye before you with a description 
of it in some good systematic text-book. Open the interfascial 
space (spatium interfasciale [Tenoni]). (Compare Lockwood, 
J. Anat. and Physiol., Lond., vol. xx., 1885.) What is meant 
by the " fat body of the orbit" (corpus adiposum orbitae) 1 

Zygomatic Nerve (N. zygomaticus) (O. T. Temporomalar Nerve). 
Find this nerve entering the orbit through the inferior orbital 
fissure (fissura orbitalis inferior) (0. T. sphenomaxillary fis- 
sure). Follow its two branches : 

(a) Zygomaticotemporal ramus (ramus zygomaticotemporalis) (0. T. 

temporal branch of temporomalar). 

(b) Zygomaticofacial ramus (ramus zygomaticofacialis} (0. T. malar 

branch of temporomalar). 

Recall where the terminals of these two rami were previously 
met with in the dissection. 



REGION IN FRONT OF CERVICAL SPINE (PRE VER- 
TEBRAL REGION). 

Place the dissection upside down, the cut margin of the cra- 
nium resting on the table. Cut through the A. carotis communis, 
V. jugularis interna, N. vagus and truncus sympathicus on each 
side at level of neck of first rib. Displace trachea, oesophagus, 
large vessels and nerves forward, separating them from the 
front of the spine. Complete the separation to the base of the 
skull, but be careful not to injure adjacent structures. Make a 
transverse cut through the thick periosteum on the pars basilaris 
of the occipital bone, the knife passing between the pharynx in 
front and the prevertebral muscles behind. Rest the inside of 
the base of the skull (basis cranii interna) upon a wooden block, 
apply a chisel in the line of the cut through the periosteum of 
the basis cranii externa (between pharynx and prevertebral mus- 
cles), and with a wooden mallet cut through the pars basilaris 
of occipital bone. 

Turn the head first on one side and then on the other, in 
each instance making a saw-cut through the side of the cranium 
from a point one centimetre behind the processus mastoideus, 
obliquely forward and medialward, to a point just behind the 
jugular foramen. Next place the dissection in such a position 



DISSECTION OF THE HEAD AND NECK 283 

that the basis cranii interim looks upward; on each side com- 
plete the division of the base of the skull by chiselling through 
the solid interval still left, i.e., from the lateral extremity of 
the chisel-cut through the pars basilaris backward upon the 
medial side of the jugular foramen to the medial end of the 
saw-cut. 

FIG. 121. 

Pars basilaris 



Process^ ^ofdCMf \--"l*li >MHBWiW\i" /" M " rectus Capitis latt ' mlis 

Processm, ... m air ! i -^^^v posterior) 

culum anteriux utlanti* 
M. longus capitis 

. levator scapulae 
!M_ _M. longus colli 



ossis occipitalis Pars prtrosa 
ossis tempo rains 




M. scalenus medius 



M. scalenus anterior 

~.M. scalenus posterior 

Scalenus-space 



costae II. 



The deep muscles of the front of the neck. (After Toldt, Anat. Atlas, Wk-n, 1900, 3 Aufl., p. 294, 



Fig 



The forepart of the skull (with the pharynx and great vessels 
and nerves) is now to be separated from the hind part (with 
the cervical spine). The N. hypoglossus is cut through close to 
the base of the skull, but should not be separated from the gan- 
glion of the N. vagus. Wrap the pharynx and forepart of the 



284 LABORATORY MANUAL OF HUMAN ANATOMY 

skull in moist carbolized cloths and oil-cloth and lay aside for 
subsequent dissection. 

In the posterior part of the dissection work out the following : 

Muscles. 

(a) Lateral straight muscle of head (M. rectus capitis lateralis). 

This has been studied before in the deep dissection of the neck. 

(b) Anterior straight muscle of head (M. rectus capitis anterior) (O. 

T. rectus capitis anticus minor). 

(c) Long muscle of head (M. longus capitis) (0. T. rectus capitis an- 

ticus major). 

(d) Long muscle of neck (M. longus colli). 

Determine the form, position, origin, insertion, action, and innerva- 
tion of each of the above muscles. Review the attachments of the Mm. 
scaleni. Then cut away entirely the prevertebral and scalene muscles 
and study from in front 

(e) Intertransverse muscles (Mm. intertransversarii) . 

(ea) Anterior (Mm. intertransversarii anteriores). 

(eb) Posterior (Mm. intertransversarii posteriores) . 

Nerves. 

Eight cervical nerves (Nn. cervicales I.~VIII.). 

(a) First cervical nerve (N. cervicalis I.). 

(aa) Anterior ramus (ramus anterior) (0. T. anterior primary 

division). 

(ab) Posterior ramus (ramus posterior, or N. suboccipitalis) 

(0. T. posterior primary division). 

(b) Second cervical nerve (N. cervicalis II.). 

(ba) Anterior ramus (ramus anterior) (0. T. anterior primary 

division ) . 

(bb) Posterior ramus (ramus posterior) (O. T. posterior pri- 

mary division). 

(bba) Medial ramus (ramus medialis, or N. occipitalis 

major). 

(bbb) Lateral ramus (ramus lateralis). 

(c) Third to eighth cervical nerves (Nn. cervicales III -VIII.). 

(ca) Anterior rami (rami anteriores) (0. T. anterior primary 

divisions). 

(cb) Posterior rami (rami posteriores) (0. T. posterior pri- 

mary divisions). 
Blood-vessels. 

Remove the intertransverse muscles (Mm. intertransversarii), M. 
rectus capitis lateralis, M. obliquus capitis superior, and M. obliquus 
capitis inferior. With bone-forceps cut away the anterior tubercles 
and costal processes of the transverse processes of the third, fourth, 
fifth, and sixth cervical vertebrae. Study 

(a) Vertebral artery (A. vertebralis) . 

(aa) Spinal rami (rami spinales). 

Find the plexus vertebralis of the sympathetic around 
the artery. 

(b) Vertebral vein (V. vertebralis). 



DISSECTION OF THE HEAD AND NECK 



Ramus muscularis for the Mm. recti 
capitis, anterior and lateralis 
and the M. longus capitis 

M. rectus capitis lateral iv 



Ramus muscularis for the Mm. longus capitis. 
and longus colli \ 



Anastomosing branch to the ramus descendens. 
X. hypoglossi 

X. occipitalis minor. 

Anastomosing branch to the ramus 
externus X. accessorii 

X. auricularis magnus 

X T . cutaneus colli. 



Nn. supraclaviculares-x;^". 

N. phrenicus ' - 
N. dorsalis scapulae 
N. suprascapularis. - 



FIG. 122. 

A. i-arotix hit< run 



X. axillari 
X. radialis 



X. musculo-- 
cutaneus 



X. mediam 

X. ulnaris 

X. cutaneus anti-.' 
brachii medialis 
Xn. snbscapulares''''' ^ 
X. thoracalis loogttB 



M. rectus capitis anterior 

X. caroticus internus 



/X. cervicalis I. 
Ramus communicans 

X. cervicalis II. 



Ganglion cervicale superius 
Xn. cen-icales III., IV. 

Ramus communicans 
A. vertebral! s 



$ ^^Truncus sympathicus 

Xn. cervicalesV., VI., VII. 



^Ganglion cervicale 

medium 
,X. cervicalis VIII. 

Gangfipn cervicale 
inferius 

V , - Ganglion thoracale I. 

E X. thoracalis I. 

-. ^Plexus vertebralis 



Plexus subclavius 



\AlM sulx'lavia 

(Vieuss-iiii i 




M. serratus anterior Xn. thoracal.^ M. scalcnus mcdius 

anteriores 



The cervical and brachial plexuses. (After Toldt, Anat. Atlas, Wien, liOS. :i Aufl., p. sic,. Kitf. 1'Jiv) 



286 



LABORATORY MANUAL OF HUMAN ANATOMY 



LIGAMENTS OF VERTEBRAL COLUMN AND SKULL 
(LIGAMENTA COLUMNAE VERTEBRALIS 
ET CRANII). 

Remove all muscles from the spinal column and posterior 
part of the bones of the skull and study the following : 

(a) Joints of the lower five cervical vertebrae. 

(aa) Intervertebral fibrocartilages (fibrocartilagines interverte- 

b rales), 
(aaa) Fibrous ring (annulus ftbrosus). 

FIG. 123. 



Pars basilaris os. occip. 



Lig. apicisdentis | 

Mem. atlanto-occipitalis ant. 
Bursa 



Caps, artic. of the articulatio 
atlanto-epistrophica 

Lig. atlanto-epistrophicum ant. .... . 



Lig. longitudinale anterius .*- 




Lig. longitudinale posterius 
__. Supra-odontoid synovial cavity 
Memb. tectoria 
.... Lig. cruc. atlantis (superior limb) 

Lig. trans, atlantis 

. Synovial cavity of the lig. 
trans, atlan. 

Bursa 

Lig. cruc. atlan. (inferior limb) 



Epistropheus 



VAVy^ 

Sagittal section through the articulationes atlanto-occipitalis and atlanto-epistrophica. 
.From Pomer et Charpy, Traite" d'Anat. hum., Paris, 1899, 2 ed., t. i. p. 814, Fig. 799.) 



(aab) Pulp-like nucleus (nucleus pulposus). What is the 
relation of this to the chorda dorsalis of the 
embryo ? 

(ab) Yellow ligaments (ligamenta ftava) (0. T. ligamenta sub- 
flava). 



DISSECTION OF THE HEAD AND NECK 



287 



(ac) Joint-capsules (capsulae articulares) . 

(ad) Intertransverse ligaments (ligamenta intertransversaria) . 

(ae) Interspinous ligaments (ligamenta interspinalia) . 

(af) Supraspinous ligament (ligamentum supraspinale) . Here 

called the ligamentum nuchae. 

(ag) Anterior longitudinal ligament (Lig. longitudinale anterius) 

(0. T. anterior common ligament). 

(ah) Posterior longitudinal ligament (Lig. longitudinale posterius) 
(0. T. posterior common ligament). 

(b) Joint between atlas and occipital bone (articulatio atlanto-o'ccipitalis) . 

What kind of joint is it? Study 

(ba) Joint-capsules (capsulae articulares). 

(bb) Anterior atlanto-occipital membrane (membrana atlanto- 

occipitalis anterior). 

(be) Posterior atlanto-occipital membrane (membrana atlanto- 
occipitalis posterior). 

(c) Joint between atlas and epistropheus or axis (articulatio atlanto- 

epistrophica) . 
(ca) Joint-capsules (capsulae articulares). 



FIG. 124. 




Pars basilaris ossis occipitalis 

| 

. cruciatum atlantis 
Lig. alare. 

f 

Lig. transversum atlantis 



Lig. cruciatum atlantis 



Lig. cruciatum atlantis posterior view. (From Poirier et Charpy, Traittf d'Anat. 
hum., Paris, 1899, 2 ed., t. i. p. 818, Fig. 802.) 



Before studying further, cut away the posterior arches of the atlas and 
epistropheus with heavy bone-forceps. With a saw, cut through the 
occipital bone on each side from a point behind the processus jugularis 
and the condylus occipitalis into the foramen magnum, so that the whole 
squama occipitalis may be removed. Remove the dura mater and study 
the following: 

(cb) Tectorial membrane ("roof-membrane") (membrana tecto- 
ria) (0. T. posterior occipito-axial ligament). 



288 LABORATORY MANUAL OF HUMAN ANATOMY 

Detach this from the epistropheus and reflect it upward. 
Study the following : 

(cc) Cruciform ligament of atlas (ligamentum cruciatum atlantis). 

Observe its two parts (cf. Spalteholz, vol. i., Fig. 
218) : 

(cca) Transverse ligament (ligamentum transversum at- 

lantis). 

(ccb) Vertical part. 

Detach the vertical part, reflect it downward, 
and study 

(cd) Alar ligaments (ligamenta alaria) (0. T. odontoid or check 

ligaments). 

(ce) Ligament of apex of tooth (ligamentum apicis dentis) (0. T. 

suspensory ligament). How is this ligament related to the 
chorda dorsalis? 

Name from before backward the ligaments of the articulatio 
atlanto-occipitalis and articulatio atlanto-epistrophica. (Cf. 
Spalteholz, p. 169.) 

What movements can occur at these joints! What muscles 
are concerned in such movements ? How is excessive movement 
in any direction checked ? 



MOUTH AND FAUCES. 

Eeturning to the forepart of the skull and neck, the dissector 
now studies the following, comparing his findings in the cadaver 
with illustrations in atlases and descriptions in his systematic 
text-book. 

Cavity of Mouth (Cavum or is). 

General. 

(a) Cheek (bucca). 

(aa) Fat body of cheek (corpus adiposum buccae). 

(b) Entrance to mouth (vestibulum oris). This is bounded in front 

and laterally by lips and cheeks, behind by teeth and gums. 

(c) Mouth cavity proper (cavum qris proprium). This is internal to 

the teeth. 

(d) Mouth slit or oral fissure (rima oris). 

(e) Lips of mouth (labia oris). 

(ea) Upper lip (labium superius). 

(eb) Lower lip (labium inferius). 

(f) Junction of lips (commissura labiorum). 

(g) Angles of mouth (angulus oris). 
(h) Palate (palatum). 

(ha) Hard palate (palatum durum). 

(hb) Soft palate (palatum molle). 

(he) Middle ridge of palate (raphe palati). 



DISSECTION OF THE HEAD AND NECK 



289 



FIG. 125. 



Septum cartilagineum 



Septum mobile nasi 



Cavum nasi 

Palatum durum 

Tonsilla pharyngea 



, Ostium pharyngeum tubae 

^.Fornix pharyngis 
^^ ,,.Pars nasalis pharyngis 
Isthmus faucium 



Velum 
---- palatinum 



Epistropheus 
Pare oralis pharyngis 



Lymphoglandula- 

M. mylohyoideus' 



_Pars laryngea pharyngis 



Vestibulum laryngis .... 

Prominentia laryngea 

Cavum laryngis 




Trachea - 
Isthmus glandulae thyreoideae 



Venae thyreoideae inferiores -^ 
Vena anonyma sinistra 

Thymus. J 

Cavum pericardii-^ 



Auricula cordis 
dextra 



Corpus tfrrui j 
Pericardium 

Sulcus coronarius cordis 

Atrium cordis dextrum 



Arteria anonyma 

-Aorta ascendent 



If Oesophagus (pars thoracalis) 



ordisdextrum \ \ * Lymp hoglandulae bronchioles 
Cavum pcricardii ; p er l car( n um 
Atrium cordis sinistrum 

The viscera of the head and neck and their connections in the thorax. (After Toldt, 
Anat. Atlas, Wien, 1900, 2 Aufl., p. 395, Fig. 636. ) 



19 



29Q LABORATORY MANUAL OF HUMAN ANATOMY 

Mucous Membrane of Mouth (Tunica mucosa oris). 

(a) Check-cord of upper lip (frenulum labii superioris). 

(b) Check-cord of lower lip (frenulum labii inferioris). 

(c) Gum (gingiva). 

(d) Sublingual caruncle (caruncula sublingualis). 

(e) Sublingual fold (plica sublingualis} . 

(/) Transverse palatine folds (plicae palatinae transversae). 
(g) Incisor papilla (papilla incisiva). 
Glands of Mouth (Glandulae oris). 

(a) Labial glands (glandulae labiales). 

(b) Buccal glands (glandulae buccales). 

(c) Molar glands (glandulae molares). 

(d) Palatine glands (glandulae palatinae). 

(e) Lingual glands (glandulae linguales). 

(f) Anterior lingual gland (glandula lingualis anterior [Blandini, 

Nuhni]) (0. T. gland of Nuhn). 

(g) Sublingual gland (glandula sublingualis). 

(ga) Larger sublingual duct (ductus sublingualis major). 

(gb) Smaller sublingual ducts (ductus sublinguales minores). 
(h) Submaxillary gland (glandula submaxillaris) . 

(ha) Submaxillary duct (ductus submaxillaris [Whartoni]) (0. 

T. Wharton's duct). 
(i) Parotid gland (glandula parotis). 

(ia) Retromandibular process (processus retromandibularis) (0. 

T. socia parotidis). 

(ib) Accessory parotid gland (glandula parotis accessoria). 
(ic) Parotid duct (ductus parotideus [Stenonis]) (0. T. Steno's 

duct). 

(j) Mixed mouth secretions (saliva). 
Teeth (Denies). 

(a) Superior dental arch (arcus dentalis superior). 

(b) Inferior dental arch (arcus dentalis inferior). 

How many teeth does each arch contain ? 

(c) Incisor teeth (denies incisivi). 

(d) Canine teeth (dentes canini). 

(e) Premolar teeth (dentes praemolares) (0. T. bicuspids). 
(/) Molar teeth (dentes molares). 

(fa) Late tooth (dens serotinus) (0. T. wisdom tooth). 
How many of these teeth are present in your cadaver? What is 
meant by deciduous teeth (dentes decidui) and permanent teeth (dentes 
permanent es) ? 
Tongue. (Vide Figs. 125 and 137.) 

(a) Dorsum of tongue (dorsum linguae). 

What is a " coated tongue" ? 

(b) Root of tongue (radix linguae). 

(c) Inferior surface (fades inferior [linguae]). 

(d) Lateral margin (margo lateralis [linguae]). 

(e) Apex or tip of tongue (apex linguae). 

(f) Mucous membrane (tunica mucosa linguae). 

The muscles of the tongue and the details of the mucous mem- 
brane will be studied later. 



DISSECTION OF THE HEAD AND NECK 291 

Fauces. 

(a) Isthmus of fauces (isthmus faucium). 

(b) Palatine curtain (velum palatinum). 

(c) Uvula (uvula palatinum). This little body is often cut off by 

the surgeon if it becomes so relaxed and lengthened that it causes 
continued tickling of the throat. 

(d) Palatine arches (arcus palatini). 

(da) Glossopalatine arch (arcus glossopalatinus) (0. T. ante- 

rior pillar of fauces). 

(db) Pharyngopalatine arch (arcus pharyngopalatinus) (0. T. 

posterior pillar of fauces). 

(e) Tubopalatine or salpingopalatine fold (plica salpingopalatina) . 

This cannot be seen well until later, when the pharynx is opened 
from behind. 

(/) Palatine tonsil (tonsilla palatina) (0. T. ordinary tonsil). This 
will be studied later. 

The muscles of the palate and fauces will be studied with 
those of the pharynx. 



PHARYNX. 

Place the chin of the cadaver on a block with the pharynx 
hanging downward, its posterior surface turned towards dis- 
sector. Distend the cavity of the pharynx with cotton or tow. 

Buccopharyngeal Fascia (Fascia buccopharyngea). 

(a) Pterygomandibular raphe (raphe pterygomandibularis) (0. T. ptery- 
gomaxillary ligament). This will be seen as a dense cord between 
the hamulus pterygoideus and the posterior end of the crista buc- 
cinatoria [mandibulae] ) . 

Observe that the part of the fascia in front of (a) covers the M. 
buccinatorius, that behind (a) covers the muscles of the pharynx. 

Muscular Tunic of Pharynx (Tunica muscularis pharyngis). 

Study the form, position, origin, insertion, action, and inner- 
vation of each of the following muscles : 

(a) Inferior constrictor muscle of pharynx (M. constrictor pharyngis 

inferior). 

(aa) Thyreopharyngeal muscle (M. thyreopharyngeus). 

(ab) Cricopharyngeal muscle (M. cricopharyngeus) . 

(b) Middle constrictor muscle of pharynx (M. constrictor pharyngis 

medius). 

(ba) Chondropharyngeal muscle (M. chondropharyngeus) (from 

cornu minus os. hyoid.). 

(bb) Ceratopharyngeal muscle (M. ceratopharyngeus) (from 

cornu majus os. hyoid.). 



292 



LABORATORY MANUAL OF HUMAN ANATOMY 



Between (a) and (b) observe the A. laryngea inferior and the ramus 
internus of the N. laryngeus superior perforating the membrana hyo- 
thyreoidea. 



FIG. 126. 

Processus pterygoideus (lamina medialis} 



M. tensor veil mlatini 



Raphe pterygo- 
mandibularis 



M. buccinator 



M. hyoglossus 
Tendo M. digastrici 




Lamina membranacea 
tubae auditivae 

_M. levator veli palatini 
~; Fascia pharyngobasilaris 



M. pterygo- 
pharyngeus 

- M. bucco- 
pharyngeus 



M. mylo- 
pharyngeus 



M. con- 
strictor 
pharyngis 
superior 



M. myloh 



Os hyoideum 
Membrana hyothyreoidea/ 



M. glosso- 

pharyngeus j 
- M. stylopharyngeus 

M. styloglossus 

M. chondro-1 

pharyngeus M. constrictor 

V pharyngis 
-M. cerato- medius 

pharyngeus j 
-Accessory muscle-bundle 
springing from the tendon of 
the M. stylohyoideus 



Cartilago thyreoidea 



Tendinous streak J 
M. circothyreoideus. 



.M. thyreo- ] 
pharyngeus 



M. crico- 
pharyngeus 



M. constrictor 

pharyngis 

inferior 



Cartilago cricoidea 
Oesophagus 



"^""'n'- 'TUfth*' 

The muscles of the pharynx The ramus of the mandible and the styloid process of the temporal bone 
)een removed. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 417, Fig. 682.) 

Next cut through the M. pterygoideus internus at its middle and 
s two ends; avoid injury to M. tensor veli palatini just medial 

(c) Superior constrictor muscle of pharynx (M. constrictor pharyngis 
superior}. 



DISSECTION OF THE HEAD AND NECK 293 

(ca) Pterygopharyngeal muscle (M. pterygopharyngeus). 

(cb) Buccopharyngeal muscle (M. buccopharyngeus). 

(cc) Mylopharyngeal muscle (M. mylopharyngeus) . 

(cd) Glossopharyngeal muscle (M. glossopharyngeus). 
Between (b) and (c) observe the M. stylopharyngeus and the N. 

glossopharyngeus. Observe the interval between the uppermost con- 
strictor muscle and the base of the skull; here a thickened portion of 
the tela submucosa pharyngis (0. T. pharyngeal aponeurosis), called 
the pharyngobasilar fascia (fascia pharyngobasilaris) , is visible. The 
semilunar space where the muscle is absent is sometimes called the 
" sinus of Morgagni." In the lateral part of this on each side the M. 
levator veli palatini, the M. tensor veli palatini, and the cartilage of 
the Eustachian tube (cartilago tubae auditivae) can be seen; these 
structures will be dissected out carefully later. 

Cavity of Pharynx (Cavum pharyngis). 

Open the pharynx from behind by a vertical incision in the 
median line of its posterior wall along its whole length. Divide 
the fascia pharyngobasilaris close to the basis cranii externa 
on each side, carrying the knife from the median line lateralward 
as far as the cartilage of the Eustachian tube. Remove the stuff- 
ing of tow or cotton. Sponge the tunica mucosa clean and study 
the cavum pharyngis. With what cavities or tubes does the 
cavity of the pharynx communicate? Explore the " vault of 
the pharynx " (fornix pharyngis). How is the cavity of the 
pharynx bounded ? What very important structures are related 
to its lateral walls? Where does the pharynx end and the 
oesophagus begin? Observe the three parts of the cavum 
pharyngis (see Fig. 125) : 

(a) Nasal part (pars nasalis) (0. T. nasopharynx). 

(b) Oral part (pars oralis) (0. T. oral pharynx). 

(c) Laryngeal part (pars laryngea) (0. T. laryngopharynx). 
Find - 

(d) Pharyngeal opening of Eustachian tube (ostium pharyngeum 

tubae auditivae}. 

(da) Anterior lip (labium anterius). 

(db) Posterior lip (labium posterius). This is sometimes called 

the tubal projection (torus tubarius), owing to the 
rounded eminence it forms. 

(dc) Salpingopharyngeal fold (plica salpingopharyngea) . 

It extends downward from the lower end of the labium 
posterins. 

(e) Pharyngeal recess of Rosenmiiller (recessus pharyngeus [Rosen- 

mulleri]) (0. T. recessus infundibuliformis). 

(/) Pharyngeal tonsil (tonsilla pharyngea) (0. T. Luschka's tonsil). 
It is enlargement of this tonsil that constitutes the " post- 
adenoids" so often met with in children. 
(fa) Tonsillar crypts (fossulae tonsillares). 



294 



LABORATORY MANUAL OF HUMAN ANATOMY 



(g) Pharyngeal bursa (bursa pharyngea}. 

Look into the nasal cavity behind and observe the septum of 
the nose (septum nasi) separating the two choanae. The fol- 
lowing are visible : 

(1) Nasopharyngeal meatus (meatus nasopharyngeus) . 

(2) Inferior meatus of nose (meatus nasi inferior). 

(3) Middle meatus of nose (meatus nasi medius). 

(4) Inferior turbinated bone (concha nasalis inferior). 

(5) Middle turbinated bone (concha nasalis media). 



FIG. 127. 

Fornix pharyngis 



Sinus sphenoidalis___ 



Concha nasalis media 



Meatus nasi medius 



Concha nasalis 

inferior 



Meatus nasi inferior 

i 

Palatum durum - 

Jlp 
Sulcus nasalis posterior^ 

Plica salpingopalatina 
Projection due to the M. leva tor veli 

palatini s 

Velum palatinum 

Paries lateralis pharyngis 




Fibrocartilago basalis 

Tonsilla pharyngea 

Bursa pharyngea (Var.) 



Fascia pharyngobasilaris 

Recessus pharyngeus 
_-( Rosen mu ell eri) 

Torus tubarius 

Ostium pharyngeum 
tubae auditivae 

Membrana atlanto- 

occipitalis anterior 

Plica salpingo- 

pharyngea 



.Paries dorsalis 
pharyngis 

fascia praeverte- 
fyralis 

_. JLrcus pharyngo- 
palatinus 



Medial aspect of right nasopharynx. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 420, Fig. 686.) 



The posterior surface of the velum palatinum, the uvula, and 
the arcus pharyngopalatinus are to be examined; they have 
already been seen in front. Find the following : 
(h) Pharyngo-epiglottic fold (plica pharyngo-epiglottica) . 
(i) Aryepiglottic fold (plica aryepiglottica). 
(j) Opening into larynx (aditus laryngis) (vide Fig. 95). 

Observe the epiglottis guarding the opening. 
(k) Piriform recess (recessus piriformis) (0. T. sinus pyriformis). 

Foreign bodies often become lodged in this pocket. 
(ka) Fold of laryngeal nerve (plica nervi laryngei). Look for 
it in anterior part of recessus piriformis. 

Soft Palate (Palatum molle). (Vide Figs. 127 and 130.) 

The mucous membrane of this structure has already been 
viewed from the mouth; it is now to be studied also from the 
pharyngeal side. 



DISSECTION OF THE HEAD AND NECK 295 

Make the velum palatinum tense by means of a hook and 
dissect the tunica mucosa off both its surfaces (oral and pharyn- 
geal) and also off the arcus glossopalatinus and the arcus phar- 
yngopalatinus. Observe the distribution of the glandulae pala- 
tinae. 

Study the form, position, origin, insertion, action, and inner- 
vation of each of the following : 

Muscles of the Palate and Fauces (Mm. palati et faucium). (Cf. Spalte- 
holz, Figs. 551 and 552.) 

(a) Glossopalatine muscle (M. glossopalatinus) (0. T. palatoglossus). 

(b) Pharyngopalatine muscle (M. pharyngopalatinus) (0. T. palato- 

pharyngeus). 

(Observe here the salpingopharyngeal muscle (M. salpingo- 
pharyngeus) ; it is really a part of the tunica muscularis 
pharyngis.) 

(c) Muscle of uvula (M. uvulae) (0. T. azygos uvulae). 

Now remove the wall of the pharynx between the Eustachian 
tube (tuba auditiva) above and the upper border of the M. con- 
strictor pharyngis superior below. Study 

(d) Levator muscle of palatine curtain (M. levator veil palatini) (0. 

T. levator palati). 

(e) Tensor muscle of palatine curtain (M. tensor veil palatini} (0. T. 

tensor palati). Note especially the nerve supply of this muscle; 
also the bursa M. tensoris veli palatini. What is meant by the 
" palatal aponeurosis" ? 

Study also 

Arteries. 

(a) Ascending palatine artery (A. palatina ascendens) (0. T. inferior 

palatine). Of what is it a branch? Where have you met it 
before ? 

(b) Pharyngeal rami of ascending pharyngeal artery (rami pharyngei 

A. pharyngeae ascendentis) (0. T. palatine branch of ascending 
pharyngeal). 

(c) Descending palatine artery from internal maxillary artery (A. 

palatina descendens). 

Veins. 

(a) Pharyngeal veins (Vv. pharyngeae), from pharyngeal plexus 

(plexus pharyngeus) to V. jugularis interna. 

(b) Palatine vein (V. palatina), corresponding to A. palatina ascendens 

and emptying into V. f acialis anterior. 

Nerves. (Figs. 12S and 132.) 

(a) Branches of N. accessorius (through the rami pharyngei N. vagi) 

to the M. levator palati, M. uvulae, M. pharyngopalatinus, and 
M. glossopalatinus. 

(b) Nerve of the palatine tensor (N. tensoris palatini), from motor 

part of N. trigeminus (through ganglion oticum) to the M. 
tensor veli palatini. 



296 LABORATORY MANUAL OF HUMAN ANATOMY 

(c) Palatine nerves (Nn. palatini), from the N. trigeminus through the 
ganglion sphenopalatinum. 

(ca) Middle palatine nerve (N. palatinus medius) (0. T. exter- 

nal palatine). 

(cb) Posterior palatine nerve (TV. palatinus posterior}. 

Palatine Tonsils (Tonsillae palatinae). (Vide Spalteholz, Figs. 545- 

548.) 

Observe the exact situation of the palatine tonsil on each side. 
How is it related to neighboring structures? What especial 
danger might be run in lancing a peritonsillar abscess ! 

(a) Tonsillar crypts or fossulae (fossulae tonsillares). Are any of them 

filled with yellowish- white plugs? 

(b) Tonsillar sinus (sinus tonsillaris). Is it completely filled by the 

tonsil or is there a fossa supratonsillarisf Note the plica triangu- 
laris. 

How is the tonsil supplied with blood? How is the tonsil 
related to the cervical lymph-glands? 

Auditory or Eustachian Tube (Tuba auditiva [Eustachii]). 

Of its two parts, one is lateral and bony (pars ossea tubae 
auditivae), the other medial and cartilaginous (pars cartilaginea 
tubae auditivae). The cartilaginous part is now studied. Its 
pharyngeal opening (ostium pharyngeum tubae auditivae) has 
already been examined. Pass a bristle or probe into it and ascer- 
tain the direction of the tuba auditiva. What is the position of 
the tuba as regards the M. levator veli palatini and the M. tensor 
veli palatini ? 

Dissect the mucous membrane cautiously away around the 
pharyngeal opening of the tube and examine the constitution of 
the cartilaginous portion. 

The cartilage of the Eustachian tube (cartilago tubae audi- 
tivae) consists of two laminae, one medial (lamina cartilaginis 
medialis) and one lateral (lamina cartilaginis lateralis). (Cf. 
Spalteholz, Fig. 552.) Where cartilage is lacking, a strong mem- 
branous layer (lamina membranacea) takes its place. Open the 
tuba auditiva and examine the mucous membrane (tunica mu- 
cosa). Are there any glands (glandulae mucosae) or solitary 
lymph-nodules (noduli lympJiatici tubarii) visible! Observe the 
trumpet-shape of the canal. 

From which of the inner branchial pockets of the embryo do 
the Eustachian tube and cavity of the middle ear arise? 



DISSECTION OF THE HEAD AND NECK 297 

CAROTID AND INFRAORBITAL CANALS (CANALIS 
CAROTICUS ET CANALIS INFRAORBITALIS). 

Carotid Canal (Canalis caroticus). 

Remove the inferior wall of the carotid canal with strong 
forceps. Do not disturb the position of the Eustachian tube. 
Inside the carotid canal study the following : 

(a) Internal carotid artery (A. carotis internet). (Cf. Spalteholz, Fig. 

442.) 

(aa) Caroticotympanic ramus (ramus caroticotympanicus) (0. T. 
tympanic branch). 

(b) Venous plexus of internal carotid (plexus venosus caroticus internus). 

(c) Internal carotid nerve of sympathetic system (N. caroticus internus). 

(Cf. Spalteholz, Figs. 773 and 779.) 
(ca) Internal carotid plexus (plexus caroticus internus). 

(caa) Deep petrosal nerve (N. petrosus profundus) (0. T. 
large, deep petrosal nerve), which runs to the 
pterygoid canal (0. T. Vidian canal) and unites 
with the N. petrosus superficialis major to form 
the nerve of the pterygoid canal (N. canalis ptery- 
goidei [Vidii]) (0. T. Vidian nerve). 

Infraorbital Canal (Canalis inf raorbitalis) . 

Remove the M. temporalis and the upper head of the M. 
pterygoideus externus ; saw through the squama temporalis and 
the ala magna oss. sphenoidalis, beginning on the cut margin of 
the skull just above the meatus acusticus externus and passing 
obliquely downward and forward towards the medial end of 
the fissura orbitalis superior (0. T. sphenoidal fissure). The 
saw-cut should enter the fissura orbitalis superior just lateral 
from the foramen rotundum. Make a second saw-cut from 
the cut margin of the cranial wall, just above the anterior 
margin of the ala magna oss. sphenoidalis, downward into the 
fissura orbitalis superior, to meet the first saw-cut. Remove 
the bone thus freed and with bone-forceps remove what remains 
of the ala magna lateral from the foramen rotundum, keeping 
intact, however, the entire bony margin of this aperture. Next 
open the canalis inf raorbitalis with bone-forceps (or chisel if 
necessary). Study the following: 

(a) Maxillary nerve (N. maxillaris) (0. T. superior maxillary). (Fig. 
115, p. 274.) 

Trace it from the ganglion semilunare [Gasseri] to its 
termination. 



298 LABORATORY MANUAL OF HUMAN ANATOMY 

(aa) Middle meningeal nerve (N. meningeus [medius]) (0. T. 

recurrent). 

This has been studied already within the cranium. 

(ab) Zygomatic nerve (N. zygomaticus) (0. T. orbital or temporo- 

malar). 

Already studied, with its two rami, in the orbit, 
.(ac) Sphenopalatine nerves (Nn. sphenopalatini) , going to the 
ganglion sphenopalatinum. 

(ad) Superior alveolar nerves (Nn. alveolares superiores). 

(ada) Posterior superior alveolar rami (rami alveolares 
superiores posteriores) (0. T. posterior superior 
dental). 

(ae) Infraorbital nerve (TV. infraorbitalis). 

(aea [also adb]) Middle superior alveolar ramus (ramus 
alveolaris superior medius) (0. T. mid- 
dle superior dental). 

(aeb [also adc]) Anterior superior alveolar rami (rami 
alveola? 3 s superiores anteriores) (0. 
T. anterior superior dental). 
How is the superior dental plexus (plexus den- 
dentalis superior) formed? Find 

(1) Superior dental rami (rami dent ales supe- 

riores). 

(2) Superior gingival rami (rami gingivales 

superiores). 

The other terminal rami of the infraorbital nerve have been 
studied in the dissection of the face. 
(b) Infraorbital artery (A. infraorbitalis). 

Its origin has already been studied. Examine its course 
and 

(ba) Anterior superior alveolar arteries (Aa. alveolares superiores 
anteriores) (0. T. anterior superior dental). 



SAGITTAL SECTION OF FOREPART OF HEAD NEAR 
MEDIAN PLANE. 

Remove the mandible, with the tongue and larynx, by making 
a cut backward from the angle of the mouth through the cheek, 
the raphe pterygomandibularis, and the lateral wall of the phar- 
ynx. Cut through also the vessels and nerves still connecting 
the pharynx with the skull. Wrap the larynx and tongue in 
moist cloth for subsequent dissection. 

Make a sagittal saw-cut through the forepart of the skull 
just lateral from the septum nasi; if the septum is not vertical, 
but deviates somewhat to one side, make the section close to the 
concave side of the septum. Before sawing, cut through the 
cartilaginous part of the nose as far as the nasal bone with a 



DISSECTION OF THE HEAD AND NECK 



299 



knife and cut through the soft palate in the same plane. Then 
saw through the bone from behind forward; the saw passes 
through the hard palate and the roof of the nose. 



FIG. 128. 

Ramus anastomoticus cum N. spinoso Portio minor -v 



Cms longum incudis 



Membrana tyrnpani^^ 



Chorda tympani 



N. petrosus superficial minor 
N. tensoris tympari 
M. tensor tympani \ 



N. trigemini 



Portio major j 

N. masticatorius 




Manubrium mallei 

N. facialis X 
N. auriculotemporalis 



Ganglion oticum 
X. tensoris veli palatini 

N. pterygoideus 
internus 

-N. pterygoideus 

externus 
^..V. tensor veli palatini 



Ramus anastomoti- 

cus cum N. auriculo- 

temporali 



Ramus anastomoticus 
cum chorda tympani 
N. lingualis 



Plexus caroticus internus with its 
offshoots, the plexus maxillaris 

internus and meningeus , 

A. meningea media ! i_ , _ ,, ^-*^^, , 

N. alveolans infenor 
t. pterygoideus internus 
I. mylohyoideus 

The otic ganglion and its connections seen from the medial side. (After Toldt, Anat. Atlas, 
Wien, 1903, 3 Aufl., p. 867, Fig. 1307.) 



Radix sympathica of the Ganglion oticum 



Otic Ganglion (Ganglion oticum) (O. T. Ganglion of Arnold). (Fig. 
128.) 

Place the sagittal cut surface upward ; detach the M. levator 
veli palatini at its origin and reflect it downward. Remove very 
cautiously the pars cartilaginea tubae auditivae; the otic gan- 
glion lies just beneath, between it and the N. mandibularis. A 
useful guide is the nerve to the M. pterygoideus internus ; follow 
it upward and backward to the otic ganglion. Find the fol- 
lowing i ' roots ' ' : 

(a) Short root: from the N. mandibularis. 

(b) Long root: lesser superficial petrosal nerve (N. petrosus super- 

ficialis minor) ; probably contains motor fibres from N. facialis 
and sensory fibres from N. glossopharyngeus. 

(c) Ganglionic or sympathetic root (radix sympathica} : from plexus 

in middle mening-eal artery. 
Branches of Distribution. 

(a) Nerve of tensor muscle of palatine curtain (N. tensoris veli pala- 
tini). 



300 



LABORATORY MANUAL OF HUMAN ANATOMY 



(b) Nerve of tensor muscle of tympanum (N. tensoris tympani). 
Connecting Branches. 

(a) With spinous nerve of mandibular nerve (ramus anastomoticus cum 

N. spinoso). 

(b) With auriculotemporal nerve of mandibular nerve (ramus anasto- 

moticus cum N. auriculotemporali) . 

(c) With chorda tympani (ramus anastomoticus cum chorda tympani). 



Cavity of Nose (Cavum nasi). (Vide Figs. 130 and 131.) 
Study- 

(a) Septum of nose (septum nasi). 

Remove the mucous membrane and examine 

(aa) Cartilaginous septum (septum cartilagineum ) . 

(ab) Membranous septum (septum membranaceum) . 

Remove the cartilage and bones of septum piecemeal, 
avoiding injury to the mucous membrane of the opposite 
side of the septum. Find 



N. nasopalatinus (Scarpae) 



FIG. 129. 

Nn. olfactorii (medial row) 



;y--Bulbus olfactorius 



.Ramus nasalis 
internus (N. 

etnmoid - ant -) 



[Kami nasales 

f mediales 




Medial branches of the olfactory nerve (after Hirschfeld). (From Poirier et Charpy, Traite" d'Anat. 
hum., Paris, 1897, t. iii., 3, p. 775, Fig. 418.) 

(ac) Nerves of the septum nasi. 

(aca) Olfactory nerves (Nn. olfactorii). 

(acb) Medial superior posterior nasal rami (rami nasales 

posterior es superior es mediales). 
(acba) Nasopalatine nerve (N. nasopalatinus 
[Scarpae]) (0. T. nerve of Cotun- 



DISSECTION OF THE HEAD AND NECK 



301 



nius), from the sphenopalatine gan- 
glion. 

(ace) Medial nasal rami of internal nasal rami of ante- 
rior nasal rami of N. nasociliaris (rami nasales 
mediates) (O. T. septal branch of nasal nerve). 
(ad) Arteries going to the septum. 

Of what are they branches? 

Now cut through the tunica mucosa septi, with scissors, along the 
roof of the nasal cavity and reflect it; the nasopalatine nerve and 
medial nasal rami are to be preserved for further examination. 



FIG. 130. 



Concha nasalis media 
Concha nasalis superior : 
Meatus nasi superior 
Apertura sinus sphenoidalis | i 



Meatus nasi medius 



Recessus sphenoethmoidalis 
Hypophysis 



Sinus sphenoidalis 
Fomix pharyngis 



Synchondrosis 

spheno-occipi 

talis 

Sulcus nasalis 
posterior 



Sinus frontalis 



Agger nasi 



Plica salpingo- 

palatina 
Torus tubarius- 



Ostium pharyngeum 
tubae auditivae 

Levator prominence -^ 

Plica salpingo- ^ 
pharyngea 

Velum palatinum 




Atrium meatus 
nasi medii 

Cartilage nasi 
lateralis 
Limen nasi 



Vestibu- 
lum nasi 



Cartilago 
alaris 
major 
(Cms 
mediale) 
Remnant of the 
cartilage of the 
lateral wall 

Concha nasalis 
inferior 

Meatus nasi inferior 



Medial aspect of the left wall of the nasal cavity (After Toldt, Anat. Atlas, Wien, 1903, 

3Aufl., p 944, Fig 1473.) 



(b) Anterior apertures (nares). 

(c) Posterior apertures (choanae). 

(d) Vestibule of nose (vestibulum nasi). 

(da) Hairs in vestibule (vibrissae). 

(e) Threshold of nose (limen nasi). 

(f) Olfactory sulcus (sulcus olfactorius) . 

(g) Conchae (0. T. turbinated bones). 

(ga) Superior nasal concha (concha nasalis superior) (0. T. supe- 

rior turbinated bone). 

(gb) Middle nasal concha (concha nasalis media) (0. T. middle 

turbinated bone). 



302 



LABORATORY MANUAL OF HUMAN ANATOMY 



(*) 



(gc) Inferior nasal concha (concha nasalis inferior) (0. T. infe- 
rior turbinated bone). 

Is a highest nasal concha (concha nasalis suprema [San- 
torini]) present? Observe the mucous membrane of the 
nose (membrana mucosa nasi). Over the concha there is 
much erectile tissue (plexus cavernosi concharum). What 
is the spheno-ethmoidal recess (recessus spheno-ethmoid- 
alis) ? 

The agger ("elevation") of the nose (agger nasi) (0. T. rudiment 
of anterior turbinal). 



FIG. 131. 



Infundibulum ethmoidale 
with the apertura sinus maxillaris 
Opening of the labyrinthus ethrnoidalis \ 

Recessus sphenoethmoidalis 
Apertura sinus sphenoidalis > 

Concha nasalis superior 

Sinus 
sphenoidalis 

Meatus 

nasi superior- 
Concha nasali 
media (partly 
removed) 
Sulcus 
nasalis ' 
posterior 

Torus tubarius 

Ostium pharyn- 
geum tubae 
auditivae 
Levator prominence 



Bulla ethmoidalis 



Velum palatinum 




<J__ Sinus frontalis 



__ Apertura sinus frontalis 

Cut edge of the 
concha nasalis media 



^_ Hiatus semilunaris 



Meatus 
- nasi medius 



Limen nasi 



Vestibulum 
nasi 



_.Ala nasi 



Concha nasalis 
inferior 

Channel leading 

down from the 

mouth of the 

ductus naso- 

lacrimalis 

Meatus nasi inferior 

Medial aspect of the left wall of the nasal cavity, after removal of the greater part of the middle 
and the anterior part of the superior turbinated bones (concha nasalis media and concha nasalis 
superior). (After Toldt, Anat. Atlas, Wien, 1903, 3 Aufl., p. 944, Fig. 1474.) 

(i) Meatuses of the nose (meatus nasi). 

(ia) Superior meatus (meatus nasi superior), 
(ib) Middle meatus (meatus nasi medius). 

(iba) " Entrance-hall" of middle meatus (atrium meatus 

medii). 

(ic) Inferior meatus (meatus nasi inferior), 
(id) Common meatus (meatus nasi communis). 
(ie) Nasopharyngeal meatus (meatus nasopharyngeus) . 
(j) Regions of the nose. 

(ja) Respiratory region (regio respiratoria) . 
(jb) Olfactory region (regio olfactoria). 

What is the extent of the latter? 
(fc) Glands of nose. 



DISSECTION OF THE HEAD AND NECK 303 

(ka) Olfactory glands (Gl. olfactoriae) . 
(kb) Nasal glands (GL nasales). 

Force the concha media upward and backward and examine 
(1) Ethmoidal infundibulum (infundibulum ethmoidale). 

(la) Semilunar opening (hiatus semilunaris) . 
(m) Ethmoidal "bubble" (bulla ethmoidalis) . 

Where are the ethmoidal cells (cellulae ethmoidales) and how do 
they communicate with the nose? 
(n) Sinuses near nose (sinus paranasales) . 

(na) Maxillary sinus (sinus maxillaris [Highmori]) (0. T. antrum 
of Highmore). 

Open this by removing its lateral wall. How does it 
communicate with the nose? 
(nb) Sphenoidal sinus (sinus sphenoidalis) . 
(nc) Frontal sinus (sinus front alis). 
(o) Nerves of lateral wall of nose. (Fig. 132.) 
(oa) Olfactory nerves (Nn. olfactorii). 

(ob) Anterior nasal rami of ethmoidal nerve (rami nasales ante- 
rior es}. 
(oba) Internal nasal rami (rami nasales interni). 

(obaa) Lateral nasal rami (rami nasales later- 
ales). 

(obb) External nasal ramus (ramus nasalis externus). 
(oc) From ganglion sphenopalatinum. 

(oca) Lateral superior posterior nasal rami (rami nasales 

posterior es superior es laterales). 
(ocb) [Lateral] inferior posterior nasal rami (rami nasales 

posterior es inferiores [laterales]). 
(od) Internal nasal rami (rami nasales interni), from anterior 

superior alveolar rami of N. infraorbitalis). 
(p) Arteries of lateral wall of nose. 

What is the arterial supply here? Work out the large branches. 



SPHENOPALATINE GANGLION (GANGLION SPHENO- 
PALATINUM) (0. T. MECKEL'S GANGLION). 

The lateral posterior nasal rami (superior and inferior) have 
already been found; follow them back to the pterygopalatin'e 
canal (canalis pterygopalatinus) (0. T. posterior palatine 
canal) ; open this canal thoroughout its length and follow the 
palatine nerves (Nn. palatini) upward to the sphenopalatine 
ganglion which lies in the pterygopalatine fossa (fossa pterygo- 
palatina) (0. T. sphenomaxillary fossa). In connection with 
the ganglion sphenopalatinum study the following: 

(a) Orbital rami (rami orbitales). 

(b) Nerve of the pterygoid canal, or Vidian nerve (N. canalis pterygoidei 

[Vidii]). 



304 



LABORATORY MANUAL OF HUMAN ANATOMY 



(ba) Larger superficial petrosal nerve (N. petrosus superficialis 

major). 

(bb) Deep petrosal nerve (N. petrosus profundus) (0. T. great 

deep petrosal branch of carotid plexus). 

To display (&), cut away with bone-forceps the sphenoidal 
process (processus sphenoidalis) of the palate bone and carefully 
open the pterygoid or Vidian canal, which passes through the root 
of the pterygoid process of the sphenoid bone. 



FIG. 132. 



Rami lat. Nn. olf. 
Kami iiasales ant. N. eth. ant. 



N. nasopalatinus 
! N. maxillaris 




Gang, sphenopalat. 

N. canal. 
.^S pterygoid. 



N. petrosus 
profund. 

Kami 
pharyngei 



N. palat. post. 
N. palat. med. 
N. palat. ant. 



Ramus to palatal 
mucous mem- 
brane 



Lateral branches of the olfactory nerves (after Hirschfeld). (From Poirier et Charpy, Traits 
d'Anat. hum., Paris. 1899,, t. in., 3, p. 774, Fig. 417.) 

(c) Nasal rami (rami nasales). (Vide Fig. 132.) 

(ca) Lateral superior posterior nasal rami (rami nasales poste- 

riores superiores laterales). 

(cb) Medial superior posterior nasal rami (rami nasales poste- 

rior es superiores mediales). 

(cba) Nasopalatine nerve of Scarpa (N. nasopalatinus 
[Scarpae]). 

(cc) [Lateral] inferior posterior nasal rami (rami nasales poste- 

riores inferiores [laterales]). 

These have been previously examined in their peripheral dis- 
tribution. 

(d) Palatine nerves (Nn. palatini). 

(da) Anterior palatine nerve (N. palatinus anterior). 

Trace it to its terminals in the tunica mucosa of the hard 
palate. 



DISSECTION OF THE HEAD AND NECK 305 

(db) Middle palatine nerve (N. palatinus medius) (0. T. external 

palatine). 
(do) Posterior palatine nerve (N. palatinus posterior}. 

Near this note the tendinous expansion of the M. tensor 

veli palatini. 

Trace the N. nasopalatinus [Scarpae] also back to its origin. 
A better view still of the pterygopalatine fossa will be obtained 
if the orbital process (processus orbit alls) of the palate bone 
and a portion of the body of the sphenoid bone be cut away with 
bone-forceps. 

The terminal branches of the internal maxillary artery (A. 
maxillaris interna) should now be finally reviewed. 



INTRAOSSEOUS COURSE OF N. FACIALIS, N. INTER- 
MEDIUS, AND N. ACUSTICUS. 

The N. f acialis and N. acusticus should now be followed from 
the internal acoustic meatus (meatus acusticus internus) in their 
course through the interior of the petrous portion of the tem- 
poral bone. 

Remove the temporal bone from the skull, fasten it firmly in 
a vice in its natural position, and remove the squama temporalis 
by sawing horizontally through it just above the level of the pars 
petrosa. 

Make a second horizontal cut through the pars petrosa just 
above the roof of the internal acoustic meatus ; the vestibule 
(vestibulum), cavity of the tympanum (cavum tympani), and 
mastoid cells (cellulae mastoideae) will thus be opened. Upon 
the mastoid wall (paries mastoidea) will be seen a prominent 
anteroposterior ridge (prominentia canalis f acialis), due to the 
canal in which the facial nerve runs, the facial canal of Fallopius 
(canalis f acialis [Fallopii]) (0. T. aqueduct of Fallopius). 
Notice that with this is continuous a part of the canal upon the 
labyrinthine wall of the cavum tympani, above and behind the 
stapes and the fenestra vestibuli (0. T. foramen ovale). Gain 
space by removing more of the roof of the tympanum (legmen 
tympani) with bone-forceps ; open up the facial canal on the 
labyrinthine wall (paries labyrinthica) with a chisel and expose 
corresponding part of the N. facialis. Next expose the nerve in 
the proximal portion of the facial canal by chiselling away the 
roof of the internal acoustic meatus and following the nerve 
along forward and lateralward. When the geniculate ganglion 

20 



306 



LABORATORY MANUAL. OF HUMAN ANATOMY 



of the N. intermedius is reached, it will be recognizable as a 
swelling at the point where the N. facialis bends backward to 
enter the tympanic portion of the facial canal of Fallopius. 
Avoid injury to the delicate nerve threads connected with the 
ganglion geniculi. 

Push a fine pin upward through the stylomastoid foramen 
(foramen stylomastoideum) to ascertain the course of the distal 
portion of the canalis facialis [Fallopii]. This can be opened 
by first removing the mastoid process by a coronal saw-cut in a 
plane just behind the foramen stylomastoideum. When this cut 
has gone as deep as the foramen, make a second cut at right 
angles to it, that is, a sagittal saw-cut, to meet the extremity 



FIG. 133. 



Gang, 
genie. 



N. staped 




- 



N. petros. superfic. maj. 

.N. petros. superfic. 
min. 

... N. ophth. 



%^N. max. 



N. to M. tens. tymp. 
Gang, oticum 

Chorda tympani 



-N. auric, temp. 
-N. lingualis 

--N. alveol. inf. 



Chorda tympani (after Hirschfeld). (From Poirier et Charpy, 
Traite d'Anat. hum., Paris, 1899, t. iii., 3, p. 847, Fig. 483.) 



of the first cut. Eemove the bone thus excised and open the rest 
of the facial canal with a chisel. 

Study the direction followed by the N. facialis in each of its 
four stages. Examine the following : 

Facial Nerve (N. facialis). (Vide Fig. 133.) 
Note- 

(a) Knee of the facial nerve (geniculum N. facialis) and the ganglion at 

the knee (ganglion geniculi), which really belongs to the N. inter- 
medius. 

(b) Nerve to stapedius muscle (N. stapedius). 

(c) Ramus anastomosing with the tympanic plexus (ramus anastomoticus 

cum plexu tympanico) (0. T. tympanic branch). This helps to 
form the lesser superficial petrosal nerve (N. petrosus superficialis 
minor). 



DISSECTION OF THE HEAD AND NECK 307 

Observe also (1) the communication of Arnold's nerve 
(ramus auricularis N. vagi] with the trunk of the N. facialis, a 
little above the foramen stylomastoideum ; (2) a little branch, 
inconstant, which sometimes runs to join the sympathetic plexus 
upon the A. meningea media ; it is called the external superficial 
petrosal nerve. 

Intermediate Nerve of Wrisberg (N. intermedius) (O. T. Sensory 
Part of Facial Nerve). 

To this the geniculate ganglion belongs. Study 

(a) Larger superficial petrosal nerve (N. petrosus superficialis major). 

This carries sensory fibres from the N. intermedius by way of 
the Vidian nerve to the sphenopalatine ganglion. 

(b) Cord of tympanum (chorda tympani). (Fig. 133.) 

This carries secretory fibres (sympathetic?) to the Gl. submaxil- 
laris and Gl. sublingualis and taste fibres from the tongue to the 
ganglion geniculi of the N. intermedius. Read carefully the com- 
plicated course of the chorda tympani and follow it as well as 
possible in the specimen and in models. 

Acoustic Nerve (N. acusticus) (O. T. Auditory Nerve). 

Note its position as regards the N. facialis in the meatus acus- 
ticus internus. Observe that it is formed by the fusion of two 
roots, one from the vestibule (radix vestibularis), the other 
from the cochlea (radix cochlearis). The former root carries 
sensory fibres from the vestibule and semicircular canals and 
is concerned with the maintenance of equilibrium of the head and 
eyes ; the latter root carries the impulses concerned in the sense 
of hearing and in auditory reflexes. 



LARYNX. 

Examine the position and relations of the larynx. Note that 
to its presence in the neck is due the laryngeal prominence, 
or " Adam's apple" (prominentia laryngea, pomum Adami). 
With a model of the larynx and the specimen before you, read 
a general description of its construction before beginning the 
dissection. 

Examine the relation of the larynx to the tongue. Study the 
following : 

(a) Median glosso-epiglottic fold (plica glosso-epiglottica mediana} (0. 
T. middle glosso-epiglottidean fold, or fraenum of the epiglottis). 



308 LABORATORY MANUAL OF HUMAN ANATOMY 

(b) Lateral glosso-epiglottic fold (plica glosso-epiglottica lateralis) (0. 

T. lateral glosso-epiglottidean folds). 

(c) Epiglottic vallecula (vallecula epiglottica}. 

Cavity of Larynx (Cavum laryngis). (Vide Figs. 125, 134, and 135.) 
Look into it from above, the epiglottis being pulled well for- 
ward, and observe its subdivision by the true and false vocal 
cords into three portions, the " upper subdivision," or vesti- 
bule of the larynx, the ' * middle subdivision, ' ' corresponding to 
the ventricles of the larynx, and the " inferior subdivision, " 
below the true vocal cords or folds. 



FIG. 134. 

Radix linguae 



Epiglottis 
/ Tuberculum epiglotticum 



Vallecula epiglottica v 



lateralis 
Plica 
pharyngoepiglottica - 

Aditus laryngis 

Plica ary epiglottica..- . 



Rima 
glottidis 



pars inter- 
membranacea. 



pare inter- - 
cartilaginea 



Tunica mucosa pharyngls 




Plica vocalis 

Plica ventricularis 

....Recessus piriformis 



"^Tuberculum cuneiforme 

[Wrisbergi] 

"""Tuberculum corniculatum 
[Santorini] 

Tncisura interarytaenoidea 



Cavity of the larynx viewed from above. (After Spalteholz, Hand Atlas 
of Hum. Anat., Leipzig, 1903, vol. iii. p. 559, Fig. 613.) 

The entrance to the larynx, or superior aperture (aditus 
laryngis), may now be observed. What is its shape? How is it 
bounded? The aryepiglottic fold (plica ary epiglottica) (0. T. 
arytaeno-epiglottidean fold) extends, on each side, from the lat- 
eral margin of the epiglottis in front to the tip of the arytaenoid 
cartilage behind. Note that it is formed by the junction of the 
tunica mucosa pharyngis with the tunica mucosa laryngis. In 
it near its posterior extremity are two tubercles, the cuneiform 
tubercle (tuberculum cuneiforme [Wrisbergi]) and the cornicu- 
late tubercle (tuberculum corniculatum [Santorini]), on each 



DISSECTION OF THE HEAD AND NECK 



309 



side, due to the cuneiform and the corniculate cartilage respec- 
tively; between the tubercula corniculata of the two sides, that 
is, in the median plane behind, note the interarytaenoid notch 
(incisura inter arytaenoidea). The cavity between the aditus 
and the ventricular folds (plicae ventriculares) (0. T. false vocal 
cords) is called the vestibule of the larynx (vestibulum laryngis). 
This cavity communicates, by means of the slit (rima vestibuli) 
(0. T. false glottis) between the ventricular folds (plicae ven- 
triculares) (0. T. false vocal cords), with the superior entrance 
to the glottis (aditus gtottidis superior). 



FIG. 135. 



Cavum pharyngis 
Recessus piriformis^ 

Plica ventricularis 



Ventriculus laryngis- 



Glottis'"' 




M. arytnriioiilriis trnnsvcrsus 
-M. arytaonoidcus ohliquus 



-Rima vestibuli 

Ventriculus laryngis (Morgagnii) 

- Appendix ventriculi laryngis 
Tuberculum epiglotticum 



Macula flava 
Plica vocalis > 



M. thyreoarytaenoideus (externus) 



Pars intennembranacea 

rimae glottidis 
M. vocalis 



.Pars interoartOacinea 

rimae glottidis 



Cartilago arytaenoidea 
(processus vocalis) 



Both sections of a larynx cut transversely across in the region of the ventricle. The mucous 
membrane has been removed from the right side of the lower section. (After Toldt, Anat. Atlas, Wien, 
1900, 2 Aufl., p. 445, Fig. 757.) 

On each side of the aditus glottidis superior is situated the 
ventricle of the larynx (ventriculus laryngis [Morgagnii}) (O. 
T. laryngeal sinus), with its blind sac-like appendage, appendix 
ventriculi laryngis (O. T. laryngeal pouch or sac). 

The true vocal cord, or vocal fold (plica vocalis) on each side, 
is the free margin of the three-sided prismatic projection known 
as the vocal lip (labium vocale). Note that the plica vocalis is 
situated farther medialward than the plica ventricularis. Ob- 
serve near the anterior extremity of the plica vocalis the " yel- 
low spot" (macula flava). To what is this due? 



310 LABORATORY MANUAL OF HUMAN ANATOMY 

Glottis. 

The two plicae vocales together form the glottis (O. T. glottis 
vera), the slit between them being known as the rima glottidis. 
The rima glottidis is divisible into 

(a) Intermembranous part (pars intermembranacea) (0. T. glottis vo- 

calis), the anterior longer part, between the plicae vocales. 

(b) Intercartilaginous part (pars intercartilaginea) (0. T. glottis respira- 

toria), the posterior shorter part, between the medial surfaces of 
the arytaenoid cartilages. 

The cavity below the rima glottidis i.e., the inferior cavity 
of the larynx is called the aditus glottidis inferior. It leads 
below into the trachea. 

Mucous Membrane of the Larynx (Tunica mucosa laryngis). 
Observe 

(a) Mucous laryngeal glands (Gl. laryngeae). 

(aa) Anterior (GL laryngeae anteriores), in front of and behind 

the epiglottis. 

(ab) Middle (GL laryngeae mediae), on the plicae ventriculares, 

in the ventricles, and around the cuneiform cartilages. 

(ac) Posterior (GL laryngeae posteriores) , in front of, in, and 

behind the M. arytaenoideus transversus. 

(b) Lymph-nodules of larynx (noduli lymphatici solitarii), especially 
on the posterior surface of the epiglottis and in the ventricles. 

Hyothyreoid Membrane and Laryngeal Muscles. 

With a probe stuff the ventricle of the larynx and its appen- 
dix full of moist cotton. Fasten the larynx with pins on a 
wooden block, the anterior surface upward. 

Find the ramus externus and ramus internus of the N. laryn- 
geus superior, the N. recurrens, the superior and inferior laryn- 
geal vessels, and avoid injury to them in the subsequent dissec- 
tion. Eemove the Gl. thyreoidea and the Mm. omohyoideus, 
sternohyoideus, sternothyreoideus, thyreohyoideus, and con- 
strictor pharyngis inferior. Clean and study the following 
structures : 

(a) Hyothyreoid membrane (membrana Jiyothyreoidea) (0. T. thyro- 
hyoid membrane). Observe how it is perforated by the A. 
and V. laryngea superior and by the ramus internus N. 
laryngei superioris. 

(aa) Middle hyothyreoid ligament (ligamentum Jiyofhyreoideum 

medium). 

(ab) Lateral hyothyreoid ligament (ligamentum hyothyreoideum 

laterale). 



DISSECTION OF THE HEAD AND NECK 311 

(aba) Wheat-like or triticeous cartilage (cartilago triticea). 

(b) Cricothyreoid muscle (M. cricothyreoideus}. 

(ba) Straight part (pars recta) (0. T. anterior or oblique part). 

(bb) Oblique part (pars obliqua) (0. T. posterior or horizontal 

part). 

Study its origin, insertion, action, and innervation. 

(c) Middle cricothyreoid ligament (ligamentum cricothyreoideum [me- 

dium]) (0. T. middle portion of cricothyreoid membrane). 
This is really a part of the conus elasticus (vide infra). 

Reverse position of larynx on wooden block, so that posterior 
surface looks upward. Slit open oesophagus along middle line 
behind. Dissect the tunica mucosa cautiously off the posterior 
aspect of the cricoid and arytaenoid cartilages, avoiding injury 
to the A. laryngea inferior and N. recurrens (between thyreoid 
and cricoid cartilages). 

Clean carefully the following muscles and ascertain their 
form, position, origin, insertion, action, and innervation : 

(a) Posterior cricoarytaenoid muscle (M. cricoarytaenoideus posterior). 

(b) Oblique arytaenoid muscle (M. arytaenoideus obliquus). 

(ba) Aryepiglottic muscle (M. aryepiglotticus) (0. T. aryteno- 
epiglottidean muscle). 

(c) Transverse arytaenoid muscle (M. arytaenoideus transversus) . 

From this point on, the dissection is conducted differently on 
the two sides, that on the right being made especially for the 
muscles, that on the left for the vessels and nerves. 

Fasten larynx by its left side to the wooden block. Remove 
the M. cricothyreoideus of the right side. Cut through the right 
ligamentum hyothyreoideum laterale; disarticulate the right 
inferior cornu of thyreoid cartilage from the facies articularis 
thyreoidea on the side of the cricoid cartilage. Cut vertically 
through the lamina dextra of the thyreoid cartilage a little lat- 
eral from the anterior median line and remove the detached right 
lamina. 

Clean carefully and study the form, position, origin, inser- 
tion, action, and innervation of the following muscles : 

(a) Lateral crico-arytaenoid muscle (M. cricoarytaenoideus later alls}. 

(b) Thyreo-arytaenoid muscle (M. thyreoarytaenoideus [externus]). 

(c) Thyreo-epiglottic muscle (M. thyreoepiglotticus) (0. T. thyro-epi- 

glottidean muscle). 

(d) Vocal muscle (M. vocalis) (0. T. internal thyro-arytenoid muscle). 

(This muscle is best seen in a cross-section through the whole 
larynx at the level of the true vocal cord. It lies medial from the 



312 



LABORATORY MANUAL OF HUMAN ANATOMY 



M. thyreoarytaenoideus [externus], the two being scarcely sep- 
arable. ) 
(e) Ventricular muscle (M. ventricularis) . 

This is a minute muscle in the plica ventricularis, scarcely to be 
made out except with the aid of the microscope. 

Eemove cautiously the M. cricoarytaenoideus lateralis and 
try to separate the M. thyreoarytaenoideus [externus] from the 
more medially situated M. vocalis. Ascertain the relation of the 
latter to the labium vocale and then remove it. Study the parts 
now exposed. 

FIG. 136. 

Bundle of the M. stylopharyngeus 

XSB&X 

M. aryepiglotticus 



Glandulae laryngeae mediae 
_ Tunica mucosa laryngis 

^ Mm. arytaenoidei obliqui 
_ M. arytaenoideus transversus 



M. cricothyreoideus 
Articulatio cricothyreoidea 



M. crico-arytaenoideus posterior 



M. ceratocricoideus (Var.) 

Muscles of larynx seen from behind. Part of the right lamina of the thyreoid cartilage has been 
removed. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 444, Fig. 751.) 

Elastic Membrane of Larynx (Membrana elastica laryngis). 

(a) Elastic cone (conus elasticus} (0. T. cricothyroid membrane). 

(aa) Vocal ligament (ligamentum vocale} (0. T. inferior thyro- 
arytenoid ligament). 

Observe that this is really the upper free 
thickened border of the conus elasticus. Note 
especially its anterior and posterior attachments. 
Between the two ligamenta vocalia in front 
observe 
( aaa ) Sesamoid cartilage (cartilago sesamoidea}. 

(b) Quadrangular membrane (membrana quadrangularis) . 

(ba) Ventricular ligament (ligamentum ventriculare) (0. T. 
superior thyro-arytenoid ligament). 




DISSECTION OF THE HEAD AND NECK 313 

Observe that this ligament is simply the thickened 
lower margin of the quadrangular membrane. 

Next dissect away on the right side the remains of the plica 
aryepiglottica, membrana quadrangularis, plica ventricularis, 
plica vocalis, and comis elasticus, but leave the arytaenoid and 
corniculate cartilages undisturbed. Remove the cuneiform car- 
tilage from the right aryepiglottic fold and preserve it for subse- 
quent study. The left wall of the cavity of the larynx may now 
be thoroughly studied, and any points not well made out in the 
preliminary study of the cavity before it was opened should be 
cleared up before going further. 

Vessels and Nerves of Larynx. 

The dissection of the vessels and nerves of the interior of the 
larynx should now be undertaken. 

(a) Internal ramus of superior laryngeal nerve (ramus internus 'N. laryn- 

gei superioris). 

(aa) Ramus anastomosing with inferior laryngeal nerve (ramus 
anastomoticus cum N. laryngeo inferiore) (0. T. Galen's 
loop). 

Make traction on this nerve outside the larynx where 
it pierces the membrana hyothyreoidea and cut through the 
tunica mucosa laryngis on the inner surface of this mem- 
brane and find the nerve and artery. Gradually dissect off 
the tunica mucosa and expose their branches. What is the 
function of the internal ramus of the N. laryngeus superior ? 

(b) Inferior laryngeal nerve from the recurrent nerve (N. laryngeus in- 

ferior N. recurrentis) (0. T. recurrent laryngeal nerve). 

To see it well, draw the thyreoid cartilage well lateral- 
ward. 

(ba) Anterior ramus (ramus anterior). 

What muscles are innervated by it ? 

(bb) Posterior ramus (ramus posterior). 

What muscles does it supply? 

(c) Superior laryngeal artery (A. laryngea superior). 

(d) Inferior laryngeal artery (A. laryngea inferior). 

Cartilages and Ligaments of Larynx. 

Some of these have already been examined. 

Remove the rest of the mucous membrane and the muscles 
from the cartilages, taking care not to injure the ligaments or 
the smaller cartilages. Study 

Epiglottis and its Ligaments, 
(a) Epiglottis. 

Stem of epiglottis (petiolus epiglottidis) . 



314 LABORATORY MANUAL OF HUMAN ANATOMY 

(ab) Epiglottic tubercle (tuberculum epiglotticum) (0. T. 

cushion of epiglottis). 

(ac) Epiglottic cartilage (cartilago epiglottica) . 

'(&) Thyreo-epiglottic ligament (ligamentum thyreoepiglotticum) (0. 

T. thyro-epiglottidean ligament), 
(c) Hyo-epiglottic ligament (ligamentum hyoepiglotticum) (0. T. hyo- 

epiglottidean ligament). 
Thyreoid Cartilage (Cartilago thyreoidea}. 

(a) Right and left plates (laminae [dextra et sinistra]) (0. T. ala). 

(b) Superior thyreoid notch (incisura thyreoidea superior). 

(c) Inferior thyreoid notch (incisura thyreoidea inferior). 

(d) Superior thyreoid tubercle (tuberculum thyreoideum superius). 

(e) Inferior thyreoid tubercle (tuberculum thyreoideum inferius). 

(f) Oblique line (linea obliqua). 

(g) Superior horn (cornu superius). 
(h) Inferior horn (cornu inferius). 

(i) Thyreoid foramen (foramen thyreoideum). 

Cricothyreoid Joint (Articulatio cricothyreoidea) . 

(a) Capsule of joint (capsula articularis cricothyreoidea). 

(b) Lateral ceratocricoid ligaments (Ligg. ceratocricoidea lateralia}. 

(c) Anterior ceratocricoid ligament (Lig. ceratocricoideum anterius). 

(d) Posterior ceratocricoid ligaments (Ligg. ceratocricoidea posteriora). 
Divide the structures connecting the thyreoid cartilage to the cricoid 

and remove the former. 

Cricoid Cartilage (Cartilago cricoidea). 

(a) Arch (arcus [cartilaginis cricoideae]) . 

(b) Lamina (lamina [cartilaginis cricoideae]). 

(c) Arytaenoid articular surface (fades articularis arytaenoidea) . 

(d) Thyreoid articular surface (fades articularis thyreoidea). 

Observe also the cricotracheal ligament (ligamentum crico- 
tracheale). 

Corniculate Cartilage (Cartilago corniculata [Santorini]) (0. T. carti- 
lage of Santorini). 

(a) Arycorniculate joint (synchondrosis arycorniculata) . 

(b) Corniculopharyngeal ligament (Lig. corniculopharyngeum) (0. T. 

Lig. jugale). 
(ba) Cricopharyngeal ligament (Lig. cricopharyngeum) . 

Arytaenoid Cartilage (Cartilago arytaenoidea). 

Remove one in order to study the cartilage itself; leave the 
other in situ for the study of the ligaments. 

(a) Tip or apex (apex [cartilaginis arytaenoideae]). 

(b) Base (basis [cartilaginis arytaenoideae]). 

(ba) Articular surface (fades articularis). 

(c) Posterior surface (fades posterior). 

(d) Medial surface (fades medialis) (0. T. internal surface). 

(e) Lateral surface (fades lateralis) (0. T. antero-external surface). 

(ea) Nodule or hillock (colliculus) . 

(eb) Arched ridge (crista arcuata). 

(ec) Triangular depression (fovea triangularis) . 

(ed) Oblong depression (fovea oblonga). 



DISSECTION OF THE HEAD AND NECK 



315 



(/) Vocal process (processus vocalis). 

(g) Muscular process (processus muscularis). 

Cuneiform Cartilage (Cartilago cuneiformis [Wrisbergi] ). 

Was this present on each side in the subject under dissection? 

Crico-arytaenoid Joint (Articulatio cricoarytaenoidea). 

(a) Joint-capsule (capsula articularis cricoarytaenoidea). 

(b) Posterior crico-arytaenoid ligament (Lig. cricoarytaenoideum pos- 

terius). 

The student is advised to read at this juncture on the physi- 
ology of voice-production and to study the action of the various 
laryngeal muscles. Why does food not enter the larynx during 
deglutition? 

TONGUE (LINGUA). 

Examine the following : 



(a) Back of tongue (dorsum linguae). 

(b) Root of tongue (radix linguae). 

To what is it attached? 



(Vide Figs. 125, 137.) 



FIG. 137. 



Epiglottis^ 

Plica glossoepiglottica mediana 
Vallecula epiglottica 

Plica glossoepiglottica ~ 
lateralis 

Foramen caecum linguae 
(Morgagnii) 
Sulcus terminalis^ 
linguae 



Papillae lenticulares-----'- 
Papillae vallatae-* 1 "^" 
Papillae foliatae-=.- 

Papillae conicae- ' 
Papillae fungiformes 



Papillae filiformes^- 



Radix linguae 

Tonsilla lingualis 




Folliculi linguales 



Tonsilla palatina (in 

horizontal cross-section) 

-Sinus tonsillaris 



Plica triangularis 
Arcus glossopalatinus 

Corpus linguae (dorsum) 



-Margo lateralis linguae 
._Sulcus medianus linguae 



-Apex linguae 

Dorsal surface of tongue. (After Toldt; Anat. Atlas, Wien, 1900, 2 Aufl., p. 403, Fig. 649.) 

(c) Body of tongue (corpus linguae). 

(d) Inferior surface (fades inferior [linguae]). 

(da) Fimbriated fold (plica fimbriata). 



316 LABORATORY MANUAL OF HUMAN ANATOMY 

(e) Tip of tongue (apex linguae). 

(f) Mucous membrane of tongue (tunica mucosa linguae). 

This has already been studied in connection with the 
mouth cavity, but should now be reviewed. 

(fa) Frenuluni ("bridle" or "check-rein") of tongue (frenulum 

linguae). 

(fb) Lingual papillae (papillae linguales). 

(fba) Filiform papillae (papillae filiformes). 

(fbb) Conical papillae (papillae conicae). 

(fbc) Fungiform papillae (papillae fungiformes). 

(fbd) Lenticular papillae (papillae lenticular -e s) . 

(fbe) Vallate papillae (papillae vallatae) (0. T. cireum- 

vallate). 

(fbf) Foliate papillae (papillae foliatae). 

(g) Median sulcus of tongue (sulcus medianus linguae), 
(h) Terminal sulcus (sulcus terminalis) . 

FIG. 138. 

M. verticalis linguae 
M. transversus linguae 



Fascia linguae 




-*-M. longitudinalis 
superior 



Glandula lingualis 

anterior (Blandini, 

Nuhni) 

Plica fimbriata 

Facies inferior linguae Septum linguae 

Transverse section through the tongue near the tip. (After Toldt, Anat. Atlas, Wien, 1900, 

2 AufL, p. 405, Fig. 652. 

(t) Blind foramen of tongue (foramen caecum linguae [Morgagnii]). 
(ia) Lingual duct (ductus lingualis). 

(iaa) Thyreoglossal duct (ductus thyreoglossus). 
(j) Lingual tonsil (tonsilla lingualis). 

(ja) Lingual folliculi (folliculi linguales). 
(k) Muscles of tongue. 

Remove the tunica mucosa linguae from the right side of the 
tongue; isolate the individual muscles and review their form, posi- 
tion, origin, insertion, action, and innervation. 
Extrinsic muscles (vide Fig. 112) : 

(ka) Genioglossus muscle (M. genioglossus). 
(kb) Hyoglossus muscle (M. hyoglossus). 
(kc) Chondroglossus muscle (M. chondroglossus). 
(kd) Styloglossus muscle (M. styloglossus) . 
Intrinsic muscles (vide Fig. 138) : 

(ke) Superior longitudinal muscle of tongue (M. longitudinalis 

superior linguae) (0. T. superficial lingual). 

(kf) Inferior longitudinal muscle of tongue (M. longitudinalis in- 
ferior linguae) (0. T. inferior lingual). 



DISSECTION OF THE HEAD AND NECK 317 

(kg) Transverse muscle of tongue (M. transversus linguae), 
(kh) Vertical muscle of tongue (M. verticalis linguae). 
(I) Septum of tongue (septum linguae), 
(m) Nerves of tongue (to be studied on left side of tongue). 
(ma) Glossopharyngeal nerve (N. glossopharyngeus). 

(maa) Lingual rami (rami linguales). 
(mb) Lingual nerve (N. lingualis). 

(mba) Sublingual nerve (N. sublingualis) . 
(mbb) Lingual rami (rami linguales). 

Read on the relations of the N. trigeminus and 
the N. intermedius, respectively, to the N. lingualis. 
(me) Hypoglossal nerve (N. hypoglossus) . 

(mca) Lingual rami (rami linguales). 

What do they innervate? 
(n) Lingual artery (A. lingualis). 

(na) Dorsal rami of tongue (rami dor sales linguae), 
(nb) Deep artery of tongue (A. profunda linguae) (0. T. ranine 
artery). 

BRAIN (ENCEPHALON). 

The student should now undertake the systematic study of 
the brain. 

Membranes of Brain (Meninges encephali). 

(a) Dura mater of the brain (dura mater encephali). This has been 

examined before (p. 198). 

(b) Arachnoid of brain (arachnoidea encephali). 

(ba) Subarachnoid cavity (cavum subarachnoideale) . 

(bb) Subarachnoid cisterns (cisternae subarachnoideales) . 
Divide the arachnoid in the middle line over the anterior surface of 

the medulla oblongata and pons, and turn the two halves lateralward. 

(bba) Cerebellomedullary cistern (cisterna cerebellomedul- 

laris) (0. T. cisterna magna). 

(bbb) Cistern of the lateral fossa of the cerebrum (cis- 

terna fossae lateralis cerebri [Sylvii]). Note 
relation to A. cerebri media. . 

(bbc) Cistern of the chiasm (cisterna chiasmatis). 

(bbd) Interpeduncular cistern (cisterna interpeduncularis) 

(0. T. cisterna basalis). 

(bbe) Cistern of the large veins of the cerebrum (cisterna 

venae magnae cerebri). 

(be) Arachnoideal granulations (granulationes arachnoideales 
[Pacchioni]) (0. T. Pacchionian bodies).. (Vide Fig. 84.) 

(c) Pia mater of brain (pia mater encephali). Study this in its relation 

to the surface of the brain. The portions of the pia in the interior 
of the brain will be studied later on. 



318 



LABORATORY MANUAL OF HUMAN ANATOMY 
FIG. 139. 



in 




-vm 



ncl 



Cerebrum, with a portion of the spinal cord, viewed from the ventral surface. On the right-hand side 

the ventral roots are cut off short and turned medialward. 

I, tractus olfactorius ; II, tractus opticus ; III, N. oculomotorius ; IV, N. trochlearis ; V, N. trige- 
minus, portio major et portio minor; VI, N. abducens; VII, N. facialis ; Vir, N. intermedius; VIII, 
N. acusticus ; IX, N. glossopharyngeus ; X, N. vagus ; XI, N. accessorius ; XII, N. hypoglossus ; nc I, 
N. cervicalis primus. (After Rudinger and Henle, from A. Rauber's text-book.) 

Blood-vessels of Brain. (Vide Fig. 140.) 

Remove the arachnoidea encephali from the base of the cere- 
brum and from the anterior surface of the rhombencephalon. 
With scissors and forceps follow the blood-vessels, beginning at 



DISSECTION OF THE HEAD AND NECK 



319 



the large trunks and passing out to the finer subdivisions. Do 
not injure the brain substance. 



FIG. 140. 




The arteries of the base of the brain. 

T, lobus temporalis (cut off) ; T-XII, Nn. cerebral es; Accra, art. cerebri anterior; Coma, art. com- 
municans anterior ; A FSy, art. cerebri media ; A lent, art. lenticularis ; 1-5, the cortical chief branches 
of the A cer. med. ; cp, art. communicans posterior ; A cha, art. chorioidea ; ch, a small branch of the 
preceding which goes into the plexus chorioidei ; x, lateral branches of the A. com. post. ; A cp, art. 
cerebri posterior ; p, short branches of the preceding ; A bas, art. basilaris ; A t, art. temporalis (Duret) ; 
Aocc, art. occipitalis (Duret) ; JUvrv//>. art. cerebelli superior; A cer med, art. cerebelli inferior ante- 
rior; A cerinf, art. cerebelli inferior posterior : .1 n rf, art. vertebralis; Spa, art. spinalis anterior. (After 
Monakow, Gehirnpathologie, Wien, 1897, p. 668, Fig. 151.) 



Arteries. 

(a) Vertebral artery (A. vertebralis). 

(aa) Posterior spinal artery ( A. spinalis posterior). 

(ab) Anterior spinal artery (A. spinalis anterior). 



320 LABORATORY MANUAL OF HUMAN ANATOMY 

(ac) Meningeal ramus (ramus meningeus) (0. T. posterior nien- 

ingeal branch). 

(ad) Posterior inferior cerebellar artery (A. cerebelli inferior 

posterior), 
(b) Basilar artery (A. basilaris). 

(ba) Anterior inferior cerebellar artery (A. cerebelli inferior 

anterior). 

(bb) Internal auditory artery (A. auditiva interna) (0. T. 

auditory artery). 
(be) Rami to pons (rami ad pontem) (0. T. transverse arteries). 

(bd) Superior cerebellar artery (A. cerebelli superior). 

(be) Posterior cerebral artery (A. cerebri posterior). 

(bf) Arterial circle of Willis (circulus arteriosus [Wittisi]). 




Lateral view of the right hemisphere with the distribution of the A. cerebri media. 
Art. FS, art. cer. med. ; I, II, III, IV, V, the five chief branches of the preceding ; Ilia, lateral 
twigs of the third branch of the A. cer. med. ; Fc, sulcus centralis ; FS, fissura cerebri lateralis [Sylvii] ; 
JP, sulcus interparietalis ; t, sulcus temporalis superior ; F^-Fy, superior, middle and inferior frontal 
gyri ; SM, gyrus supramarginalis ; Ang, gyrus angularis ; Oi-0 3 , gyri occipitales laterales. The dotted 
line indicates the extent of the distribution of the A. cer. med. (After v. Monakow, Gehirnpath., Wien, 
1897, p. 673, Fig. 154.) 

(c) Internal carotid artery (A. carotis interna). 

(ca) Posterior communicating artery (A. communicans poste- 

rior). 

(cb) Chorioid artery (A. chorioidea) (0. T. anterior choroidal). 

(cc) Anterior cerebral artery (A. cerebri anterior). 

(cca) Anterior communicating artery (A. communicans 
anterior). 



DISSECTION OF THE HEAD AND NECK 



321 



(cd) Middle cerebral artery (A. cerebri media) (0. T. arteria 
fossae Sylvii). (Vide Figs. 140-142.) 

Distinguish between basal and central branches and cortical 
branches of the cerebral arteries. Why should emboli pass more 



Pare 



Gcp 



fo> 




Ch 



Frontal section through the right cerebral hemisphere (plane of the gyms centralis and chiasma 
opticum). Origin and course of the A. lenticularis as well as of the cortical branches of the A. cer- 
ebri media, schematically shown. 

Gca, anterior, Gcp, posterior central gyrus; Pare, lobulus paracentralis ; T]-T 4 , first to fourth tem- 
poral gyrus; S, corpus callosum; Am, nucleus amygdalae ; J, island; 7-X tissura rcrrbri latrralis 
[Sylvii] ; Li, nucleus lenticularis ; Thai, thalamus ; CH, gyrus hippocampi ; /, field of the A. cer. ant. ; 
//, of the A. cer. med. ; III, of the A. cer. post. The dotted lines show the boundaries between these. 
Ch, chiasma opticum ; Car, A. cer. inf. ; 1, stem of the A. cer. med. ; ta, course to the island is shown l>y 
dotted outline ; 2, lenticulo-striate arteries ; 5, lenticulo-optic arteries ; , cortical branches of the A. cer. 
med. ; a, medullary branches of the cortical twigs of the A. cer. med. (After v. Monakow, Gehirn- 
path., Wien, 1897, p. 674, Fig. 155.) 

frequently into the middle cerebral than into the anterior cere- 
bral artery! The " artery of cerebral hemorrhage " (Charcot), 

21 



322 LABORATORY MANUAL OF HUMAN ANATOMY 

so called on account of the frequency of its involvement, as com- 
pared with the other cerebral arteries, is one of the lenticular 
branches of the A. cerebri media. For a full description of the 
cerebral arteries and their relation to cerebral hemorrhages, see 
v. Monakow, Gehirnpathologie, pp. 667-792. 

Veins (Venae cerebri). 
Superficial. 

(a) Superior cerebral veins (Vv. cerebri superiores). 

(b) Middle cerebral vein (V. cerebri media}. 

(c) Inferior cerebral veins (Vv. cerebri inferiores). 

(d) Superior cerebellar veins (Vv. cerebelli superiores). 

(e) Inferior cerebellar veins (Vv. cerebelli inferiores). 

(f) Basal vein (V. basalis [Bosenthali]) . 
Deep. These may be studied later. 

Removal of Meninges and Superficial Blood-vessels. 

Place the brain on the table, with the base upward. With 
forceps and scissors, cautiously remove the membranes and 
blood-vessels from the surface. The pia over the medulla oblon- 
gata and lower part of pons may be left until after the cerebral 
nerves have been identified and studied. The base of the brain 
is now exposed, including a part of the basis cerebri and the 
inferior (anterior) surfaces of the pons, medulla oblongata, and 
cerebellum. Observe 

(a) Longitudinal fissure of cerebrum (fissura longitudinalis cerebri}. 

(b) Lateral fissure of cerebrum (fissura cerebri lateralis [Sylvii]) (0. T. 

fissure of Sylvius). 

(c) Temporal pole (polus temporalis). 

(d) Optic chiasm (chiasma opticum) with optic nerves (Nn. optici) and 

optic tracts (tractus optici). 

(e) Hypophysis (hypophysis) (0. T. pituitary body). This may have 

been left in the sella turcica. 

(f) Infundibulum (infundibulum) ("funnel"). 

(g) Ash-like tuber (tuber cinereum). 

(h) Mammillary bodies (corpora mammillaria) . 

(i) Cerebral peduncles (pedunculi cerebri) (0. T. crura cerebri). 

(j) Interpeduncular fossa (fossa inter peduncularis [Tarini]). 

(ja) Anterior recess (recessus anterior). 

(jb) Posterior recess (recessus posterior). 

(fr) Posterior perforated substance (substantia perforata posterior). 
(I) Pons (pons [Varolii]) ("bridge"). 
(m) Medulla oblongata. 

Cerebral Nerves (Nn. cerebrales). (Figs. 139 and 143.) 

The " superficial origins" of the cerebral nerves i.e., their 
regions of exit from or entrance into the brain may now be 
examined. 



DISSECTION OF THE HEAD AND NECK 



323 



I. Olfactory nerves (Nn. olfactorii). Do not confuse these with the 
olfactory tracts. Try to find the fine threads of the Nn. olfactorii 
penetrating- the ventral surface of each bulbus olfactorius. They 
come from the nasal mucous membrane, through the lamina 
cribrosa of the ethmoid bone. 

II. Optic nerve (N. opticus). It runs from the back of the eyeball to the 
optic chiasm. The student's later studies will show him that the 
optic nerve is really not a peripheral nerve, like the other cerebral 
nerves, but rather a part of the central nervous system. 



Gyrus rectus 

\ 



FIG. 143. 



Fissura longitudinalis cerebri 



Trigonum olfactorium 
N. opticus^ 

Chiasma opticum 
Corpus mammillare 

Uncus (gyri hippocampi) v 

N. oculomotorius 
Pedunculus cerebri 

Substantia perforata posterior 
(Fossa interpeduncularis) T\ 

(Pons Varolii) 




N. trigeminus ~i_ 

N. abducens 
N. facialis .. 

N. intermedius 



N. acustieus 
N. hypoglossus 

Pyramis (medullae oblongatae) 
Radix anterior N. cervicalis I. " 

Fissura mediana anterior 
Decussatio pyramidum 



Tractus olfactorius 

Stria olfactoria medialis 

Stria olfactoria intermedia 

Stria olfactoria lateralis 

' Substantia perforata 
anterior 

^ Tuber cinereum and 

infundibulum 
Tractus opticus 

- - Sulcus n. oculomotorii 

^ Radix lateralis > tractus 
~~- Radix medialis) optici 

v Corpus geniculatum laterale 
Fasciculus obliquus (pontis) 
-^. Sulcus basilaris 

- Brachium pontis 

Foramen caecum 
" Oliva 

Corpus restiforme 
Fibrae arcuatae externae 

Sulcus lateralis anterior 
Funiculus lateralis 



The medulla oblongata, pons (Varolii), cerebral peduncles, and part of the floor of the midbrain. 
Seen from the basal surface. (After Toklt, Anal. Atlas, Wien, 1903, 3 Aufl., p. 765, Fig. 1174.) 



III. Oculomotor nerve (N. oculomotorius). Look for it in the fossa inter- 

pedunculnris. It belongs to the midbrain. 

IV. Trnclilear nerve (X. t rochlearis) . While all the other cerebral nerves 

emerge from the ventral aspect of the brain-stem, this nerve 
emerges on the dorsal aspect. Its exact origin will be seen later. 
Note that it is on the lateral aspect of the pedunculus cerebri, while 
the oculomotor nerve is on the medial aspect of that structure. 
V. Trigeminal nerve (X T . Irigeminus). 

(a) Larger portion (portio major], sensory. 

(b) Smaller portion (portio minor}, motor. 



324 LABORATORY MANUAL OF HUMAN ANATOMY 

VI. Abducent nerve (N. abducens). Emerges on each side at the junction 

of the pons with the medulla oblongata. 
VII. Facial nerve (N. facialis). 

(a) Intermediate nerve (N. intermedius) (0. T. pars intermedia, 

or nerve of Wrisberg). 
VIII. Acoustic nerve (N. acusticus) (0. T. auditory nerve). 

(a) Vestibular root (radix vestibularis) . This runs medial to 

the restiform body. 

(b) Cochlear root (radix cochlearis). This runs lateral from 

the restiform body. 

IX. Glossopharyngeal nerve (N. glossopharyngeus) . It may be difficult 
to decide exactly how many fila radicularia belong to this nerve and 
how many to X. and XI. 

X. Vagus nerve (N. vagus) (0. T. pneumogastric nerve). 
XL Accessory nerve (N. accessorius) (0. T. spinal accessory). 
XII. Hypoglossal nerve (N. hypoglossus) . Emerges between the oliva and 
the pyramis, by several fasciculi (fila radicularia). 

Larger Subdivisions of the Brain. 

Note the subdivision into rhomboid brain (rhombencephalon) 
and cerebrum, the junction being that between pons and mid- 
brain. 

The rhombencephalon includes 

(a) After-brain (myelencephalon) (" medullary brain"). 

(b) Hind-brain (metencephalon), subdivisible into 

( ba ) Cerebellum. 

(bb) Pons [Varolii]. 

The cerebrum includes 

(a) Midbrain (mesencephalon) . 

(b) Forebrain (prosencephalon), consisting of 

(ba) Interbrain (diencephalon) and 

(bb) End-brain (telencephalon) . 

Examine carefully the longitudinal fissure of the cerebrum 
(fissura longitudinalis cerebri) (0. T. great longitudinal fissure). 

The following table shows the derivatives of the three cere- 
bral vesicles. 



DISSECTION OF THE HEAD AND NECK 



325 






H 







- 



ombencep 

Lozenge-sha 



Rh 






a 

a 

I 

R 

g 



Metencephalon 



T 

31 

& j 

o a 
f3 t^- 




I 



E 



( Hvpo- 
rs nptica 



g .y 
I 1 



C 



-^ = 

= 

1 

- 



r 



5 ~ 

q 



JOTJOJSOJ -9J90 ajppijn 



v ja;) JQIJ 



326 LABORATORY MANUAL OF HUMAN ANATOMY 

The student may now remove one cerebral hemisphere (hemi- 
sphaerium cerebri). With a very sharp, thin knife, cut through 
the right cerebral peduncle just behind the right corpus mam- 
millare. Turn the brain over ; press the two hemispheres apart 
by widening the longitudinal fissure of the cerebrum; expose 
the corpus callosum and cut through it and the tissues beneath, 
as near the middle line as possible, or a very little to the left of 
it, so as to leave the septum pellucidum on the right hemisphere. 
Carry the incision backward to meet the transverse incision 
already made through the cerebral peduncle. This right hemi- 
sphere may be kept in the preserving fluid while the rest of the 
brain is being studied. 

External Morphology of Rhomboid Brain and Midbrain 
(Rhombencephalon and Mesencephalon). 

Lift the cerebellum gently from behind and observe the rela- 
tion of its inferior surface to the medulla oblongata and ven- 
triculus quartus. With a sharp, thin brain-knife, cut through 
the cerebellum in the middle line of the worm (vermis). Do no 
injury to the floor of the fourth ventricle, but permit the incision 
to pass forward through the anterior medullary velum as far 
as the inferior colliculi of the midbrain. Cut through the three 
cerebellar peduncles on the right side, the superior peduncle 
(brachium conjunctivum) , the middle peduncle (brachium pon- 
tis), and the inferior peduncle (corpus restiforme). Eemove 
the right half of the cerebellum and preserve it for further study. 

Make three drawings showing anterior, lateral, and poste- 
rior views of rhombencephalon, and illustrating the following 
structures : 

Medulla Oblongata. 

(a) Anterior median fissure (fissura mediana anterior}. 

(b) Posterior median fissure (fissura mediana posterior). 

(c) Blind foramen (foramen caecum). 

(d) Pyramid (pyramis [medullae oblongatae] ). 

(e) Decussation of pyramids (decussatio pyramidum). 

(f) Anterior lateral sulcus (sulcus lateralis anterior}. 

(g) Posterior lateral sulcus (sulcus lateralis posterior), 
(h) Olive (oliva) (0. T. olivary eminence). 

(i) Restiform body (corpus restiforme) (0. T. inferior cerebellar 

peduncle). 

(j) Lateral funiculus (funiculus lateralis). 
(k) Cuneate funiculus (funiculus cuneatus) (0. T. column of Bur- 

dach). 



DISSECTION OF THE HEAD AND NECK 



327 



(I) Gray or ashen tubercle (tuberculum cinereum) (0. T. tubercle of 
Rolando). 

(m) Slender funiculus (funiculus gracilis) (O. T. column of Goll). 
(ma) Club (clava). 

(n) External arcuate fibres (fibrae arcuatae externae) (O. T. super- 
ficial arcuate fibres). 

Pons [Varolii]. 

(a) Basilar groove (sulcus basilaris), 

(b) Oblique bundle of pons (fasciculus obliquus [pontis]). 

(c) Brachium ("arm") of pons (brachium pontis) (0. T. middle cere- 

bellar peduncle). 



Sulcus hypothalamicus [Monroi] 
Corpus fornicis \ 
Foramen interventriculare [Monroi] \ 
Septum pellucidum , ' 
Lamina rostralis 
Rostrum corporis 

callosi 
Genu corporis 

callosi 

Gyrus subcallo-l 
sus [Pedunculuss 
corporis callosi] . 
Sulcus parolfac- 
torius posterior 
Commissura ante- 
rior [cerebri] - -JHi 
Sulcus parollac- 

tori us anterior ^-- 

Area parolfac- ...s 

toria [Brocae] 
Lamina terminalis --_ ' f 
Recessus optic us -*^ 
Recessus inf undibuli _-* 
Chiasma opticum 

Infundibulum 
Hypo- \ lobus anterior 
physis | lobus posterior 

Recessus anterior fossae-' / / 
interpeduncularis / ,. ' / 
Corpus mammillare'' // 
Fossa interpeduncularis [Tarini] / 

Nervus oculomotorius-' / / 

Sulcus n. oculomotorii / 

Recessus posterior fossae interpeduncularis / , 
Decussatio brachii conjunrtivi 
Pons [Varolii] (fibrae superficiales) 
Fasciculi longitudinal es [pyramidal es] 

Foramen caecum / 
Fasciculus longitudinalis medialis 
Medulla spinalis- 



FIG. 144. 

Truncus corporis callosi 
; Massa intermedia 
Thalamus 

j Tela chorioidea ventriculi tertii 
Ventriculus tertius 
I Aditus ad aquaeductum cerebri 
Commissura posterior [cerebri] 
' Recessus pinealis 

Commissura habenularum 
Recessus suprapinealis 



Corpus pineale 
^ Lamina quadrigemina 
!k/ Aquaeductus cerebri [Sylvii] 
Splenium corporis callosi 

Nucleus n. trochlearis 
^ ,Velum medullare anterius 
mf Lobulus centralis 

Mi.nticulus (Culmen) 
^^^^.Lingula cerebelli 
^L Ventriculus quartus 




Fastigium 

. Monticulus (Declive) 

k . Laminae medullares 



Folium 

vermis 



XTuber yennia 
" x ^ Pyramis 
[vermis] 



t -^ 'Corpus medullare 

Nodulus \ Uvula [vermis] 

Velum medullare posterius 



Median section of the brain-stem. Right half seen from the left. (Only a small part of the pallium is 
shown.) (After Spalteholz, Hand Atlas of Hum. Anat., Leipzig, 1903, p. 63G, Fig. 695.) 



Isthmus of Rhombencephalon (Isthmus rhombencephali). 

(a) Brachium conjunctivum ("connecting arm") of cerebellum (bra- 

chium conjunctivum [cerebelli]) (0. T. superior cerebellar pe- 
duncle). 

(b) Fillet or ribbon (lemniscus) . 

(ba) Lateral fillet (lemniscus lateralis). 

(bb) Medial fillet (lemniscus medialis) (0. T. ribbon of Reil). 
(be) Trigone of fillet (trigonum lemnisci). 



328 



LABORATORY MANUAL OF HUMAN ANATOMY 



(c) Anterior medullary velum (velum medullare anterius) (0. T. valve 

of Vieussens). 

(ca) Frenulum ("rein" or "check-rein") of anterior medullary 
velum (frenulum veli medullaris anterioris). 

Midbrain (Mesencephalon). 

(a) Peduncle of cerebrum (pedunculus cerebri) (0. T. crus cerebri). 

(aa) Aqueduct of cerebrum (aquaeductus cerebri [Sylvii]) (0. 

T. iter e tertio ad quartum ventriculum). 

(ab) Lateral sulcus (sulcus lateralis). 

(ac) Sulcus of oculomotor nerve (sulcus N. oculomotorii) . 

(&) Quadrigeminal bodies (corpora quadrigemina) (0. T. optic lobes). 

(ba) Quadrigeminal layer (lamina quadrigemina). 

(bb) Superior hillock (colliculus superior) (0. T. anterior 

body or nates). 

(be) Inferior hillock (colliculus inferior) (0. T. posterior body 
or testis). 

(bd) Superior quadrigeminal brachium (brachium quadrigemi- 

num superius). 

(be) Inferior quadrigeminal brachium (brachium quadrigemi- 

num inferius). 



FIG. 145. 



Incisura cerebelli anterior 
Lobulus centralis 



Monticulus 




.Ala lobuli centralis 

Pars anterior \ lobuli quad- 
Pars posterior/ rangularis 



., Sulci cerebelli 



Folium vermis- 

Incisura cerebelli 
posterior 



Lobulus semilu- 
naris superior 
Sulcus horizontalis 

cerebelli 
Lobulus semilunaris inferior 



The upper surface of the cerebellum. (After Toldt, Anat. Atlas, Wien. 1903, 3 AufL, p. 770, 

Fig. 1182.) 

Cerebellum. 

(a) Convolutions of cerebellum (gyri cerebelli). 

(b) Sulci of cerebellum (sulci cerebelli). 

(c) Cerebellar vallecula ("little valley") (vallecula cerebelli). 

(d) Anterior notch of cerebellum (incisura cerebelli anterior) (0. T. 

semilunar notch). 

(e) Posterior notch of cerebellum (incisura cerebelli posterior) (0. 

T. marsupial notch). 

(f) Horizontal sulcus of cerebellum (sulcus horizontalis cerebelli) (0. 

. T. great horizontal fissure). 

(g) Transverse fissure of cerebellum (fissura transversa cerebelli). 
(h) Vermis ("worm") (vermis). 

(ha) Lingua ("tongue") of cerebellum (lingua cerebelli). 



DISSECTION OF THE HEAD AND NECK 



329 



(haa) Vinculum of the lingua ("tongue-band") (vin- 

culum linguae cerebelli). 

(hb) Central lobule (lobulus centralis) (0. T. lobus centralis). 
(he) Monticulus (monticulus) (" little mountain"). 

(hca) Culmen (culmen) ("summit"). 

(hcb) Declive (declive) ("slope or descent"). 



FIG. 146. 



Incisura 
cerebelli anterior.^ 



Flocculus 



Uvula vermis, 




Tuber vermis 
Folium vermis - 



Lobulus 
biventer 



Lobulus 
semilunaris 

inferior 
Sulcus 
horizontals 
cerebelli 
Lobulus semi- 
lunaris 
superior 



Incisura cerebelli posterior" 

The lower surface of the cerebellum. (After Toldt, Anat. Atlas, Wien, 1903, 3 Aufl., p. 770, Fig. 1183.) 



(hd) Folium vermis (folium vermis) ("leaflet of worm") (0. T. 

folium cacuminis). 

(he) Tuber of vermis (tuber vermis) (0. T. tuber valvulus). 
(Tif) Pyramid of vermis (pyramis [vermis]). 



FIG. 147. 



Vellum medullare anterius 
Ala lobuli centralis. 

Vineulumlingulae cerebelli. 
Hemisphaerium cerebelli 
(facies superior) 

Flocculi seeuiKlarii 



Vermis superior 

"obulus centralis 

Lingula cerebelli 

Brachium conjunctivmn 
Corpus restiforme 
Brachium pontis 

Sulcus horizon- 
.talis cerebelli 




Flocculus 



Hemisphaeriurn cerebelli 

iiacics inferior) 



Vermis inferior 



Fissura transversa 

cerebelli 
^ Velum medullare posterius 

"Nodulus vermis 
Uvula vermis 



Vallecula cerebelli ' 
The anterior surface of the cerebellum. (After Toldt, Anat. Atlas, Wien, 1903, 3 Aufl., p. 771, Fig. 1184.) 



(hg) Uvula of vermis (uvula [vermis]). 
(hh) Nodule (nodulus). 

(i) Hemisphere of cerebellum (hemisphaerium cerebelli). 
(ia) Superior surface (facies superior). 



330 



LABORATORY MANUAL OF HUMAN ANATOMY 



(iaa) Wing of central lobule (ala lobuli centralis). 
- (iab) Quadrangular lobule (lobulus quadrangularis) (0. 
T. quadrate lobule). 

(1) Anterior part (pars anterior), 

(2) Posterior part (pars posterior), 

(0. T. two anterior erescentic lobules). 

(iac) Superior semilmiar lobule (lobulus semilunaris 

superior) (0. T. posterior erescentic lobule). 
(ib) Inferior surface (fades inferior). 

(iba) Inferior semilunar lobule (lobulus semilunaris in- 
ferior) (0. T. postero-inferior lobule). 

(ibb) Slender lobule (lobulus gracilis). 

(ibc) Biventral lobule (lobulus biventer). 

(ibd) Tonsil of cerebellum (tonsilla cerebelli). 

(ibe) Flocculus (flocculus) ("wool-tuft-like body"). 

(1) Secondary flocculi (flocculi secundarii), in- 

constant. 

(2) Peduncle of flocculus (pedunculus -flocculi). 
(ibf) Nidus avis (nidus avis) ("bird's nest"). 



FIG. 148. 



Corpora quadrigemina 
Trigonum lemnisci 

Corpus geniculatum mediate,^ 

Pedunculus cerebri^ 
Brachium conjunctivum < ^j^' 
Brachium pontis,,_ 
Corpus restifonne .. 




Taenia ventriculi quarti 
Obex 

Tuberculum cuneatum- 

Tuberculum cinereum-- 

Clava- 

Funiculus cuneatus' 
Funiculus gracilis- 
Funiculus lateralis.. 



Commissura posterior cerebri 

,Locus caeruleus 

Eminentia medialis 

Sulcus longitudlnalis fossae 
rhomboideae 

,Fovea superior 



Colliculus facialis 
^ Striae medullares 

. Area acustica 

--Tuberculum acusticum 

Fovea inferior (ala cinerea) 
Eminentia medialis (trigonum 

n. hypoglossi) 
Calamus scriptorius 

Fissura mediana posterior 
Sulcus intermedius posterior 
Sulcus lateralis posterior 



The dorsal surface of the medulla oblongata and midbrain and the floor of the fourth ventricle The 
lum has been removed. (After Toldt, Anat. Atlas, Wien, 1903, 3 Aufl., p. 768, Fig. 1178.) 

Fourth Ventricle (Ventriculus quartus). 

(a) Rhomboid fossa (fossa rhomboidea). 

(aa) Inferior part (pars inferior fossae rhomboideae [calamus 
scriptorius]). 



DISSECTION OF THE HEAD AND NECK 331 

(ab) Intermediate part (pars intermedia fossae rhomb oideae) . 

(aba) Lateral recess (recessus lateralis fossae rhom- 
boideae). 

(ac) Superior part (pars superior fossae rhomb oideae) . 

(ad) Limiting groove (sulcus limitans [fossae rhomb oideae]) . 

(ada) Inferior pit (fovea inferior). 

(adb) Superior pit (fovea superior). 

(b) Trigone of hypoglossal nerve (trigonum N. hypoglossi). 

(c) Medullary striae (striae medullares) (0. T. striae acusticae). 

(d) Medial eminence (eminentia medialis) (0. T. eminentia teres). 

(e) Facial hillock (colliculus facialis). 

(f) Ash-like wing (ala cinerea) (0. T. trigonum vagi). 

(g) Acoustic area (area acustica) (0. T. trigonum acustici). 
(h) Locus caeruleus (locus caeruleus) ("blue place"). 

(i) Roof of fourth ventricle (tegmen ventriculi quarti). 

(ia) Posterior medullary velum (velum medullare posterius). 
(ib) Junction of epithelial part of roof with compact nerve sub- 
stance (taenia ventriculi quarti). 
(iba) Obex (pbex) ("bar"). 
(ic) Epithelial chorioid layer (lamina chorioidea epithelialis) . 

(ica) Median aperture (apertura mediana ventriculi 

quarti [foramen Magendii]). 
(icb) Lateral aperture (apertura lateralis ventriculi 

quarti). 
(id) Fastigium (fastigium) (" summit of roof "). 

External Morphology of Forebrain (Prosencephalon). 

Cut cautiously through the remaining cerebral peduncle and 
place the rhombencephalon and the mesencephalon in preserving 
fluid for further study later. In the prosencephalon distinguish 
the following parts : 

Forebrain (prosencephalon). 
Interbrain ( diencephalon) . 

Thalamic brain (thalamencephalon). 

Mammillary part of hypothalanms (pars mammillaris hypothalami). 
End-brain (telencephalon) . 

Hemisphere ( hemisphaerium ) . 

Optic part of hypothalamus (pars optica hypothalami). 

Make three drawings of the half of the prosencephalon before 
you 

(a) Of medial surface (fades medialis cerebri). (Fig. 151.) 

(b) Of convex surface (fades convexa cerebri). (Fig. 149.) 

(c) Of base (basis cerebri). (Fig. 150.) 

Take up systematically the study of the external morphology 
as follows : 



332 



LABORATORY MANUAL OF HUMAN ANATOMY 



End-brain (Telencephalon). 

Note that it consists of the optic part of the hypothalamus 
(pars optica hypothalami) and the hemisphere (hemisphaer- 
ium). 

Hemisphere (Hemisphaerium). 

This includes the brain-mantle (pallium), the olfactory brain 
(rhinencephalon) , and the striate body (corpus striatum). The 
fissura longitudinalis cerebri was examined before the hemi- 
spheres were separated. Locate now the transverse fissure of 
the cerebrum (fissura transversa cerebri). 

FIG. 149. 



Fissura 

parieto- 

occipitalis 



Gyrus frontal is \ 
inferior 




Pars orbitalis 
Pars triangularis 



Pars opercularis '.! 
Operculum 



The left cerebral hemisphere. Lateral aspect. (After Toldt, Anat. Atlas, Wien, 1903, 
3Aufl., p. 777, Fig. 1194.) 

Brain-mantle (Pallium). 

Note its subdivision by fissures (fissurae cerebri) and grooves 

(sulci cerebri) into convolutions (gyri cerebri). What is the 

fference arbitrarily made between a " fissure " and a " sul- 

cus"? Besides the main gyri, there are others in the depth 

(gyri profundi) and small gyri connecting adjacent gyri, the 

o-called gyri transitivi (0. T. annectent gyri). On the basis 

cerebri note the petrosal impression (impressio petrosa) due to 

the petrous portion of the temporal bone. 

The student should begin his study of the topography of the 
pallium with a careful examination of the lateral fissure of the 



DISSECTION OF THE HEAD AND NECK 



333 



cerebrum (fissura cerebri lateralis [Sylvii]), ordinarily known 
as the " fissure of Sylvius. " Besides its main trunk (truncus), 
observe 

(a) Posterior ramus (ramus posterior). 

(b) Ascending anterior ramus (ramus anterior ascendens). 

(c) Horizontal anterior ramus (ramus anterior horizontalis} . 



FIG. 150. 



Fissura longitudinalis cerebri, 

Polus frontalis \ 

Sulcus olfactorius 



Sulci orbitales 



Bulbus olfactorius 

,' _ Tractus olfactorius 



Polus temporalis 



Trigonum.^ 
olfactorium 



Chiasma opticum. 4-.- 7 *-- 




Fissura col- 
lateralis 



Sulcus tem^ 
ralis inferior 



Isthmus gyri fornicati'' 



Striae olfactoriae, medialis, 
intermedia, lateralis 

Substantia perforate 
anterior 



Limen insulae 

Fissura cerebri 
lateralis (Sylvii) 



Nucleus 
amygdalae 

Pedunculus 
cerebri (Basis 
pedunculi) 



-Substantia per- 
forata posterior 



Substantia 
nigra 



Tegmentum 



Aquseductus cerebri 

(Sylvii) 

Lamina quadrigemina 



Gyrus fornicatus 

Polus occipitalis 



Splenium corporis callosi 
Fissura longitudinalis cerebri 



Basal surface of the cerebrum. (After Toldt, Anat. Atlas, Wien, 1903, 3 Aufl., p. 775, Fig. 1191.) 



Lobes of Cerebrum (Lobi cerebri) and their Boundaries. 

The pallium has been subdivided arbitrarily into five lobes 

(1) Frontal lobe (lobus frontalis). 

(2) Parietal lobe (lobus parietalis). 

(3) Temporal lobe (lobus temporalis). 

(4) Occipital lobe (lobus occipitalis). 

(5) Island of Reil (insula). 



334 LABORATORY MANUAL OF HUMAN ANATOMY 

These five lobes are bounded by six fissures : 

(1) Fissure of Sylvius (fissura cerebri lateralis [Sylvii]). 

(2) Central sulcus of Rolando (sulcus centralis [Rolandi]) (0. T. fissure 

of Rolando). 

(3) Sulcus of cingulum (sulcus cinguli) (0. T. callosomarginal sulcus). 

(4) Parieto-occipital fissure (fissura parietooccipitalis) . 

(5) Collateral fissure (fissura collateralis}. 

(6) Circular sulcus of Reil (sulcus circularis [Reili]) (0. T. limiting 

sulcus of Reil). 

Frontal Lobe (Lobus frontalis). 

Find its posterior boundary on the convex surface by locating 
the sulcus centralis [Rolandi] ; the latter is always between the 
two parallel, obliquely placed, central gyri. What is the infe- 
rior boundary of the frontal lobe on the convex surface? How 
is it bounded on the medial surface of the hemisphere! In the 
frontal lobe study the following : 

(a) Frontal pole (polus frontalis). 

(b) Anterior central gyrus (gyrus centralis anterior}. 

(c) Precentral sulcus (sulcus praecentralis) . 

(d) Superior frontal gyrus (gyrus frontalis superior). 

(e) Superior frontal sulcus (sulcus frontalis superior). 

(f) Middle frontal gyrus (gyrus frontalis medius). 

(fa) Superior part (pars superior). 

(fb) Inferior part (pars inferior). 

(g) Inferior frontal sulcus (sulcus frontalis inferior), 
(h) Inferior frontal gyrus (gyrus frontalis inferior). 

(ha) Opercular part (pars opercularis) (on the left side this con- 
stitutes the celebrated Broca's convolution, concerned in the 
function of speech). 

(hb) Triangular part (pars triangularis). 
(he) Orbital part (pars orbitalis). 
(i) Straight gyrus (gyrus rectus). 
(j) Olfactory sulcus (sulcus olfactorius) . 
(k) Orbital gyri (gyri orbitales). 
(I) Orbital sulci (sulci orbitales). 

Parietal Lobe (Lobus parietalis). 
How is it bounded 

(a) On the convex surface? 

(b) On the medial surface? 

Examine on the convex surface 

(a) Posterior central gyrus (gyrus centralis posterior) (0. T. ascending 
parietal convolution). 



DISSECTION OF THE HEAD AND NECK 335 

(b) Interparietal sulcus (sulcus inter parietalis) (0. T. intraparietal 

sulcus of Turner). Note the sulcus paroccipitalis of Wilder, 

(c) Superior parietal lobule (lobulus parietalis superior). 

(d) Inferior parietal lobule (lobulus parietalis inferior). 

(da) Supramarginal gyrus (gyrus supramarginalis) around end 

of fissure of Sylvius. 

(db) Angular gyrus (gyrus angularis), around end of sulcus tem- 

poralis superior. 

The portion of the parietal lobe on the medial surface of the 
hemisphere will be studied later. 

Occipital Lobe (Lobus occipitalis). 
How is it bounded 

(a) On the convex surface? 

(b) On the medial surface? 

On the convex surface, examine 

(a) Transverse occipital sulcus (sulcus occipitalis transversus). 

(b) Superior occipital gyri (gyri occipitales superiores). 

(c) Superior occipital sulci (sulci occipitales superiores}. 

(d) Lateral occipital gyri (gyri occipitales laterales). 

(e) Lateral occipital sulci (sulci occipitales laterales). 

Locate the occipital pole (polus occipitalis). 

The medial surface of the occipital lobe will be studied later. 

Temporal Lobe (Lobus temporalis). 

What are its boundaries! Observe the temporal pole (polus 
temporalis). Examine the following: 

(a) Transverse temporal sulci (sulci temporales transversi). 

(b) Transverse temporal gyri (gyri temporaleb transversi). 

(c) Superior temporal gyrus (gyrus temporalis superior) (0. T. first tem- 

poral gyrus). 

(d) Superior temporal sulcus (sulcus temporalis superior) (0. T. parallel 

sulcus, or first temporal sulcus). 

(e) Middle temporal gyrus (gyrus temporalis medius) (0. T. second tem- 

poral gyrus). 

(/) Middle temporal sulcus (sulcus temporalis medius) (0. T. second 
temporal sulcus). 

(g) Inferior temporal gyrus (gyrus temporalis inferior) (0. T. third tem- 
poral gyrus). 

(h) Inferior temporal sulcus (sulcus temporalis inferior) (0. T. occipito- 
temporal sulcus). 

(i) Fusiform gyrus (gyrus fusiformis) (0. T. occipitotemporal convo- 
lution). 

(j) Lingual gyrus (gyrus lingualis). In some English books this is re- 
garded as a part of the occipital rather than of the temporal lobe. 



336 



LABORATORY MANUAL OF HUMAN ANATOMY 



Medial Surface of Hemisphere (Facies medialis hemisphaerii). 
Here study 

(a) Sulcus of corpus callosum (sulcus corporis callosi) (0. T. callosal 

sulcus). , 

(b) Fissure of hippocampus (fissura hippocampi) (0. T. dentate fissure, 

or fissura dentata) (between gyrus hippocampi and fascia den- 
tata). 

(c) Fornicate gyrus (gyrus fornicatus) (0. T. limbic or falciform lobe). 

(ca) Gyrus of cingulum (gyrus cinguli) (0. T. callosal convolu- 

tion, or gyrus fornicatus). 

(cb) Gyrus of hippocampus (gyrus hippocampi] (0. T. hippo- 

campal convolution). 
(cba) Hook of gyrus hippocampi (uncus gyri hippocampi] 

(0. T. uncinate gyrus). 
(ebb) White reticular substance of Arnold (substantia 

reticularis alba [Arnoldi] ) . 

(cc) Isthmus of fornicate gyrus (isthmus gyri fornicati). 



FIG. 151. 



Sulcus cinguli (pars marginalis) 
Sulcus subparietalis 
Fissura parieto- 
occipitalis 



Sulcus cinguli (pars subfrontalis) 
Sulcus corporis collosi 



calcarina 




Genu corporis callosi 
Rostrum corporis callosi 
\ \ Sulcus parolfactorius anterior 
\ Area parolfactoria (Brocse) 
Sulcus parolfactorius posterior 
Gyrus subcallosus (Pedunculus 
corporis callosi) 

The left cerebral hemisphere. Medial aspect. (After Toldt, Anat. Atlas, Wien, 1903, 3 Aufl., 

p. 777, Fig. 1195) 

(d) Sulcus of cingulum (sulcus cinguli) (0. T. callosomarginal fissure). 

(da) Subf rental part (pars subfrontalis). 

(db) Marginal part (pars marginalis). 

(e) Subparietal sulcus (sulcus subparietalis). 

(f) Paracentral lobule (lobulus paracentralis) . This belongs to the 

frontal lobe. 

(g) Precuneus (praecuneus) . This belongs to the parietal lobe. 



DISSECTION OF THE HEAD AND NECK 337 

(h) Parieto-occipital fissure (ftssura parietooccipitalis) . 

(i) Cuneus (cuneus) ("wedge"). This belongs to the occipital lobe. 

(j) Calcarine fissure (ftssura calcarina). 

Island (Insula) (O. T. Island of Reil, or Central Lobe). 

Pull the lips of the Sylvian fissure apart and examine the 
island. If possible, study the island on a fresh brain or on one 
prepared especially to show the island. How is it bounded! 
Examine carefully the overhanging operculum, and note that it 
is subdivisible into a frontal part (pars frontalis), a parietal 
part (pars parietalis), and a temporal part (pars temporalis). 
In the island study 

(a) Sulci of island (sulci insulae). 

(b) Gyri of island (gyri insulae). 

(ba) Long gyrus of island (gyrus longus insulae). 

(bb) Short gyri of island (gyri breves insulae). 

Olfactory Brain (Rhinencephalon). (Vide Fig. 151.) 
Examine 

(a) Anterior parolfactory sulcus (sulcus parolfactorius anterior). 

(b) Anterior part of rhinencephalon (pars anterior [rhinencephali]). 

(ba) Olfactory lobe (lobus olfactorius) . 

(baa) Olfactory bulb (bulbus olfactorius). 

(bab) Olfactory tract (tractus olfactorius) (incorrectly 

sometimes designated "olfactory nerve"). 

(bac) Olfactory trigone (trigonum olfactorium) . 

(bad) Medial stria (stria medialis). 

(bae) Intermediate stria (stria intermedia). 

(bb) Parolfactory area of Broca (area parolfactoria [Brocae]). 

(c) Posterior parolfactory sulcus (sulcus parolfactorius posterior). 

(d) Posterior part of rhinencephalon (pars posterior [rhinencephali]). 

(da) Subcallosal gyrus (gyrus subcallosus [pedunculus corporis 

callosi] ) . 

(daa) Anterior perforated substance (substantia perforata 
anterior). 

(db) Lateral olfactory stria (stria olfactoria lateralis). 

(dc) Threshold of island (limen insulae). 

Note that, in the broader sense, the gyrus fornicatus, fimbria 
and fascia dentata hippocampi, fornix, and corpora mammilla- 
ria are often classed as belonging to the rhinencephalon. In the 
fissura hippocampi note the fimbria hippocampi and the fascia 
dentata hippocampi (O. T. gyrus dentatus), lying side by side. 
The handle of the scalpel shoved deeply into the brain just above 
the fimbria would enter the inferior cornu of the lateral ventricle. 

22 



338 LABORATORY MANUAL OF HUMAN ANATOMY 

Hypothalamus (O. T. Subthalamic Region). 
Note that it is subdivisible into 

(a) Mammillary part of hypothalamus (pars mammillaris hypothalami). 

This belongs to the diencephalon and includes 
(aa) Mammillary body (corpus mammillare) on each side. 

(b) Optic part of hypothalamus (pars optica hypothalami). This belongs 

to the telencephalon and includes 

(ba) Tuber cinereum (tuber cinereum) (" ash-like tuber" ). 

(bb) Infundibulum (infundibulum) ("funnel"). 

(be) Hypophysis (0. T. pituitary body). Cut through this in the 
median sagittal plane and note 

(bca) Anterior lobe (lobus anterior), from the hypoblast. 

(bcb) Posterior lobe (lobus posterior), from the epiblast. 

(bd) Optic tract (tractus opticus). 

(bda) Medial root (radix medialis). 
.(bdb) Lateral root (radix lateralis). 

(be) Optic chiasm (chiasma opticum). 

(bf) Terminal lamina (lamina terminalis). 

Corpus Callosum (Great Transverse Commissure of Cerebrum). 

With a sharp, thin, broad brain-knife, the upper part of the 
right hemisphere should be sliced off at the level of the sulcus 
cinguli. The cortical substance (substantia corticalis) and semi- 
oval centre (centrum semiovale) of the hemisphere are thus 
beautifully displayed. Cut transversely through the middle of 
the gyrus cinguli; insinuate the fingers cautiously beneath it 
and tear it away lateralward, observing how the fibres of the 
corpus callosum enter the hemisphere. These fibres constitute 
the radiation of the corpus callosum (radiatio corporis callosi). 
This radiation is subdivisible into a frontal part (pars front alls] 
(0. T. forceps minor), a parietal part (pars parietalis), a tem- 
poral part (pars temporalis), an occipital part (pars occipi- 
talis) (0. T. forceps major), and the " tapestry" (tapetum), the 
layer of fibres coming from the truncus corporis callosi and 
curving lateralward and downward over the inferior and poste- 
rior horns of the lateral ventricle. In the gyrus cinguli, just 
torn away, note on the deep surface a very definite bundle of 
sagittally directed arcuate fibres, easily lifted out of the bed in 
which it lies. This is the cingulum or "girdle," an association 
bundle pertaining to the rhinencephalon. (See full description 
in Barker's Nervous System, p. 1061.) Examine 

(a) Splenium ("bandage") of corpus callosum (splenium corporis cal- 

losi). 

(b) Trunk of corpus callosum (truncus corporis callosi) (0. T. body). 

(c) Knee of corpus callosum (genu corporis callosi). 



DISSECTION OF THE HEAD AND NECK 



339 



(d) Beak of corpus callosum (rostrum corporis callosi). 

(da) Rostral lamina (lamina rostralis). 

(e) Transverse striae (striae transversae) . 

(f) Medial longitudinal stria (stria longitudinalis medialis). 

(g) Lateral longitudinal stria (stria longitudinalis lateralis). 

(h) Fasciola cinerea (fasciola cinerea) ("ash-like little bandage"). 

Lateral Ventricle (Ventriculus lateralis). 

Make a sagittal incision through corpus callosum one centi- 
metre from sagittal median plane; the part of the corpus cal- 
losum lateral from the incision is to be reflected lateral ward and 
removed; leave the part of the corpus callosum medial from 
the incision in place. Note the relation of the splenium corporis 

FIG. 152. 



Cornu anterius 

Foramen interventriculare [Monroi] 
Ventriculus tertius 

..Cornu inferius 
Aquaeductus cerebri [SylviiJ 

Ventriculus quartus 
.Cornu poster! us 



Cast of the ventricles. (After Welcker.) (From Poirier et Charpy, Traite d'Anat. hum., Paris, 1901, 

2ed., t. iii., 1, p. 365, Fig. 260.) 

callosi to the pars occipitalis of the radiatio corporis callosi, or 
forceps major; leave the latter in place. 

The central part and anterior cornu of the lateral ventricle 
are now exposed. Make a cut backward and lateralward through 
the white matter which forms the roof of the posterior horn and 
excise enough of this roof to permit of thorough inspection of 
the cavity. To open the inferior horn, place the tip of the knife 
in the central part of the ventricle at the entrance to the inferior 
horn and make a cut downward and forward through the outer 
part of the temporal lobe towards the polus temporalis, following 
the course of the inferior horn, which runs nearly parallel to 
the sulcus temporalis superior. Now remove the part of the 




340 



LABORATORY MANUAL OF HUMAN ANATOMY 



temporal lobe above this incision, including the pars temporalis 
of the operculum ; take care not to injure the island. 

Observe the general form, and study the walls, of the various 
subdivisions of the lateral ventricle ; compare your observations 
with atlases, models, and text-book descriptions. 



FIG. 153. 



Genu corporis callosi 
Septum pellucidum 

Cornu anterius ventriculi 
lateralis 

Columna fornicis v 

Commissura anterior^ 
(cerebri) 

Polus temporalis - 
Nucleus amygdalae 
Digitationes hippocampi 
Uncus _ 

Cornu inferius ven- 
triculi lateralis 

Ventriculus tertius 

Hippocampus - 
Fimbria hippocampi 

Fascia dentata hippocampi 

Radiatio corporis callosi 
(pars temporalis) 

Calcar avis 

Cornu posterius ventriculi 
lateralis 

Cerebellum (vermis superior) 




atum (caput) 
Kecessus triangularis 



Tuberculum anterius 
< thalami 



Taenia chorioidea 



Massa intermedia 
tertii 



Stria medullaris 
thalami 



Commissura 
habenularum 



.Trigonum 
habenulae 



~r~-f - Hippocampus 



Habenula 
Corpus pineale 
Trigonum collaterale 

Eminentia collateralis 
Tapetum 



Corpora quadrigemina 



The ventricles of the brain shown completely opened from above. The upper part of the cerebral 
hemispheres, the corpus callosum, the fornix, and the tela chorioidea have been removed, and the 
corpora quadrigemina, corpus pineale, and vermis superior laid bare. (After Toldt, Anat. Atlas, Wien, 
1903, 3 Aufl., p. 782, Fig. 1200.) 

(a) Head of caudate nucleus (caput nuclei caudati). 

(b) Anterior horn (cornu anterius). 

(c) Posterior horn (cornu posterius). 

(d) Inferior horn (cornu inferius) (0. T. descending horn). 

In the anterior horn study 

(a) Head of caudate nucleus (caput nuclei caudati). 

In the central part of the ventricle study 



DISSECTION OF THE HEAD AND NECK 



341 



(a) 

(6) 
(c) 

(d) 



(e) 



(9) 
(h) 

(*) 



Caudate nucleus (nucleus caudatus). 

Terminal stria (stria terminalis) (0. T. taenia semicireularis). 

Terminal vein (vena terminalis) (0. T. vein of the corpus striatum). 

Lamina affixa (lamina affixa) ("fastened layer"). 

(The embryology of the part must be studied, in order to under- 
stand the origin of this structure.) 

Chorioid plexus of lateral ventricle (plexus chorioideus ventriculi lat- 
eralis ) . 

Epithelial chorioid layer (lamina chorioidea epithelialis). 

Chorioid taenia (taenia chorioidea). 

Thalamus (thalamus) (showing through). 

Taenia of fornix (taenia fornicis) (0. T. sharp edge of fornix). 

FIG. 154. 




Transverse section through the tela chorioidea, ventriculi tertii, and adjacent parts. 
II, lateral ventricle ; III, third ventricle ; Cc, corpus callosum ; F, fornix ; Th, thalamus ; St. TO, 
stria medullaris ; St. t, stria terminalis ; V. t, vena terminalis ; L, lamina affixa ; 1, taenia thalami ; 2 , 
taenia chorioidea ; 3, taenia fornicis. The figure shows the continuity of the taeniae and the epithelial 
layer of the plexus chorioidea. (After His, Die Anat. Nomenclatur, Leipzig, 1895, p. 166, Fig. 21.) 

In the posterior horn of the ventricle study 

(a) Roof and lateral wall formed by tapetum. 

(b) Two ridges on medial wall. 

(ba) Upper ridge = bulb of posterior horn (bulbus cornu poste- 
rioris), due to pars occipitalis of radiatio corporis callosi, 
the so-called " forceps major/' hooking around the fissura 
parieto-occipitalis. 

(feb) Lower ridge = calcar avis (calcar avis) (" cock's spur") (0. 
T. hippocampus minor), due to fissura calcarina. 

Before studying the inferior horn of the ventricle in detail, 
insert the fingers cautiously beneath the pars frontalis and pars 
parietalis of the operculum of the island, and tear away the 
cortex. This exposes the island thoroughly, and its relations to 
the lateral ventricle can be examined. 

In the inferior horn of the ventricle study 

(a) Its narrow inferior wall. 

(aa) Collateral eminence (eminentia collateralis) , corresponding 
to the fissura collateralis ; it is sometimes absent. 



342 LABORATORY MANUAL OF HUMAN ANATOMY 

(aaa) Collateral trigone (trigonum collaterale) (0. T. 

trigonum ventriculi). 
(b) Its lateral and superior walls. 

(ba) Tapetum. 

(bb) Lowermost end of striate body (corpus striatum). 

(be) Swelling due to amygdaloid nucleus (nucleus amygdalae). 

(bd) Terminal stria (stria terminalis). 

(be) Tail of caudate nucleus (cauda nuclei caudati). 




Section through the base of the brain and the hippocampus lying beneath it. Plexus chorioideus 
made ampler than the actual. . (After L. Edinger, Nervose Centralorgane, V. Aufl., Leipzig, 1896, S. 225. 

(c) Its medial wall. 

(ca) Hippocampus (hippocampus) ("sea-horse") (0. T. hippo- 
campus major, cornu Ammonis, or Ammon's 
horn). It corresponds to the fissura hippocampi 
of the facies medialis hemisphaerii. 

(caa) Digitations of the hippocampus (digitationes hip- 
pocampi) (0. T. pes hippocampi). 



DISSECTION OF THE HEAD AND NECK 343 

(cb) Chorioid plexus (plexus chorioideus ventriculi lateralis). The 
fimbria hippocampi and fascia dentata hippocampi have 
already been examined. The edge of the fimbria after 
tearing away the .chorioid plexus is called the taenia fim- 
briae. 

The student should next remove the remains of the right 
temporal and occipital lobes ; cut through (a) the fimbria hippo- 
campi, where it passes into the crus fornicis, and (b) the occipi- 
tal part of the radiation of the corpus callosum (0. T. forceps 
major). Next make an incision from the anterior end of the 
cornu inferius forward, above the level of the uncus, through the 
polus temporalis. Now separate the lobus temporalis, with the 
gyrus hippocampi medial to it, from the rest of the hemisphere, 
the separation taking place along the line of the inferior part of 
the fissura transversa cerebri. Cut away enough of the lateral 
edge of the remaining medial part of the corpus callosum to 
permit of a good view of the septum pellucidum and the f ornix, 
lying beneath it. Having noted their relations, cut across the 
remains of corpus callosum behind the genu, gently raise the 
truncus corporis callosi, and dissect backward, freeing it from 
the septum pellucidum and, further back, from the fornix. 

Septum pellucidum. 

(a) Layer of septum pellucidum (lamina septi pellucidi). 

(b) Cavity of septum pellucidum (cavum septi pellucidi) (0. T. fifth 

ventricle). 
Fornix. 

(a) Body of fornix (corpus fornicis). 

(aa) Taenia of fornix (taenia fornicis). 

(b) Crus of fornix (crus fornicis) (0. T. posterior pillar of fornix). 

(c) Column of fornix (columna fornicis) (0. T. anterior pillar of 

fornix). 

(ca) Free part (pars libera columnae fornicis). 

(cb) Covered part (pars tecta columnae fornicis). 

Next cut transversely through the corpus fornicis at its 
middle and gently reflect the two ends forward and backward 
respectively. Running medialward from the crus fornicis, infe- 
rior to the corpus callosum, towards the crus fornicis of the 
opposite side, observe the commissure of the hippocampus 
(commissura hippocampi) (0. T. lyra or lyre of David). The 
space between the commissura hippocampi and the inferior sur- 
face of the corpus callosum has been called " Verga's ventricle. " 
One-half of the so-called chorioid tela of the third ventricle (tela 
chorioidea ventriculi tertii) (0. T. velum interpositum) is now 



344 



LABORATORY MANUAL OF HUMAN ANATOMY 



exposed; note how it is formed by the pia mater encephali 
coming in through the fissura transversa cerebri. In connection 
with it, study 

(a) Upper lamella, next to inferior surface of corpus callosum and fornix. 

(b) Lower lamella, over the surface of the thalamus. 

(c) Between (a) and (b) some loose connective tissue, a continuation of 

the subarachnoideal connective tissue of the cisterna venae 
cerebri magnae. In this study 



FIG. 156. 



Cq* Cq 



Ccq 



Gcb 




Co 



II' 



Spa 



A portion of the right cerebral hemisphere resting on the polus frontalis, to illustrate the basis cerebri. 
Sea, brachium quadrigeminum superius ; Bcp, brachium quadrigeminum inferius ; Ccb, pedunculus 
cerebri ; Cgl, corpus geniculatum laterale ; Cgm, corpus geniculatum mediale ; Ccq, brachium conjunc- 
tivum ; Co, chiasma opticum ; Cq 1 , colliculus inferior ; Cqi, colliculus superior ; L, lemniscus ; Pv, pul- 
vinar of thalamus ; Spa, substantia perforata anterior ; St, stria terminalis ; II', tractus opticus. The 
radix medialis and the radix lateralis are well illustrated ; f, cut surface of tip of temporal lobe which 
has been removed. (After J. Henle, Handbuch der Nervenlehre des Menschen, II. Aufl., Braunsch.. 
1879, S. 155, Fig. 80.) 

(ca) The two internal veins of the cerebrum (venae cerebri inter- 
nae) (0. T. veins of Galen), and their tribu- 
taries 

(caa) Vein of septum pellucidum (V. septi pellucidi). 

(cab) Terminal vein (V. terminalis) (0. T. vein of the 

corpus striatum). 

(cac) Chorioid vein (V. chorioidea). 

The venae cerebri internae unite to form the 



DISSECTION OF THE HEAD AND NECK 



345 



large vein of the cerebrum (vena magna cerebri 
[Galeni]), which in turn opens into the straight 
sinus (sinus rectus). 

(d) Chorioid plexus of lateral ventricle (plexus chorioideus ventriculi lat- 
eralis ) . 



Pul 




Po 



Isthmus rhombencephali seen in profile. 

BIT, tractus opticus ; BrQa, brachiura quadrigeminum superius ; BrQp, brachium quadrigeminum 
inferius ; Cge, corpus geniculatum laterale ; Cgi, corpus geniculatum mediale ; Chll, chlasma opticum ; 
Crst, corpus restiforme ; Fla, funiculus lateralis of medulla oblongata ; Jaa, fibrae arcuatae externae ; 
Fob, fibrae superficiales pontis ; Cp, corpus pineale ; Nil, N. opticus ; Oi, oliva ; P, pedunculus cerebri ; 
Pern, brachium pontis; PCS, brachium conjunctivum; Po, pons Varoli ; Pul, pulvinar; Py, pyramis; 
Qa, colliculus superior; Qp, colliculus inferior; SI, trigonum lemnisci; Rm, lemniscus medialis; si, 
sulcus lateralis; Th, thalamus; Tpo, taenia pontis; Tpt, tractus peduncularis transversus. (After J. 
D6jerine, Anatomic des centres nerveux, t. i., Paris, 1895, p. 328, Fig. 192.) 



(da) Chorioid skein (glomus chorioideum) . 

Now cut through the V. terminalis at its junction with 
the V. cerebri interna, seize the apex of the right half of 
the tela chorioidea ventriculi tertii, and pull it with the 
chorioid plexuses backward, but be careful not to tear away 
the corpus pineale beneath it behind. Examine 

(e) Chorioid plexus of third ventricle (plexus chorioideus ventriculi 
tertii) . 



346 LABORATORY MANUAL OF HUMAN ANATOMY 

Thalamencephalon. 

This part of the diencephalon includes (1) the thalamus, (2) 
the metathalamus, and (3) the epithalamus. 

Thalamus (O. T. Optic Thalamus). 

The upper and medial surfaces of the thalamus may now be 
examined. Observe 

^a) Pulvinar (pulvinar) ("cushion"). 

(b) Anterior tubercle of the thalamus (tuberculum anterius thalami). 

(c) Medullary stria (stria medullaris) (0. T. stria fornicis or stria pine- 

alis). 

(d) Epithelial chorioid layer (lamina chorioidea epithelialis) . 

This covers the thalamus where it appears to be, but is not, in 
the lateral ventricle. 

Metathalamus. 

Behind and beneath the thalamus observe 

(a) Medial geniculate body (corpus geniculatum mediale) (0. T. internal 

geniculate body). This has to do chiefly with the auditory conduc- 
tion path. 

(b) Lateral geniculate body (corpus geniculatum laterale) (0. T. external 

geniculate body). This has to do with the visual conduction path. 

Epithalamus. 

Here the student should study 

(a) Pineal body (corpus pineale) (0. T. conarium, or epiphysis cerebri). 

(b) Pineal recess (recessus pinealis). 

(c) Suprapineal recess (recessus suprapinealis) . 

(d) Habenula (0. T. peduncle of the pineal body). 

(e) Commissure of the habenulae (commissura habenularum) . 

(f) Trigone of the habenula (trigonum habenulae). 

Third Ventricle (Ventriculus tertius). 

This has been cut in two in the median plane, and its roof, 
tela chorioidea ventriculi tertii, with the lamina chorioidea epi- 
thelialis, has been removed. The student should now study the 
following structures and openings : 

(a) Entrance to the aqueduct of the cerebrum (aditus ad aquaeductum 

cerebri). 

(b) Posterior commissure of the cerebrum (commissura posterior [cere- 

bri]) (above the aditus ad aquaeductus cerebri). 

(c) Interventricular foramen of Monro (foramen interventriculare [Mon- 

roi]). One on each side, connecting ventriculus tertius with ven- 
triculus lateralis. 



DISSECTION OF THE HEAD AND NECK 



347 



(d) Hypothalamic sulcus of Monro (sulcus hypothalamicus [Monroi]). 

Note the importance of this in connection with the embryology of 
the brain. Compare with the sulcus limitans in the floor of the 
fourth ventricle. 

(e) Intermediate mass (massa intermedia) (0. T. middle or soft or gray 

commissure). 
(/) Optic recess (recessus opticus). (Cf. W. His's models of developing 

brain.) 

(g) Recess of infundibulum (recessus infundibuli) . 
(h) Anterior commissure of cerebrum (commissura anterior [cerebri]). 
(i) Triangular recess (recessus triangularis) . 



SECTIONS THROUGH BRAIN (SECTIONES 
ENCEPHALI). 

Sections of Medulla Oblongata (Sectiones medullae oblongatae). 

Make three transverse sections through the medulla oblon- 
gata: (1) at the level of the decussation of the pyramids; (2) 
between the decussation of the pyramids and the olives; (3) 

FIG. 158. 

Fissura mediana posterior 
Nucleus fasciculi gracilis 



Nucleus fasciculi cuneati 



Nucleus tract-, 
spinal is N. tri 
gemini 



Formatio reticularis- 




Fasciculus gracilis [Golli] 

Fasciculus cuneatus [Burdachi] 



Secondary trigeminal path 

Tractus spinalis 
N. trigemini 



Fasciculus cere- 
bellospinalis 

Fila radicularia 
N. accessorii 



Gowers' tract and the 
tract to the lateral 

funiculus from 
Deiters' nucleus and 
from the red nucleus 



Fasciculus longitudinalis medialis 



Columna anterior 
Substantia grisea centralis 

Decussatio pyramid um Pyramis [medullae oblongatae] 

Transverse section of the brain-stem of an adult, through the decussation of the pyramids. Magnifica- 
ation : 6 : 1. (After Spalteholz, Hand Atlas of Hum. Anat., Leipzig, 1903, vol. iii., p. 656, Fig. 725.) 

through the middle of the olives. (Cf. Spalteholz, Fig. 723.) 
Examine first the unstained cross-sections and subsequently sec- 
tions, from the same levels, stained by Weigert's method. 1 Use 

1 The study is much simplified if sections through the brain-stem of a new- 
born babe are used; see Figs. 162-169. 



348 



LABORATORY MANUAL OF HUMAN ANATOMY 



a hand-lens or dissecting microscope, 
eating- 



Make drawings indi- 



(1) Median raphe (raphe). 

(2) Nuclear layer (stratum nuclear e}. 

(3) Nucleus of hypoglossal nerve (nucleus N. hypoglossi). 

(4) Ambiguous nucleus (nucleus ambiguus). 

(5) Nucleus of ala cinerea (nucleus alae cinereae). 

(6) Solitary tract (tractus solitarius) (0. T. respiratory bundle). 

(a) Nucleus of solitary tract (nucleus tractus solitarii). 



FIG. 159. 



Nucleus fasciculi gracilis 
Ganglion commissurale alae cinereae 

Nucleus fasciculi cuneati 



Substantia grisea 
centralis 



Nucleus tractus 
spinalis N. 
trigemini 



Formatio reticu - 
laris 



Fissura mediana posterior 

Fasciculus gracilis [Golli] 

Fasciculus cuneatus [Burdachi] 



Secondary trigeminal 
path 



..Tractus spinalis 
" N. trigemini 



Tuberculum 
cinereum 



. . Fasciculus cere- 
bellospinalis 




Fibrae arcuatae internae j 

Fissura mediana anterior 



Columna anterioT^^H& . i$^J \ Cowers' tract and the 

tract to the lateral 

funiculus from 
Deiters' nucleus and 
from the red nucleus 
Fila radicularia N. cervicalis I 

v 

\ Fasciculus longitudinalis medialis 

Pyramis [medullare oblongatae] 
Decussatio lemniscorum 

Transverse section through the brain-stem of an adult, between the decussation of the pyramids 
the olives. Magnification: 6:1. (Held.) (After Spalteholz, Hand Atlas of Hum. Anat., Leipzig, 
j.yuo, vol. ill., p. boo, .tig. 726.) 

(7) Spinal tract of trigeminal nerve (tractus spinalis N. trigemini) (0. 

T. ascending root of trigeminal nerve a very bad name, 
for the fibres descend). 

(a) Nucleus of spinal tract of trigeminal nerve (nucleus tractus 
spinalis N. trigemini). 

(8) Nucleus of slender funiculus (nucleus funiculi gracilis) (0. T. nu- 

cleus of Goll's column). 

Nucleus of wedge-shaped funiculus (nucleus funiculi cuneati) (0. T. 
nucleus of Burdach's column). 

(10) Lateral nuclei (nuclei laterales). 

(11) Inferior olivary nucleus (nucleus olivaris inferior). 

(a) Hilus of olivary nucleus (hilus nuclei olivaris). 

(b) Medial accessory olivary nucleus (nucleus olivaris accessorius 

medialis). 



(9) 



DISSECTION OF THE HEAD AND NECK 



349 



FIG. 160. 

Area acustica Taenia ventriculi quarti 

Tractus solitarius *' Nucleus N. vestibularis medialis [Schwalbe] 
Nucleus tractus solitarii \ \\\ Kadix dyscend..!.^ X. v.-stibularis 

\ \ U Fila radicularia N. glossopharvngei 
Alacinerea.\ 
Nucleus alae cinereae ' 
Trigonum N. hypoglossi 



Sulcus medianus fossae ^ t 

rhomboideae 
Nucleus N. hy 



Fasciculus longitudinalis 

medialis 

Snbstantia reticularis grisea 
(Nucleus lateralis inferior) 

Substantia reticularis alba 
Fibrae cerebello-olivares ._. 
Fila radicularia - 
N. hypoglossi 

Stratum interolivare ^ 
lemnisci 



Raphe 



Fibrae arcuatae externae 
(to the corpus restiforme) " 



Nucleus arcuatus 
Pyramis [medullae oblongatae] 




Nucleus tractus spinalis N. trigemini 



^Corpus restiforme 



.Tractus spinal is 
N. trigemini 



Lateral areas of the for- 

matio reticularis 
la radicularia N. vagi 
.Nucleus ambiguus 

.Growers' tract and the tract to the 
'' lateral funiculus from Deiters' 
nucleus and from the red nucleus 
Nucleus olivaris accessories 
dorsal is 



"-.Fibrae arcuatae externae 



^ x -Hilus nuclei olivaris 



\ N. hypoglossus 
Nucleus olivaris inferior 

Nucleus olivaris accessorius medialis 



Transverse section of the brain-stem of an adult through the middle of the olive. Magnification : 4.5 : 1 
(Held. ) (After Spalteholz, Hand Atlas of Hum. Anat., Leipzig, 1903, vol. iii., p. 657, Fig. 727.) 



FIG. 161. 
Nu.com. 



F.c.toEr. 




Transverse section through medulla oblongata of new-born child at level of decussatio lemnis- 
corum. (Series ii. section No. 50.) 1 

C.c., canalis centralis ; Dec.l., decussatio lemniscorum ; F.a.i., fibrae arcuatae internae ; F.a.e., fibrae 
arcuatae externae ; .F.c., fasciculus cuneatus Burdachi ; F.c. to F.r., bundles from fasciculus cuneatus to 
formutio reticularis ; F.ds., fasciculus cerebellospinalis or direct cen-bellnr tract ; F.g., fasciculus gracilis 
Golli ; F.v.p., fasciculus ventralis proprius ; .\ti.<-in., nucleus commissuralis ; Xit.f.c., nucleus funiculi 
cuneati et gracilis ; A>/./.<y., nucleus funiculi grucilis : /'//., pyramis : T.n.n. I'.. tnu-tusspinnlisN. trigemini; 
S.g., substantia gelatinosa [Rolandi]. (From Barker, The Nerv. Syst., New York, 1899, p. 479, Fig. 308.) 



1 Figs. 161-169 are from Weigert-Pal preparations by Dr. John Hewetson. 



FIG. 162. 




Transverse section of medulla oblongata of new-born child passing through the nucleus olivaris 
inferior. (Series ii. section No. 102.) 

C.r., corpus restiforme ; -F.a.c., fibrae arcuatae internae from the anterior half of the nucleus funiculi 
cuneati; F.l.m., fasciculus longitudinalis medialis ; N.IX.X., N. glossopharyngeus et vagus; N.XII., N. 
hypoglossus ; NUM., nucleus arcuatus ; Nu.a.c., nucleus alae cinereae ; NuJ.c., nucleus funiculi cuneati ; 
Nu.o.a.m., nucleus olivaris accessorius medialis; Xu.o.i., nucleus olivaris inferior; Nu.n.XIL, nucleus 
N. hypoglossi; Py., pyramis ( non-medulla ted ); S.g., substantia gelatinosa Rolandi; St.i.l., stratum 
interolivare lemnisci ; T.s., tractus solitarius; T.s.n. V., tractus spinalis N. trigemini ; V. q., ventriculus 
quartus. (Weigert-Pal preparation by Dr. John Hewetson.) (From Barker, The Nerv. Syst., New York, 
1899, p. 479, Fig. 309.) 

FIG. 163. 




OA.ni 



Transverse section of medulla oblongata and cerebellum of new-born child. (Series ii. section No. 146.) 
C.r., corpus restiforme (the part medullated corresponds in the main to the direct cerebellar tract) ; 

F.I., bundle continuous with the funiculus lateralis of the cord; F.l.m., fasciculus longitudinalis 

medialis; X.IX.X., N. glossopharyngeus et vagus; N.XII., N. hypoglossus; Nu.d., nucleus dentatus ; 

Nu.n.e.d., nucleus N. cochleae dorsalis; Nu.n.v.m., nucleus N. vestibuli medialis; Nu.o.a.d., nucleus 

livaris accessorius dorsalis; Xu.o.a.m., nucleus olivaris accessorius medialis; Nu.o.L, nucleus olivaris 

iferior; Nu.t.s., nucleus tractus solitarii ; P/., pedunculus fiocculi ; Py., pyramis; R.d.n.vest., radix 

cendens N. vestibuli ; St.i.l., stratum interolivare lemnisci ; 66, plane of longitudinal section No. G6. 

[\ OT ,.:._ This figure has been disproportionately reduced in the reproduction.] (From Barker, The 

X< TV. Syst., New York, 1899, p. 480, Fig. 310.) 



DISSECTION OF THE HEAD AND NECK 



351 



FIG. 164. 




< 9 Sc 2 < 5. 3 sr a , -^ 

f^lt'tHMI 



sa- 2)3 

* >> 3 2- 

^ ? e 



S-f ill I .? 11.^1^ 



352 



LABORATORY MANUAL OF HUMAN ANATOMY 

(c) Dorsal accessory olivary nucleus (nucleus olivaris accessorius 
dorsalis). 

(12) Arcuate nuclei (nuclei arcuati). 

(13) Internal arcuate fibres (fibrae arcuatae internae). 

(14) Gray reticular substance (substantia reticularis grisea). 

(15) White reticular substance (substantia reticularis alba). 

FIG. 165. 




NYttPIIS) 



Transverse section through the pons and cerebellum at the level of the principal motor nucleus of the 

trigeminal nerve. New-born babe. (Weigert-Pal, series ii. section No. 212.) 

Br.conj., brachium conjunctivum ; C.t., corpus trapezoideum ; F.l.m., fasciculus longitudinalis 
medialis ; F.Py., fasciculi pyramidales in the pars basilaris pontis ; L.m., lemniscus medialis ; X. V. (dec. ) , 
decussating part of root of N. trigeminus ; N. V. (motor), root of N. trigeminus ; N. V.(scrts), sensory root 
of N. trigeminus; N. V.I., root fibres of N. abducens ; Nu.m.m.n. V., nuclei motorii minores N. trigemini ; 
Nu.m.p.n. V., nucleus motorius princeps N. trigemini; Nu.o.s., nucleus olivaris superior and superior 
olivary complex ; R.d.n. V., radix descendens [mesencephalica] N. trigemini ; S.g., substantia gelatinosa. 
(From Barker, The Nerv. Syst., New York, 1899, p. 483, Fig. 313.) 



(16) Medial longitudinal fasciculus (fasciculus longitudinalis medialis) 

(0. T. posterior longitudinal bundle). 

(17) Interolivary layer of lemniscus (stratum interolivare lemnisci). 

(18) Decussation of lemniscus or fillet (decussatio lemniscorum) (0. T. 

sensory decussation of medulla oblongata). 



DISSECTION OF THE HEAD AND NECK 



353 



(19) Restiform body (corpus resti forme) (0. T. inferior cerebellar 

peduncle), 
(a) Fasciculi of restifonn body (fasciculi corporis restiformis). 

(20) Cerebello-olivary fibres (fibrae cerebelloolivares) . 

(21) Pyramidal fasciculi (fasciculi pyramidales) . 

(22) External arcuate fibres (fibrae arcuatae externae). 

Sections of Pons (Sectiones pontis). 

Make four sections through the pons. (See Spalteholz. Fig. 
723.) 

FIG. 166. 




Transverse section through isthmus rhombencephali of new-born babe. (Weigert-Pal, series ii. 

section No. 268.) 

Sr.conj., brachium conjunctivum ; C.i., colliculus inferior; y, nucleus described by Westphal as 
probably concerned in the origin of the N. trochlearis ; F.l.m., fasciculus longitudinalis medialis ; F.Py., 
fasciculi longitudinales [pyramidales] ; L.I., lemniscus lateralis; L.m., lemniscus medialis; N.IV., 
decussatio nervorum trochlearium ; N.V., N. trigeminus ; yu.l.l., nucleus lemnisci lateralis; Nu.r.t. 
nucleus reticularis tegmenti pontis ; R.d. V., radix descendens [meseucephalica] nervi trigemini. (From 
Barker, The Nerv. Syst., New York, 1899, p. 484, Fig. 314.) 

(1) About at the junction of the pons and the medulla, passing through 

the level of entrance of N. acusticus. 

(2) At the level of the roots of N. facialis and N. abducens. 

(3) At the level of the roots of N. trigeminus. 

(4) Through the velum medullare anterius and the middle of the pons. 

Examine first the unstained cross-sections and subsequently 
sections, from the same levels, stained by Weigert's method. 

23 



354 LABORATORY MANUAL OF HUMAN ANATOMY 

Use a hand-lens or dissecting microscope. Make drawings indi- 
cating 

In dorsal part of pons (pars dorsalis pontis). 

(1) Median raphe (raphe). 

(2) Nucleus of N. abducens (nucleus N. abducentis) (0. T. nucleus of 

sixth nerve). 

(3) Motor nuclei of trigeminal nerve (nuclei motorii N. trigemini}. 

(4) Descending or mesencephalic root of trigeminal nerve (radix 

mesencephalica N. trigemini). 

(5) Spinal tract of trigeminal nerve (tractus spinalis N, trigemini). 

(a) Nucleus of spinal tract of trigeminal nerve (nucleus tractus 
spinalis N. trigemini). 

(6) Nucleus of facial nerve (nucleus N'. facialis). 

(7) Root of facial nerve (radix N. facialis). 

(a) First part (pars prima). 

(b) [Internal] knee (genu [internum]). 

(c) Second part (pars secunda). 

(8) Nuclei of acoustic nerve (nuclei N. acustici) (0. T. auditory 

nucleus). 

(a) Nuclei of cochlear nerve (nuclei N. cochlearis). 

(aa) Ventral (nucleus N. cochlearis ventralis). 

(ab) Dorsal (nucleus N. cochlearis dorsalis [tubercu- 

lum acusticum] ) . 

(b) Nuclei of vestibular nerve (nuclei N. vestibularis) . 

(ba) Medial nucleus (nucleus N. vestibularis medialis). 

(bb) Lateral nucleus (nucleus N. vestibularis lateralis 

[Deitersi] ) . 
(be) Superior nucleus (nucleus N. vestibularis superior 

[Bechterewi] ) . 
(bd) Nucleus of descending root (nucleus N. vestibularis 

radicis descendentis) . 

(9) Superior olivary nucleus (nucleus olivaris superior). 

(10) Nucleus of lateral lemniscus (nucleus lemnisci lateralis). 

(11) Medial longitudinal fasciculus (fasciculus longitudinalis medialis) 

(0. T. posterior longitudinal bundle). 

(12) Reticular formation (formatio reticularis) . 

(13) Trapezoid body (corpus trapezoideum) . 

(14) Fillet or lemniscus (lemniscus). 

(a) Medial (sensory) fillet (lemniscus medialis [sensitivus] ) . 

(b) Lateral (acoustic) fillet (lemniscus lateralis [acusticus]) . 

In basilar part of pons (pars basilaris pontis). 

(1) Deep fibres of pons (fibrae profundae pontis). 

(2) Longitudinal pyramidal fasciculi (fasciculi longitudinales [pyrami- 

dales]). 

(3) Nuclei of pons (nuclei pontis). 

(4) Superficial fibres of pons (fibrae pontis superficiales) . 

Sections of Cerebellum (Sectiones cerebelli). 

Make a sagittal median section through the vermis. (Vide 
Fig. 144.) 



DISSECTION OF THE HEAD AND NECK 



355 



Study- 



(1) Medullary body (corpus medullare). 

(2) Medullary laminae (laminae medullares). 

(3) Arbor vitae (arbor vitae) ("tree of life"). 

(4) Cortical substance (substantia corticalis). 

(a) Inner, yellowish or reddish-brown, " granular" layer (stratum 

granulosum). 

(b) Outer gray layer (stratum cinereum). 

(c) Layer of Purkinje's cells between (a) and (b) (stratum gan- 

gliosum ) . 




Transverse section through brain of new-born babe. Level of colliculi inferiores of corpora 

quadrigemina. ( Weigert-Pal, series ii. section No. 290. ) 

Aq.cer., aquaeductus cerebri ; a, fibres running from lateral lemniscus toward dorsal border of 
brachium conjunctivum ; Br.Conj., brachium conjunctivum; C.c.L, commissure between the colliculi 
inferiores; Dec.Bech., ventral portion of brachium conjunctivum, which in reality forms a commissure 
between the superior nuclei of the vestibular nerves of the two sides; F.l.m., fasciculus longitudinalis 
medialis ; F.Py., fasciculi longitudinales pontis (pyramidales) ; L.I., lemniscus lateralis in large part 
terminating in the nucleus of the colliculus inferior ; L.m., lemniscus medialis; N.IV., N. trochlearis ; 
Nu.Coll.inf., nucleus colliculi inferioris ; Fu.c.s.(l), nucleus centralis superior, pars lateralis ; Nu.c.8.(m), 
nucleus centralis superior, pars medialis; R.d.n.V., radix descendens [mesencephalica] N. trigemini; 
St.gr.c., stratum griseum centrale. (From Barker, The Nerv. Syst., New York, 1899, p. 485, Fig. 315.) 

Make a frontal section through the left half of the cerebellum 
at about its middle (cf. Spalteholz, Fig. 743), and a horizontal 
section through the right half of the cerebellum in the general 



356 LABORATORY MANUAL OF HUMAN ANATOMY 

direction of the brachium conjunctivum (cf. Spalteholz, Fig. 
744). In these, study the following: 

(1) Dentate nucleus (nucleus dentatus). 

(a) Hilus of dentate nucleus (hilus nuclei dentati). 

(b) Capsule of nucleus dentatus (capsula nuclei dentati). 

(2) Nucleus of fastigium ("roof") (nucleus fastigii). 

(3) Nucleus fclobosus (nucleus globosus) (" spherical nucleus"). 

(4) Emboliform nucleus (nucleus emboliformis) (0. T. cork or plug). 

FIG. 168. 




Dpc.Br.Conj. 



Transverse section through mesencephalon of new-born babe. Level of colliculi superiores of 
corpora quadrigemina. (Weigert-Pal, series ii. section No. 338.) 

Aq.cer., aquaeductus cerebri ; Dec.Br.Conj., decussatio brachii conjunctivi ; D.t., decussatio tegmenti 
ventralis (ventrale Haubcnkreuzung of Forel) ; F.l.m,, fasciculus longitudinalis medialis ; F.Py., fasciculi 
pyramidales in the pars basilaris pontis; L.m., lemniscus medialis; N.IV., N. trochlearis; Nu.l.s., 
nucleus lateralis superior of Flechsig; Nu.n.IV., nucleus N. trochlearis; St.alb.p., stratum album pro- 
fundum; St.gr.c., stratum griseum centrale ; S.n., substantia nigra. (From Barker, The Nerv. Syst., 
New York, 1899, p. 486, Fig. 316.) 

Sections of Rhombencephalic Isthmus, Corpora Quadrigemina, and 
Cerebral Peduncle (Sectiones isthmi, corporum quadrigemi- 
norum, et pedunculi cerebri). 

Make two sections: (1) through the inferior colliculus at the 
level of the nucleus of the N. trochlearis; (2) through the level 
of the roots of the N. oculomotorius, nucleus ruber, superior 
colliculus, and lateral geniculate body. (Cf. Spalteholz, Fig. 
723.) 



DISSECTION OF THE HEAD AND NECK 



357 



Study- 

In the isthmus rhombencephali. 

(1) Interpeduncular ganglion (ganglion inter peduncular e). 

(2) Nucleus of trochlear nerve (nucleus N. trochlearis). 
In the pedunculus cerebri. 

(A) Tegmentum. 

(1) Central gray layer (stratum griseum centrale). 

(2) Reticular formation (formatio reticularis) . 

(3) Medial longitudinal fasciculus (fasciculus longitudinalis 

medialis) (0. T. posterior longitudinal bundle). 



FIG. 169. 



Coll.sup. 



Aq.cer, 
St.gr.c, 




a 



Transverse section through mesencephalon, colliculi superiores of corpora quadrigemina and cerebral 

peduncle of new-born babe. (Weigert-Pal, series ii. section No. 384.) 

Aq.cer., aquaeductus cerebri; Coll.sup., colliculus superior; D.t., decussatio tegmenti dorsalis (fon- 
taineartige Haubenkrcuzung of Meynert); F.l.m., fasciculus longitudinalis medialis; F.Py., fasciculi 
pyramidales in the basis pedunculi ; F.r.(M), fasciculus retroflexus Meynerti ; L.m., lemniscus medialis ; 
Nu. F.l.m., nucleus fasciculi longitudinalis medialis or nucleus commissurae posterioris (oberer Octdomo- 
toriuskern of Darkschewitsch) ; Nu.n.III, nucleus N. oculomotorii ; Nu.r., nucleus ruber ; N.III, N. 
oculomotorius ; St.alb.p., stratum album profundum; St.gr.c., stratum griseum centrale ; S.n., substantia 
nigra ; a, region of Flechsig's Fussscfdeife ; /3, temporo-occipital tract to pons ; y, frontal tract from 
pallium to pons. (From Barker, The Nerv. Syst, New York, 1899, p. 487, Fig. 317.) 



(4) Descending root of trigeminal nerve (radix descendens N. 

trigemini). 

(5) Nucleus of descending root of trigeminal nerve (nucleus 

radicis descendentis N. trigemini = nuclei motorii mi- 
nor es N. trigemini}. 

(6) Nucleus of oculomotor nerve (nucleus N. oculomo.torii) 

(0. T. nucleus of III. nerve). 

(7) Nuclei of tegmentum (nuclei tegmenti). 

(a) Red nucleus (nucleus ruber). 

(8) Decussations of tegmenta (decussationes tegmentorum) . 



358 LABORATORY MANUAL OF HUMAN ANATOMY 

(a) Decussation of brachium conjunctivum (decussatio 

brachii conjunctivi). 

(b) Dorsal decussation of tegmentum (decussatio teg- 

menti dorsalis) (German 0. T. fontaineartige 
Haubenkreuzung) . 

(c) Ventral decussation of tegmentum (decussatio teg- 

menti ventralis). 

(9) Lateral fillet (lemniscus later alls}. 
(10) Medial fillet (lemniscus medialis). 

(B) Base of peduncle (basis pedunculi) (0. T. "foot" of cerebral 
peduncle, or pes pedunculi). 

(1) Pyramidal path (fasciculi cerebrospinales) . 

(2) Temporal pontile path (fasciculus temporopontilis) (0. T. 

Turk's bundle). 

(3) Frontal pontile path (fasciculus frontopontilis) (0. T. Ar- 

nold's bundle). 

Between (A) and (B), study the substantia nigra (substantia 
nigra) (" black substance"). 

In the corpora quadrigemina. 

(1) Zonal layer (stratum zonale). 

(2) Gray layer of superior colliculus (stratum griseum colliculi supe- 

rioris). 

(3) Nucleus of inferior colliculus (nucleus colliculi inferioris). 

(4) Deep white layer (stratum album profundum). 



Sections through Prosencephalon (Sectiones diencephali et telen- 
cephali). 

Take the portion still remaining of the right cerebral hemi- 
sphere; with a broad, thin, sharp brain-knife, make horizontal 
slices, one-half or one centimetre thick, down as far as the level 
of the commissura anterior cerebri. Make a drawing of the 
surface of each slice. (Vide Fig. 177.) 

The left half of the brain, thus far preserved intact, should 
now be divided, at the choice of the instructor, either into vertical 
frontal or into obliquely frontal sections, the latter according to 
the method of Pitres. 1 All the oblique sections pass in planes 
parallel to the course of the sulcus centralis Rolandi. Place 
the four fingers of the left hand in the sulcus centralis [Eolandi] , 
the hemisphere lying upon its medial surface with the polus 
occipitalis directed towards you. With the sharp, broad, thin 
brain-knife, make six sections from before backward, as indi- 
cated in the accompanying diagram. (Cf. Fig. 170.) 



1 Pitres, Recherches sur les lesions du centre oval des hemispheres cerebraux, 
etudiees au point de vue des localisations cerebrales. Paris, 1877. 



DISSECTION OF THE HEAD AND NECK 



359 



(1) Prefrontal section, passing through the front of the lobus frontalis 

about live centimetres in front of the sulcus centralis and parallel 
to it. 

(2) Operculo frontal or pediculo frontal section, through the pars opercu- 

laris of the gyms frontalis inferior and the corresponding portions 
of the gyrus frontalis medius and gyrus frontalis superior ; in other 
words, through the " feet" of the frontal gyri. 

(3) Frontal section, through the middle of the gyrus centralis anterior. 

(4) First parietal section, through the middle of the gyrus centralis pos- 

terior. 

(5) Second parietal or pediculoparietal section, through the anterior ex- 

tremities ("feet") of the lobulus parietalis superior and lobulus 
parietalis inferior. 

(6) Occipital section, about one centimetre in front of the fissura parieto- 

occipitalis. 



FIG. 170. 
Operculofrontal 



Prefrontal section 



Frontal pj^ parietal 



Second parietal 




Occipital 



Prefrontal 

Operculofrontal 

Frontal / 

First parietal / 

Second parietal 

Pitres' method of sectioning the cerebral hemisphere. 1 

It will be advantageous to the student while studying anat- 
omy to become familiar with these obliquely frontal sections, as 
well as with the vertical frontal, for it is the former that are 
more often employed at the autopsy table of the pathological 
laboratories. 

The prefrontal section shows the cortex and white matter of the three 
frontal gyri, the orbital gyri, and the medial surface of the frontal lobe. 

The pediculo frontal section passes through the three frontal gyri, anterior 
end of island, orbital gyrus, corpus callosum, eaput nuclei caudati, ante- 
rior part of nucleus lentiformis, and lentieulostriate part of capsula 
interna. 



1 The lines indicating the planes of the sections slope too much in this figure. 



360 LABORATORY MANUAL OF HUMAN ANATOMY 

The frontal section passes through the gyrus centralis anterior, island, 
temporal gyri, corpus callosurn, cauda nuclei caudati, thalamus, middle 
piece of nucleus lentiformis, anterior part of lenticulo-optic part of 
capsula interna, capsula externa, and claustrum. 

The first parietal section passes through the gyrus centralis posterior, 
island, temporal gyri, corpus callosum, cauda nuclei caudati, posterior 
end of thalamus and of nucleus lentiformis, posterior end of lenticulo- 
optic part of capsula interna, capsula interna, capsula externa, and 
claustrum. 

The pediculo parietal section passes through the lobuli parietalis superior 
et inferior, temporal gyri, corpus callosum, most posterior part of 
thalamus, and cauda nuclei caudati. 

The occipital section passes through the cortex and white matter of the 
lobus occipitalis. 

In addition to the horizontal sections and frontal sections 
above mentioned, the student should study, if possible (perhaps 
from the anatomical museum), two other sections: 

(1) Section through the brain in a plane passing parallel to the course 

of the brachia conjunctiva and through them. (Cf. Spalteholz, 
Fig. 744.) 

(2) Section through the brain in a plane parallel to the course of the 

cerebral peduncles and through them. (Cf. Spalteholz, Fig. 745.) 

FIG. 171. 

Taenia semicircularis^ 
Nucleus lateralis thalami. 
Lamina medullaris medialis^ 

Nucleus medialis thalami. 

Ventriculus tertius- .. 

-Lamina medullaris lateralis 



Forel's Feld H 
Nucleus ruber 




/*V ' '" ' J tfF$&%&*3xr N > 

; ? ; ^>^^^PN ^Nucleus hypothalamicus (corpus Luysi) 



,"***^3SX 

\ x BAThof Forel 
N. oculomotorius Substantia nigra 

Frontal section through the human brain-stem. 

BA Th, large bundle of fibres which, coming from the nucleus ruber and its capsule, runs upward, 
lateralward, and dorsalward to the ventral part of the thalamus to the reticular layer, to the lamina 
medullaris lateralis, etc., where the fibres become so interwoven with others that they cannot be fol- 
lowed farther; Ford's Feld H, dorsal white matter of regio subthalamica. (After A. Forel, Arch. f. 
Psychiat., Berl., Bd. vii., 1877, Taf. vii., Fig. 10.) 

Drawings should be made of all these sections, and the fol- 
lowing structures designated when met : 

Sections of Hypothalamus (Sectiones hypothalami). 

(1) Hypothalamic nucleus, or Luys's body (nucleus hypothalamicus [cor- 

pus Luysi}} (0. T. subthalamic nucleus). 

(2) Gray part of hypothalamus (pars grisea hypothalami). 



DISSECTION OF THE HEAD AND NECK 



361 



(3) Superior commissure of Meaner! (commissura superior [Meynerti]). 

(4) Inferior commissure of v. Gudden (commissura inferior [Guddeni]). 

(5) Nuclei of mammillary body (nuclei corporis mammillaris) . 



FIG. 172. 
Lamina medullaris media 



Capsula interna___^;c 



Nucleus lentifonnis. 



Lamina medullaris medialis 

/ Nucleus medialis thalami (6) 

/ / (centre median) 

Nucleus medialis thalami (a) 

Taenia thalami 
'~ 1- Lamina medullaris thalami 



Nucleus ruber 



'!--- Fasciculus retroflexus 
[M^nerti] 

Fasciculus pedunculomammillaris 
pars tegmentalis 



Nucleus hypothalamicus (corpus Luysi) 
Ventriculus lateralis (cornu inferius) / ,' 

Nucleus ventralis thalami (a) ' / 
Nucleus ventralis thalami (6) ! 

Basis pedunculi 

Frontal section through a normal human brain at the level of the lower end of the nucleus 

hypothalamicus. 

a, dorsal white matter of nucleus ruber ; /3, ventral white matter of nucleus ruber ; y, lateral white 
matter of nucleus ruber. (After C. von Monakow, Arch. f. Psychiat., Berl., Bd. xxvii., 1895, Taf. iii., 
Fig. 20.) 

(6) Thalamomammillary fasciculus (fasciculus thalamomammillaris 
[Vicq d'Azyri]) (0. T. bundle of Vicq d'Azyr). 




FIG. 173. 



Capsula interna _, 



Nucleus ventralis thalami (ant.) - 



Putamen \ / 

Globus pallidus, pars lateralis 
Globus pallidus, pars medialis' 

Commissura anterior cerebri 




Nucleus lateralis thalami 

/ Nucleus anterior thalami (a) 

/ Capsula ventralis nucl. ant. thalami 
B5 ' ' -Hi X / Taenia thalami 

. Fasciculus thalamo-mammillaris 

[Vicq d'Azyri] 

"T Stratum griseum centrale 
*--j Pedunculus thalami medialis 
y: ,/! ?', \ x -Columna fornicis 
V' 

-'-.'/ * 



\Ansa lenticularis, pars ventralis 



Frontal section through a normal human brain at level of anterior part of thalamus. (After C. von 
Monakow, Arch. f. Psychiat., Berl., Bd. xxvii., 1895, Taf. iv., Fig. 33.) 



(7) Pedunculomamnrillary fasciculi (fasciculi pedunculomammillares) . 

(a) Tegmental part (pars tegmentalis). 

(b) Basilar part (pars basilaris). 



362 



LABORATORY MANUAL OF HUMAN ANATOMY 



(8) Peduncular loop (ansa peduncularis) . 

(a) Lenticular loop (ansa lenticularis) . 

(b) Inferior peduncle of thalamus (pedunculus thalami inferior) 

Sections of Thalamencephalon (Sectiones thalamencephali). 

(1) Zonal layer (stratum zonale). 

(2) Anterior nucleus of thalamus (nucleus anterior thalami). 

(3) Medial nucleus of thalamus (nucleus medialis thalami). 

(4) Lateral nucleus of thalamus (nucleus lateralis thalami). 



FIG. 174. 



Radiatio corporis 

callosi 

Bulbus cornu 
posterioris 



Calcar avis 



Hippo- 
campus 

Corpora 
quadrige- 

mina 

Nucleus 

colliculi J!/f /, 
inferioris 




Splenium corporis 
i .-' callosi 

Telachorio- 
idea ven- 
triculi 
tertii 
Corpus 
.pineale 
Cornu pos- 
terius ven- 
triculi 
lateralis 
Glomus 
chorio- 
ideum 



Aquaeduc- %'#f 
tus cerebri ;>- 

M^!l:~x:; 

Nucleus N.. -$&_,',_ % J\ 
trochlearis 
Fasciculus 
longitudi- ""^ s 
nal is medialis '< 

Cerebellum 
Brachium pontis-- 

Flocculus-"" 
Pyramis medullae oblongatae--' 



Radiatio 
"~' occipito- 
thalamica 
s __- Eminentia 
jJ collateralis 

x ___Fissura 
collateralis 

Lemniscus 
lateralis 

Brachium con- 
junctivum 



stratum gri- 
seum centrale 
Lemniscus 
medialis 



"^ ^ G Upper ends f the Py^^ds of the medulla oblongata, through the splenium 
Wi?n 190 C 3 3Aufl n ^ ? P Steri r parts of the lateral ventricles. (After Toldt, Anat. Atlas, 

(5) Medullary layers of thalamus (laminae medullares thalami). 

(6) Nucleus of medial geniculate body (nucleus corporis geniculati me- 

dialis). 

(7) Nucleus of lateral geniculate body (nucleus corporis qeniculati lat- 

eralis). 

(8) Nucleus of habenula (nucleus habenulae). 

Retroflex fasciculus (fasciculus retroflexus [Meynerti]). 

Sections of Telencephalon (Sectiones telencephali). 

(1) Cortical substance (substantia corticalis). 

Observe the difference in macroscopic appearance in different 
areas in the cortex. 

(2) Semioval centre (centrum semiovale). 



DISSECTION OF THE HEAD AND NECK 



363 



FIG. 175. 



Ventriculus lateral! 

(pars centralist 
Plexus chorioid- x 
eus ventriculi 
lateralis 
Nucleus 
caudatus 
Massa inter- 
media 



Nucleus ( Putamen - 
Globus 
pallidus 



lenti- 
formis 



Capsul 
externa 
Claustrum fe 
Ansa peclun-'';.' 
cularis ^ 

Tractus options, -.- 

Pedunculus f, 

thalami ''" 

inferior . 

Cornu inf erius s' v 

ventriculi 

lateralis >* 

Digitatione.s 

hippocampi 

N. oculomotoriu 




Corpus 
callosum 

Fornix 



./*Ventriculus 
tertius 

Thalamus 
Fasciculus 
^ thalamo- 
mammillaris 
Tegmental 
^.bundle to the 
lenticular 
nucleus 
- Nucleus 
hypothalam- 
icus (Corpus 
Luysi) 

Substantia 

nigra 



pedunculi 

Corpus 
-mammillare 

Fossa 

interpedun- 
cularis 



Pons (Varioli) 

Section through the third ventricle, cerebral peduncles, and corpora mammillaria. (After Toldt, Anat. 
Atlas, Wien, 1903, 3 Aufl., p. 792, Fig. 1219.) 



FIG. 176. 



Nucleus caudatus 
(caput) 



Capsula 

interim (pai 

frontalis) 



{Puta- f 
men . XJS 1. 
Globus 
pal- ! 
lidus 

Lamina 
medullaris-- 

Capsula 
externa 



Claustrum -J 




Fissura longitudinalis 
cerebri 

Corpus callosum 



Cornu anterius 
ventriculi 
lateralis 
lexus chorioi- 
deus ventriculi 

lateralis 
Septum 
pellucidum 



TVna 



Foramen inter- 

vetitriculare 

i Monroi) 



Substantia per- 

forata anterior 

Uncus Commissura anterior (cerebri) 

Section through the optic chiasma and anterior cerebral commissure. 

1903, 3 Aufl., p. 793, Fig. 1221.) 



fornicis 



_. Fissura cerebri 
| lateralis [Sylvii] 

jf-^Gyri insulae 

Recessus opti- 
cus ventnculi 
tertii 

ractus opticus 

Chiasma opti- 
cum (most pos- 
terior part) 

'"* Commissura inferior 

(Guddeni i 
(After Toldt, Anat. Atlas, Wein, 



364 LABORATORY MANUAL OF HUMAN ANATOMY 

(3) Decursus ("running down") of cerebral fibres (decursus fibrarum 

cerebralium) . 

(4) Arcuate fibres of cerebrum (fibrae arcuatae cerebri). 

(a) Cingulum (cingulum) ("girdle"). 

(b) Superior longitudinal fasciculus (fasciculus longitudinalis 

superior). 

(c) Inferior longitudinal fasciculus (fasciculus longitudinalis in- 

ferior). 

(d) Uncinate ("hooked") fasciculus (fasciculus uncinatus). 

(e) Radiation of corpus callosum (radiatio corporis callosi). 

(ea) Frontal part (pars frontalis) (0. T. forceps minor). 

(eb) Parietal part (pars parietalis). 

(ec) Temporal part (pars temporalis) . 

(ed) Occipital part (pars occipitalis) (0. T. forceps 

major). 
(/) Tapetum (tapetum) (" carpet" or " tapestry"). 

(5) Lentiform nucleus (nucleus lentiformis) (0. T. lenticular nucleus). 

(a) Putamen (putamen) (" shell" or " paring"). 

(b) Globus pallidus (globus pallidus) (" pale sphere"). 

(6) Claustrum (claustrum) ("bulwark" or "barrier"). 

(7) External capsule (capsula externa). 

(8) Internal capsule (capsula interna). 

(a) Knee of internal capsule (genu capsulae internae). 

(b) Frontal part of internal capsule (pars frontalis capsulae in- 

ternae) (0. T. anterior limb). 

(c) Occipital part of internal capsule (pars occipitalis capsulae 

internae) (0. T. posterior limb). 

(9) Amygdaloid nucleus (nucleus amygdalae) ("almond" nucleus). 

(10) Corona radiata. 

(a) Frontal part (pars frontalis). 

(b) Parietal part (pars parietalis). 

(c) Temporal part (pars temporalis). 

(d) Occipital part (pars occipitalis). 

(11) Radiation of corpus striatum (radiatio corporis striati). 

(12) Oecipitothalamic radiation (radiatio occipitothalamica [Gratioleti]) 

(0. T. optic radiation). 

(13) Anterior commissure of cerebrum (commissura anterior cerebri). 

(a) Anterior part (pars anterior). 

(b) Posterior part (pars posterior). 



CONDUCTION PATHS OF THE NEKVOUS SYSTEM. 

The student should now take up systematically the study of 
the various motor, sensory, and associative conduction paths of 
the nervous system. For frequent consultation, Section VI. of 
' The Nervous System and its Constituent Neurones" (D. Ap- 
pleton and Co., New York) is recommended. A study of sections 
of various spinal cords in which secondary degenerations have 



DISSECTION OF THE HEAD AND NECK 365 

taken place is desirable for a thorough understanding of the 
complex relations which exist. 

Descending Fibre Systems in Spinal Cord. 

(1) Pyramidal tracts (anterior and lateral), from cortex of central gyri 

of same and opposite side. 

(2) Anterior marginal bundle from nucleus fastigii. 

(3) Sulcomarginal fasciculus = path from superior colliculus of corpora 

quadrigemina. 

(4) Descending paths in fasciculus lateralis proprius. 

(a) Tract from Deiters's nucleus to lateral funiculus. 
(6) Tract from red nucleus of opposite side to lateral funiculus. 
(c) Tract from nuclei laterales superior, medius, inferior, to lateral 
funiculus. 

(5) Descending paths in posterior funiculus. 

(a) Descending limbs of bifurcation of posterior root-fibres. 

(b) Endogenous fibres of posterior funiculi (comma bundle, ven- 

tral area, oval centre, median triangle). 

(6) Other descending paths in lateral and anterior funiculi. 

(a) Endogenous fibres (tautomeric and heteromeric). 

Ascending Fibre Systems in Spinal Cord. (Vide Fig. 103.) 

(1) Direct continuation of ascending limbs of bifurcation of posterior 

root-fibres to nucleus funiculi gracilis, nucleus funiculi cuneati, 

and partly to cerebellum. 
Secondary path: from nuclei of dorsal funiculi, through decussa- 

tio lemniscorum to stratum interolivare lemnisci of opposite side, 

and then through lemniscus median's to [ventro-] lateral nucleus 

of thalamus. 
Tertiary path : from ventrolateral nucleus of thalamus to cortex of 

central gyri (somaesthetic area). 

(2) Fibre systems leading from the end-stations of posterior root-fibres 

in the spinal cord to higher centres, 
(a) Cerebellospinal fasciculus (fasciculus cerebellospinalis) (0. T. 

direct cerebellar tract), from nucleus dorsalis of Clarke to 

cerebellum. 
(6) Gowers's tract (fasciculus anterolateralis superficialis [Gow- 

ersi]), from base of anterior horn to cerebellum. 

(c) From posterior horn upward in lateral limiting layer of gray 

matter, and in opposite anterior funiculus. 

(3) Fibre systems from some of cells in anterior horns upward in fascicu- 

lus anterior proprius and fasciculus lateralis proprius to formatio 
reticularis. 

Fibre Systems of Cerebral Nerves. 

Like the motor spinal nerves, the motor cerebral nerves arise 
from nuclei of origin (nuclei originis) in the brain-stem, the 
fibres leaving the central system to terminate in the muscles. 



366 LABORATORY MANUAL OF HUMAN ANATOMY 

Like the sensory spinal nerves, the sensory cerebral nerves arise 
from ganglia outside the central nervous system and their axones 
terminate in certain end-nuclei (nuclei terminates) inside the 
central system; in these end-nuclei are cells which give off the 
axones of secondary fibre systems. 



OLFACTORY NERVES (NN. OLFACTORII). 

Nuclei originis: bipolar cells of regio olfactoria of nasal mucous mem- 
brane. 

Nuclei terminates : in olfactory glomeruli of bulbus olf actorius. 
Secondary path: from mitral cells of bulbus olf actorius through tractus 
olfactorius to 

(a) Gray matter of trigonum olfactorium. 

(b) Through stria olfactoria lateralis to uncus and thence to hippo- 

campus and gyrus cinguli. 

(c) Through stria olfactoria intermedia to substantia perforata ante- 

rior. 

(d) Through stria olfactoria medialis to gyrus subcallosus. 

BIPOLAR CELLS OF RETINA (analogous, for visual path, to sensory fibres of pos- 
terior roots of spinal nerves). 
Nuclei terminates: ganglion cell layer of retina, 

Secondary path: from ganglion cell layer of retina, through (badly 
named) N. OPTICUS, chiasma opticum, and tractus optici, to 

(a) Corpus geniculatum laterale. 

(b) Pulvinar thalami. 

(c) Superficial and middle gray strata of superior colliculus of corpora 

quadrigemina. 
Tertiary paths: 

(a) From corpus geniculatum laterale and pulvinar thalami, through 

radiato occipitothalamica [Gratioleti], to cortex of occipital lobe 
about the fissura calcarina. 

(b) From middle gray layer of colliculus superior, through decussatio 

tegmenti dorsalis of Meynert and fasciculus longitudinalis me- 
dialis of opposite side, to eye-muscle nuclei and spinal cord ; this 
is the so-called "optic-acoustic reflex path" (Held), 

OCULOMOTOR NERVE (N. OCULOMOTORIUS). 

Nuclei originis: nucleus of oculomotor nerve (nucleus N. oculomotorii) 

in tegmentum of cerebral peduncle. 
Cortical control: 

(a) From cortex of central gyri through capsula interna (?). 

(b) From cortex about fissura calcarina to superior colliculus and then 

through optic-acoustic reflex path. 

TROCHLEAR NERVE (N. TROCHLEARIS). 

Nucleus originis: nucleus of trochlear nerve (nucleus N. trochlearis) in 

isthmus rhombencephali on opposite side, through decussatio nervorum 

trochlearium. 
Cortical control: probably same as for N. oculomotorius. 



DISSECTION OF THE HEAD AND NECK 367 

TRIGEMINAL NERVE (N. TRIGEMINUS). 

(A) Motor part (portio minor). 

Nuclei originis : 

(a) Principal motor nucleus (nucleus motorius princeps N. trigemini) 

in pars dorsalis pontis. 

(b) Lesser motor nuclei (nuclei motorii minores N. trigemini). 

(ba) Cells of locus caeruleus. 

(bb) Cells along descending or mesencephalic root (nucleus 

radicis descendentis ) . 

Cortical control: from lower third of gyrus centralis anterior and feet 
of frontal gyri, through capsula interna and partly through basis 
pedunculi (pyramidal tract), partly through area of lemniscus me- 
dialis (accessory lemniscus of v. Bechterew). 

(B) Sensory part (portio major). 

Nucleus originis: semilunar ganglion (ganglion semilunare [Gasseri]). 
Nuclei terminales: 

(a) Main sensory nucleus (nucleus sensibilis N. trigemini). 

(b) Nucleus of spinal tract (nucleus tractus spinalis N. trigemini). 
Secondary paths : 

(a) To opposite medial lemniscus and through it to [ventro-] lateral 

nucleus of thalamus. 

(b) To substantia reticularis alba of same and of opposite side, and 

through it to [ventro-] lateral nucleus of thalamus. 

Tertiary path: from [ventro-] lateral nucleus of thalamus to central 
gyri (somaesthetic area). 

ABDUCENT NERVE (N. ABDUCENS). 

Nucleus originis: nucleus of abducent nerve (nucleus N. abducentis) in 

pars dorsalis pontis. 
Cortical control: 

(a) Pyramidal tract (*?). 

(b) " Accessory lemniscus" (?). 

(c) Indirectly through optic-acoustic reflex path. 

FACIAL NERVE (N. FACIALIS). 

Nucleus originis: nucleus of facial nerve (nucleus N. facialis) in ventral 

lateral part of pars dorsalis pontis close to medulla oblongata. 
Cortical control: 

(a) Through pyramidal tract of the same and of the opposite side. 

(b) Through the "accessory descending lemniscus" of the same and of 

the opposite side (Hoche). 

INTERMEDIATE NERVE (N. INTERMEDIUS). 

Nucleus originis: geniculate ganglion (ganglion geniculi). 

Nucleus terminalis: probably the same as for N. vagus and N. glosso- 

pharyngeus. 
Secondary path: uncertain. 

ACOUSTIC NERVE (N. ACUSTICUS). 

(A) Vestibular nerve (N. vestibularis) . 

Nucleus originis: vestibular ganglion (ganglion vestibulare) . 
Nuclei terminales : 

(a) Lateral nucleus (nucleus N. vestibularis lateralis [Deitersi]). 



368 LABORATORY MANUAL OF HUMAN ANATOMY 

(b) Medial nucleus (nucleus N. vestibularis medialis). 

(c) Superior nucleus (nucleus N. vestibularis superior). 

(d) Nucleus of descending root (nucleus radicis descendentis) . 
Secondary paths : 

(a) From lateral nucleus of Deiters to lateral funiculus of cord. 

(b) From medial and superior nuclei to fasciculi longitudinales me- 

diales of 'two sides for eye-muscle nuclei, etc. 

(c) From lateral and superior nuclei to nucleus fastigii, nucleus den- 

tatus, and cortex vermis. 

(d) From all the terminal nuclei, through the substantia reticularis 

alba to the [ventro-] lateral nuclei of the thalamus (?). 
Tertiary path: from [ventro-] lateral nuclei of thalamus to central gyri 

(somaesthetic area). 
(B) Cochlear nerve (N. cochlearis). 

Nucleus originis : spiral ganglion (ganglion spirals). 
Nuclei terminates : 

(a) Ventral nucleus (nucleus N. cochlearis ventralis). 

(b) Dorsal nucleus (nucleus N. cochlearis dorsalis [nucleus tuberculi 

acustici] ) . 
Secondary paths: 

(a) Fibres from ventral nucleus through corpus trapezoideum to 

upper olives, and through lateral lemniscus to nucleus of lat- 
eral lemniscus, inferior colliculus, middle gray layer of supe- 
rior colliculus, and through brachium quadrigeminum inferius 
to medial geniculate body, possibly some even to temporal 
cortex. 

(b) Fibres from dorsal nucleus through stria medullares to trapezoid 

body. 

Tertiary paths: from end-stations of secondary path (a), especially 
from nucleus colliculi inferioris and nucleus corporis geniculati me- 
dialis, through capsula interna and pars temporalis of corona radiata, 
to gyrus temporalis superior (junction of third and fourth fifths) 
and adjacent gyri temporales transversi. [When this cortical area is 
diseased, the patient has " word-deafness."] 

GLOSSOPHARYNGEAL AND VAGAL NERVES (N. GLOSSOPHARYNGEUS ET N. VAGUS). 

(A) Motor part. 

Nuclei originis: 

(a) Dorsal nucleus (nucleus dorsalis Nn. glossopharyngei et vagi) in 

medulla oblongata just medial from ala cinerea. 

(b) Ventral nucleus (nucleus ambiguus) in the formatio reticularis 

of medulla oblongata just dorsal from nucleus olivaris accesso- 
rius dorsalis. 
Cortical control: 

(a) Pyramidal tract from central gyri. 

(b) Accessory lemniscus (?). 

(B) Sensory part. 

Nuclei originis: 

(a) For N. glossopharyngeus. 

(aa) Superior ganglion (ganglion superius). 

(ab) Petrosal ganglion (ganglion petrosum). 

(b) For N. vagus. 



DISSECTION OF THE HEAD AND NECK 369 

(ba) Jugular ganglion (ganglion jugular e). 

(bb) Ganglion nodosum (ganglion nodosum) ("knotty" gan- 

glion). 
Nuclei terminates: 

(a) Nucleus of ala cinerea (nucleus alae cinereae). 

(b) Nucleus of tractus solitarius (nucleus tractus solitarii). 

(c) Commissural nucleus (nucleus commissuralis) (O. T. ganglion 

commissurale). 
Secondary paths: 

(a) From nuclei terminates through fibrae arcuatae internae to oppo- 

site stratum interolivare lemnisci and thence through lemniscus 
medialis to [ventro-] lateral nucleus of thalamus. 

(b) From nuclei terminates through lateral bundles of substantia 

reticularis alba of same and of opposite side to [ventro-] lateral 
nuclei of thalamus. 

(c) From nuclei terminates through medial portion of corpus resti- 

forme to nucleus fastigii and cortex vermis. 

Tertiary path: probably from [ventro-] lateral nucleus of thalamus 
through capsula interna and corona radiata to central gyri (somaes- 
thetic area). 

Conduction Paths of Cerebellar Peduncles. 

PATHS OF CORPUS RESTIFORME (0. T. INFERIOR PEDUNCLE). 

(a) Paths of corpus resti forme proper. 

(aa) Cerebellospinal fasciculus (fasciculus cerebellospinalis, or, 

better, fasciculus spinocerebellaris dorsolateralis) (0. T. 
direct cerebellar tract). 

(ab) External arcuate fibres (fibrae arcuatae externae ) = crossed 

and uncrossed medullated axones from nuclei funiculi 
cuneati et gracilis. 

(ac) Cerebello-olivary fibres (fibrae cerebelloolivares) , partly as- 

cending, partly descending. 

(ad) Medullated axones from nuclei laterales to cerebellum. These 

paths (aa, ab, ac, and ad] run into the cerebellum to end 
in the cortex of the vermis; they give off collaterals and 
some terminals to the nucleus fastigii, nucleus dentatus, 
nucleus emboliformis, and nucleus globosus as these are 
passed. 

(b) Paths of medial part of corpus restiforme. 

(ba) Ascending paths, corresponding to secondary paths from the 

nuclei terminates of the Nn. vagus, glossopharyngeus, ves- 
tibularis, et trigeminus to the nucleus fastigii and cortex 
vermis. 

(bb) Descending paths from nucleus fastigii to opposite nucleus 

N. vestibularis [Deitersi]. This connects at Deiters' nu- 
cleus with the path leading to the lateral funiculus of the 
spinal cord. 

PATHS OF BRACHIUM PONTIS (0. T. MIDDLE CEREBELLAR PEDUNCLE). 

(a) Cerebellopontal paths, from cortex of hemisphaerium cerebelli to 
nuclei pontis of same and of opposite side. 
24 



370 LABORATORY MANUAL OF HUMAN ANATOMY 




1C-' 



c, 



DISSECTION OF THE HEAD AND NECK 371 



Horizontal section through the right cerebral hemisphere cut at a distance of 61 mm. below its 
superior border ; natural size. 

AM, claustrum; C, cuneus; CA, hippocampus (comu ammonis) ; Cc(g), genu corporis callosi ; Ce, 
capsula externa ; Cg, gyrus dentatus ; Cia, pars frontalis capsulae internae ; Ci(g), genu capsulae internae ; 
Cing, horizontal bundle of the cingulum ; Cing(p), posterior bundle of the cingulum ; dp, pars occipi- 
talis capsulae internae ; Ctrl, retrolenticular portion of internal capsule ; cm, sulcus cinguli ; CO, centrum 
semiovale ; cop, commissura posterior cerebri ; Csc, gyrus subcallosus ; do, cornu posterius ventriculi 
lateralis ; FI, gyrus frontalis superior ; F z , gyrus frontalis medius ; F s , gyrus frontalis inferior ; / 1? sulcus 
rontalis superior ; / 2) sulcus frontalis inferior; F 3 (c), pars triangularis gyri frontalis inferioris ; Fli, 
fasciculus longitudinalis inferior; FM, fasciculus retroflexus Meynerti ; Fm', fasciculus inferior or 
minor of the fornix ; Gh, nucleus habenulae ; Gp, corpus pineale ; la, insula (pars anterior) ; Jp, insula 
(pars posterior) ; K, fissura calcarina ; K\.po, union of the flssura calcarina with the fissura parieto- 
occipitalis; LI, gyrus cinguli; L(i), isthmus gyri fornicati ; Ic, lamina cornea and fibres of the taenia 
semicircularis ; Lg, gyrus lingualis ; Ime, lamina medullaris lateralis nuclei lentiformis ; Imi, lamina 
medullaris medialis nuclei lentiformis ; Ims, lamina medullaris superficialis ; mFi, facies medialis gyri 
frontalis superioris ; NC, caput nuclei caudati ; NC', cauda nuclei caudati ; Ne, nucleus lateralis 
thalami ; NL^, NL, globus pallidus (of nucleus lentiformis) ; NL%, putamen (of nucleus lentiformis) ; 
0\, 02, gyri occipitales ; oa, sulcus occipitalis anterior of Wernicke ; OF, fasciculus occipito-frontalis ; 
oi, sulcus interoccipitalis ; Op,F 3 , pars opercularis gyrus frontalis inferioris ; OpR, Rolandic operculum ; 
Pa Th, pedunculus anterior thalami ; po, fissura parieto-occipitalis ; Pul, pulvinar ; ircl, cuneo-limbic 
fold; irplp, posterior parieto-limbic fold; RTh, radiatio occipito-thalamica [Gratioleti] ; S(p), ramus 
posterior fissurae cerebri lateralis Sylvii; S(v), ramus ascendens; sec, sinus corporis callosi; Sgc, sub- 
stantia grisea centralis; Sge, subependymal gray matter; H, gyrus temporalis superior; 7J>, gyrus 
temporalis medius ; ti, sulcus temporalis superior ; Tap, tapetum ; tec, taenia tecta ; Tga, anterior pillar 
of the fornix; TgV, ventriculus lateralis; Th, thalamus; Tp, gyrus temporalis transversus; tp, sulcus 
temporalis transversus ; V^, ventriculus tertius ; V, stripe of Vicq d'Azyr ; VA, fasciculus thalamo- 
mammillaris Vicq d'Azyri; TJ, cornu anterius ventriculi lateralis; Vsl, cavum septi pellucidi ; Zr t 
zona reticularis. (After J. Dejerine, Anatomie des Centres Nerveux, Paris, 1895, p. 408, Fig. 226.) 



372 LABORATORY MANUAL OF HUMAN ANATOMY 

(b) Pontocerebellar paths, from nuclei pontis to cortex of hemisphaerium 
cerebelli of same and of opposite side. 

PATHS OF BRACHIUM CONJUNCTIVUM (0. T. SUPERIOR CEREBELLAK PEDUNCLE). 

(a) Paths from nucleus dentatus cerebelli through brachium conjunctivum 

to tegmentum of cerebral peduncle, there to decussate in large part 
in the decussatio brachii conjunctivi, then to give off large numbers 
of collaterals to the nucleus ruber, and finally, joining the fibres of 
the lemniscus medialis, to end in the [ventro-] lateral nucleus of the 
thalamus. There it connects with the thalamocortical path to the 
central gyri (somaesthetic area). 

This path influences the spinal cord in at least two ways : 

(1) By collateral fibres which leave main axones soon after exit 
from the cerebellum and pass down to the spinal cord (ramus de- 
scendens of Ramon y Cajal). 

(2) Through the red nucleus which sends a path to the lateral 
funiculus. 

(b) Path from spinal cord to cerebellum running in Gowers' tract upward 

to pons and corpora quadrigemina, then hooking around N. tri- 
geminus and running, in velum medullare anterius, close to bra- 
chium conjunctivum, to cerebellar vermis. 

Conduction Paths of Diencephalon and Telencephalon. 

I. PROJECTION FIBRE SYSTEMS. 

These are the fibre systems which connect the gray matter of the 
telencephalon (pallium, nucleus caudatus, nucleus lentiformis, rhinen- 
cephalon) with lower parts of the nervous system (thalamus, brain- 
stem, spinal cord). 

(A) Ascending projection systems (corticopetal paths). 

(1) Uppermost neurone systems of general sensory path. The medul- 

lated axones pass from the cells in the [ventro-] lateral nucleus 
of the thalamus, chiefly through the posterior third of the 
capsula interna and corona radiata, to the cortex of the cen- 
tral gyri (somaesthetic area) ; a few fibres go through or around 
the nucleus lentiformis, and by way of the capsula externa to the 
cortex. 

(2) Upper part of visual conduction path. The medullated axones pass 

from the cells in the nucleus corporis geniculati laterale and pul- 
vinar thalami, through the radiatio occipitothalamica, to the 
cortex about the fissura calcarina. 

(3) Upper part of auditory conduction path. The medullated axones 

pass from the cells in the nucleus corporis geniculati medialis and 
nucleus colliculi inferior, by way of the posterior part of the 
capsula interna, lateralward to the gyrus temporalis superior 
(junction of third and fourth fifths), and adjacent gyri tem- 
porales transversi. 

(B) Descending projection systems (corticofugal paths). 

(1) Pyramidal tract (fasciculi pyramidales] , from large pyramidal 
cells of central gyri and lobulus paracentralis, through corona 
radiata and through knee and anterior two-thirds of occipital 
limb of capsula interna (head-movement fibres in front, arm 



DISSECTION OF THE HEAD AND NECK 373 

fibres in middle, and leg fibres behind), into basis pedunculi, to 
motor nuclei of cerebral nerves and to anterior horns of spinal 
cord. 

(2) "Accessory lernniscus" of v. Bechterew, from cortex to motor 

nuclei of cerebral nerves. 

(3) Frontal corticopontile path (fasciculus corticopontilis frontalis), 

from posterior part of frontal lobe, through frontal limb of 
capsula interna and through medial part of basis pedunculi 
(Arnold's bundle), to nuclei pontis. 

(4) Temporal corticopontile path (fasciculus corticopontilis tempo- 

ralis ) . 

(5) Occipitomesencephalic path (fasciculus occipitomesencephalica) 

(0. T. secondary optic radiation of Flechsig), fibres from visual 
sense area about fissura calcarina, downward through occipito- 
thalamic radiation to superior colliculus. 

(6) Projection fibre systems of central olfactory paths. 

(a) Hippocanipo-mammillary fibre system, going from cells in 
hippocampus, through fornix and columna for- 
nicis, to nuclei corporis mammillaris of same and 
of opposite side; there connecting with 

(aa) Principal mammillary fasciculus (fasciculus mam- 

millaris princeps), which divides into 

(aaa) Thalamomammillary fasciculus (fascicu- 

lus thalamomammillaris [Vicq d'Azyri]), 
going to nucleus anterior thalami, and 

(aab) Tegmental part of pedunculomammillary 

fasciculus (fasciculus pedunculomammil- 
laris, pars tegmentalis), to the tegmen- 
tum of the cerebral peduncle. 

(ab) Basilar part of pedunculomammillary fasciculus 

(fasciculus pedunculomammillaris, pars basilaris) 
(0. T. peduncle of mammillary body). 

II. ASSOCIATIVE FIBRE SYSTEMS. 

(A) Connecting different parts of same hemisphere. 

(a) Those with short axones, including the fibrae propriae of the gyri 

cerebri. 

(b) Those with long axones. 

(ba) Cingulum (cingulum) (" girdle"), in the gyrus cinguli and 

gyrus hippocampi. 

(bb) Superior longitudinal fasciculus (fasciculus longitudinalis 

superior), extending between lobus frontalis and lobus 

occipitalis. 
(be) Inferior longitudinal fasciculus (fasciculus longitudinalis 

inferior), between lobus occipitalis and more anterior 

parts of brain. 
(bd) Uncinate fasciculus (fasciculus uncinatus), between uncus 

and base of lobus frontalis. 

(B) Connecting the two hemispheres with each other (commissural fibre sys- 

tems). 

(a) Corpus callosum (corpus callosum) ("callous" or " hard" body). 

(b) Anterior commissure of cerebrum (commissura anterior [cerebri]). 

(c) Commissure of hippocampus (commissura hippocampi). 



FIG. 178. 



Stratum album profundum 



Nucleus 
N. oculomotorii 



Commissurae nuclei 
colliculi inferioris 



\ 



Fasciculus retroflexus 
[Meynerti] 



Lemniscus 
medialis 



Nucleus. 

colliculi" 

inferioris i 



Radix N - 

trochlearis 



Brachium 

conjunct! vumv 

Radix descendens-V 
N. trigemini \ 

Locus caeruleus \- 

Radix N. 

trigemini (mot.) 

Radix N. \ 
trigemini (sens.) 

Nucleus moto- 
rius princeps 
N. trigemini 




Nucleus N. 
trigemini 

(sens.)- 
Nucleus N. 
vestibuli - 
lateralis 
Corpus resti-... Jt 
forme 



Nucleus 
et radix 

N. ve*- 

tibuli 
Nucleus^ 

cochleae 
dorsalis 



Corpus restifonne__.. 



Tractus solitarius et 
nucleus alae cinereae 



Nucleus funiculi^ 
cuneati 

Fasciculus cuneatus 
Nucleus funiculi gracilis__ 

Fasciculus gracilis- 

The nuclei of the cerebral nerves. Dorsal surface of model. (From Sabin, An Atlas of 
the Medulla and Midbrain, Baltimore, 1901, Plate iii.) 



Corpus 
restifonne 
Radix N. 
facialis 
- (genu 

internum) 

Nucleus N. 

abducentis 



..Fasciculus 
longitu- 
dinalis 
medialis 



Nucleus 
olivaris 
inferior 

Nucleus N. 
hypoglossi 



DISSECTION OF THE HEAD AND NECK 



375 



ORGAN OF VISION (ORGAN ON VISUS). 

This includes the eyeball (bulbus oculi), the optic nerve (N. 
options), and the accessory organs of the eyeball (organa oculi 
accessories). The latter, including the extrinsic muscles of the 
eye, orbital fasciae, eyelids and eyebrows, conjunctiva, and lacri- 
mal apparatus, as well as the optic nerve, have already been 
studied. The eyeball itself should now be examined. 

The student should provide himself with several eyeballs 
from the ox and pig; some of these may be dissected fresh, 



FIG. 179. 

Linea visus (line or axis of vision) Axis optica (axis of the optical system, ocular axis) 

~~1 . Vertex corneae 
Camera oculi anterior (anterior chamber) 

Camera oculi posterior ^^TZ- H^-^^X^ Cornea. 
(posterior chamber) >O^\ I IV? \^V Iris 



Processus ciliaris . 



Zonula, ciliaris - ^ 
[Zinni] 



Lens crystallina-- 




,. Conjunctiva bulbi 
-M. ciliaris 
.-.Pars ciliaris retinae 
Ora serrata 
-Nodal point 

Equatorial 
diameter 



-Pars optica retinae 



Corpus vitreunv 



Papilla N.optici-- 
Excavatio papillae N. optici-' 



*-Fovea centralis of the macula lutea 



ill. __.N. opticus 



Schematic section in the horizontal meridian of the right eyeball. (After Toldt, Anat. Atlas, Wien, 

1903, 3 Aufl., p. 892, Fig. 1334.) 

others after hardening in formalin. Sections in different planes 
should be made of eyeballs hardened in formalin. These may 
easily be permanently preserved in formalin gelatin. The eye- 
balls should first be cleaned. Remove the conjunctiva, eye- 
muscles, fat, and capsule of Tenon. This is best done by grasp- 
ing the conjunctiva and fascia bu^bi with the point of the forceps 
close to the limbus corneae and snipping through them with fine 



376 LABORATORY MANUAL OF HUMAN ANATOMY 

sharp scissors, going right around the cornea in this way. All 
the soft parts may now be stripped off the sclera back as far as 
the N. opticus. Take two eyes, hardened in formalin, and divide 
one by a sagittal section into a medial and a lateral half, and the 
other by a coronal section through the equator into an anterior 
and a posterior half. With a sharp razor this can be easily 
accomplished in formalinized eyes without freezing. 
Ascertain the exact meaning of the following terms : 

(a) Anterior pole (polus anterior}. 

(b) Posterior pole (polus posterior}. 

(c) Equator (aequator}. 

(d) Meridians (meridiani}. 

(e) External axis of eyeball (axis oculi externa}. 

(f) Internal axis of eyeball (axis oculi interna}. 

(g) Optic axis (axis optica). 
(h) Line of vision (linea visus}. 

And of the two embryological terms : 

(i) Ophthalmic vesicle (vesicula ophthalmica} . 
(j) Ophthalmic cup (caliculus ophthalmicus} . 

Note that the eyeball possesses the following: 

(a) Fibrous tunic (tunica fibrosa oculi}. 

(aa) Cornea. 

(aft) Sclera. 
(6) Vascular tunic (tunica vasculosa oculi}. 

(ba} Chorioid coat (chorioidea} . 

(bb) Ciliary body (corpus ciliare}. 

(be} Iris (iris}. 

(c} Pigment layer (stratum pigmenti}. 
(d) True nervous portion of eye (retina}. 

(e} Anterior and posterior chambers (camera oculi anterior, posterior}, 
(f} Vitreous body (corpus vitreum}. 
(g} Crystalline lens (lens crystallina}. 
(h} Ciliary zonule (zonula ciliaris [Zinni]}. 

Fibrous Coat of Eye (Tunica fibrosa oculi). 

Make an incision with a very sharp knife through the sclera 
of an eyeball at the equator ; let the knife cut only as far as the 
black chorioidea, then lay it aside. Catch the edge of the sclera 
in forceps, and with sharp fine scissors cut through the sclera 
all the way around the eyeball, along the line of the equator. 
Raise the anterior and posterior segments of the sclera from 
the subjacent parts. In turning the anterior half forward, over- 
come the resistance met near the margin of the cornea, due to 
the attachment of the M. ciliaris to the deep surface of the sclera, 



DISSECTION OF THE HEAD AND NECK 



377 



with the probe or the blunt point of the closed forceps; on 
breaking through this resistance the so-called " aqueous humor" 
escapes. To separate completely the posterior segment of the 
sclera from the rest of the eyeball, cut through the fibres of the 

FIG. 180. 



Sinew radiation of the M. rectus superior __ 



Sclera 



Aa. and Vv. ciliares anteriores 
Circulus arteriosus major |, 



Angulus iridis 

Sinus venosus sclerae 
(canalis Schlemmi) 



Conjunctiva bulbi .._ 

Episcleral connective 
tissue with Aa. and Vv 

episclerales 
Lig. pectinatum iridis 

Rima cornealis (groove 
for the cornea) _ 



Limbus corneae 

(border of the 

cornea) 

Iris (facies._ 

anterior) 

Camera oculi 

anterior 
Cornea (sub- 
stantia propria 



Facies posterior 
corneae 
Epithelium 

corneae 

Lamina elastica 
anterior fBow- 

mani] 

Lamina elastica posterior [Bes- 
eemed] with the M. endo- 
thelium camerae anterioris 



Pars ciliaris retinae 
Stratum pigmenti retinae 




Pars optica retinae 
Ora serrata 



Chorioidea 

Spatium perichorioideale with the 
lamina suprachorioidea 




I .Fibrae meridional es [Brueckei] 

^.Fibrae circulares [Muelleri] 
.-Processus ciliaris 

^,. Fibrae zonulares 
. Zonula ciliaris [Zinni] 
g. Spatia zonularia 

Camera oculi posterior 



Epithelium lentis 
-.:- Capsula lentis 



substantia 
jorticalis 



M. ciliaris 



Jubstantia lentis 



M. sphincter pupillae 



Stroma iridis 

Facies posterior iridis with the 
stratum pigmenti 



The upper half of a section in the vertical meridian of the anterior part of the eyeball. 
(After Toldt, Anat. Atlas, Wien, 1903, 3 Aufl., p. 893, Fig. 1337.) 

N. opticus in a plane corresponding to the inner surface of the 
sclera. Place the denuded eyeball in a dish of water and study 
the sclera and cornea. 



378 



LABORATORY MANUAL OF HUMAN ANATOMY 



In the SCLEEA (0. T. sclerotic coat, or white of the eye) exam- 
ine the following : 

(a) Sulcus of the sclera (sulcus sclerae). 

Make a meridional incision through the sclerocorneal junction 
and note 

(b) Cleft for the cornea (rima cornealis). 

(c) Venous sinus of the sclera, or canal of Schlemm (sinus venosus sclerae 

[canalis Schlemmi, Lauthi]). 

(d) Brown layer (lamina fusca). 

To what is this due? 

(e) Perforated layer of sclera (lamina cribrosa sclerae). 

In the CORNEA study the following : 

(a) Ring of conjunctiva (annulus conjunctivae). 

(b) Vertex of cornea (vertex corneae). 

(c) Border of cornea (limbus corneae). 

(d) Anterior surface (fades anterior). 

(e) Posterior surface (fades posterior). 

Make a razor section or a frozen section through the cornea, 
and under the dissecting microscope observe 



A. and V. ciliaris anterior 

A. and V. conjunctivalis- 
posterior 



A. and V. conjuncti- 

valis anterior 
Sinus venosus V< 
sclerae (Canalis 
Schlemmi) 



FIG. 181. 

-M. rectus medialis 



A. and V. episcleralis 



V. vorticosa (vortex vein) 
A. ciliaris posterior longa 



A. and V. ciliaris pos- 
terior brevis 

Vessels of the va- 
^ gina N. optici 




Circulus anteri- 
ijor in 
cross-section 



N. opticus 

A. and V. cen- 
tralis retinae 

Scheme of the arrangement of blood-vessels in the eyeball. Horizontal section. (After 
Th. Leber.) (From Toldt, Anat. Atlas, Wien, 1903, 3 Aufl., p. 897, Fig. 1351.) 

(f) Epithelium of cornea (epithelium corneae). 

(ff) Anterior elastic layer (lamina elastica anterior [Bowmani]) (0. T. 

Bowman's membrane). 
(h) Proper substance (substantia propria). 



DISSECTION OF THE HEAD AND NECK 



379 



() Posterior elastic layer (lamina elastica posterior [Demoursi, Desce- 

meti]) (0. T. Descemet's membrane). 
(,;') Endothelium of anterior chamber (endothelium camerae anterioris). 

Vascular Coat of Eye (Tunica vasculosa oculi). 

In the CHORIOID COAT (chorioidea) study the following: 

(a) Suprachorioid layer (lamina suprachorioidea) . 

(b) Perichorioideal space (spatium perichorioideale) . 

(c) Vascular layer (lamina vasculosa). 

Observe the Vv. vorticosae. If the pigment be washed out with 
a camel's-hair brush, these will become very evident. 

(d) Choriocapillary layer (lamina choriocapillaris) (0. T. tunica Ruysch- 

iana) . 

Between (c) and (d) observe the Aa. ciliares posteriores breves. 

In the CILIARY BODY (corpus ciliare) the ciliary wreath (corona 
ciliaris) and the ciliary disk (orbiculus ciliaris) are to be studied. 
To expose the ciliary wreath make a coronal section through an 
eyeball a little in front of the equator, and remove cautiously the 
vitreous humor from the anterior segment of the eyeball. Ex- 
amine 

FIG. 182. 



- Orbiculus ciliaris 



Plicae ciliares 




.Corpus ciliare 

Processus ciliares 
Iris (facies posterior) 

__Aequator lentis (lens capsule 
separated off a little) 

Lens crystallina ( facies posterior) 

A part of the ciliary processes and ciliary folds , enlarged. (After Toldt, Anat. Atlas, Wien, 1903. 

3 Aufl., p. 895, Fig. 1342.) 

(a) Ciliary processes (processus ciliares). 

(b) Ciliary folds (plicae ciliares). 

With a camePs-hair brush wash out the pigment and note the 
exact disposition of the processes and folds. 

The ciliary wreath may be exposed from in front in another 
eyeball as follows : remove cornea with scissors at sclerocorneal 
junction. Make four meridional cuts through sclera and reflect 



380 LABORATORY MANUAL OF HUMAN ANATOMY 

its parts backward, separating each from the M. ciliaris; pin 
these down to the bottom of a cork-lined tray. Examine the iris 
and then cautiously remove it. 

In the ciliary disk (orbiculus ciliaris) examine 

(a) Ciliary muscle (M. ciliaris). 

(aa) Meridional fibres (fibrae meridionales [Brueckei]). 

(ab) Circular fibres (fibrae circulares [Mulleri]). 

These are best distinguished in a thin meridional section through 
the corpus ciliare under the microscope. 

(b) Ganglionic ciliary plexus (plexus gangliosus ciliaris}. 

Look for it at the junction of the chorioidea with the corpus 
ciliare. 

In the DIAPHRAGM OF THE EYE (iris) study 

(a) Pupillary margin (mar go pupillaris). 

(b) Ciliary margin (mar go ciliaris). 

(c) Anterior surface (fades anterior). 

(d) Posterior surface (fades posterior). 

FIG. 183. 

Orbiculus ciliaris, Annulus ciliaris 

Chorioidea ! i Iris (facies anterior) 

MM 



Margo ciliaris - 

(iridis) 



Annulus iridis major / / fcupilla 
Circulus iridis minor 'Annulus iridis minor 

The iris ("rainbow") of a clear gray eye, with the adjacent part of the sclerotic coat. Seen from in 
front. (After Toldt, Anat. Atlas, Wien, 1903, 3 Aufl., p. 896, Fig. 1347.) 

(e) Greater ring of iris (annulus iridis major), between iris and corpus 

ciliare. 
(/) Lesser ring of iris (annulus iridis minor), between ciliary zone (zona 

ciliaris} and pupillary zone (zona pupillaris} of iris. 
(g) Folds of iris (plicae iridis). 
(h) Pupil (pupilla). 

(i) Sphincter muscle of pupil (M. sphincter pupillae). 
(j) Stroma of iris (stroma iridis) . 
(k) Dilator muscle of pupil (M. dilator pupillae). 
(1) Pectinate ("comb-like") ligament of iris (Lig. pectinatum iridis) (0. 

T. pillars of the iris). Observe the relation of the fibres of this 

ligament to those of Descemet's lamina. 
(m) Spaces of Fontana at the angle of the iris (spatia anguli iridis [Fon- 

tanae]). 




DISSECTION OF THE HEAD AND NECK 381 

(n) Greater arterial circle (circulus arteriosus major), 
(o) Lesser arterial circle (circulus arteriosus minor). 

What is the pupillary membrane (membrana pupillaris) of foetal 
life? 

The ciliary nerves and ciliary arteries and the Vv. vorticosae 
should now be reviewed. (See pp. 277-281.) Examine espe- 
cially, at the back part of the eye, between the chorioid and the 
sclera, the passage of the Vv. vorticosae into the sclera; cut 
through these and observe the Aa. ciliares posteriores breves 
coming from the sclera to the chorioid. 

Layer of Pigment (Stratum pigment!) . 

In an eyeball which has had its sclera and cornea removed 
and is under water, remove the chorioidea piecemeal, so as to 
expose the stratum pigmenti and the retina. Note that the 
stratum pigmenti is divisible into three parts : 

(a) Pigment layer of retina (stratum pigmenti retinae). 

(b) Pigment layer of ciliary body (stratum pigmenti corporis ciliaris). 

(c) Pigment layer of iris (stratum pigmenti iridis). 

Retina. 

In this study the following : 

(a) Optic part of retina (pars optica retinae). 

(aa) Serrated edge (ora serrata). 

(b) Ciliary part of retina (pars ciliaris retinae). 

(c) Papilla of optic nerve (papilla N. optici). 

(d) Excavation of papilla of optic nerve (excavatio papillae N. optici). 

(e) Yellow spot (macula lutea). 

Present in man, but not in the ox or sheep. 
(/) Central fovea (fovea centralis). 
(g) Blood-vessels of the retina (vasa sanguinea retinae). (Fig. 184.) 

The blood-vessels of the retina may now be studied. The 
student should sometime control this study by an examination 
of the eye-ground of a living person through the ophthalmoscope. 
Note 

(a) Superior arteriole [venule] of temporal retina (arteriola [venula] 

temporalis retinae superior). 

(b) Inferior arteriole [venule] of temporal retina (arteriola [venula] 

temporalis retinae inferior). 

(c) Superior arteriole [venule] of nasal retina (arteriola [venula] nasalis 

retinae superior). 

(d) Inferior arteriole [venule] of nasal retina (arteriola [venula] nasalis 

retinae inferior). 



382 LABORATORY MANUAL OF HUMAN ANATOMY 

(e) Superior macular arteriole [venule] (arteriola [venula] macularis 
superior). 



FIG. 184. 



Arteriola and venula temporalis retinae 
superior 



Arteriola and venula nasalis 
retinae superior 



Arteriola and venula 
retinae medialis 



Arteriola and venula 
nasalis retinae inferior 



Arteriola and venula temporalis 
retinae inferior 




Papilla N. optici 



Fovea centralis of the 
macula lutea 



Venula macularis superior 
Venula macularis inferior 



The fundus of the eye. with the retinal vessels ; in the left normal eye of a dark-haired young man, 
as seen with the ophthalmoscope. Erect image. (After E. v. Jager, in Toldt, Anat. Atlas, Wien, 1903, 
3 Aufl., p. 898, Fig. 1355.) 



(f) Inferior macular arteriole [venule] (arteriola [venula] macularis 

inferior). 

(g) Medial arteriole [venule] of retina (arteriola [venula] retinae me- 

dialis). 



Vitreous Body (Corpus vitreum). 

In an eyeball no longer fresh, one that has been kept for 
from one to four days, divide the tunicae of the eye at the 
equator, reflect the cut edges backward and forward, and, as 
Anderson Stuart has suggested, allow the " eye-kernel" (corpus 
vitreum + lens crystallina) to slip out into a vessel filled with 
clean water. Transfer it for a few minutes to a strong solution 
of picrocarmin, then wash in water. The membrana hyaloidea, 
capsula lentis, and zonula ciliaris [Zinni] will be stained red, 
and their connections are easily visible. 

In the vitreous body study 



(a) Hyaloid canal (canalis hyaloideus) (0. T. canal of Stilling). 

(b) Hyaloid fossa (fossa hyaloidea) (0. T. fossa patellaris). 

(c) Hyaloid membrane (membrana hyaloidea). 

(d) Vitreous stroma (stroma vitreum). 

(e) Vitreous humor (humor vitreus). 




DISSECTION OF THE HEAD AND NECK 383 

Where does the hyaloid artery (A. hyaloidea) run in the 
embryo ? 

Ciliary Zonule (Zonula ciliaris [Zinni]). (See Figs. 179 and 180.) 
How is this formed? What is its relation to the corpus vit- 
reum and to the lens? What part of it is known as the " sus- 
pensory ligament of the lens"? Study 

(a) Zonular fibres (fibrae zonulares). 

(b) Zonular spaces (spatia zonularia) (0. T. canal of Petit). 

The well-known saccular appearance of these spaces may be 
easily produced if the point of a fine blow-pipe be inserted into 
them and they be inflated with air. 

FIG. 185. 



Facies anterior.. _^B mk - Facies posterior 




Polus anterior-'""!!!;" """ T p olus posterior 

''Axis lentis 



Aequator lentiscT 

The terms used for the orientation of the lens. (After Toldt, Anat. Atlas, Wien, 1903, 3 Aufl., 

p. 900, Fig. 1363.) 

Crystalline Lens (Lens crystallina). 

Cut through the fibrae zonulares of the zonula ciliaris [Zinni] 
and remove the lens. Examine the following : 

(a) Capsule of lens (capsula lentis). 

(b) Anterior pole of lens (polus anterior lentis}. 

(c) Posterior pole of lens (polus posterior lentis). 

(d) Anterior surface of lens (fades anterior lentis). 

(e) Posterior surface of lens (fades posterior lentis). 

(f) Axis of lens (axis lentis). 

(g) Equator of lens (aequator lentis) (0. T. circumference). 
(h) Radii of lens (radii lentis). 

Now divide the anterior part of the capsula lentis with a 
sharp knife and press the lens out through the opening. Study 
the stained capsule as it floats in water. Press the substance of 
the lens (substantia lentis) between the finger and thumb, and 



384 LABORATORY MANUAL OF HUMAN ANATOMY 

note that the cortical substance (substantial corticalis) is soft 
while the central part or nucleus of the lens (nucleus lentis) is 
firmer. Place a bit of the lens in thirty-three and one-third 
per cent, alcohol for twenty-four hours, then tease it apart and 
under the microscope examine 

(a) Epithelium of lens (epithelium lentis). 

(b) Fibres of lens (fibrae lentis). 

Chambers of Eyeball (Camerae oculi). 
These are two in number : 

(a) Anterior chamber of eyeball (camera oculi anterior). 

(aa) Angle of iris (angulus iridis) (0. T. iridocorneal angle). 

Why is this of great importance ? 
(6) Posterior chamber of eyeball (camera oculi posterior). 

Study the form, position, and boundaries of each. Both con- 
tain the so-called aqueous humor. 



ORGAN OF HEARING (ORGAN ON AUDITUS). 
This consists of several parts, viz. : 

(a) Internal ear (awn's interna). 

(aa) Membranous labyrinth (labyrinthus membranaceus) . 

(ab) Osseous labyrinth (labyrinthus osseus). 

(b) Middle ear. 

(ba) Cavity of tympanum (cavum tympani). 

(bb) Eustachian tube (tuba auditiva [Eustachii]). 
(be) Mastoid cells (cellulae mastoideae). 

(c) External ear (auricula) (0. T. pinna). 

The dry temporal bone should be thoroughly reviewed in con- 
nection with the study of the organ of hearing. The external ear 
has been studied already. (Cf. p. 258.) 

Take a temporal bone, preferably one with the auricula still 
attached. to it; saw off the squama temporalis by making a 
horizontal cut at the level of the root of the zygomatic process ; 
remove roof and anterior wall of the external acoustic meatus 
piecemeal, with the aid of bone-forceps and chisel, until the mem- 
brane of the tympanum is exposed. 



DISSECTION OF THE HEAD AND NECK 



385 



External Acoustic Meatus (Meatus acusticus externus). 

Examine the external acoustic meatus (meatus acusticus ex- 
ternus) thus opened, and compare it with a dry temporal bone, 
and if possible with a macerated specimen showing the carti- 
laginous part well. Study 

(a) External acoustic porus (porus acusticus externus). 

(b) Tympanic incisure (incisura tympanica [Eivini}). 

(c) Cartilaginous external acoustic meatus (meatus acusticus externus 

cartilagineus) . 

(d) Cartilage of acoustic meatus (cartilago meatus acustici). 

(da) Notches in cartilage of external meatus (incisurae cartilagi- 

nis meatus acustici externi [Santorini]). 

(db) Layer of tragus (lamina tragi). 



FIG. 186. 



Incus 




Canalis semicircularis lateralis 
Canalis semicircularis superior 
Vestibulum labyrinthi 

/ 

Basis stapedis 

/ Apertura vestibularis cochleae 



Area vestibula- 
ris superior 

.Grista trans- 



Meatus acus- 
ticus exter- 
nus 



s Tractusspiralisforaminosus 
Cochlea (scala tympani) 

Lamina spirnlis (ossea and 
membranacea ) 



I Jlulbus V. jugularis supcric 

Membrana tympani Cavum tymp'an'i 



Nearly frontal section through the outer, middle, and inner ear. (After Toldt, Anat. Atlas, 
Wien, 1903, 3 Aufl., p. 932, Fig. 1447.) 



Cavity of Tympanum (Cavum tympani). 

This cavity (cavum tympani) should next be studied. Make 
an opening through the roof of the tympanum (tegmen tympani) 
just lateral from the eminentia arcuata (due to the superior 
semicircular canal) and about one centimetre in front of the 
angulus superior pyramidis. The opening leads into the tym- 
panic antrum of the mastoid wall of the cavity of the tympanum. 
Enlarge the opening carefully with bone-forceps, gradually re- 
moving piece by piece the whole roof or tegmental wall (paries 

25 



386 



LABORATORY MANUAL OF HUMAN ANATOMY 



tegmentalis). Note that the epitympanic recess (recessus epi- 
tympanicus} is opened into; observe its cupolar portion (pars 
cupularis). The general shape of the cavity and walls of the 
tympanum may easily be remembered by thinking of a miniature 
cigar-box obliquely placed inside the temporal bone. Study the 
following : 

(a) Jugular wall (paries jugularis) (0. T. floor). 

(ab) Styloid prominence (prominentia styloidea). 

(b) Mastoid wall (paries mastoidea) (0. T. posterior wall). 

(ba) Tympanic antrum (antrum tympanicum) (0. T. mastoidal 

antrum). 

(bb) Prominence of lateral semicircular canal (prominentia canalis 

semicircularis lateralis). 
(be) Prominence of facial canal (prominentia canalis facialis). 

(bd) Pyramidal eminence (eminentia pyramidalis). 

(be) Fossa of incus (fossa incudis). 

(bf) Posterior sinus (sinus posterior). 

(bg) Tympanic aperture of canaliculus of chorda (apertura tym- 

panica canaliculi chordae). 

(c) Carotid wall (paries carotica) (0. T. anterior wall). 



FIG. 187. 



Prominentia canalis semicircularis lateralis 



Eminentia pyramidalis, 
Fenestra vestibuli i 
Processus cochleariformis 

Semicanalis M. tensoris tympani ' 

Semicanalis tubae auditivae \ 



Antrum tympanicum 

Canal for the M. stapedius 



Canalis 
caroticw 




.Margo occipitalis 



Canalis facialis 
(FaUoppii) 



^Cellulae mas- 
toideae 



Sulcus promontorii ; \ 
Cavum tympani / 

Promontorium i 
Fossula fenestrae cochlea^ 



Incisura mastoidea 



The medial wall, paries labyrinthicus, of the left bony tympanic cavity, and the mastoid cells, 
cettulae mastoideae, shown in a section through the mastoid process and the anterior part of the petrous 
part of the temporal bone. Seen from the anterior and lateral side. (After Toldt, Anat. Atlas, Wien, 
1903, 3 Aufl., p. 927, Fig. 1432.) 



(d) Labyrinthic wall (paries labyrinthicus) (0. T. inner wall). (Fig. 
187.) 

(da) Fenestra ("window") of vestibule (fenestra vestibuli) (0. T. 

fenestra ovalis). 

(daa) Fossula of fenestra of vestibule (fossula fenestrae 
vestibuli). 

(db) Promontory (promontorium) . 



DISSECTION OF THE HEAD AND NECK 



387 



(dba) Sulcus of promontory (sulcus promontorii). 

(dbb) Subiculum ("support") of promontory (subiculum 

promontorii). 

(dc) Sinus of tympanum (sinus tympani). 

(dd) Fenestra ("window") of cochlea (fenestra cochleae] (0. T. 

fenestra rotunda). 

(dda) Fossula of fenestra of cochlea (fossula fenestrae 

cochleae). 

(ddb) Crest of fenestra of cochlea (crista fenestrae coch- 

leae). 

(de) Cochleariform process (processus cochleariformis). 
Observe the mastoid cells (cellulae mastoideae) and the tympanic 

cells (cellulae tympanicae}. 
(e) Membranous wall (paries membranaceus) (0. T. outer wall). 

This consists largely of the membrane of the tympanum, which 
should now be studied. 



FIG. 188. 



Margo occipitalis- 
Sulcus sigmoideus~ 




Cellulae mastoideae 



'Membrane and proc- 
esses in the re- 
cessus epitympani- 
cus and in the an- 
trum tympanicum 
Cms longum 
incudis 

Manubrium mallei 
Membrana tympani 

Pars tympanica ossis 

temporaUs 
** Canalis facialis 

(Fattoppii) 
^Processus styloideus 



Processus mastoideus 



The lateral wall, paries membranaceus, of the left tympanic cavity, and the entrance to the mastoid 
cells. The antrum tympanicum contains branching connective -tissue strands. Seen from the medial 
side. (After Toldt, Anat. Atlas, Wien, 1903, 3 AufL, p. 927, Fig. 1433.) 

Membrane of the Tympanum (Membrana tympani) (O. T. Drum- 
head). (Figs. 186, 188, and 191-193.) 
Examine 

(a) Flaccid part (pars flaccida) (0. T. Shrapnell's membrane). 

(b) Tense part (pars tensa). 

(c) Border of membrane of tympanum (limbus membranae tympani). 

(d) Anterior malleolar fold (plica malleolaris anterior). 

(e) Posterior malleolar fold (plica malleolaris posterior). 

These two folds are sometimes called " Prussak's striae." 
(/) Malleolar prominence (prominentia malleolaris). 
(g) Malleolar stria (stria malleolaris). 

(h) Umbo ("prominent part") of tympanic membrane (umbo mem- 
branae tympani). 
(i) Cutaneous layer (stratum cutaneum). 



388 



LABORATORY MANUAL OF HUMAN ANATOMY 



(j) Fibrocartilaginous ring (annulus fibrocartilagineus) . 
(k) Radiate layer (stratum radiatum). 
(1) Circular layer (stratum circulare). 
(m) Mucous layer (stratum mucosum). 

Tympanic Mucous Membrane. 

This membrane (tunica mucosa tympanica) presents a num- 
ber of folds and recesses. Examine 

FIG. 189. 



M. tensor tympani 





Tuba 

Memb. tymp. aitdi- 
Meatus acusticus externus tiva 

The cavum tympani and membrana tympani. A part of the meatus acusticus externus and the 
tuba auditiva are seen from in front, and somewhat from above and the side. (From Gegenbaur, Lehrb. 
der Anat. des Mensch., Leipzig, 1899, 7 Aufl., Bd. II. p. 619, Fig. 730.) 



(a) Posterior malleolar fold (plica malleolaris posterior). 

(b) Anterior malleolar fold (plica malleolaris anterior). 

(c) Anterior recess of membrane of tympanum (recessus membranae 

tympani anterior). 

(d) Superior recess of membrane of tympanum (recessus membranae 

tympani superior). 

(e) Posterior recess of membrane of tympanum (recessus membranae 

tympani posterior). 

(f) Fold of anvil (plica incudis). 

(g) Fold of stirrup (plica stapedis). 

(h) Secondary membrane of tympanum (membrana tympani secundaria). 

Are any tympanic glands (Gl. tympanicae) visible? 

Auditory Ossicles. 

These small bones (ossicula auditus) are three in number, 
stirrup (stapes], anvil (incus), and hammer (malleus). 
In the stapes study 

(a) Head of stirrup (capitulum stapedis). 

(b) Anterior limb (crus anterius). 



DISSECTION OF THE HEAD AND NECK 



389 



(c) Posterior limb (cms posterius}. 

(d) Base of stirrup (basis stapedis) (0. T. foot-piece). 



Incisura tympanica (Rivini) 
Pars flaccida membra nae tympani 

Plica membranae tympani 
anterior 

Spina tympanica major ^^ 

Fissura pctroti/mpanica 
(Glaseri) 

Prominentia malleolaris 
Limbus membranae tympani 

Stria malleolaris^ 
Umbo membranae tympani 



FIG. 190. 

^nr V : $|L Plica membranae tympani posterior 
Spina tympanica, minor 



Meatus auditorius externus 



Limbus membranae tympani 



: .Pars tensa membranae 
tympani 



'~ Oanalis fadalis (Fattoppii) 




The lateral surface of the left tympanic membrane (suface towards the meatus acusticus externus; 
the latter has been removed by a saw-cut parallel and close to the tympanic membrane). (After Toldt. 
Anat. Atlas, Wien, 1903, 3 Aufl., p. 924, Fig. 1420.) 

In the incus study 

(a) Body (corpus incudis). 

(b) Long limb (crus longum). 

(ba) Lenticular process (processus lenticularis) . 

(c) Short limb (crus breve). 

FIG. 191. 

Plica malleolaris anterior Chorda tympani 



Lig. mallei superius 
Recessus epitympanicus - 
rapitulum mallei ' 

Plica malleolaris posterior. 



Recessus membranae tympani' 
posterior 




Recessus membranae tympani anterior 

^Tubaauditiva 

--Insertion of the M. tensor tympani 

-Manubrium mallei 
Membrana tympani 



Canalis facial is (Fattoppii)' 

Opening of the recessus membranae tympani superior 

The medial surface and the anterior and posterior recesses of the tympanic membrane, brought into 
view by a saw-cut through the tympanum close to and parallel to the membrane and by removal of the 
anvil. (After Toldt, Anat. Atlas, Wien, 1903, 3 Aufl., p. 924, Fig. 1421.) 



In the malleus study 

(a) Handle of hammer (manubrium mallei). 

(b) Head of hammer (capitulum mallei}. 



390 



LABORATORY MANUAL OF HUMAN ANATOMY 



(c) Neck of hammer (collum mallei). 

(d) Lateral process (processus lateralis) (0. T. processus brevis). 

(e) Anterior process (processus anterior [Folii]) (0. T. processus gra- 

cilis). 



Joints and Ligaments of the Auditory Ossicles, 
Study the following: 

Joints (Articulationes ossiculorum auditus). 

(a) Joint between anvil and hammer (articulatio incudomalleolaris) . 

(b) Joint between anvil and stirrup (articulatio incudostapedia) . 

(c) Junction of stirrup and tympanum (syndesmosis tympanosta- 

pedia). 



FIG. 192. 



Posterior wall of the apex 
of the recess (fold of mucous membrane) 
Apex of the recess / 

Lig. mallei superius. 

Capitulum mallei in longitudinal ^ 
section 



Plica incudis 

Cms longum incudis,. 

Insertion of the M. tensor. 

tympani 

Processus lenticularis - 



Manubrium mallei 
Stratum mucosum'' 
Substantia propria-'" 



Membrana 
tympani 



Annulus fibro- 
cartilagineus 

Sulcus tympanicus/ 




Recessus epitympanicus 



.Lig. mallei laterale 



,__ Recessus membranae tympani 
superior 

'~*~ - Pars flaccida membranae tympani 

~"~--Prominentia malleolaris 
: Umbo membranae tympani 

~^-Meatus auditorius extern us 

-Stratum cutaneum of the drum 
membrane 



Frontal section of the left tympanic membrane and of the adjacent part of the external auditory 
passage, meatus acusticus externus, made after hardening in chromic acid and alcohol and decalcifica- 
tion with hydrochloric acid. The section passes through the head of the malleus and in front of the 
manubrium mallei. Seen from in front. (After Toldt, Anat. Atlas, Wien, 1903, 3 Aufl., p. 925, Fig. 1423.) 

Ligaments (Ligg. ossiculorum auditus). 

(a) Anterior ligament of hammer (Lig. mallei anterius). 

(b) Superior ligament of hammer (Lig. mallei superius). 

(c) Lateral ligament of hammer (Lig. mallei laterale) (0. T. external 

ligament). 

(d) Superior ligament of anvil (Lig. incudis superius). 

(e) Posterior ligament of anvil (Lig. incudis posterius). 

(f) Obturator membrane of stirrup (membrana obturatoria [sta- 

pedis]). 

(g) Annular ligament of base of stirrup (Lig. annulare baseos sta- 

pedis). 




I 

Basis stapedis 



DISSECTION OF THE HEAD AND NECK 391 

(h) Fixing- muscle of the base of the stapes (M. fixator baseos sta- 

pedis). 

Muscles of Auditory Bones. 

These muscles (musculi ossiculorum auditus) are two in 
number : 

(a) Tensor muscle of tympanum (M. tensor tympani). 

(b) Stapedius muscle (M. stapedius). 

Study form, position, origin, insertion, action, and innerva- 
tion of each. 

FIG. 193. 

Capitulum mallei, ^^^^^^ 

'St" ^Ak Crus breve 

Spina tympanica minor -| WJft f Incudis 

Processus anterior <Folii)-J8C ^A ^P lo " gum ' 

Processus laterali 

Insertio M. tensor tympani 
Manubrium mallei 

The cavum tympani with the membrana tympani and the ossicula auditus. Only that part of the 
cavum tympani supporting the membrana tympaiii is represented. ( From Gegenbaur, Lehrb. der Anat. 
des Mensch., Leipzig, 1899, 7 Aufl., Bd. ii. p. 615, Fig. 728.) 

The student should next review certain structures previously 
studied, viz, the chorda tympani (see p. 264 and Figs. Ill and 
115), the plexus tympanicus and the N. tympanicus (see p. 271), 
and the tuba auditiva [Eustachii] (see pp. 293 and 296). 

The study of the internal ear is very difficult. Much can be 
learned by fastening a temporal bone in a vice and chiselling 
cautiously until the osseous labyrinth is exposed. The temporal 
bone of a new-born babe or of a younger foetus will be found 
very helpful for study. The labyrinth of a guinea-pig and an 
embryo pig will also well repay study. In the museum, the ex- 
quisite preparations of isolated labyrinths, Wood's metal corro- 
sions, and models are available for study. The student should 
use these and should study his atlases and good descriptive 
texts in connection with them. 

Osseous Labyrinth (Labyrinthus osseus). 

Here the student should study successively the vestibule (ves- 
tibulum), the snail-like body (cochlea), and the internal acoustic 
meatus (meatus acusticus internus). 



392 



LABORATORY MANUAL OF HUMAN ANATOMY 



In the vestibulum examine the following : 

(a) Spherical recess (recessus sphaericus) (0. T. fovea hemisphaerica), 

(V) Elliptical recess (recessus ellipticus) (0. T. fovea hemielliptica). 

(c) Crest of vestibule (crista vestibuli). 

(d) Pyramid of vestibule (pyramis vestibuli}. 

(e) Cochlear recess (recessus cochlearis). 

(f) Perforated spots (maculae cribrosae). 

(fa) Superior (macula cribrosa superior). 

(fb) Middle (macula cribrosa media). 

(fc) Inferior (macula cribrosa inferior). 

(g) Osseous semicircular canals (canales semicirculares ossei). 

(ga) Superior (canalis semicircular is superior). 

(gb) Posterior (canalis semicircularis posterior). 

(gc) Lateral (canalis semicircularis lateralis) (0. T. external). 



Ampulla ossea superior 



Canalis semicircularis, 
superior 



Recessus ellipticus v 



Ampulla ossea. 
lateralis 



Canalis semi- 
circularis 
lateralis 



Canalis semi- 
circularis 
posterior 



FIG. 194. 



Apertura interna aquaeductus vestibuli 

Crista vestibuli with the macula cribrosa superior 
/ Canalis facialis (Falloppii) 

Recessus sphaericus with the 
macula cribrosa media 



Cochlea 



__Scala tympani 




Opening of the crus commune 

Ampulla ossea posterior 

Macula cribrosa inferior \ 
Fenestra cochleae 



Lamina spiralis ossea 
Scala vestibuli 

Recessus cochlearis 
Apertura interna canaliculi cochleae 

The bony labyrinth of the right ear, seen from in front. The lateral wall of the vestibule has been 
removed and the semicircular canals opened up in their entire length. (After Toldt, Anat. Atlas, Wien 
1903, 3 Aufl., p. 930, Fig. 1442.) 



(h) Osseous ampullae (ampullae osseae). 

(ha) Superior (ampulla ossea superior). 

(hb) Posterior (ampulla ossea posterior). 

(he) Lateral (ampulla ossea lateralis). 
(i) Ampullary limbs (crura ampullaria). 

(ia) Common limb (crus commune). 

(ib) Simple limb (crus simplex). 

In the cochlea study 

(a) Cupola (cupula cochleae). 

(b) Base (basis cochleae). 

(c) Spiral canal of cochlea (canalis spiralis cochleae), 



DISSECTION OF THE HEAD AND NECK 393 

(d) Modiolus. 

(da) Base of modiolus (basis modioli). 

(db) Shelf of modiolus (lamina modioli). 

(e) Osseous spiral shelf (lamina spiralis ossea). 

(ea) Hooklet of spiral shelf (hamulus laminae spiralis). 

(f) "Staircase" of vestibule (scala vestibuli). 

(g) "Staircase" of tympanum (scali tympani). 

(h) Helicotrema (helicotrema) (" pore of the helix"). 

(i) Secondary spiral shelf (lamina spiralis secundaria). 

(j) Spiral canal of modiolus (canalis spiralis modioli). 

(k) Longitudinal canals of modiolus (canales longitudinales modioli). 

FIG. 195. 



194 




The labyrinthus membranaceus of the right internal ear of a human embryo at the fifth month, 

seen from the medial side. 

1-5, utriculus ; 2, recessus utriculi ; 3, macula acustica utriculi ; A, sinus posterior ; 5, sinus superior ; 
6, ampulla membranacea superior ; 7, ampulla membranacea lateralis ; 8, ampulla membranacea pos- 
terior ; 9, ductus semicircularis superior ; 10, ductus semicircularis posterior ; 11, ductus semicircularis 
lateralis; 12, widened mouth of crus simplex of the lateral semicircular canal opening into the 
utriculus ; 13, sacculus ; Ik, macula acustica sacculi ; 15, ductus endolymphaticus ; 16, ductus utriculo- 
saccularis ; 17, ductus reunions ; 18, caecum vestibulare of ductus cochlearis ; 19, ductus cochlearis ; 20, 
N. facialis; 21-2!,, N. acusticus; 21, N. vestibuli; M, N. saccularis; 23, N. ampullaris inferior: .",. X. 
cochleae ; 25, distribution of N. cochleae within the lamina spiralis ossea. (After G. Retzius, as slightly 
modified by A. Rauber. ) 

In the meatus acusticus internus study 

(a) Internal acoustic opening (poms acusticus internus). 

(b) Bottom of internal acoustic meatus (fundus meatus acustici interni). 

(ba) Transverse crest (crista transversa). 

(bb) Area of facial nerve (area N. facialis). 
(be) Area of cochlea (area cochleae). 

(bca) Foraminous spiral tract (tractus spiralis forami- 

nosus). 
(bd) Superior vestibular area (area vestibularis superior). 



394 LABORATORY MANUAL OF HUMAN ANATOMY 

(be) Inferior vestibular area (area vestibularis inferior). 

(bf) Isolated foramen (foramen singulare). 

Membranous Labyrinth (Labyrinthus membranaceus). (Vide Fig. 

I95-) 1 

In the membranous labyrinth the following structures are to 
be studied : to make out some of them, sections should be exam- 
ined under a hand-lens or the dissecting microscope. The whole 
internal ear is simple if approached from the embryological side. 
(Cf. Kollmann, Minot, McMurrich, et al.) 

(a) Endolymphatic duct (ductus endolymphaticus) . 

(b) Endolymphatic sac (saccus endolymphaticus). 

(c) Utriculosaccular duct (ductus utriculosaccularis) . 

(d) Utricle (utriculus). 

(e) Semicircular ducts (ductus semicirculares) . 

(ea) Superior (ductus semicircularis superior). 

(eb) Posterior (ductus semicircularis posterior). 

(ec) Lateral (ductus semicircularis lateralis) (0. T. external). 

(f) Membranous ampullae (ampullae membranaceae) . 

(1) Ampullary sulcus (sulcus ampullaris). 

(2) Ampullary crest (crista ampullaris). 

(fa) Superior (ampulla membranacea superior). 

(fb) Posterior (ampulla membranacea posterior). 

(fc) Lateral (ampulla membranacea lateralis). 

(g) Saccule (sacculus). 

(h) Uniting duct (ductus reuniens [ Henseni] ) (0. T. canalis reuniens). 
(i) Acoustic spots (maculae acusticae). 

(ia) In utricle (macula acustica utriculi). 

(ib) In saccule (macula acustica sacculi). 
(j) Ear-stones (otoconia). 
(k) Endolymph (endolympha). 
(1) Perilymph (perilympha). 

(m) Perilymphatic space (spatium perilymphaticum) . 
(n) Perilymphatic ducts (ductus perilymphatici) . 

(o) Cochlear duct (ductus cochlearis) (0. T. membranous cochlea, or 
scala media). 

(oa) Cupular blind sac (caecum cupulare). 

(ob) Vestibular blind sac (caecum vestibular e) . 

(oc) Basilar layer (lamina basilaris). 

(od) Vestibular membrane of Reissner (membrana vestibularis 
[Reissneri]) . 

(oe) Spiral ligament of cochlea (Lig. spirale cochleae). 

(of) Spiral prominence (prominentia spiralis). 

(og) Vascular stripe (stria vascularis). 

'For an. account of the blood supply of the inner ear, consult " The Distri- 
bution of the Blood-vessels in the Labyrinth of the Ear of Sus scrofa domes- 
ticus," by G. E. Shambaugh, in Decennial Publications, vol. x., of the University 
of Chicago, Univ. of Chic. Press, 1903. 



DISSECTION OF THE HEAD AND NECK 



395 



(P) 



(oh) Spiral sulcus (sulcus spiralis). 

(oi) Tympanic lip (labium tympanicum) . 

(oia) Openings for nerves (foramina nervosa). 
(oj) Vestibular lip (labium vestibulare). 
(ok) Spiral ganglion of cochlea (ganglion spirals cochleae), 
(ol) Spiral organ of Corti (organon spirale [Cortii]). (Fig. 197.) 
Vessels of internal ear (vasa auris internae). (Cf. articles by Sieben- 
mann and by Shambaugli. ) 

FIG. 196. 




Section through the cochlear region of the labyrinthus osseus et membranaceus of a guinea-pig. 

I, scala vestibuli ; m, labium vestibulare of the limbus ; w, sulcus spiralis ; o, medullated peripheral 
fibres arising from cells in the ganglion spirale and being distributed to the organon spirale (Cortii) ; 
p, perikaryons in the ganglion spirale ; q, blood-vessel ; a, bone ; b, membrana vestibularis (Reissued i ; 
DC, ductus cochlearis ; d, Corti's membrane ; /, prominentm spiralis ; h, ligamentum spirale cochleae ; 
i, lamina basilaris ; k, scala tympani. (After A. A. Boehm and M. von Davidoff, Lehrbuch der Histologie 
des Menschen, etc., Wiesb., 1895, S. 362, Fig. 243.) 

Arteries. 

(pa) Internal auditory artery (A. auditiva interna). 

Of what is it a branch? 
(paa) Vestibular rami (rami vestibulares) . 



396 



LABORATORY MANUAL OF HUMAN ANATOMY 



(pab) Cochlear ramus (ramus cochleae). 
(pac) Arterial glomeruli of cochlea (glomeruli arteriosi 
cochleae). 



Veins. 



(pb) Internal auditory veins (Vv. auditivae internae). 

Of what are they tributaries? 
(pba) Spiral vein of modiolus (V. spiralis modioli). 

(pbaa) Prominent vessel (vas prominens). 
(pbb) Vestibular veins (Vv. vestibulares) . 
(pbc) Vein of aqueduct of vestibule (V. aquaeductus 

vestibuli). 
(pbd) Vein of canaliculus of cochlea (V. canaliculus 

cochleae). 

FIG. 197. 



71 




Spiral organ of Corti of the ductus cochlearis in transverse or radial section. 

re, medullated distal processes of bipolar nerve cells in ganglion spirale ; /, foramen nervosum in 
labium tympanicum giving passage to a bundle of the cochlear nerve fibres ; tb, tympanal covering of 
lamina basilaris ; vs, vas spirale ; iS, internal supporting cells which on the left side are continuous 
with the epithelium of the sulcus spiralis ; p, internal pillar with an inner basal cell (5) next to it ; p', 
external pillar with its external basal cell, b' ; 1,2,3, Deiters' supporting cells with phalangeal processes 
arriving at the surface of Corti's organ, there attached to the lamina reticularis, r ; II, Hensen's sup- 
porting cells which diminish in height toward the right side of the figure and are continuous with C, 
the cells of Claudius ; k, epithelial cells of the so-called " layer of granules " ; i, internal hair cell, the 
upper end of which is hidden by the " head " of the internal pillar ; i', hairs of internal hair cell ; e, 
external hair cell ; e', e' , e' , hairs of three external hair cells ; n, ri 1 to n*, various cross-sections of the 
spiral cord of nerve distribution ; the " tunnel cord '* extends from ri 1 to n- as a radial bundle ; t, tunnel 
space ; N, Nuel's space. (After G. Retzius. from A. Rauber's text-book, 1898, S. 818, Fig. 743.) 

The student should now make careful drawings of sections 
made in various directions through macerated temporal bones, 
labelling correctly the different structures. 



Part IV 

DISSECTION OF THE THORAX 



DISSECTION OF THE THORAX 

WALLS AND VISCEEA OF THOKAX. 

BEFOKE beginning the dissection of the thorax, the student 
should review the thorax in the articulated skeleton. Examine 

(a) Cavity of thorax (cavum thoracis). 

(b) Superior aperture of thorax (apertura thoracis superior) (0. T. 

inlet of thorax). 

(c) Inferior aperture of thorax (apertura thoracis inferior] (0. T. outlet 

or base of thorax). 

(d) Costal arches (arcus costarum}. 

(e) Intercostal spaces (spatia intercostalia) . 

(f) Infrasternal angle (angulus infrasternalis) . 

(g) Pulmonary groove (sulcus pulmonalis). 

Thoracic Walls. 

The dissector of the upper extremity and the dissector of the 
abdomen will have left certain structures still attached to the 
walls of the thorax. Of these should be noticed the Mm. pec- 
toralis major, pectoralis minor, serratus anterior, rectus abdorni- 
nis, obliquus externus abdominis, latissimus dorsi, subclavius, 
scalenus posterior ; remove all these except the M. scalenus pos- 
terior, and so expose completely the arcus costarum and the Mm. 
intercostal es. Preserve, however, the rami cutanei laterales and 
rami cutanei anteriores of the Nn. intercostales, as well as the 
perforating rami of the A. mammaria interna. 

Intercostal Muscles (Mm. intercostales). 

Clean carefully and study the form, position, origin, inser- 
tion, action, and innervation of the 

(a) External intercostal muscles (Mm. intercostales externi). 

(Observe anteriorly the external intercostal ligaments (ligamenta 
intercostalia externa) (0. T. anterior intercostal membrane).) 

(b) Internal intercostal muscles (Mm. intercostales interni). 

Bring them into view by dividing in all the spaces the Mm. 
intercostales externi and Ligg. intercostalia externa along their 
inferior margins and reflecting them upward. Avoid in.jury to the 
Aa. intercostales. Observe the internal intercostal ligaments (liga- 
menta intercostalia interna) (0. T. posterior intercostal mem- 
branes). 

399 



400 LABORATORY MANUAL OF HUMAN ANATOMY 

Intercostal Nerves (Nn. intercostales). (Vide Fig. 198.) 

The intercostal nerves should now be studied. Each nerve 
runs on the internal surface of a rib near the lower margin in 
the sulcus costae, along with the V. and A. intercostalis. The 
nerve may be brought into view by pulling downward upon the 
ramus cutaneus lateralis. Follow two or three of the nerves 
from their origin to their termination. Note that the Nn. inter- 

FIG. 198. 

Nervus spinalis (thoracalis) Rarmis cutaneus dorsalis (medialis) 

Ramus cutaneus dorsalis (lateralis) 

calis (nervus intercostalis) 
-V -,Rami musculares 



Medulla spinalis 



Radix anterior 



Ramus communicans 

Ganglion trunci sympathici iu 
cross-section 




-Ramus posterior 
of the ramus cuta- 
neus lateralis 



,Ramus cutaneus 
lateralis 



Ramus anterior of the 

ramus cutaneus 

lateralis 



<r- 

Ramus cutaneus anterior with a medial and 
a lateral branch 



The course and branching of a thoracic nerve, nervus thoradcus, in a segment of the body. 
Schematic. (After Toldt, Anat. Atlas, Wien, 1903, 3 Aufl., p. 810, Fig. 1240.) 

costales are really the anterior rami (rami anteriores) of the 
thoracic nerves (Nn. thoracales). Study the following branches : 

(a) Muscular rami (rami musculares). 

(b) Lateral cutaneous ramus (ramus cutaneus lateralis [pectoralis et 

abdominalis]). 

(c) Anterior cutaneous ramus (ramus cutaneus anterior [pectoralis et 

abdominalis]). 



DISSECTION OF THE THORAX 



401 



Intercostal Vessels. 
Study- 

(a) Highest intercostal artery (A. intercostalis suprema), from the 

truncus costocervicalis of the A. subclavia. 

(aa) Dorsal rami (rami dorsales). 

(ab) Spinal rami (rami spinales). 

(b) Intercostal arteries (Aa. intercostales) (vide Fig. 198), from the 

aorta thoracalis, and hence often called " aortic intercostal 
arteries." The posterior relations and posterior branches 
may be better studied later. 

FIG. 199. 
Muscle twig of the ramus posterior of the A. intercostalis 



Ramus cutaneus dorsalis (lateralis) 
! Ramus dorsalis of the 

anterior branch of the A. intercostalis 

M. Hiocostalis 

Muscle-layer of the trunk, for 

the upper extremity 
M. intercostalis externus 

The branch of the A. in- 
tercostalis, which runs 
along the next 
lower rib A. inter- 
costalis 
. M. subcostalis 



..M. intercostalis 
internus 



Ramus visceralis 

M. longissimus dorsi 




Mm. multifidus and semispinalis 

Rami cutanei dorsales 
(mediales) 

Ramus 

Ramus posterior of 
A. intercostalis 



Ramus dorsalis of 
the anterior branch 
of the A. intercostsilis / 
Ramus anterior of the 
A. intercostalis 

A. intercostalis 

Aorta thoracalis- 



Arteriae mediastinales anteriores 



Ramus posterior 



. Ramus anterior 



Ramus cutaneus latera- 
lis (pectoralis) 



Ramus intercostalis 
If. fr<ntr<rnii.< Dnmti'i* 
A. mammaria interna 
Ramus perforans 



Rami sternales 



The branching of the arteries of the body-wall. Schematically represented in a segment of the 
thorax. (After Toldt, Anat. Atlas, Wien, 1900, 2 AufL, p. 571, Fig. 947.) 



(ba) Posterior rami (rami posteriores) . 

(baa) Spinal ramus (ramus spinalis). 

(bab) Muscular rami (rami musculares). 

(bac) Medial cutaneous ramus (ramus cutaneus medialis). 

(bad) Lateral cutaneous ramus (ramus cutaneus lateralis). 

(bb) Anterior rami (rami anteriores). 

(bba) Muscular rami (rami musculares). 
2G 



402 LABORATORY MANUAL OF HUMAN ANATOMY 

(bbb) Lateral cutaneous rami (rami cutanei later ales [pec- 

torales et ab dominates]). 

(bbba) Posterior ramus (ramus posterior). 

(bbbb) Anterior ramus (ramus anterior). 

(bbbc) Lateral mammary rami (rami mammarii 

later ales). 

(bbc) Anterior cutaneous rami (rami cutanei anteriores 

[pectorales et ab dominates]) . 

(be) Medial mammary rami (rami mammarii mediates). 
(c) Intercostal veins (Vv. intercostales) . 

Note that they run above the arteries in the sulci costarum. 
Their posterior relations will be studied later. 

Internal Mammary Artery (A. mammaria interna). (Vide Fig. 9.) 

Remove the intercostal muscles, but work most cautiously, 
and be sure to avoid injury to the subjacent pleura, which must 
be preserved intact and left undisturbed in contact with the 
internal surface of the ribs. Clean the A. mammaria interna and 
the outer surface of the M. transversus thoracis. Observe how 
far down the pleura passes in the recess between the diaphragm 
and the costal arches. Below the pleura do not mistake the dia- 
phragm for unremoved intercostal muscles. 

Examine the following branches of the A. mammaria interna : 

(a) Sternal rami (rami sternales). 

( b ) Perforating rami ( rami perforantes ) . 

(ba) Mammary rami (rami mammarii). 

(bb) Muscular rami (rami musculares). 
(be) Cutaneous rami (rami cutanei). 

(c) Intercostal rami (rami intercostales) (0. T. anterior intercostals). 

(d) Musculophrenic artery (A. musculophrenica) . 

(e) Superior epigastric artery (A. epigastrica superior}. 

Note that (d) and (e) are terminal branches, the bifurcation 
usually occurring in the sixth intercostal space ; the sixth costal 
cartilage may be excised in order to display this better. The 
anterior mediastinal, thymic, bronchial, and pericardiacophrenic 
branches of the internal mammary artery cannot be studied until 
later. 

Transverse Muscle of Thorax (M. transversus thoracis) (O. T. Tri- 
angular is Sterni). 

Study this muscle as far as is possible at the present stage of 
the dissection. It will be better exposed later.' 



DISSECTION OF THE THORAX 



403 



THORACIC CAVITY (CAVUM THORACIS). 

It is well to precede the dissection of this region by the study 
of a frozen or formalin section l through the thorax, a little below 
its middle, in order that the general relations of the thoracic 
viscera to one another may be understood. 2 (Vide Fig. 200.) 



FIG. 200. 

Processus spinosus vertebrae thoracalis V. 

Oesophagus 

V. azygos \ 

Lymphoglandulae bronchioles \ 

Bronchus dexter 

A. pulmonalis (ramus 
dexter) 



Cavum mediastinale posterius 
Pleura mediastinalis 
Pleura costalis 
Aorta desccndens 

Bronchus sinister 
' Pulmo sinister 
/(lobus inferior) 




Pulmo dexter 

V. cava superior /' 

Auricula cordis dextrd' 

Bulbils aortae 

Cartilago costalis IL , 
Cavum mediastinale anterius 



\ \ v A. pulmonalis 

\ \ Pleura mediastinalis (pleura peri- 
* Pericardium cardiaca) 

1 "Sinus costomediastinalis 
Synchondrosis sternalis proximalis 



Horizontal section of the body between the bodies of the fifth and sixth thoracic vertebrae. (After 
Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 455, Fig. 773.) 

Pleura. 

The student has to study 

(a) Pulmonary pleura (pleura pulmonalis}. 

(b) Parietal pleura (pleura parietalis). 

Between (a) and (b) is the cavity of the pleura (cavum 
pleurae). 



1 See foot-note on making sections, p. 474. 

2 The student is strongly advised to study a series of cross-sections through 
the trunk of a human being; in this work he will find the plates and descrip- 
tions by Dr. Potter, of St. Louis, of great help; these are published under the 
title " Topographical Anatomy of the Viscera of the Thorax and Abdomen," in 
the " University Studies of the University of Missouri, 1904." 



404 LABORATORY MANUAL OF HUMAN ANATOMY 

(ba) Costal pleura (pleura costalis). 

(bb) Mediastinal pleura (pleura mediastinalis) . 
(be) Diaphragmatic pleura (pleura diaphragmatica). 

The external surface of the pleura costalis has been exposed 
already by the dissection. The loose areolar tissue between the 
pleura costalis and the Mm. intercostales interni and internal 



FIG. 201. 




Saw-cuts in sternum in Cunningham's method of opening the anterior mediastinum. 

surface of the costal arches is a part of the endothoracic fascia 
(fascia end o thoracic a) . 

The mode of reflection backward of the pleura on each side, 
from the posterior aspect of the sternum, may now be investi- 



DISSECTION OF THE THORAX 405 

gated by the method devised by Sir William Turner. (See Fig. 
201.) 

Saw through the sternum as follows : 

(1) Transversely through manubrium sterni on a line connecting the 

lower margins of the incisurae costales I., i.e., parallel to the 
lower margins of the first pair of costal cartilages. 

(2) Transversely through the lower part of the corpus sterni, midway 

between incisura costalis V. and incisura costalis VI. 

(3) Obliquely, almost vertically,, from the inferior transverse cut near 

the left margin of the sternum, upward to the middle of the supe- 
rior transverse cut. 

The saw should not be permitted to pass through the perios- 
teum on the back of the sternum ; this is to be cautiously divided 
with a scalpel. 

Gently separate the two lateral portions of the central piece 
of the sternum ; observe the parietal pleura on each side passing 
backward towards the pericardium. Insert the finger between 
the right and the left pleura, and pass it upward and downward 
through the loose areolar tissue of the anterior mediastinal cav- 
ity (cavum mediastinale anterius) (O. T. anterior mediastinum), 
between them, until the pericardium is exposed. 

Next separate the pleura costalis from the ribs, as far for- 
ward as the cartilages, by carefully passing the index-finger 
between the pleura and each rib and running it backward and 
forward ; be sure not to detach the pleura from the costal carti- 
lages. Excise, with bone-forceps, the second, third, fourth, fifth, 
and sixth ribs, cutting through them in front at their junctions 
with the costal cartilages, and behind as far back as is possible. 
Leave the sternum and costal cartilages, with adherent pleura, 
for the present, in position. 

Cut vertically through the pleura costalis, midway between 
spine and sternum, from level of costa II. to level of costa VII. 
Make two transverse incisions medialward for a distance of five 
or seven centimetres, one from each end of this vertical incision, 
and reflect the large flap of costal pleura medialward. The 
cavity of the pleura (cavum pleurae) has now been opened. 

Exploration of Pleural Cavity. 

Pass the hand into the cavum pleurae and trace the membrane 
(1) in a transversal direction, (2) in the vertical direction. Con- 
trol your exploration by a study of the figures in atlases and by 
a description in a good systematic text-book. Trace the parietal 



406 LABORATORY MANUAL OF HUMAN ANATOMY 

pleura in its costal, diaphragmatic, and mediastinal parts. 
(Vide Fig. 202.) Study- 

(a) Pulmonary ligament (ligamentum pulmonale) (triangular duplicature 

extending from hilus of lung to mediastinal pleura). 

(b) Dome or cupola of pleura (cupula pleurae}. 

Examine its relations. 

(c) Mediastinal septum (septum mediastinale) . 

(ca) Anterior mediastinal cavity (cavum mediastinale anterius). 

(cb) Posterior mediastinal cavity (cavum mediastinale posterius). 

FIG. 202. 



Pleura costalis _ . _ _ 

-Pleura pulmonalis 



LobUS SUpcnui ^^yPSMSO* , . LUIeV^a3WJM. _ Lobug superi or 



bsolute heart- 
dulness 



Lobus inferior 
Margo inferior 



Lower limit of 
pleura 



Boundaries of the lungs and pleura, from in front. Absolute heart-dulness. (After Joessel, from 
Bardeleben and Haeckel, Atlas der Topog. Anat. des Menschen, Jena, 1901, Fig. 98.) 

(d) Two parts of mediastinal pleura. 

(da) Pericardiac pleura (pleura pericardiaca) . 

(db) Mediastinal layers (laminae mediastinales) . 

(e) Sinuses of the pleura (sinus pleurae). 

(ea) Phrenicocostal sinus (sinus phrenicocostalis) . 

(eb) Costomediastinal sinus (sinus costomediastinalis) . 

(f) Adipose folds (plicae adiposae). 

(fa) Pleural villi (villi pleurales). 




DISSECTION OF THE THORAX 



407 



Look for them in the sinus phrenicocostalis and at the 
junction of the pleura mediastinalis with the pleura dia- 
phragmatica. 
(g) Differences between lines of pleural reflection on right and left sides. 

Removal of Central Portion of Sternum. 

Carefully remove the portion of the sternum between the 
superior and inferior transverse cuts, with costal cartilages at- 
tached, but save the piece for the study of the sternocostal articu- 
lations later. Separate the pleura pericardiaca (of the pleura 
mediastinalis) from the side of the pericardium. The following 
structures become visible : 

(a) Phrenic nerve (N. phrenicus). 

(b) Branches of A. mammaria interna. 

(ba) Pericardiacophrenic artery (A. pericardiacophrenica) (0. T. 

arteria comes nervi phrenici). 

(bb) Anterior mediastinal arteries (Aa. mediastinales anteriores). 
(be) Thymic arteries (Aa. thymicae). 

(bd) Bronchial rami (rami bronchioles}. 

FIG. 203. 




The lungs seen from in front, s, lobus superior ; m, lobus medius ; i, lobus inferior. (From 
Gegenbaur, Lerhb. der Anat. des Mensch., Leipzig, 1899, 7 Aufl., Bd. ii. p. Ill, Fig. 432.) 



Lungs (Pulmones). (Figs. 202 and 203.) 

The right lung (pulmo dexter] and the left lung (pulmo sin- 
ister) may next be studied. With the consent of the dissector of 
the head and neck inflate the lungs with air. Do this by inserting 
the nozzle of the bellows in the cervical portion of the trachea. 
After inflation ligate the trachea. Now study the external form 
of each lung, comparing the findings in the cadaver with atlas 
illustrations, text-book descriptions, and the His-Steger models. 
In each lung study the following: 



408 LABORATORY MANUAL OF HUMAN ANATOMY 

(a) Apex of lung (apex pulmonis). 

(b) Base of lung (basis pulmonis). 

(c) Costal surface (fades costalis) (0. T. outer surface of lung). 

(d) Mediastinal surface (fades mediastinalis) (0. T. inner surface of 

lung). 

(e) Diaphragmatic surface (fades diaphragmatica) . 

(f) Anterior border or margin (margo anterior}. 

(g) Inferior border or margin (margo inferior}, 
(h) Hilus of lung (hilus pulmonis). 

(i) Root of lung (radix pulmonis). 
(j) Cardiac impression (impressio cardiaca). 
(k) Subclavian groove (sulcus subdavius). 
(I) Interlobar incisure (indsura interlobaris) . 

The student should next pay attention to the differences 
between the right lung and the left. Which is the larger! Which 
is the shorter and wider ? Why should it be so ? 

In the right lung observe the form, position, and boun- 
daries of 

(a) Superior lobe (lobus superior). 

(b) Middle lobe (lobus medius). 

(c) Inferior lobe (lobus inferior). 

In the left lung study 

(a) Superior lobe (lobus superior). 

(b) Inferior lobe (lobus inferior). 

(c) Cardiac notch (indsura cardiaca). 

(d) Lingula of lung (lingula pulmonis). 

Root of Lung (Radix pulmonis). 

Strip the pleura off the root of the lung ; study the relations 
of neighboring structures to the root. Observe 

On both sides. 

In front of the root: 

(a) Anterior pulmonary plexus of N. vagus (plexus pulmonalis an- 

terior). 

(b) Phrenic nerve (N. phrenicus). 

(c) Pericardiacophrenic artery (A. pericardiacophrenica) . 
Behind the root : 

(a) Vagus nerve (N. vagus) (0. T. pneumogastric). 

(b) Posterior pulmonary plexus of N. vagus (plexus pulmonalis pos- 

terior) . 
Below the root : 

(a) Broad ligament of lung (ligamentum latum pulmonis). 
On right side. 

(a) Azygos vein (V. azygos} (0. T. V. azygos major). 

(b) Superior vena cava (V. cava superior). 



DISSECTION OF THE THORAX 409 

On left side. 

(a) Arch of aorta (arcus aortae). 

(b) Descending aorta (aorta descendens). 

The student should next undertake the dissection of the 
structures in the root of each lung. Isolate them in the following 
order : 

(a) Anterior pulmonary plexus (plexus pulmonalis anterior}. 

(b) Posterior pulmonary plexus (plexus pulmonalis posterior). 

To expose this, throw the lung medial ward over the pericardium 
and remove the pleura from the back part of the radix pulmonis. 
Secure the N. vagus and follow it into the plexus. 

(c) Bronchial arteries ( Aa. bronchioles), from the aorta thoracalis. 

(d) Pulmonary artery (A. pulmonalis). 

(da) Right ramus (ramus dexter). 

(db) Left ramus (ramus sinister). 

(e) Pulmonary veins (venae pulmonales). 

(ea) Right pulmonary veins (Vv. pulmonales dextrae). 

(eb) Left pulmonary veins (Vv. pulmonales sinistrae). 

(f) Bronchus, right and left (bronchus [dexter et sinister]). 

(fa) Bronchial rami (rami bronchiales) . (Vide Fig. 216.) 

(faa) Eparterial ramus (ramus bronchialis eparterialis) . 

(fab) Hyparterial rami (rami bronchiales hyparteriales). 

(g) Bronchial lymph-glands (lymphoglandulae bronchiales). 

Isolate these parts thoroughly and clean each structure; it 
may be necessary to remove the bronchial lymph-glands in order 
to expose the vessels and bronchi adequately. Fix in the memory 
the relations of bronchus, artery, and vein, from before back- 
ward and from above downward, on each side. 

Phrenic Nerve and Cardiac Plexus (N. phrenicus and plexus car- 

diacus). 

The phrenic nerve should be followed upward and downward 
on each side, and the differences in relations on the two sides 
studied. Isolate the following branches of the N. phrenicus : 

(a) Pericardiac ramus (ramus pericardiacus) . 

(b) Phrenico-abdominal rami (rami phrenicoabdominales). 

In dissecting out the cardiac plexus of nerves (plexus car- 
diacus) in the concavity of the aortic arch, follow down 

(a) Superior cardiac nerve (N. cardiacus superior), from the cervical 

sympathetic. 

(b) Inferior cardiac ramus (ramus cardiacus inferior), from the left N. 

vagus. 



410 



LABORATORY MANUAL OF HUMAN ANATOMY 



These will be found upon the arcus aortae between the N. 
vagus and the N. phrenicus. On dissection of the plexus, look 
for the cardiac ganglion of Wrisberg (ganglion cardiacum 
[Wrisbergi]). 

Pericardium. 

Clean the external surface of the pericardium thoroughly; 
observe the ligaments which connect the pericardium to the ster- 
num (ligamenta sternopericardiaca) . Examine the exact rela- 
tions of the pericardial sac to the diaphragm. Compare the 
general relations of the pericardium in the cadaver with the de- 
scription in a good text-book. 

FIG. 204. 



Pulmonary 



Lacteals 



Veins of the body 



Lymph-channel 



Pulmonary veins 




s -Arteries of the body 



Intestine 



Schematic representation of the vascular system with the lymph- and chyle- vessels. (After Gegenbaur, 
Lehrb. der Anat. des Mensch., Leipzig, 1899, 7 Aufl., Bd. ii. p. 203, Fig. 498.) 

Open the pericardium by a crucial incision, making a vertical 
cut through it from the aorta to the diaphragm and a transverse 
cut in a line from the middle of the root of one lung to that of the 
other. Examine 

(a) Parietal pericardium (pericardium). 

(b) Visceral pericardium (epicardium) . 

(c) Pericardial fluid (liquor pericardii). 

(d) Transverse sinus of pericardium (sinus transversus pericardii). 



DISSECTION OF THE THORAX 



411 



Ascertain exactly the distribution of the pericardium at the 
base of the heart and about the great vessels. 

Thymus. 

The appearances will vary according to the age of the individ- 
ual. If the cadaver be that of a child, study the following : 

(a) Right and left lobes (lobi dexter et sinister}. 

(b) Central tract (tractus centralis). 

(c) Lobules of thymus (lobuli thy mi). 



Ductusf dexter- 
Cuvieri 1 sinister .- 



V. cardinalis _ 
dextra 




FIG. 205. 



V. jugularis extern 
V. jugularis interna. 

V. subclavia 

sinistra V. subclav 
dextra 



V. anonyma sinistra 



V. cava superior '" 
Sinus coronarius cordis---'" 



V. cardinalis 
sinistra 




V. azygosj 



V. hemiazygos 



Diagrams of A, the primitive anlage of the venous system of the body and B, the formation of the 
system of the v. cava superior. (Rathke's schema with slight alterations by F. Hochstetter. ) (After 
Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 563, Fig. 939.) 



Great Veins of Thorax and their Tributaries. (Vide Fig. 205.) 

Remove the thymus or the fat-body representing it; dissect 
out the great veins of the thorax. Clean and study 

(a) Superior vena cava (V. cava superior). 

(aa) Right and left innominate veins (Vv. anonymae dextra et 
sinistra). 

(aaa) Inferior thyreoid veins (Vv. thyreoideae inferiores). 

(aab) Lowest thyreoid vein (V. thyreoideae ima). 

(aac) Thymic veins (Vv. thymicae). 

(aad) Pericardiac veins (Vv. pericardiacae) . 

(aae) Superior phrenic veins (Vv. phrenicae superiores). 

(aaf) Anterior mediastinal veins (Vv. mediastinales ante- 

rior es}. 

(aag) Anterior bronchial veins (Vv. bronchioles ante- 

rior es). 
(aah) Vertebral vein (V. vertebralis) . 

(1) Deep cervical vein (V. cervicalis profunda). 
(aai) Internal mammary vein (V. mammaria interna). 



412 



LABORATORY MANUAL OF HUMAN ANATOMY 



(1) Subcutaneous veins of abdomen (Vv. subcu- 

taneae abdominis). 

(2) Superior epigastric vein (V. epigastrica supe- 

rior), 
(aaj) Highest intercostal vein (V. intercostalis supremo} 

(0. T. left superior intercostal vein). 
(ab) Azygos vein (V. azygos} (0. T. vena azygos major). 

Its tributaries can be studied better later. 
(b) Inferior vena cava (V. cava inferior). 

FIG. 206. 



Vena cava superior 



fPulm. 
Ostium art.s 

(Aorta 

Ost. atrioventr. dextrum 




Thorax from in front with the position of the heart, d. At., right atrium ; d. V., right ventricle; 
s. V., left ventricle; A., aorta; P., A. pulmonalis; I-XII, the ribs. (From Gegenbaur, Lehrb. der 
Anat. des Mensch., Leipzig, 1899, 7 Aufl., Bd. ii. p. 221, Fig. 514.) 

Heart (Cor). (Vide Fig. 207.) 

Study thoroughly its form, position, and general relations. 
Examine the following : 

(a) Base of heart (basis cordis). 

(b) Apex of heart (apex cordis). 

(c) Right arterial orifice (ostium arteriosum dextrum) (0. T. pulmonary 

orifice). 

(d) Left arterial orifice (ostium arteriosum sinistrum) (0. T. aortic 

orifice). 

(e) Sternocostal surface (fades sternocostalis) (0. T. anterior surface). 
(/) Diaphragmatic surface (fades diaphragmatica) (0. T. posterior sur- 
face). 

(g) Surfaces of chambers of heart. 

(ga) Forechambers (atria cordis) (0. T. auricles). 

(gaa) Right atrium (atrium dextrum) (0. T. right au- 
ricle). 

(gaaa) Right auricle (auricula dextra) (0. T. 
right auricular appendix). 



DISSECTION OF THE THORAX 



413 



(gab) Left atrium (atrium sinistrum) (0. T. left auricle). 
(gaba) Left auricle (auricula sinistra) (0. T. left 

auricular appendix). 
(gb) Ventricles (ventriculi cordis). 

(gba) Right ventricle (ventriculus dexter). 

(gbb) Left ventricle (ventriculus sinister). 

(h) Coronary sulcus (sulcus coronarius) (0. T. auriculoventricular 

groove). 
(i) Anterior longitudinal sulcus (sulcus longitudinalis anterior) (0. T. 

anterior interventricular groove). 
(j) Posterior longitudinal sulcus (sulcus longitudinalis posterior) (0. T. 

posterior interventricular groove). 
(k) Notch at apex of heart (incisura [apicis] cordis). 

FIG. 207. 



Vena 
cava 
sup. 



Aorta 



Ligam. 
Botalli 




Aorta- 



Art, pulm. 
sin. 

A. pulm. Venae s .P ulm - 
Auric, sin. 




Vena cava 

sup. 
A. pulm. 

dextr. 

Venae pulm. 
dextrae 



Vena 

cava 

inf. 



Apex 

The heart : A, from in front and somewhat above and to the right ; B, from behind and somewhat 
below and to the left. X %. (From Gegenbaur, Lehrb. der Anat. des Mensch., Leipzig, 1899, 7 Aufl., 
Bd. ii. p. 208, Fig. 502.) 

Blood-vessels and Nerves of the Heart. 

In the sulci on the surface of the heart, the larger trunks of 
the blood-vessels will be found. Remove the epicardium over 
these and clean the vessels of adherent fat. The nerves are ex- 
tremely delicate and difficult to isolate. Study the arteries : 

(a) Right coronary artery of heart (A. coronaria [cordis] dextra). 

(aa) Posterior descending ramus (ramus descendens posterior). 

(b) Left coronary artery of heart (A. coronaria [cordis] sinistra). 

(ba) Circumflex ramus (ramus circumftexus) . 

(bb) Anterior descending ramus (ramus descendens anterior). 

The veins of the heart (Vv. cordis) should next be examined. 
Pull the apex forward so as to bring the diaphragmatic surface 
into view. Examine 



414 



LABORATORY MANUAL OF HUMAN ANATOMY 



(a) Coronary sinus (sinus coronarius). 

Open it with scissors throughout its entire length. 

(aa) Large vein of heart (V. cordis magna) (0. T. great cardiac 

vein). 

(ab) Posterior vein of left ventricle (V. posterior ventriculi sin- 

is tri). 

(ac) Oblique vein of left atrium (V. obliqua atrii sinistri [Mar- 

shalli]). 

Note the embryological significance of this vein. Can 
you find the ligamentum V. cavae sinistrae in the fold of 
epicardium known as the " vestigial fold of Marshall" f 

FIG. 208. 



Vena azygos 



Atrium sinistrum 



V. cava superior 
Arcus aortae 



A. pulmonalis 




Ventriculus dexter 



Incisions to open the right atrium of the heart. (After Cunningham, Man. of Pract. Anafc, Edinburgh, 
18%, 2d ed., vol. ii. p. 47, Fig. 182.) 

(ad) Middle vein of heart (V. cordis media). 

(ae) Small vein of heart (V. cordis parva). 

(b) Anterior veins of heart (Vv. cordis anteriores], to right atrium, 
brainiest veins of heart (Vv. cordis minimae) (0. T. Vv. Thebesii). 



DISSECTION OF THE THORAX 



415 



The nerves of the heart may next be studied, as far as they 
can be made out. 

(a) Anterior coronary plexus (plexus coronarius cordis anterior). 

(b) Posterior coronary plexus (plexus coronarius cordis posterior). 



Cavities of Heart. 

Pull the heart over to the left side so that the right atrium 
will be fully in view ; open the right atrium by two incisions, 



FIG. 209. 



Areas aortae 
V. cava superior 
V. azygos 




Ram us dexter of 
the A. pulmonalis 
f 



Transition of the peri- 
cardium into the epi- 
cardium on the ante- 
rior side of the Vv. 
pulmonales dextrae c" 



Tuberculum interven- 
osum (Lowed) 
Limbus fossae ov 
(Vieussenii) 
Fossa ovalis 



Transition of the peri- 
cardium into the 
epicardium on the 
V. cava inferior 

Valvula venae cavae (inferioris; 

[Eustachii] ) / 

Valvula sinus coronarii [ThebesiiY 
Foramina venarium minimarum [Tnebesii] 

Sulcus coronarius 



A. subclavia sinistra 



^--A. anonyma 



../Transition of the pericardium into 
/ the epicardium on the aorta 
and V. cava superior 

j Adipose folds of the epicardium 
/ A. pulmonalis 



. Septum atriorum 

Auricula dextra 



Conus arteriosus 



-A. coronaria 
dextra 
Cuspis anterior 

yalvulae 
tricuspidalia 

Septum 

ventricu- 

lorum 



Valvulae 

Mm. papillares 

The heart seen from the right side. After hardening in formalin in distention, the right side of 
the right atrium and ventricle were removed. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 549, 
Fig. 918.) 

(1) an almost vertical one from in front of the V. cava superior 
downward and a little backward to the V. cava inferior, and (2) 
an oblique one from the middle of the vertical incision to the tip 
of the auricula dextra cordis (0. T. right auricular appendix). 



416 LABORATORY MANUAL OF HUMAN ANATOMY 

(Vide Fig. 208.) Clean out the cavity of the right atrium with a 

wet sponge. 

Right Atrium (Atrium dextrum) (O. T. Right Auricle). 

Examine the endocardium and the myocardium of its wall, 
the openings of the V. cava superior, V. cava inferior, and sinus 
coronarius. Note the subdivision of the right atrium into two 
parts by the terminal sulcus of the right atrium (sulcus ter- 
minalis atrii dextri), which corresponds to the terminal crest 
(crista terminalis) in the interior; the posterior, medial part of 
the atrium is called the venous sinus (sinus venarum [cavarum] ) . 
Observe the exact situation of the right auricle (auricula dextra) 
(O. T. right auricular appendix). In the right atrium, examine 
also 

(a) Intervenous tubercle of Lower (tuberculum intervenosum [Loweri]). 

(b) Septum of the atria (septum atriorum) (0. T. interauricular sep- 

tum). 

(ba) Membranous part of septum of atria (pars membranacea 

septi atriorum). 

(bb) Oval fossa (fossa ovalis). 

(bba) Edge of oval fossa (limbus fossae ovalis [Vieus- 
seni]) (0. T. annulus ovalis). 

(c) Valve of inferior vena cava (valvula venae cavae [inferioris Eusta- 

chii]) (0. T. Eustachian valve). 

(d) Valve of coronary sinus (valvula sinus coronarii [Thebesii]) (0. T. 

coronary valve, or valve of Thebesius). 

(e) Venous ostium of right ventricle (ostium venosum) (0. T. right 

auriculoventricular orifice). 

(/) Foramina of the smallest veins (foramina venarum minimarum [The- 
besii]) (0. T. foramina Thebesii). 
(g) Pectinate ("comb-like") muscles (Mm. pectinati). 

Right Ventricle (Ventriculus dexter) and Pulmonary Artery (A. pul- 
monalis) . 

Cut into the right ventricle by a vertical incision half a centi- 
metre to the right of the sulcus longitudinal is anterior, extending 
all the way from the conus arteriosus to the facies diaphrag- 
matica. Make carefully a second incision from the upper end of 
the first one, transversely to the right, parallel to the sulcus 
coronarius and one centimetre below it. (Vide Fig. 210.) Avoid 
injury to the tricuspid valve ; the incision may be controlled by 
inserting the index-finger of the left hand from the right atrium 
into the ventricle through the ostium venosum. Reflect the 
V-shaped flap of the ventricular wall to the right and clean the 
cavity of the ventricle with a wet sponge. 



DISSECTION OF THE THORAX 



417 



Study the shape and general relations of the cavity and with 
the aid of Fig. 209 examine the following: 



FIG. 210. 



V. cava superior 

Line of reflection of_ 
the pericardium 



Atrium dextrum 



Sulcus coronarius 



Ventriculus dexter 




Arcus aortae 



Ligamentum arteriosum 
[Botalli] 



Auricula sinistra 



Sulcus longitudinalis 
anterior 



Ventriculus sinister 



The heart, to show lines of incisions to open the right ventricle. 



(a) Arterial cone (conus arteriosus). 

(b) Supraventrieular crest (crista supraventricularis) . 

(c) Venous orifice (ostium venosum). 

(ca) Tricuspid valve (valvula tricuspidalis) (0. T. right auriculo- 
ventricular valve). 

(caa) Anterior cusp (cuspis anterior) (0. T. infundibular 

cusp ) . 

(cab) Posterior cusp (cuspis posterior) (0. T. marginal 

cusp ) . 

(cac) Medial cusp (cuspis medialis) (0. T. septal cusp). 

(d) Papillary muscles (Mm. papillares). 

(da) Tendinous cords (chordae tendineae). 
Is there a "moderator band"? 

(e) Pulmonary artery (A. pulmonalis). 

(ea) Right ramns (ramus dexter). 

(eb) Left ramus (ramus sinister). 

(ec) Ligamentum arteriosum (ligamentum arteriosum). 

27 



418 LABORATORY MANUAL OF HUMAN ANATOMY 

What is the relation of this to the ductus arteriosus 
[Botalli] of foetal life? (Fig. 211.) 
(/) Arterial orifice of right ventricle (ostium arteriosum ventriculi dextri) 

(0. T. pulmonary orifice). 

(fa] Semilunar valves of pulmonary artery (valvulae semilunares 
A. pulmonalis). 

(faa) Anterior semilunar valve (valvula semilunaris an- 

terior}. 

(fab) Right semilunar valve (valvula semilunaris dextra). 

(fac) Left semilunar valve (valvula semilunaris sinistra). 

FIG. 211. 



Aorta descendens 
Ductus arteriosus 

A. pulmonalis 




Heart of a foetus of 7 months. {. (From Gegenbaur, Lehrb. der Anat. des Mensch., Leipzig, 
1899, 7 Aufl., Bd. ii. p. 232, Fig. 521.) 

Slit open the pulmonary artery between the anterior and 
right semilunar valves. Examine the nodules of the semilunar 
valves (noduli valvularum semilunarium) and the so-called 
" sails" of the valves (lunulae valvularum semilunarium). 

Pulmonary Veins and Left Atrium. 

The pulmonary veins (Vv. pulmonales) may again be exam- 
ined. Note the differences in the relations of the right pulmo- 
nary veins (Vv. pulmonales dextrae) and the left pulmonary 
veins (Vv. pulmonales sinistrae). 

Cut through the vena cava inferior and turn the heart 
upward. Observe the entrance of the venae pulmonales into the 
left atrium. 

The left atrium (atrium sinistrum) (0. T. left auricle) may 
next be examined. Note the size, shape, and position of its 
auricle (auricula sinistra) (0. T. left auricular appendix). 

Turn the heart well to the right, with the apex forward. 
Make an oblique cut, from the middle of the posterior margin of 
the atrium behind, forward to the tip of the auricula sinistra. 



DISSECTION OF THE THORAX 



419 



Clean the cavity. Observe the openings of the pulmonary veins 
and the opening into the left ventricle. Examine the valve of the 
oval foramen (valvula foraminis ovalis). 



FIG. 212. 



Aorta ascendens 



A. pulmonalis 



V. cava superior 

Vv. pulmonales 



Atrium sinistrum 
V. cava inferior 




Ventriculus sinister 



Incisions to open the left atrium and ventricle by Cunningham's method. (After Cunningham, 
Man. of Pract. Anat., Edinburgh, 1896, 2d ed., vol. ii. p. 58, Fig. 189.) 

Left Ventricle (Ventriculus sinister). 

Note its shape, size, and normal position. Observe that it 
forms the apex cordis. 

Stand upon the right side of the cadaver, grasp the heart 
with the left hand, the index-finger upon the upper part of the 
sulcus longitudinalis posterior, the thumb upon the upper part 
of the sulcus longitudinalis anterior. Plunge the long knife 
through the ventricle from a point below the thumb one centi- 



420 LABORATORY MANUAL OF HUMAN ANATOMY 

metre to the left of the sulcus longitudinalis anterior to a point 
below the index-finger one centimetre to the left of the sulcus 
longitudinalis posterior. Cut through to the apex, the incisions 



FIG. 213. 



Lig. arteriosum 



V. cava superior 



Aorta _. 
ascendens 



Auricula dextra ... 



Sinus transve 
pericardii 

2SB? 

naris 

posterior 

aortae 



Septum membrana- 
ceum ventriculorum 
Cuspis , 
anterior 



dalis 



Valvula , 

tricuspi- <; Cuspis - 
posterior 

Cuspis 
L medialis 




Lunula 



Apex of the 
Bifurcation of the A. pulmonalis 

^Transition of the pericardium 
.**/ into the epicardium on the 
/ ramus sinister of the A. pul- 
monalis and on the Vv. pul- 
monales sinistrae 

Sinus transversus pericardii 



A. coronaria sinistra 
^Auricula sinistra 

Valvula semi- ] 

lunaris sinistra 

Valvula [ aortae 
semilunaris 
"" posterior J 

Cuspis "1 

r anterior j va i_ 
vulae 



Mm. papil- 
lares 



Mm. papillare 
Septum musculare ventriculorum-' 



Trabeculae carneae 



The heart seen from in front. After complete hardening distended in formalin, the anterior part 
of the ventricles, of the ascending aorta, and of the pulmonary artery have been taken away by a 
frontal cut. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 552, Fig. 921.) 

running along lines parallel to the anterior and posterior sulci 
and about one centimetre distant from them. (Vide Fig. 212.) 

Clean out the blood and injection mass and examine the cavity 
and walls of the left ventricle ; compare them with those of the 
right. 



DISSECTION OF THE THORAX 421 

Observe the fleshy ridges and cords (trabeculae carneae) (0. 
T. columnae carneae), the papillary muscles (Mm. papillares), 
and tendinous cords (chordae tendineae). Here again are two 
ostia, one venous (ostium venosum) and one arterial (ostium ar- 
teriosum) ; note their relative positions. The ostium venosum 
(0. T. left auriculo ventricular opening) is guarded by the bicus- 
pid or mitral valve (valvula bicuspidalis [mitralis]). In it 
study 

(a) Anterior cusp (cuspis anterior}. 

(b) Posterior cusp (cuspis posterior). 

FIG. 214. 




Cross-section of the ventricles. (After H. v. Meyer.) a, cavity of the left ventricle; 6, cavity of 
the right ventricle. (From Gegenbaur, Lehrb. der Anat. des Mensch., Leipzig, 1899, 7 Aufl., Bd. ii. p. 
217, Fig. 511.) 

The ostium arteriosum (0. T. aortic opening) is guarded by 
the semilunar valves of the aorta (valvulae semilunares aortae), 
to be studied later. 

Septum of the Ventricles (Septum ventriculorum). 

Study its anterior and posterior insertions and examine its 
thickness in different parts. Note 

(a) Muscular septum of ventricles (septum musculare ventriculorum). 

(b) Membranous septum of ventricles (septum membranaceum ventricu- 

lorum). 

What is the embryological explanation? Make a note of the 
importance of the septum ventriculorum in connection with con- 
genital heart disease. 

Aorta and its Branches. 

Clean that part of the aorta lying within the thorax, as well 
as the structures related to it. Study the position, shape, and 
relations of the 

(a) Ascending aorta (aorta ascendens). 

(b) Arch of aorta (arcus aortae). 

(c) Thoracic portion of descending aorta (aorta descendens, pars tho- 

racalis). 



422 



LABORATORY MANUAL OF HUMAN ANATOMY 



In the ascending aorta, study from the outside 

(a) Bulb of aorta (bulbus aortae). 

.(b) Sinuses of aorta (sinus aortae [Valsalvae]) . 

(c) Coronary arteries of heart (Aa. coronariae [cordis]). 

The distribution of these arteries has already been studied. 



FIG. 215. 



A. carotia interna 



The five paired / 
branchial arte-<( 
rial arches \ 



Truncus arteriosus - 



Aorta descendens 




A. carotisr 

eommuniS' 

d extra 

A. anonyma- 

Ramus dexter 

A. pulmonalis' 

A. vertebralis. 

dextra 



A. pulmonalis ' 
Aorta ascendens 



Aa. carotides externae, dextra, 
et sinistra 



A. carotis interna 
sinistra 

Arcus aortae 

Ductus arteriosus 
Ramus sinister 
,A. pulmonalis 

A. vertebralis 
sinistra 



A. subclavia sinistra 
-- Aorta descendens 




Diagrams of the transformation in the arteries of the branchial arches : A, original, B, persistent 
disposition of the arterial stems (Rathke's schema with a slight alteration according to F. Hoch- 
stetter.) (After Toldt, Anat. Atlas, Wien, 1901, 2 Aufl., p. 563, Fig. 938.) 

In connection with the arcus aortae, studyats exact relations, 
note the isthmus aortae at its junction with the aorta descendens, 
and dissect out and study thoroughly the following great arterial 
trunks : 

(a) Innominate artery (A. anonyma}. 

(aa) Lowest thyreoid artery (A. thyreoidea ima), inconstant. 

(b) Left common carotid artery (A. carotis communis sinistra). 

(c) Left subclavian artery (A. subclavia sinistra). 

The thoracic part of the aorta descendens will be studied 
later on. 



Cardiac Plexus (Plexus cardiacus) . 

The superficial portion of this plexus has already been 
studied. Its deeper portion should next be examined. Place two 
ligatures about the arcus aortae at its junction with the aorta 
descendens and divide the aorta between them ; similarly ligate 
twice and divide between at the junction of the arcus aortae with 
the aorta descendens. Cut through the V. cava superior, just 
below the entrance into it of the V. azygos. Divide the liga- 



DISSECTION OF THE THORAX 423 

mentum arteriosum. The arcus aortae should now be drawn 
aside and the trachea and Nn. cardiac! exposed. Find the fol- 
lowing nerves, which help to form the deep cardiac plexus : 

(a) From the sympathetic system: 

(aa) Middle cardiac nerve (N. cardiacus medius). 

(ab) Inferior cardiac nerve (N. cardiacus inferior). 

(b) From the N. vagus: 

(ba) Superior cardiac rami (0. T. cervical cardiac branches of 

pneumogastric). 

Is an isolated " N. depressor" present ? 

(bb) Inferior cardiac rami from the N. recurrens (rami cardiaci 

inferior es nervi recurrentis) (0. T. cardiac branches of re- 
current laryngeal). 

Notice the subdivision of the plexus cardiacus into a right 
and a left portion. 

How is the plexus cardiacus related to the anterior and poste- 
rior coronary plexuses ? 

Removal of Heart. 

Divide the A. pulmonalis and the Vv. pulmonales and remove 
the heart from the body. Continue the incision in the anterior 
wall of the left ventricle through the ascending aorta, but make 
sure that it passes between two of the semilunar valves. 

Valves of Aorta. 

The semilunar valves of the aorta (valvulae semilunar es 
aortae) are now to be studied. 

(a) Posterior semilunar valve (valvula semilunaris posterior). 

(b) Right semilunar valve (valvula semilunaris dextra). 

(c) Left semilunar valve (valvula semilunaris sinistra). 

Examine the nodules (noduli valvularum semilunarium 
[Arantii]) (0. T. corpora Arantii) and " sails" or " lunulae" 
(lunulae valvularum semilunarium) of the valves. Examine the 
sinus aortae [Valsalvae] from the inside and note exact origin, 
on the inside, of the Aa. coronaria. 

Myocardium. 

Its relations to the epicardium and endocardium should be 
reviewed. The student should study a sheep's heart or a calf's 
heart that has been macerated in fifty per cent. HC1 or in equal 
parts of glycerin, alcohol, and nitric acid. Or a sheep's heart 
filled with a paste of flour and water may be boiled for fifteen 



LABORATORY MAXUAL OF HUMAX AXATOMY 

minutes, then placed in cold water and dissected. Other fresh 
hearts should he distended under pressure, fixed and hardened 
in fiVe or ten per cent, formalin for several days : windows may 
then he cut out in various ways in order to display internal 
Bwudiires. 

Follow the course of the muscle Bundles (a) in the atria, (b) 
in the ventricles. Study the mode of formation of the vortex of 
the heart (vortex cordis). Look up the articles by Ludwig. J. B. 
MaeCaDum. and Betzger on the distribution of the heart-mnscle 
fibres. 



.fibrous I?HI|* of Heart (Annan fibrosi). 

Cut away the atria with scissors. Examine the relative posi- 
tions of the orifices at the base of the ventricular portion of the 
heart Stud 



fbrc&ws tfarter). around 




Separate the ramus dexter from the ramus sinister of the A. 
puhnonalis and reflect each lateralward. Expose the trachea 
and bronchi thoroughly by drawing the areas aortae aside and 
ving the bronchial lymph-glands (lymphoglandulae bran- 



chides) in the angle of bifurcation of the trachea. Examine 
carefully the relations of the trachea. Xote the level of the bifur- 
cation (bifurcatio tracheae) into the right and left bronchus 
(bronchus [dexter et sinister]). Look for the broncho-oesopha- 
geal muscle (If. broneho-oesophageus). 

Posterior Mcdiastinal Cavity and its Contents. 

To open the posterior mediastinal cavity (cmum media- 
stinale posterius) (O. T. posterior mediastinum), make a vertical 
cat through the pericardium along the oesophagus and reflect the 
pericardium lateralward. Look for the pleuro-oesophageal mus- 
cle (M. pleuro-oesophageus), extending across the aorta de- 
scendens from the oesophagus to the left pleura. In the cavmn 
mediastinale posterius dissect out and study thoroughly the rela- 
tions of the following: 



DISSECTION OF THE THORAX 



425 



FK, 216. 



Z_.j ~ . " i . " - --. - 




(mb) Anterior and posterior bronchial rami ( 
(6) Anterior and posterior 



(me) Oesophageal rami (mmi 



426 



LABORATORY MANUAL OF HUMAN ANATOMY 



(aca) Anterior and posterior oesophageal plexuses (plexus 
oesophageus anterior et posterior] (0. T. plexus 
gulae). 

(b) Thoracic part of oesophagus (oesophagus, pars thoracalis). 

(c) Thoracic part of aorta descendens (aorta thoracalis}. 

Examine the aortic spindle. Study 

(ca) Visceral rami (rami viscerales). 

(caa) Bronchial arteries (Aa. bronchiales) . 

(cab) Oesophageal arteries (Aa. oesophageae). 

(cac) Pericardiac rami (rami pericardiaci) . 

(cb) Parietal rami (rami parietales). 

(cba) Mediastinal rami (rami mediastinales) . 
(ebb) Superior phrenic arteries (Aa. phrenicae supe- 
rior es). 
(cbc) Intercostal arteries (Aa. intercostales) . 

FIG. 217. 




Truncus bronchomediastinalis 



Ductus thoracicus 



.Cisterna chyli 



Truncus lumbalis 
Truncus intestinalis 

The large lymph-vessels opening into the venous system. Schematic. (After Gegenbaur, Lehrb. 
der Anat. des Mensch., Leipzig, 1899, 7 Aufl., Bd. ii. p. 339, Fig. 566.) 

(d) Thoracic duct (ductus thoracicus). (Fig. 217.) 

(e) Posterior mediastinal lymph-glands (lymphoglandulae mediastinales 
posteriores). 

Interior of the Lungs. 

Cut through the trachea three centimetres above its bifurca- 
tion. Eemove the lungs from the body. With a medium-sized 
scissors with one blunt-ended blade, cut open the bronchus and 



DISSECTION OF THE THORAX 



427 



its subdivisions, also the branches of the pulmonary artery and 
pulmonary veins in each lung. Compare the intrapulmonary 
bronchi of the two lungs. Dissect out the wall of a larger bron- 
chus; examine its muscular coat (tunica muscularis), the sub- 
mucous layer (tela submucosa), and the mucous coat (tunica 
mucosa) ; in the latter note the bronchial glands (Gl. bron- 
chiales) and the bronchial lymph-nodules (noduli lymphatici 
broncMales). How far down in a bronchus does the cartilage 
extend ? 

Study a corrosion-preparation of the bronchi and their sub- 
divisions. With the help of atlases, sections, and the model (Fig. 
218) by W. S. Miller, of the University of Wisconsin, study the 
size, shape, and relations of the following : 



3 sacculi alveolares 



FlG. 218. 
Atrium with 3 sacculi alveolares 



Sacculus alveolaris 



Atrium with the surfaces 
of attachment of 3 sacculi alveolares 



Atrium (sacculi 

alveolares cut away) 

Venula pulmonalis 



Arteriolae pulmonales 





Alveoli pulmonis 

Venula 
pulmonalis 

Atrium (with 
J s-icculi, 
1 cut away) ' 
Atrium (sacculi 
cut away 1 ) 
Venula pulmomilis 

Diu-tulu.s alveolaris 

Bronchiolus respiratorius 

Alveolar duct, with branches and blood-vessels, from the dog. (After Spalteholz, Hand Atlas 
of Human Anatomy, Leipzig, 1903, vol. iii. p. 567, Fig. 624.) 

(a) Bronchioles (bronchioli). 

(b) Respiratory bronchioles (bronchioli respirator ii). 

(c) Terminal bronchi, or alveolar ductules (ductuli alveolares). 

These open through the vestibules (iv*/ //><///) into the 

(d) Atria. 

The latter communicate through the air-sac passages with 

(e) Air-sacs (sacculi alveolares) (0. T. infundibula), which are studded 

with many 

(f) Air-cells or pulmonary alveoli (air col i pulmonis}. 



428 LABORATORY MANUAL OF HUMAN ANATOMY 

Each ductulus alveolaris with all its branches makes up a 
lobule of the lung (lobulus pulmonis). The term " lobule" as 
used by the pathologists includes several of these anatomical 
lobuli. Note the central position of the terminal branch of the 
A. pulmonis and the peripheral distribution of the roots of the 
pulmonary veins in each lobulus pulmonis. 

Thoracic Portion of Sympathetic Nervous System. 

Remove the pleura parietalis from the sides of the vertebral 
column and from the inner surface of the ribs. Dissect out the 
thoracic portion of the sympathetic nervous system (pars tho- 
racalis 8. sympathici). Study 

(a) Thoracic ganglia (ganglia thoracalia). 

How many are there? How are they located? 

(b) Great splanchnic nerve (N. splanchnicus major). 

How is it formed? Where does it leave the thorax? 
Find 
(ba) Splanchnic ganglion (ganglion splanchnicum) . 

(c) Small splanchnic nerve (N. splanchnicus minor). 

How is it formed? How does it leave the thorax? In 
the abdomen it gives off a renal ramus (ramus renalis). 

(d) Lowermost splanchnic nerve (N. splanchnicus imus). 

The plexus aorticus thoracalis, plexus cardiacus, plexus coro- 
narii, rami pulmonales, and plexus pulmonalis have been studied 
already. 

Wall of Thorax from within. 

Examine the Mm. intercostales interni and the ligamenta 
intercostalia interna from within. Clean, isolate, and study 

(a) Subcostal muscles (Mm. subcostales) . 

(b) External intercostal muscles (Mm. intercostales externi). 

These can be exposed from within by removing the ligamenta 
intercostalia interna in one or two intercostal spaces. 

(c) Intercostal arteries from the aorta (Aa. intercostales). 

The rami posteriores can now be examined at their origins. 

(d) Highest intercostal artery from the subclavian (A. intercostalis su- 

prema). 

(e) Intercostal nerves (Nn. intercostales) = anterior rami of thoracic 

nerves (rami anteriores Nn. thoracalium) . 

Examine their .proximal portions. 
(/) Intercostal veins (Vv. intercostales). 

Study carefully the differences in termination on the two sides. 
(g) Azygos vein (vena azygos) (0. T. vena azygos major). (Cf. Fig. 
205.) 



DISSECTION OF THE THORAX 429 

Study its tributaries 

(ga) Hemiazygos vein (V. hemiazygos) (0. T. V. azygos minor in- 

ferior). 

(gb) Accessory herniazygos vein (V. hemiazygos accessoria) (0. T. 

V. azygos minor superior). 

Make out the exact relations of the intercostal veins (Vv. 
intercostales) , oesophageal veins (Vv. oesophageae), and poste- 
rior bronchial veins (Vv. bronchiales posteriores) to (#), (ga), 
and (gb). What is the relation of the venous system of the ver- 
tebral column to the V. azygos 1 

Joints of the Thorax. (Vide Spalteholz, Vol. i., pp. 156-161 and 170- 

I75-) 
These are divisible into three sets 

(a) Sternocostal joints (articulationes sternocostales) . 

(b) Costovertebral joints (articulationes costovertebrales) . 

(c) Joints of vertebral column. 

These should now be dissected out. Study 

(aa) Joint-capsules (capsulae articular es} . 

(ab) Interarticular sternocostal ligament (Lig. sternocostale inter- 

articular e} (0. T. interarticular chondrosternal ligament). 

(ac) Radiate sternocostal ligaments (Ligg. sternocostalia radiata) 

(0. T. anterior and posterior chondrosternal ligaments). 

(ad) Membrane of sternum (membrana sterni). 

(ae) Costoxiphoid ligaments (Ligg. costoxiphoidea) (0. T. chon- 

droxiphoid ligaments). 

(af) Interchondral joints (articulationes interchondrales). 

(ag) Intercostal ligaments (Ligg. intercostalia) , already studied. 

In the costovertebral joints study 

(ba) Capitular joints (articulationes capitulorum) (articulations 

between the heads of the ribs and the vertebrae). 

(baa) Joint-capsules (capsulae articular 'es) . 

(bab) Radiate ligament of head of rib (Lig. capituli costae 

radiatum) (0. T. anterior costovertebral or stellate 
ligament). 

(bac) Interarticular ligament of head of rib (Lig. capituli 

costae interarticular e) . 

This is best displayed by removing the radiate 
ligament from the front of the joint. 

(bb) Costotransverse joints (articulationes costotransversariae) . 

(bba) Joint-capsules (capsulae articular e s) . 

(bbb) Ligament of tubercle of rib (Lig. tuberculi costae). 

(bbc) Ligament of neck of rib (Lig. colli costae). 

(bbd) Anterior costotransverse ligament (Lig. costotrans- 

versarium anterius). 

(bbe) Posterior costotransverse ligament (Lig. costotrans- 

versarium posterius ) . 

(bbf) Lumbocostal ligament (Lig. lumbocostale) . 



430 LABORATORY MANUAL OF HUMAN ANATOMY 

(bbg) Costotransverse foramen (foramen costotransver- 

sarium ) . 
In the vertebral column study 

(ca) Anterior longitudinal ligament (Lig. longitudinale anterius) 

(0. T. anterior common ligament). 

(cb) Posterior longitudinal ligament (Lig. longitudinale posterius) 

(0. T. posterior common ligament). 

Make vertical and transverse sections through three inter- 
vertebral disks and study 

(cc) Intervertebral fibrocartilages (fibrocartilagines interverte- 

brales). 

(cca) Fibrous ring (annulus fibrosus). 

(ccb) Pulpy nucleus (nucleus pulposus) (0. T. nucleus 

polyposus). 

The joint-capsules (capsulae articular es) and intertransverse 
ligaments (Ligg. intertransversaria) should also be examined. The 
other ligaments of the spine have been injured or removed in 
the study of the vertebral canal. 



Part V 

DISSECTION OF THE ABDOMEN AND PELVIS 



ABDOMEN AND PELVIS 

MARK out on the abdomen, perineum, and small of the back 
the various regions. Make three drawings of these regions, 
labelling them accurately, one of the anterior surface, one of the 
posterior surface, and one of the perineum when the body is in 
the lithotomy position. (Vide Figs. 1, 2, 219, and 220.) 

Inspect the surface of the abdomen. Note the lower margin 
of the thorax, counting the ribs (costae) and marking each with 
its number. Locate the heart fossa (scrobiculus cordis) and the 
navel (umbilicus). What is its position with reference to (a) 
the lumbar vertebrae, (b) the thorax and pubis? How does its 
position differ in the two sexes ! 

Observe the furrow in the median line (linea mediana ante- 
rior) and note the difference in this furrow above and below the 
umbilicus. Examine the pubic eminence (mons pubis) covered 
with hair (pubes). Note the prominences due to the Mm. recti 
abdominis and the furrows bounding these lateralward. Exam- 
ine the direction of the hair streams (flumina pilorum). Note 
the distribution of pigment in the skin; in female subjects look 
for white, depressed streaks in the skin over the side and front 
of the abdomen (striae albicantes). 

In the depression of the groin (inguen) observe the linear 
elevation due to Poupart's ligament (lig amentum inguinale 
[Pouparti]). Follow it out to the spina iliaca anterior superior. 

On the lateral surface of the abdomen define the limits of the 
loin (latus). On the posterior surface of the abdomen examine 
the small of the back (lumbus). Follow the furrow in the middle 
line (linea mediana posterior) downward to the cleft between 
the buttocks (crena ani). Note the hair streams (flumina pilo- 
rum) here and vortices pilorum. Observe the prominence on 
each side due to the M. sacrospinalis. Note that the surface of 
the lumbus passes upward over the twelfth rib into the back and 
lateralward to the loin (latus) without any perceptible delimita- 
tion; below it is separated from the surface of the hip (coxa) by 
the iliac crest. Observe the foveola coccygea. 

After thorough inspection, palpate the anterior and posterior 
surfaces. Feel the cartilage of the xiphoid process (processus 

28 433 



434 



LABORATORY MANUAL OF HUMAN ANATOMY 



xiphoideus) , the anterior ends of the seventh, eighth, ninth, 
tenth, eleventh, and twelfth ribs, the spina iliaca anterior supe- 
rior and inferior, the ranms superior oss. pubis, the symphysis 
pubis, the pubic tubercle (tuberculum pubicum), the subcuta- 
neous inguinal ring (annulus inguinalis subcutaneus] (0. T. ex- 
ternal abdominal ring), and the spermatic cord (funiculus sper- 
maticus) in the male, the round ligament in the female, the tuber 
ischiadicum and the ramus inferior ossis ischii. 

In the small of the back palpate the spinous processes, the 
crista media sacralis, the tip of the coccyx, the spina iliaca pos- 
terior superior, and the crista iliaca. 

PERINEAL REGION (REGIO PERINEALIS). 

Draw the body to the end of the table ; place a block beneath 
the buttocks and place the legs in the leg-rests. (See Fig. 221.) 
Review the surface anatomy of this region, noting the symphysis 



FIG. 219. 




The perineal region in the male. (After His, Die Anat. Nom., Leipzig, 1895, p. 104.) 

pubis, the tip of the coccyx, the tuber ischiadicum of each side, 
and the rami of the ischium and pubis. Note the subdivisions of 
this region into 



ABDOMEN AND PELVIS 435 

(1) Anal region (regie analis). 

(2) Urogenital region (regio urogenitalis) . 

(Vide Figs. 219 and 220.) 

The region anterior to the latter, comprising the external 
organs of generation, is known as the pudeudal region (regio 
pudendalis). Determine exactly the boundaries of these differ- 
ent regions. 

FIG. 220. 




The perineal region in the female. (After His, Die Anat, Nom., Leipzig, 1895, p. 105.) 

Examine the external genitalia, comparing the parts of the 
male and the female, noting differences and homologies. 



External Genital Parts in Male (Partes genitales externae). 

(a) Body of penis (corpus penis}. 

(b) Dorsum of penis (dorsum penis). 

(c) Urethral surface (fades urethralis). 

(d) Glans penis. 

(da) Corona glandis. 

(db) Septum of glans (septum glandis). 

(dc) Neck of glans (collum glandis). 

(e) Prepuce (praeputium). 

(ea) Frenulum of prepuce (frenulum praeputii}. 

(eb) Preputial glands (Gl. praeputiales) . 

(eba) Secretion (smegma praeputii). 

(f) External urethral orifice (orificium urethrae externum). 

(g) Scrotum. 

(ga) Raphe of scrotum (raphe scroti), continuous with the raplie 
penis. 



436 LABORATORY MANUAL OF HUMAN ANATOMY 

Note the amount of pigmentation about the external genitalia and its 
distribution. 

What is the perineal raphe (raphe perinei) 1 



MALE PERINEUM. 

Pass a sound into the bladder, fill the rectum with cotton or 
strips of cheese-cloth, and close the anal orifice by sutures. The 
sound should rest upon the anterior abdominal wall, and the 
scrotum may be stitched to the prepuce, thus rendering the field 
of dissection larger; Make the following incisions (Fig. 221) : 

(1) A transverse incision from the anterior extremity of the tuber ischi- 

adicum of one side to that of the other. 

(2) An incision passing in the median raphe from the scrotum in front 

to the tip of the coccyx behind. 

Reflect carefully the four flaps marked out by these incisions. 

FIG. 221. 




Skin incision, and the lithotomy position for the dissection of the perineum. At the left is shown 
a convenient iron leg-support which clamps on to the edge of the table. The table-top is covered with 
zinc. 

Superficial Perineal Fascia (Fascia superficialis perinei). (Figs. 222, 
227-229.) 

Note the general characteristics of this fascia in the regio 
analis. In the regio urogenitalis it will be found to consist of 



ABDOMEN AND PELVIS 



437 



two distinct layers. The fascia in this region is spoken of occa- 
sionally as the " inferior perineal aponeurosis." The inferior 
layer is continuous with all the neighboring superficial fascia, 
while the superior layer is dense and membranous. It is called 
Colles' fascia; it gains smooth muscular fibres anteriorly to 
form the tunica dartos of the scrotum. It is the continuation 
of Scarpa 's fascia of the abdomen into the perineum. 



...Fascia superficialis 
Testis 

-A. pudendus externus 
tH v. perinei 

A. perinei superflcialis 



Fasc. superf. perinei 

(deep layer) 
A. perinei 

~..M. trans, perinei superf. 



'-Central tendinous point 
M. levator ani 



" M. sph. ext. (anococcygeal 

layer) 
M. sph. ext. (external layer) 



Fascia superficialis perinei. ( From Poirier et Charpy, Traite d'Anat. hum., Paris, 1901 , t. ii. p. 215, 

Fig. 143.) 

To demonstrate the attachments of this deep layer proceed 
as follows: Enter the knife in the median line at the base of 
the scrotum and carry it dorsalward and lateralward to the 
tuber ischiadicum on each side, exercising caution to avoid 
injury to important vessels and nerves just below this fascia. 
Carefully dissect back the central and the two lateral flaps, 
noting the attachment of the fascia. How is it related to the 
muscles immediately beneath? 

After studying this fascia fully, proceed to the study of 
the contents of the ' ' inferior perineal compartment. ' ' 

Structures in " Inferior Compartment" of Perineum between the Fas- 
cia Superficialis Perinei and the Diaphragma Urogenitale. 

Muscles of the Perineum (Musculi perinei). (See Figs. 223 and 224.) 

These muscles are all attached to the organs of copulation and 




438 



LABORATORY MANUAL OF HUMAN ANATOMY 



they- are all derived phylogenetically from the sphincter of the 
cloaca. (Vide Holl, Die Muskelen im Beckenausgange des Men- 
schen; Merkel-Bonnet, Ergebnisse der Anatomie, xi., 1901.) 
Study the form, position, origin, insertion, action, and innerva- 
tion of each. 

(a) Superficial transverse muscle of perineum (M. transversus perinei 
superficialis) . 

In the embryo and child this muscle is well developed and con- 
stant in its relations. In the adult the muscle varies in size, 
strength, and position; in the foetus muscle bands are found 
connecting it to the M. sphincter ani externus and the M. ischio- 
cavernosus, and it may be regarded as a connecting link between 
anal musculature and the musculature of the urogenital region. 
In the adult it seems to be underging retrogressive changes. 



FIG. 223. 



lig. sacrotuberosum _ . 



M. coccygeus 



M. sphincter an 
ext. 



M. transversus perinei _ 
superficialis 




^. Lig. sacrotuberosum 



M. obturator internus 



Acetabulum 



M. ischiocavernosus 



M. bulbocavernosus 



Corpus penis 



Permeal muscles of man. On the right side the anterior part of the lig. sacrotuberosum is removed 
the M. obturator internus is divided, the M. levator ani is shown, but not labelled. (From Gegenbaur, 
Lehrb. der Anat. des Mensch., Leipzig, 1899, 7 Aufl., Bd. ii. p. 197, Fig. 496.) 

(6) Ischiocavernous muscle (M. ischiocavernosus) (0. T. erector penis 
muscle). 

According to Merkel, the tendon of this muscle fuses, as a 
rule, with the lower and lateral surfaces of the fibrous tunic of 
the corpora cavernosa. At times a tendinous slip is given off, 
which fuses with a corresponding process from the opposite side, 
on the dorsum of the penis, and thus forms a. loop about the 
dorsal vein of the penis. These processes may be muscular. If 
so, they are called the " compressor muscle of the dorsal vein of 
the penis" (M. compressor venae dor sails penis}. 



ABDOMEN AND PELVIS 



439 



(c) Bulbocavernous muscle (M. bulbocavernosus) (0. T. ejaculator 
seminis or accelerator urinae). Dissect out the following 
parts of it : 

(ca) Proper compressor of the bulb (M. compressor bulbi pro- 

prius}. 

(cb) Constrictor of root of penis (M. constrictor radicis penis). 

(cc) Compressor of the bulbar hemispheres (M. compressor 

hemisphaerium bulbi [Kobelti] ) . 

Is a M. ischiobulbosus present? Note the median tendinous 
raphe of this muscle and the relation of the muscular fibres to it. 

FIG. 224. 



Aa. scrotales posteriores 



bidbocavernosus 

ischiocavernosus 

A. penis 



A. perinei 



Diaphragma 
urogenitale 



M. traitsver- 
sus perinei 
superficialis 
A. perinei 




circumflexa 

femoris 
, medialis 
Trochanter 
major 



" '?' M. obturator internu* 
jjr \ and Mm. gemetti 

M. piriformia 
A. comitans n. ischiadici 



M. sphincter ani externus Lig sa crotuberosum 

M. glutaeus maximus 
The arteries of the male perineum. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 584, Fig. 960.) 

Arteries. (Vide Fig. 224 and Spalteholz, Fig. 473.) 

(a) Artery of perineum (A. perinei). Trace this artery forward to 

the scrotum and find 

(aa) Posterior scrotal arteries (Aa. scrotales posteriores). 
Note the course and anastomoses of the veins accompanying the 
arteries. 



440 



LABORATORY MANUAL OF HUMAN ANATOMY 



T. 



Nerves. (Fig. 225.) 

(a) Nerve of the perineum (N. perinei). 

(aa) Posterior scrotal nerves (Nn. scrotales posteriores) . 

(b) Perineal branches of posterior cutaneous nerve of thigh (0. 

branches of small sciatic). 
Lymphatics. (Vide Toldt, Fig. 1092.) 

What is the course of the lymphatics in this region? Are there 
any lymph-nodes? 

FIG. 225. 



Kami perineal. N. cutan 
femor. post. 



Nn. clunium inferiores 




N. ischiocavernosus 



Kami perineales N. 

cutan. fern. post. 
-M. transver. perinei 

superf. 
N. pudendus 

N. cut. N. fern. post. 
M. levator ani 
M. glutaeus max. 

v : ^'^LM. sphincter ani 
ext. 



Perineal nerves in the male (after Paulet). (From Poirier et Charpy, Trait< d'Anat. hum., Paris, 1899, 

t. iii, 3, p. 1154, Fig. 593.) 

Dissect away carefully the skin covering the penis, avoiding 
vessels and nerves. Observe 

(a) Root of penis (radix, penis). 

(b) Crura of penis (crura penis). 

Use models in this study. Note the divergence of the crura 
behind, also their exact relations to the ischiadic and pubic rami. 
What is their relation to the urogenital diaphragm? 

(c) Cavernous bodies of penis (corpora cavernosa penis). 

(d) Cavernous body of urethra (corpus cavernosum urethrae). 

This body may be exposed if the M. bulbocavernosus is incised 
in the median line and carefully reflected. Note how it expands 
posteriorly to form the 

(e) Bulb of urethra (bulbus urethrae). 

(ea) Hemispheres of bulb of urethra (hemisphaeria bulbi ure- 

thrae). 

(eb) Septum of bulb of urethra (septum bulbi urethrae). 



ABDOMEN AND PELVIS 



441 



Urogenital Diaphragm (Diaphragma urogenitale) and " Middle Peri- 
neal Compartment." (Figs. 226-229, 273, and 274.) 

The two dissectors should now work together. On one side 
remove the M. ischiocavernosus and detach the cms penis from 

FIG. 226. 



Urethra 



Supra-urethral layer of lig 
transversum pelvis 

V. dorsalis penis 

N. dorsalis penis 
A. dorsalis penis 



A. bulbi urethrae 
N. trans, perinei prof. 




Corp. cav. urethrae 

M. ischiocavernosus 

Cut edge of M. ischiocavernosus 



Corpus cavemosms penis 

Lig. transversum pelvis 

M. sphin. urethrae 
membranaceae 



Fasc. diap. urogen. inf. 



Inferior surface of the urogenital diaphragm, (From Poirier et Charpy, Trait< d'Anat. hum., Paris, 

1901, t. V. p. 216, Fig. 145.) 

the pubic and ischiadic rami. Turn the crus aside, avoiding 
injury to the dense fascia immediately beneath. Avoid injury 

FIG. 227. 



24, 




-Anterior layer | of the prostate-peritoneal 
Z/ Posterior layer) aponeurosis 



... '"-. Fascia diaph. urogen. sup. 

"Central tendinous point of perineum and fasc. diaph. urogen. inf. 
Fascia diaph. urogen. inf. passing beneath the bulb, ureth. 
Fascia superfic. perinei 

ig. arcual. Preprostatic layer of lig. trans, pelvis 

pubis Lig. trans, pelvis 

Supra-urethral layer of the lig. trans, pelvis 

Pelvic and permeal fasciae; sagittal section. (From Poirier et Charpy, Traite d'Anat. hum., Paris, 

1901, t. v. p. 216, Fig. 144.) 

to the pudic artery and the dorsal nerve of the penis. On the 
other side the dissection may be made without the removal of 
the muscles. Use models to complete the study. Examine the 



442 



LABORATORY MANUAL OF HUMAN ANATOMY 




urogenital diaphragm (diaphragma urogenitale) (O. T. trian- 
gular ligament). This is also known as the " middle perineal 
aponeurosis." (Vide Spalteholz, Figs. 657, 658, 673.) 

FIG. 228. 



ntoic sheath 

Fascia obturatoria 

Fasc. diaph. pelvis sup. 
Fasc. endopelvina 
Fasc. diaph. pelvis inf. 
Fasc. diaph. urogen. sup. 
Fasc. diaph. urogen. inf. 

Fascia superficialis perinei 



The perineal aponeuroses; frontal section. (From Poirier et Charpy, Traite d'Anat. hum., Paris, 1901, 

t. v. p. 217, Fig. 146.) 

Note carefully the attachments of the following layers of 
fascia and their relations to neighboring parts. 

(a) Inferior fascia of urogenital diaphragm (fascia diaphragmatis uro- 

genitalis inferior] (0. T. superficial layer of triangular ligament). 

(b) Superior fascia of urogenital diaphragm (fascia diaphragmatis uro- 

genitalis superior) (0. T. deep layer of triangular liga- 
ment). 

What is the relation posteriorly of these two layers of 
fascia to the fascia of Colles? 

The superior fascia is composed of three lamellae. In 
order from the pubic arch backward note 

(ba) Arcuate ligament of pubis (Lig. arcuatum pubis). Note the 

relation of the dorsal vein of the penis (V. dorsalis penis) 
and the dorsal nerve of the penis (N. dorsalis penis) to this 
ligament. (Vide Spalteholz, Fig. 673.) 

(bb) Transverse ligament of pelvis (Lig. transversum pelvis) (0. 

T. median puboprostatic ligament of Krause). It is a 
fibrous band extending between the ischiopubic rami imme- 
diately behind the dorsal vein of the penis and in front of 
the urethra. Note the following aponeurotic divisions. 

(1) The anterior division passes anteriorly beneath the 

dorsal vein and is attached to the fibrous tunic of 
the corpora cavernosa, forming a union between 
these two bodies. It is called the " supra-urethral 
part of the middle aponeurosis." 

(2) The posterior division passes in front of the urethra 

and the prostate, fusing with the proper capsule 
of the latter. It is known as the " preprostatic 
layer." 



ABDOMEN AND PELVIS 



443 



(fee) The third lamella covers the deep transverse muscle of the 
perineum superiorly. It extends from the urethra in the 
median line to the line extending between the tuber ischiadi- 
cum of each side posteriorly. The anterior border is inti- 
mately adherent to the urethra, while the posterior gives 
off processes which are united to the inferior aponeurosis 
of the levator ani muscle. It is also intimately adherent to 
the central tendinous point of the perineum. 



Duct. def._. 
Allantoic shea 
M. obturat. int.r_' . 
M. lev. ani 2 



FIG. 229. 

Umbilico-vesical apon. 
Fascia obturatoria 
Arcus tend. M. lev. ani 

^Fasc. M. lev. ani 
Memb. obturat. 

Apon. pubo-prost. 
.Prostate 

Inf. pelvi-rectal space 
M. trans, perinei prof. 
-Fasc. diaph. urogen. inf. 
Fasc. superflc. perinei (deep 

layer ; Colics' fascia) 
Fasc. diaph. urogen. inf. (layer 

passing under the bulb) 
Fasc. supertic. perinei 

The fasciae of the pelvic floor and of the perineum. Frontal section through the bulbus urethrae. 
(From Poirier et Charpy, Traite" d'Anat. hum., Paris, 1901, t. v., fasc. 1, p. 218, Fig. 147.) 




Kemove the inferior fascia of the urogenital diaphragm 
(fascia diaphragmatis urogenitalis inferior) on one side and 
note the contents of the " middle perineal compartment ' ' (0. T. 
space between the two layers of triangular ligament). 

Muscles. (Vide Figs. 226 and 229, and Spalteholz, Fig. 673.) 

(a) Deep transverse muscle of perineum (M. transversus perinei pro- 

fundus). What is the general direction of the fibres composing 
this muscle? What is the relation to the perineal body? (Vide 
Poirier et Charpy, t. v. p. 202.) 

(b) Sphincter muscle of the membranous urethra (M. sphincter 

urethrae membranaceae) . It is also known as the "striated 
sphincter of the urethra." Consult Poirier et Charpy, t. v. p. 
204, concerning the disposition of the fibres forming this muscle. 
Arteries. (Vide Fig. 224, and Spalteholz, Fig. 473.) 
(a) Artery of the penis (A. penis). 

(aa) Artery of bulb of urethra (A bulbi urethrae). 

(ab) Urethral artery (A. urethralis). 

(ac) Deep artery of penis (A. profunda penis). 

(ad) Dorsal artery of penis (A. dorsalis penis). 

Determine the exact relation of each artery. Dissect out the veins 
accompanying each, carefully noting relations and anastomoses. What 
is the course of the dorsal vein of the penis (V. dorsalis penis), and into 
what does it empty? 



444 LABORATORY MANUAL OF HUMAN ANATOMY 

Nerves. 

(a) Dorsal nerve of penis (N. dorsalis penis). (Vide Toldt, Fig. 1291.) 
Do any branches of this nerve pass to the muscles of the middle 
perineal compartment? 

Examine also 

(a) Bulbo-urethral glands (glandulae bulbo-urethrales [Cowperi]). 

(aa) Body of gland (corpus glandulae bulbo-urethralis) . 

(ab) Excretory duct (ductus excretorius) . 

(b) Membranous part of urethra (pars membranaceae urethrae). 

Observe that this is the most fixed portion of the urethra. 

Note that the rectum passes posteriorly and the urethra ante- 
riorly. A triangle is thus formed, the base of which is the skin. 
This is known as the " recto-urethra! triangle." 

For a description of this triangle and its contents see Poirier et 
Charpy, t. v. p. 140. 

The dissection may now be completed on the other side. 
Leave the muscles intact, preserving relations. 



UROGENITAL KEGION (EEGIO UROGENITALIS) IN 

THE FEMALE. 

Before proceeding to the dissection, review the embryology 
of the external genital parts. (Vide Kollmann, Lehrbuch der 
Entwickelungsgeschichte des Menschen, pp. 434, 435.) What 
are the genital ridge, the genital folds, the genital eminence, and 
the urogenital sinus ? Observe the following : 

External Genital Parts in Female (Partes genitales externae), (Fig. 
230.) 

(a) Pubic eminence (mons pubis). 

(b) Vulva (pudendum muliebre). 

(c) Labium majus of vulva (labium majus pudendae). 

(d) Anterior labial commissure (commissura labiorum anterior). 

(e) Posterior labial commissure (commissura labiorum posterior). 

(f) Frenulum of pudendal labia (frenulum labiorum pudendi). 

(g) Pudendal slit (rima pudendi). 

(h) Navicular fossa (fossa navicularis [vestibuli vaginae]), 
(i) Labium minus of vulva (labium minus pudendi). 
(j) Vestibule of vagina (vestibulum vaginae), 
(k) Orifice of vagina (orificium vaginae). 
(I) Clitoris (clitoris). 

(la) Body of clitoris (corpus clitoridis). 

(Ib) Glans of clitoris (glans clitoridis). 

(Ic) Prepuce of clitoris (praeputium clitoridis). 

(Id) Frenulum of clitoris (frenulum clitoridis). 



ABDOMEN AND PELVIS 445 

(m) External orifice of urethra (orificium urethrae externum). 

(n) Hymen (hymen [femininus]}. 

(o) Hymenal caruncles (carunculae hymenales). 

Notice the characteristics of the external genitalia in differ- 
ent subjects. How do the nulliparous differ from the multi- 
parous! Note the homologies existing between the female and 
the male genitals and tabulate these in your drawing-books. 



Praeputium clitoridi 

Glans clitoridis 

Frenulum clitoridis 

Labium minus pudendi 

Vestibulum vaginae-- 

Carunculae hymenales"=- 

Opening of the glandula -'? 
vestibularis major 

Fossa navicularis (vestibuli 
vaginae) 

^ 
Frenulum labiorum pudendi * 




-Commissura labiorum anterior 



^Labium ma jus pudendi 



, Ductus para-urethralis 



Orificium urethrae 
externum 

-Carina urethralis 
(vaginae) 

Columna rugarum anterior 
"Orificium vaginae 

Columna rugarum posterior 



Commissura labiorum posterior 



The female external genitalia. The labia majora have been drawn apart and the pudendal cleft 
thereby opened wide. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 498, Fig. 855.) 

Distend the rectum with cotton and close the anal and vulvar 
orifices by sutures. Make the following incisions (cf. Fig. 221) : 

(1) A transverse incision passing from the tuber ischiadicum of one side 

to that of the other. 

(2) An incision in the median line encircling the labii majora and the 

anal orifice, passing from the mons pubis in front to the tip of the 
coccyx behind. 

Reflect the four flaps. 



Superficial Perineal Fascia (Fascia perinei superficialis) and Con- 
tents of " Superficial Perineal Compartment." 

Note the general characteristics of this fascia and compare it 
with the fascia in the male. Note the two layers, superficial and 
deep. Determine the exact disposition of each. What is the 



446 



LABORATORY MANUAL OF HUMAN ANATOMY 



attachment of the deep layer? Does it acquire smooth muscle 
fibres in the labium majus to form a tunica dartos ? Study 

Arteries. 

(a) Artery of perineum (A. perinei). Trace this artery forward to 

the labia majora and dissect out 
(aa) Posterior labial arteries (Aa. labiales posteriores) . 

Look for a small artery passing into the superficial transverse 
muscle of the perineum, the " transverse perineal artery." 
Nerves. (Fig. 232.) 



FIG. 231. 



Urethra 



Vagina 



Corpus cavernosum urethrae 

Venous plexus . ^ 

"" 



Columna ant. 

....Columnapost. 



Corp. cav ----- > 
clit. 



Clitoris 




--Rectum 



Praeputium 
clitoridis 



M. sph. ext. 



Foss. navic. 



Labium minus' 

Hymen (femininus) Frenulum lab. pud. 

Sagittal section through the vulva and vagina to show the lateral walls of the vestibule. (From 
Poirier et Charpy, Traite d'Anat. hum., Paris, 1901, t. v. p. 558, Fig. 382.) 

(a) Nerve of perineum (N. perinei). 

(aa) Posterior labial nerves (Nn. labiales posteriores). 

(b) Perineal branches of posterior cutaneous nerve of thigh (0. T. 

small sciatic). 
Lymphatics. 

Determine the course of the lymphatics found in this region, 
also the lymph-nodes with which they communicate. (Vide 
Toldt, Fig. 1093.) 

Remove this fascia and expose to view the contents of the 
" superficial perineal compartment " (between fascia perinealis 
and diaphragma urogenitale). (Cf. Figs. 227, 229.) 

Clean off the fascia from the muscles, determine the form, 
position, origin, insertion, action, and nerve-supply of the fol- 
lowing : 

Muscles. (Vide Spalteholz, Fig. 669.) 

(a) Superficial transverse muscle of perineum (M. transversus perinei 
superficialis) . This muscle is not constant. It is found in the 
female in a little more than thirty per cent, of the cases. In the 
male it is more frequent. 



ABDOMEN AND PELVIS 



447 



(6) 



Bulbocavernous muscle (M. bulbocavernosus) (0. T. sphincter va- 
ginae). This muscle extends from the perineal septum behind 
to the clitoris in front. Note its homologue in the male. 

Ischiocavernous muscle (M. ischiocavernosus) (0. T. erector cli- 
toridis). 

FIG. 232. 



N. perinei 
N. cut. fern. post. 




bulbocav. 



ischiocav. 

M. trans, perinei 
superf. 

Ramus perin. N. 
cut. fern. post. 
M. levator ani 

clunium. inf. 

glut. max. 
sphincter ani ext. 



Nerves of the perineum in the female (after Paulet.) (From Poirier et Charpy, Traite d'Anat. hum., 
Paris, 1899, t. iii., 3, p. 1156, Fig. 594.) 

What is the perineal body 1 

Detach the M. bulbocavernosus and reflect it forward. The 
M. transversus perinei superficial and M. ischiocavernosus 
may also be detached. Study also 

(a) Bulb of the vestibule (bulbus vestibuli). 

The bulb will be found just beneath the M. bulbocavernosus. 
Note its relation to the labia minora and urethra. Trace these ante- 
riorly and note that the two oblong bodies forming the bulb are 
united below the clitoris by an intermediate venous plexus (pars 
intermedia of Kobelt). 

(b) Larger vestibular gland of Bartholin (glandula vestibularis major 

[Bartholini]). (Vide Spalteholz, Fig. 668.) 

Note the relation of this gland to the bulbous vestibule and 
the M. bulbocavernosus. Dissect out its excretory duct and deter- 
mine where it opens. 



448 LABORATORY MANUAL OF HUMAN ANATOMY 

Clitoris. 

The sutures inserted to close the vulvar cleft may now be 
removed. Remove the mucous membrane from the clitoris, 
leaving intact any vessels and nerves found. Study 

(a) Crura of clitoris (crura clitoridis). Determine exactly their attach- 

ments. 

(b) Body of clitoris (corpus clitoridis). 

(ba) Cavernous bodies of clitoris (corpora cavernosa clitoridis). 

(bb) Septum of cavernous bodies (septum corporum caverno- 

sorum). 
(be) Fascia of clitoris (fascia clitoridis) . 

(c) Glans of clitoris (glans clitoridis). Note that the glans is not a part 

of the corpora cavernosa, but that it is quite independent of these 
bodies. 

Urogenital Diaphragm or Trigone (Diaphragma [s. Trigonum] uro- 

genitale). 

Remove the crura clitoridis from their bony attachments, 
avoiding injury to the vessels and nerves in relation to them, 
and study the "urogenital diaphragm. " (Vide Spalteholz, Figs. 
673-675.) Make use of models to complete the study. Ex- 
amine 

(a) Inferior fascia of urogenital diaphragm 1 (fascia diaphragmatis uro- 
genitalis inferior] (0. T. anterior layer of triangular ligament). 

Cautiously remove this inferior layer of fascia and study 
the contents of the ' ' middle perineal compartment, ' ' as follows : 

Muscles. 

(a) Deep transverse muscle of perineum (M. transversus perinei pro- 

fundus). 

(b) Sphincter muscle of membranous urethra (M. sphincter urethrae 

membranaceae) . 

Arteries. (Vide Spalteholz, Fig. 474.) 
(a) Artery of clitoris (A. clitoridis). 

(aa) Artery of bulb of vestibule (A. bulbi vestibuli [vaginae]). 

(ab) Urethral artery (A. urethralis). 

(ac) Deep artery of clitoris (A. profunda clitoridis). 

(ad) Dorsal artery of clitoris (A. dorsalis clitoridis). 

Note that the two latter are given off after the A. cli- 
toridis has pierced the inferior fascia of the urogenital 
diaphragm. Find the internal pudendal veins (Vv. pu- 
dendae internae). 

1 Sometimes called the " fascia trigoni urogenitalis inferior." 



ABDOMEN AND PELVIS 449 

Nerves. 

(a) Dorsal nerve of clitoris (N. dorsalis clitoridis). 

Determine the exact course of this nerve. What relation does 
it bear to the dorsal artery of the clitoris and to the dorsal vein ? 
What relation does the latter vein bear to the ligamentum arcua- 
tum pubis and the ligamentum transversum pelvis? Demonstrate 
the presence of a part of the glandulae vestibulares majores in 
the " middle compartment of the perineum." 
Urethra. 

Note the general direction and extent of the urethra in the female. 
What is its relation to the anterior vaginal wall? (Vide Figs. 231, 291, 
and 293.) 

The superior boundary of the diaphragma urogenitale is 
formed by the superior fascia of the urogenital diaphragm 
(fascia diapliragmatis urogenitalis superior) (O. T. deep or 
posterior layer of triangular ligament). 

Note that these (the superior and inferior) layers fuse pos- 
teriorly and become continuous with the deep layer of the super- 
ficial fascia of the perineum, or " Colles' fascia." Anteriorly 
they a] so fuse to form the transverse ligament of the pelvis 
(ligamentum transversum pelvis). The dorsal vein of the cli- 
toris separates the latter from a ligament just below the pubis, 
which is known as the arcuate ligament of the pubis (ligamentum 
arcuatum pubis). 



ANAL REGION (REGIO ANALIS) AND DIAPHRAGM 

OF PELVIS (DIAPHRAGMA PELVIS) IN 

BOTH SEXES. 

Review at this stage of the dissection the general character- 
istics and disposition of the fascia in this region. After having 
reviewed this, remove it by blunt dissection. 

External Sphincter Muscle of Anus (M. sphincter ani externus). 
(Figs. 222-224, 2 3! 2 73 28 9-) 

Clean this muscle, noting carefully its form, position, origin, 
insertion, action, and innervation, and dissect out the following 
layers, proceeding from without inward : 

(a) External layer ("superficial sphincter" of Cruveilhier, the "skin 
muscle" of Luschka). It is inserted into the skin about the anus. 

(&) Anococcygeal layer, formed by the fibres arising from the coccyx 
and the ligamentum anococcygeum, encircling the anus and inserted 
29 



450 LABORATORY MANUAL OF HUMAN ANATOMY 

anteriorly into the central tendinous point of the diaphragm, be- 
coming continuous with some of the fibres of the M. bulbocaverno- 
sus. 

(c) Internal circular layer, made up of annular fibres surrounding the 
terminal part of the rectum. 

Note that the external sphincter is made up of two symmetrical 
halves. 

Clean out the fat of the ischiorectal fossa, carefully pre- 
serving the structures found therein. Proceed to the study of 
it, noting exactly the position of its boundaries. 

Ischiorectal Fossa (Fossa ischiorectalis). (Figs. 224, 232, 274, 278.) 

(a) Levator ani muscle (M. levator ani}. 

(b) Obturator internus muscle (M. obturator internus}. 

(c) Inferior fascia of pelvic diaphragm (fascia diaphragmatis pelvis in- 

ferior) (0. T. anal fascia). 

(d) Obturator fascia (fascia obturatoria) . 

At the junction of (c) and (d) as seen from below, in the angle 
between them is seen the tendinous arch of the levator ani muscle 
(arcus tendineus M. levatoris ani) (0. T. white line of pelvic 
fascia). 

(e) Posterior border of urogenital diaphragm (diaphragma urogenitale) . 

(f) Gluteus maximus muscle (M. glutaeus maximus). 

(g) Sacrotuberous ligament (ligamentum sacrotuberosum) (0. T. great 

sacrosciatic ligament). 

After having located accurately the boundaries of this fossa, 
proceed to the study of its contents : 

(a) Inferior hemorrhoidal artery (A. haemorrhoidalis inferior). (Vide 

Spalteholz, Fig. 473.) 

Determine the course of the inferior hemorrhoidal veins (Vv. 
haemorrhoidales inferiores). What is the plexus haemorrhoidalis? 
With what vessels do the above anastomose? 

(b) Inferior hemorrhoidal nerve (N. haemorrhoidalis inferior). 

(c) Anococcygeal nerves (Nn. anococcygei) (0. T. perineal branches of 

fourth sacral nerve). 

Trace the arteria haemorrhoidalis inferior back to the inter- 
nal pudendal artery (A. pudenda internet), its parent stem. 
Note that it is accompanied by the V. pudenda interna and the 
N. pudendus. These three structures run in the " canal of Al- 
cock," which is formed by the fusion of the fascia obturatoria 
with the falciform process of the ligamentum sacrotuberosum. 



ABDOMEN AND PELVIS 451 



ANTERIOR ABDOMINAL WALL. 

Inflate the abdominal cavity (cavum abdominis) by means of 
an aspirating needle and bicycle pump, and make the following 
incisions through the skin only (vide Fig. 7) : 

(1) Along the anterior median line from the level of the tip of the 

xiphoid process to the mons pubis; carry the knife around the 
umbilicus, leaving it intact. 

(2) From the upper limit of the first, transversely around the body, as 

far back as possible. 

(3) From the lower limit of the first to the tuberculum pubicum, thence 

over the ligamentum inguinale to the spina iliaca anterior superior 
and along the iliac crest as far back as possible. 

Reflect the flaps so formed, taking no fat with the skin, but 
leaving intact the layer beneath (fascia superficialis) and the 
vessels and nerves which ramify in it. 

Superficial Fascia (Fascia superficialis). 

Observe the distribution of fat, especially in the hypogastric 
region; the dense white band of tissue (linea alba) in the ante- 
rior median line; the arrangement of the superficial fascia in 
two layers, especially in the hypogastric region; superficially 
the fascia of Camper, and more deeply the fascia of Scarpa. 
Dissect out the structures in the superficial fascia, preserving 
them carefully : 

Arteries. (Vide Fig. 9.) 

(a) Superficial circumflex artery of ilium (A. circumflexa ilium super- 

ficialis) (O. T. superficial circumflex iliac artery). 

(b) Superficial epigastric artery (A. epigastrica superficialis). 

(c) External pudendal arteries (Aa. pudendae externae) (0. T. exter- 

nal pudic arteries). 
Veins. 

(a) Parumbilical vein (V. parumbilicalis) . 

(b) Thoraco-epigastric vein (V. thoraco-epigastrica) . 

(c) Superficial epigastric vein (V. epigastrica superficialis). 

(d) External pudendal veins (Vv. pudendae externae). 

(e) Superficial circumflex vein of ilium (V. circumflexa ilium super- 

ficialis ) . 
Nerves. 1 (Vide Fig. 8.) 

(a) Anterior cutaneous rami of intercostal nerves (rami cutanei ante- 
rior es). 

1 Regarding the variations in the nerves of the abdominal wall, see the 
paper by Professor Bardeen in the American Journal of Anatomy, vol. i., No. 2, 
p. 203. 



452 LABORATORY MANUAL OF HUMAN ANATOMY 

(6) Anterior cutaneous ramus of iliohypogastric nerve (ramus cutaneus 
anterior N. iliohypogastrici) (0. T. hypogastric branch). 

(c) Ilio-inguinal nerve (N. ilio-inguinalis) . 

(d) Lateral cutaneous nerves (rami cutanei later ales of Nn. inter- 

costales). 

(e) Lateral cutaneous ramus of twelfth thoracic nerve (ramus cutaneus 

lateralis N. thoracalis XII.} (0. T. iliac branch of last dorsal 
nerve). 

(/) Lateral cutaneous ramus of iliohypogastric nerve (ramus cutaneus 
lateralis N. iliohypogastrici) (0. T. iliac branch of iliohypo- 
gastric). 

Deep Fascia (Fascia profunda). 

Remove the superficial and expose the deep fascia. Compare 
the latter with the superficial. Does it contain fat! Does it 
contain blood-vessels and nerves'? 

Muscles of Abdomen (Musculi abdominis). (Cf. Fig. 6.) 

Remove the deep fascia, keeping the muscles tense and using 
a belly-bladed scalpel in the dissection of the fibres. Expose the 
underlying muscles. Make drawings of each muscle as exposed. 
Study its form, position, origin, insertion, action, and nerve- 
supply. 

(a) External oblique muscle of abdomen (M. obliquus abdominis ex- 
ternus). 

Find the lumbar triangular space (trigonum lumbale 
[Petiti]). What is the relation of the muscle to the inguinal 
ligament of Poupart (lig amentum inguinale [Pouparti])1 The 
reflection of this ligament should be carefully studied. Study 
especially Gimbernat's ligament (lig amentum lacunare [Gim- 
bernati]), the reflex ligament of Colles (tigamentum reflexum 
[Collesi]) (0. T. triangular fascia). Both these structures will 
be frequently referred to. Note the opening just lateral to the 
tuberculum pubicum, the " subcutaneous inguinal" or " exter- 
nal abdominal" ring (annulus inguinatis subcutaneus). What 
structures pass through it in the male? In the female! (See 
Spalteholz, vol. ii., Fig. 317.) 

In connection with the annulus inguinalis subcutaneus, 
study 

(aa) Superior pillar (crus superius). 

(ab) Inferior pillar (crus inferius). 

Dissect out carefully the fibres passing between the two 
crura (fibrae intercrurales) ; expose the fascia descending 



ABDOMEN AND PELVIS 



453 



upon the spermatic cord from this muscle; it is the inter- 
columnar or external spermatic fascia (fascia spermatica 
externa). 

FIG. 233. 

M. obliquus internus abdominis M. obliquus externus 
* I abdominis 



Umbilicus- 



Linea alba 



Inscriptio- 
tendinea 



Vagina M. 

reeti abdom- ^ ---.' 
inis (lamina j| 
anterior) 



Fascia trans- 

versalis ^ | \1 



1. 1(1. ilKJIli- 

nalerefl<j-niit~~ 
(Collesi) 



M. pyrami 



Annulm inguinalix 
tubcwtanev* 




y\ M. obliquus internus 

\ abdominis (laid 
V\ back) 

* Fascia transvcrsalis 



A n uliis inguinalis abdominalis 

Aponeurosis of the M. obliquus 
externus (turned over) 



\ Funiculus spermaticus 
M. interfoveolans 



M. cremaster 



The lateral part of the inguinal canal, from the abdominal Inguinal ring to the passage of the 
spermatic cord through the M. obliquus abdominis, shown 1>\ partial removal of the M. obliquus 
abdominis. The M. interfoveolaris lies on the anterior surface of the Lig. interfoveolare [Hesselbachi] . 
(After Toldt, Anat. Atlas, Wiun, 1900, 2 Ann., p. 369, Fig. 610.) 



Divide the attachment of the M. obliquus externus abdominis 
along a line one centimetre from the crista iliaca. From the 
spina iliaca anterior superior carry the incision medialward, 
then upward in the line along which the muscle-fibres pass into 
the aponeurosis. Reflect the muscle dorsalward and cranial- 



454 LABORATORY MANUAL OF HUMAN ANATOMY 

ward, noting its digitations and the muscles to which it is related. 
(Cf. Spalteholz, Fig. 317.) Examine the course of the N. ilio- 
inguinalis. 

(b) Internal oblique muscle of abdomen (M. obliquus internus ab- 

dominis). 

What is meant by the inguinal aponeurotic falx (falx aponeu- 
rotica inguinalis) (0. T. conjoined tendon)? 

O-n the right side only, divide this muscle where the fibres 
pass over into the aponeurosis and also along a line five milli- 
metres above the inguinal ligament and crista iliaca. Reflect 
the muscle dorsalward and cranialward, noting carefully the 
vessels and nerves on its deep surface. What are they? (Cf. 
Spalteholz, Figs. 319 and 324.) Note where the lateral cuta- 
neous rami of the intercostal nerves perforate this muscle. 
What is the relation of the M. cremaster to the M. obliquus in- 
ternus abdominis? 

(c) Transverse muscle of abdomen (M. transversus abdominis). 

Note carefully the relation of the falx inguinalis to the annulus 
inguinalis subcutaneus. Note where the fibres go over into the 
aponeurosis, the semilunar line (linea semilunaris [Spigeli]). 

On each side make an incision through the aponeuroses paral- 
lel to the linea alba and distant three centimetres from it, extend- 
ing throughout the entire length of the M. rectus abdominis. 
Eeflect the flaps of the aponeuroses lateralward and medialward 
respectively. Difficulty in reflecting is experienced along the 
transverse line, owing to attachment to the subjacent muscle. 
These transverse lines are the inscriptiones tendineae. How 
many of them are there? Where are they situated? What is 
their morphological significance? 

(d) Rectus ("straight") muscle of abdomen (M. rectus abdominis). 

Study its sheath (vagina recti abdominis). Note the disposition 
in its upper two-thirds and in the lower third. What theories have 
been advanced to explain this arrangement? How is the semi- 
circular line of Douglas ( linea semicircularis [Douglasi] ) formed ? 

Note the vessels and nerves which pass through the posterior 
layer of the sheath; also the artery passing from below upward 
(A. epigastrica inferior) and the one passing from above down- 
ward (A. epigastrica superior). Do these anastomose in the 
muscle ? 

(e) Pyramidal muscle (M. pyramidalis) . 

What is its relation to the M. rectus abdominis and its sheath? 
What is the phylogenetic significance of this muscle? 

This muscle is frequently absent, and also varies greatly in 
length, sometimes extending as high as the umbilicus. 



ABDOMEN AND PELVIS 



455 



White Line (Linea alba). 

What aponeuroses enter into the formation of the linea alba? 
Between what points does it extend? Note that it is broad in 
the upper two-thirds and rapidly diminishes in breadth in the 
lower third. Do you find foramina in the linea alba above the 
umbilicus ? 

Make a drawing of the dissection at this stage. 



Transversal Fascia (Fascia transversalis) (O. T. Transverse Fascia). 
On the right side cut through the M. transversus along the 
linea semilunaris and carefully reflect this muscle lateralward. 
Note under it two layers : externally, the fascia transversalis; 
internally, the peritoneum. These are separated by " extra- 
peritoneal fatty tissue. " Trace the fascia inferiorly. Note its 



FIG. 234. 



Peritonaeum parietale 



N. femoralis 
Fascia iliaca 



Plica epigastrica 




Fovea ingitinalis 
lateralis 



M. iliopsoas ' / 
Vasa sperm at ic<\ 
A, iliaca extern ' 

I', iliaca rxterna 

Plica pubovesicalis 



^ wnb&icalis 
\ media 



^ Fovea inguinalis 
media lit 

W/m niubilicalis 
laterals 



\ Farm xupravesicalis 
\ Vesica urinaria 
Plica vesicalin tranarersa 



Frontal section of the lower part of the trunk to show the lower part of the parietal peritoneum and 
its folds. Seen from behind. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 370, Fig. 611.) 

relation to the ligamentum inguinale, to the crista iliaca, and 
medial ward to the linea alba. 

On the left side, from a point immediately above the umbili- 
cus, make two incisions, one passing to the spina iliaca interior 
superior, the other to the right of the umbilicus and two centi- 
metres to the right of the linea alba, down to the ramus supe- 



456 LABORATORY MANUAL OF HUMAN ANATOMY 

rior ossis pubis. Reflect this flap laterally and downward. Note 
the fan-like attachment of the cord-like linea alba to the ossa 
pubis (this is the adminiculum lineae albae). 

Internal Surface of Anterior Abdominal Wall. (Fig. 234.) 
Note 

(a) A fibrous cord (urachus), passing from the umbilicus downward to 

the urinary bladder (vesica urinaria). 

(aa) Middle umbilical fold of peritoneum, over this (plica umbili- 
calis media). 

(b) A second cord, passing from the umbilicus to the lateral margin of 

the obliterated umbilical artery. (Spalteholz, vol. ii., Fig. 
511.) 

(ba) Lateral umbilical fold of peritoneum, over this (plica umbili- 
calis lateralis). 

(c) Band extending from linea semicircularis [Douglasi] to a point oppo- 

site the middle of the inguinal ligament. This is the A. 
epigastrica inferior and accompanying vein. 
(ca) Epigastric fold (plica epigastrica). 

(d) The three foveae thus formed: 

(da) Medial supravesical fovea (fovea supravesicalis) . By which 

plicae is this fovea limited? 

(db) Medial inguinal fovea (fovea inguinalis medialis). 

(dc) Lateral inguinal fovea (fovea inguinalis lateralis). Note 

especially its relation to the plica epigastrica. The deepest 
part of this fovea is a depression in the peritoneum indi- 
cating the position of the abdominal inguinal ring (annulus 
inguinalis abdominis) (0. T. internal abdominal ring), the 
beginning of the inguinal canal. In what structure is this 
annulus formed? 

What is Hesselbach's triangle? Note carefully its boun- 
daries. 

Inguinal Canal (Canalis inguinalis). (Vide Fig. 233.) 

Dissect the peritoneum away carefully from the anterior wall 
of the abdomen. Examine 

Posterior wall of inguinal canal. 

Note the following structures : 

(a) Thickened fold of fascia forming the lower and medial boundary 

of the annulus inguinalis abdominis (ligamentum interfoveolare) 
(0. T. Hesselbach's ligament). 

(b) Thin layer of fascia transversalis. 

(c) Interfoveolar muscle (M. inter foveolaris) (0. T. Luschka's muscle). 

(d) Medialward the inguinal aponeurotic falx (falx aponeurotica in- 

guinalis) (0. T. conjoined tendon). What muscles enter into 
the formation of it? Note carefully its insertion. Pay par- 
ticular attention to its relation to the annulus inguinalis sub- 
cutaneus. 



ABDOMEN AND PELVIS 



457 



(e) Reflex ligament of Colles (ligamentum reflexum [Collesi]) (0. T. 
triangular fascia of the abdomen). From which muscle is it 
derived ? This ligament is often referred to as the crus posterius. 
Roof of inguinal canal. 

What structures enter into its formation? 
Floor of inguinal canal. 

How is it formed? What are the contents of the canal in the male? 
In the female? (Vide Fig. 235.) 



FIG. 235. 

Funiculus spermaticus \ 




Fascia cremasterica (Cooperi) s 



Plexus pampiniformi 

Remnant of the processus vaginal! 
peritonaei 



M. cremaster- 
Tunica vaginalis communis- 

Tunica vaginalis propria 
Testis 



The spermatic cord of a boy two months old, with the coverings of the cord opened up and showing 
the remnant of the vaginal process of the peritoneum. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., 
p. 507, Fig. 878.) 

Spermatic Cord (Funiculus spermaticus). 

Each covering should be carefully dissected out and traced 
back to the muscle or fascia from which it is derived. 

(1) External spermatic fascia (fascia spermatica externa). 

(2) Cremasteric fascia (fascia cremasterica [Cooperi]). 

(3) Cremasteric muscle (M. cremaster). 

Dissect out carefully these muscular fibres and determine accu- 
rately their origin and insertion. Consult Poirier et Charpy, t. ii. 
p. 451, concerning the different views held regarding the origin 
and significance of the M. cremaster. 

What is its nerve supply and action? What part does it play 
in the Cremasteric reflex? 

(4) Vaginal process of fascia transversalis (processus vaginalis fasciae 

transversalis) (0. T. infundibuliform fascia). 

(5) What is the fate of the peritoneal process that descended into the 

scrotum (processus vaginalis peritonaei) ? What is the tunica 
vaginalis communis [testis et funiculi sperm atici] )1 



458 LABORATORY MANUAL OF HUMAN ANATOMY 

Examine the excretory duct of the testicle (ductus defer ens}. 
Note its consistence. Is it resistant to the touch? Determine its 
length. What is its course and what are its relations to the impor- 
tant structures with which it is associated? 
Arteries. 

(1) Internal spermatic artery (A. spermatica internet). 

(2) External spermatic artery (A. spermatica externa) (0. T. cremas- 

teric artery). 

(3) Deferential artery (A. deferentialis) (0. T. artery of the vas 

deferens). 

Determine from what vessel each is derived, the relation that 
they bear to each other and to the component parts of the f unicu- 
lus spermaticus. Cross-sections should be used to determine these 
relations. (See Poirier et Charpy, t. v., Fig. 236.) Do these 
arteries anastomose with one another? 
Veins. 

Observe an anterior and a posterior group. (Cf. Poirier et Charpy, 
t. v., Fig. 238.) 

What is the pampiniform plexus (plexus pampiniformis) ? What is 
the general course of the spermatic veins (Vv. spermaticae) ? Into 
what veins do they empty? Is there any difference on the right and 
left sides? 

Nerves. 

(a) External spermatic nerve (N. spermaticus externus) (0. T. genital 

branch of genito-crural). 

(b) Deferential plexus (plexus deferentialis). Note that the ilio-ingui- 

nal nerve (N. ilio-inguinalis) is found in the canal, but that it 
is not a constituent part of the spermatic cord. 

Lymphatics. 

Whence do they come and to what lymph-glands do they go? 

Round Ligament of Uterus [in Female] (Lig. teres uteri). (Vide 
Fig. 236.) 

Coverings. 

The coverings should be compared with those of the f uniculus sper- 
maticus in the male. Note differences. What is the canal of Nuck? 

Arteries. 

(a) External spermatic artery (A. spermatica externa), a branch of 

the A. epigastrica inferior. [Later the course of the A. ovarica, 
which corresponds to the arteria spermatica interna, will be 
studied.] Dissect out the terminal branches of this artery in the 
mons pubis and the labium majus. 

(b) Artery of round ligament, a small artery occasionally found within 

the cellular tissue of the round ligament, which anastomoses with 
a branch of the A. uterina. 
Veins. 

Many veins accompanying the round ligament appear mostly on the 
surface. They communicate with the uterine veins, the veins of the 
labia majora and clitoris. 



ABDOMEN AND PELVIS 



459 



Nerves. 

(a) External spermatic nerve (N. spermaticus externus), as in male. 

( b ) Sympathetic nerves from plexus uterinus. 
Lymphatics. 



FIG. 236. 



Peritoneal - 

cul-de-sac 

Ascending artery 'A\< 
of Lig. teres \^. 

M. cremaster " 




Superficial vessels of the abdominal wall 

Aponcurosis M. obi. abd. ext. 

... N. ilio-inguinalis 

.Deep epigastric vessels 
Fasc. transversalis 

A. spennat. ext. 

Lig. reflexum 

*--- [Collesi] 
4- Radicle ot V. 
spennat. ext. 



Apon. M. obi. abd. 



V. pud. ext." 



' Tuberculum pub. 
..N. ilio-inguinalis 

-Expansion of Lig. 

teres uteri 
~"-N. spennat. ext. 



The round ligament in its course through the canalis inguinalis. The ligament is drawn slightly 
downward. (In greater part after Waldeyer.) (From Poirier et Charpy, Traitt* d'Anat. hum., Paris, 
1901, t. ii. p. 436, Fig. 315.) 

Testis (Testicle). (Vide Figs. 237, 239, 240.) 

Note its position in the scrotum and the relation to it of the 
proper vaginal tunic (tunica vaginalis propria testis). Distin- 
guish a parietal layer (lamina parietalis) and a visceral layer 
(lamina visceralis). Where does the testis originate and how 
does it reach its position in the scrotum? Where may it be 
arrested in its descent and what is the resultant condition? 

Cut through the lamina parietalis along its anterior aspect. 
Examine 

(a) Superior extremity of testicle (extremitas superior). 

(b) Inferior extremity (extremitas inferior). 

(c) Lateral surface (fades lateralis). 

(d) Medial surface (fades medialis). 

(e) Anterior margin (mar go anterior). 

(f) Posterior margin (margo posterior). 



In the epididymis study 



460 



LABORATORY MANUAL OF HUMAN ANATOMY 



(a) Head (caput epididymidis) (0. T. globus major). 

(b) Body (corpus epididymidis}. 

(c) Tail (cauda epididymidis) (0. T. globus minor). 

What is the relation of the ductus deferens to the epididymis 
Dissect the testicle under water. (Vide Fig. 239.) Study 

(a) Tunica albuginea. 

(b) Mediastinum of testis (mediastinum testis [corpus Highmori]). 

(c) Septules of testicle (septula testis). 

(d) Lobules (lobuli testis). 

(e) Parenchyma (parenchyma testis). 



FIG. 237. 



Vesica urinaria 

Ampulla ductus,. 
deferentis 

Vesicula seminalis- 
Ductus deferens-- 
Ductus ejaculatorius 
Utriculus prostaticus-' 

Prostata 
Glandula bulbo-urethralis [Cowperi] 

Bulbus urethrae 




Peritonaeum 



Symphysis ossium pubis 



- Urethra 



--Corpus cavernosum 
urethrae 



Corpus cavernosum 
penis 

Appendix testis 
(Morgagnii) 



Testis 
Scrotum...) 



^~- .""' 

Diagram of the male genital organs and their relation to the urinary bladder and urethra. 
Lateral view. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 484, Fig. 816.) 

(/) Convoluted seminiferous tubules (tubuli seminiferi contorti). 
(g) Straight seminiferous tubules (tubuli seminiferi recti). 

(ga) Proper coat (tunica propria). 
(h) Network (rete testis [Halleri]). 
(i) Efferent ductules (ductuli efferentes testis). 
(j) Sperm or semen (sperma [semen]). 



In the epididymis study 



(a) Lobules (lobuli epididymidis). 

(b) Ducts (ductus epididymidis). 

(c) Aberrant ducts (ductuli aberrantes). 

(ca) Superior (ductulus aberrans superior), 



ABDOMEN AND PELVIS 



461 



FIG. 238. 



Kidney-- 



Hydatid - - 
Epididymis-- - 

Ductus deferens 



Vesicula seminalis . 
Prostata .. 

Ductus deferens 
Epididymis . 
Testis .. 




Ureter 



..Vesica urinaria 



~ Utriculus 



...Penis 



Development of the urogenital system in man. The dotted line shows the final position of the 
organs after the descent of the testicle into the scrotum. (From Poirier et Charpy, Trait6 d'Anat. hum., 
Paris 1901, t. v. p. 302, Fig. 234.) 



FIG. 239. 

Transition of the lamina parietalis tunicae vaginalis 
propriae into the lamina visceralis ' /\ 



Ductus deferens- 
Corpus epididymidis.-- 

Sinus epididymidis' 

Mediastinum testis.--' 

Septula testis---- 

Lobuli testis--- 

Tunica nlbuginea testis" 




Plexus }>ain}>'niiformi8 



-Tunica va^inalis propria (lamina 

p.'irictalis) 



Tunica vaginalia propria 

visctTiilis) 



-Tunica vaginalis communis 



Horizontal section of the right testis, epididymis, and tunica vaginalis (both the parietal and the visceral 
layer.) (After Toldt, Anat. Atlas, Wien, 1900, ~2 Aufl.. p. l>7, fig. Bfli 



462 



LABORATORY MANUAL OF HUMAN ANATOMY 



Examine also 

(a) Appendages of testis (appendices testis). 

(aa) Appendix testis [Morgagnii]) . 

(b) Paradidymis (0. T. organ of Giraldes). 



FIG. 240. 
Ductus deferens 

Ductus epididymidis 

>- :> Paradidyinis 

Ductuli efferentes 




, Mediastinum testis (corpus 
Highmori) 



Tubuli seminiferi contorti 
Tubuli seminiferi recti 
Rete testis [Halleri] 
Ductulus aberrans (inferior) Ductulus aberrans superior ( Var. ) 

The course and constituents of the canal-system of the testis and epididymis, schematically shown. 
(After Toldt, Anat. Atlas, Wien, 1900, 2 AufL, p. 487, Fig. 827.) 

Penis. 

This organ, already studied to a certain extent, should now 
be further examined. 

Dissect out the suspensory ligament (Lig. suspensorium 
penis] and the dorsal vessels and nerves. 



PERITONEUM AND VISCERA. 

Developmental Relations. (Cf. Figs. 241-244.) 

Before beginning the study of the peritoneum, the development of the 
coelomic cavities and the transitional stages in the mesenterium commune 
should be carefully studied. Frequent reference should be made to Cun- 
ningham, pp. 1054-1058; Poirier et Charpy, pp. 870-898. What are 
the foregut, midgut, hindgut, and vitelline duct, and what relation does 
this latter bear to the diverticulum occasionally found upon the ileum? 
In what percentage of the cases is this diverticulum present, and how far 
distant is it from the iliocaecal junction? 



ABDOMEN AND PELVIS 



463 



The following folds of peritoneum, connecting the intestinal tract with 
the anterior and posterior abdominal walls, should be noted (cf. Fig. 241) : 

(a) Ventral mesentery (mesenterium anterius). What is its extent? 

(b) Dorsal mesentery (mesenterium posterius). Note its extent and 

divisions. 

Note that, while these structures are found in the embryo, they 
persist in part in different forms and relations in the adult. 

(c) Duodenal loop (ansa duodenalis). 



FIG. 241. 



Ramus hepaticus 
Ramus coronarius 
A. gastrica sinistra 
A. lienalis 

A . gastro-epiploica sin. 

A. codiaca 

A. hepatica 

A. gastrica dextra 

A. gastro-epiploica dextra 

A. hepatica propria 

A. pancreaticodaod. sup. 

A. mesenterica sup. 

Aorta 

Aa. intestinales 

A. colica dextra 

A. mesenterica inferior 



Oesophagus 

Diaphragma 
Cardia 



A. haemorrhoid. sup. 
A. sacralis media 




Ventriculus 

Omentum minus 

Hepar 

Lig. falciforme hepatis 

Ant. abdom. wall 

Pylorus 

Duodenum 



Descending limb of the 
ansa umbilicalis 

Ascending limb of the ansa 

umbilicalis 
Vitelline duct 



Intestinum terminate 

Primitive mesovesica 
Pedicle of the allantois 



Cloaca and anus 



Schematic section of the abdomen of an embryo in which the segments of the alimentary canal 
have been differentiated. The section is made in the sagittal plane and is to the right of the median 
plane. The right face of the mesenterium commune dorsale and of the mesenterium ventrale is shown. 
The liver is represented isolated from the anterior abdominal wall and the diaphragm. Star with 8 
points, territory of the A. coeliaca ; star with 6 points, territory of the A. mes. sup. ; star with 4 points, 
territory of the A. mes. inf. ; 1, 2, 3, Aa. colicae dextra, media et sinistra ; g, m, d, Aa. sigmoideae ; 
cross, mesenterium ventrale. (From Fredet in Poirier et Charpy, Traits d'Anat. hum., Paris, 1901, 
2 ed., t. iv. p. 881, Fig. 455.) 



(d) Intestinal loop (ansa intestinalis or umbilicalis). The summit of 
this ansa is in communication with the vitelline duct and 
this determines its convexity anteriorly. This ansa is 
divided into two segments: 

(da) Superior descending or proximate segment, forming an 

obtuse angle with the ansa duodenalis (flexura duodeno- 
jejunalis of the embryo). 

(db) Inferior or ascending segment. This is prolonged to the 



464 



LABORATORY MANUAL OF HUMAN ANATOMY 



FIG. 242. 



Lien 

Curvatura ventriculi majoiv.^ 

Mesogastrium.,.. 

Pancreas 



Duodenum.--' 
Mesenterium commune- 
Umbilical loop of the bowel.. 




. Aorta abdominalis 

-A. gastrica sinistra 
A. lienalis 
A. coeliaca 

\--~A. hepatica 

'--Flexura duodenojejunalis 
~-A. mesenterica superior 
-Flexura coli sinistra 

A. mesenterica inferior 
Mesocolon descendens 



Analge of the intes- 

tinum caecum 

s 

Schematic representation of the form of the intestinal canal and of the mesentery in the sixth week of 
fetal life. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 435, Fig. 726.) 



FIG. 243. 



Mesogastrium (axial part) 

Curvatura ventriculi minor 
Pane 

Ductus choledoch 
Mesoduodenum- 

Flexura duodenojejunalis,' 
Mesenterium commune 




Lien 

Mesogastrium (peripheral part) 

Curvatura ventriculi major 
Flexura coli sinistra 



Mesocolon descendens 



9 

The form of the human alimentary intestinal canal and mesentery in the eighth week of fetal life. 
Schematic. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 435, Fig. 727. "> 



ABDOMEN AND PELVIS 



465 



(dc) 



following segment, forming an 
colico-lienalis of the embryo). 
Derivatives. 



acute angle (flexura 



(1) From the descending segment: intestinum tenue. 

(2) From the ascending segment: 

a) Terminal part of the intestinum tenue. 

b) Caecum. 

c) Colon ascendens. 

d) Colon transversum. 

The remainder of the primitive intestinal tube, from the flexura colico- 
lienalis on, is called the intestinum terminate. What are the derivatives 
of this? Special attention should be paid to the vascular relation of the 
different segments. 

FIG. 244. 



Aorta - 



Corpus ventriculi 



Mesoduodenum 



Mesocolon ascendens 



Intestinum caecum I- 




_ Flexura coli sinistra 

Mesocolon transversum 
Flexura duodenojejunalis 

Mesocolon descendens 
Mesenterium 

Mesocolon sigmoideum 



The form of the human intestinal canal and mesentery in the middle of the fourth month of foetal 
life. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 435, Fig. 728. ) 

Make a drawing showing the viscera in position, and name 
each viscus visible. Make a preliminary survey of the organs 
in the abdominal cavity, examining exact position and general 
characters of the stomach (ventriculus) , small intestine (intes- 
tinum tenue), large intestine (intestinum crassum), rectum (in- 
testinum rectum), pancreas (pancreas), liver (hepar), and 
spleen (lien). 

Note that the peritoneum (tunica serosa) lines the walls of 

30 



466 



LABORATORY MANUAL OF HUMAN ANATOMY 



FIG. 245, 



Vena anonyma sinistra 

Thymus 
Cavum mediastinale anterius 

Corpu 
Pericardium 

Cavum pericardii_ 



Hepar 

Ventriculus- 
Bursa omentalis- 
Mesocolon transversum^- 
Colon transversum 



Omen- ( Lamina anterior 
turn -J 
majus (Lamina posterior 

Mesenterium 
Intestinum ileum - 

Intestinum tenue 



Spatium praeperitonaeale - 
[Retzii] 

Vesica urinaria -- 
Symphysis ossium pubis 



Tunica vaginalis propria 

Testis - 




- Vertebra thoracalis I. 
LVTrachea 

-\ Oesophagus 

- A. pulmonalis dextra 

- Cavum pericardii 
~ Pericardium 

- Cavum mediastinale posterius 
- Diaphragma 

Omentum minus 

Pancreas 
- Spatium retroperitonaeale 

Duodenum (pars horizontals) 

,-.-. Cavum peritonaei 

patium retroperitonaeale 
..Promontorium 

-Intestinum rectum 



\Excavatio rectovesicalis 
Anus 



Schematic representation of the course and arrangement of the peritoneum, mesentery, and omental 
bursa in normal condition. The blue line indicates the primary parietal peritoneum ; the red line, the 
mesogastrium ; and the yellow line, the visceral peritoneum and peritoneal covering of the mesentery. 
The continuous lines show the free surface of the peritoneum ; the dotted lines show those parts of the 
peritoneum of which the free surfaces have been lost by fusion. (After Toldt, Anat. Atlas, Wien, 1900, 
2 Aufl., p. 440, Fig. 737.) 



ABDOMEN AND PELVIS 



467 



the abdominal cavity as the parietal peritoneum (peritonaeum 
parietale) and covers the viscera as the visceral peritoneum 
(peritonaeum viscerale). The space between these two layers, 
which exists only upon dissection, is the peritoneal cavity 
(cavum peritonaei). In the male this is completely closed, but 
in the female it communicates with the exterior through the 
abdominal openings of the Fallopian tubes. 



Great Omentum (Omentum majus). (Figs. 245, 258.) 

What is its position and form and of what tissue is it com- 
posed ? 

What is its relation to that part of the large intestine passing 
transversely across the abdomen (colon transversum) 1 Is its 
relation in the adult the same as in the embryo? How is it re- 

FIG. 246. 

V. enva inf. Aorta Retropancreatic " fascia of fusion " 

Ren (dexter) ^^rowr^L ^fe^Ss^ Ren (sinister) 



Paries abdom- 
inis 



Hepar 



Ductus 
choledochus 



V. portae 
A. hepat. prop. 

A. hepatica 




Lig. gastro- 

lienale 

Lig. phrenico 
henale 



Ventricnlna 



Lig. teres hepatis 

Omentum minus 
Lig. falciforme Ix-p.-ttis 



Cavum peritonaei 



Corpus pancreatis 
Vestibulum bursae omentalis 



Transverse section passing through the bursa omentalis at the level of the foramen epiploicum, that 
is, in-low the hepatocaval meso. Surface below the plane of section. Schematic. Thearro\v indicates 
the opening between the V. cava inferior behind and the V. portae, ductus choledochus, and A. hepatica 
propria in front. The great extent of the bursa omentalis is due to its lodging, at this level, the pro- 
jecting lobus caudatus [Spigelii]. (From Fredet in Poirier et Charpy, Traite d'Anat. hum., Paris, 1900, 
2 ed., t. iv. p. 1011, Fig. 576.) 

lated to the stomach? How many layers of peritoneum form it? 
Does it enclose any cavity! 

Trace the anterior two layers to the lower margin of the 
stomach. These two layers separate to enclose the stomach, 



468 LABORATORY MANUAL OF HUMAN ANATOMY 

meeting at its superior border. The double layer of peritoneum 
thus formed, passing between the stomach and the transverse 
fissure of the liver, is called the lesser or gastrohepatic omentum 
(omentum minus). 

Lesser Omentum (Omentum minus). (Figs. 241, 245, 246.) 

Examine the thickened right border, the hepatoduodenal liga- 
ment (ligamentum hepatoduodenale) ; the remaining portion is 
sometimes referred to as the hepatogastric ligament (ligamen- 
tum hepatogastricum). 

How many layers of peritoneum help to form this lesser 
omentum! What relation do these layers bear to the different 
peritoneal cavities! From which primitive mesentery is the 
omentum minus derived! 

Mesentery (Mesenterium). (Fig. 252.) 

What is the length of attachment to the posterior abdominal 
wall ! This attachment is called the root of the mesentery ( radix 
mesenterii). What is the length of the attachment to the bowel! 
What is the greatest length between its two attachments ! 

Note carefully between which vertebrae the mesentery ex- 
tends; also its general direction. It divides the abdominal 
cavity (cavum abdominis) into an upper right and a lower left 
compartment. (Cf. Waldeyer's Kolon nischen.) 

Determine the relation of the radix mesenterii to the pancreas 
and to the terminal portion of the duodenum. (Vide Poirier et 
Charpy, t. iv., Fig. 494; Spalteholz, Fig. 563.) 

Mesocolon (Mesocolon). 

(a) Ascending mesocolon (mesocolon ascendens). It is found in only 
twenty-six per cent, of the cases in the adult. (Treves.) How do 
you explain its absence in the remaining seventy-four per cent., 
while it is constantly present in the embryo? For a discussion 
concerning the factors leading up to the disappearance of these 
different peritoneal folds and the fixation of organs previously 
mobile, see Poirier et Charpy, 2 ed., t. iv., Fig. 498. What 
is Toldt's theory? What are the "fasciae of fusion"? Read 
about the relation of this fascia to the head of the pancreas, 
the right kidney, and the right ureter. What is the fascia of 
Treitz? From what is it derived and what relation does it bear 
to the head of the pancreas ? 

(fc) Transverse mesocolon (mesocolon transfer sum}. Note the general 
direction of this mesocolon. How many layers of peritoneum form 
this fold, and to which peritoneal sac does each belong? Is the 
arrangement in the adult the same as in the embryo? Determine 



ABDOMEN AND PELVIS 469 

its relation to the duodenum, the head of the pancreas, and the 
duodenojejunal angle. What is the length of this mesocolon? 
Does it readily permit of displacement of the colon ? Note that the 
peritoneal relations of the first part of the transverse mesocolon 
depend somewhat upon the position and size of the liver. (Vide 
Cunningham, p. 1033.) 

(c) Descending mesocolon (mesocolon descendens). The descending colon 

is fixed in eighty-five per cent, of the cases ( Jonnesco and Charpy) ; 
in sixty-four per cent. (Treves). The disappearance of the primi- 
tive mesocolon descendens is accounted for by Toldt's theory. De- 
termine the relation of the fascia remaining to the left kidney and 
ureter. Determine with accuracy the relation of the left kidney 
to the descending colon. Do you find any paracolic fossae (recessus 
paracolici) ? 

(d) Sigmoid mesocolon (mesocolon sigmoideum). Note its general direc- 

tions and relations. (Vide Cunningham, p. 1035.) The length of 
this mesocolon bears a relation to the frequent torsion of the bowel 
(volvulus) occurring here. Does the length of this part of the in- 
testine differ in carnivora, herbivora, and omnivora? Where does 
the mesocolon sigmoideum end? 

Mesorectum. 

Where does the mesorectum begin? How is it related to the 
sacral vertebrae ? How far is it attached to the rectum ? 

After having made a careful study of these different perito- 
neal folds, the student should turn the omentum and transverse 
colon up on to the thoracic wall and proceed to the study of 

Peritoneal Fossae about the Duodenojejunal Angle. (Vide Fig. 247 ; 
Cunningham, p. 1018; Poirier et Charpy, t. iv. pp. 265-267.) 

(a) Inferior duodenal fossa (fossa duodenalis inferior). How frequently 

is this fossa present ? Determine its relation to the terminal portion 
of the duodenum and to the vertebrae. Is this fossa vascular? 
What is the inferior duodenal plica (plica duodenalis inferior) ? 
Determine depth and width of this fossa, comparing it with fossae 
found in other subjects. 

(b) Superior duodenal fossa (fossa duodenalis superior). This fossa is 

found in about fifty per cent, of the cases, occurring less constantly 
than the preceding. What relation does it bear, if present, to the 
second lumbar vertebra and the body of the pancreas? What is 
the superior duodenal plica (plica duodenalis superior) ? Is this 
fossa vascular? If so, determine what vessels course in the plica. 
The two fossae frequently occur together. If both are present in 
your subject, compare as to depth, width, vascular relations, etc. 

(c) Duodenojejunal fossa (fossa duodenojejunalis of Jonnesco). This 

fossa occurs in about twenty per cent, of the cases and is never 
coincident with the other fossae found at this flexura. Determine 
the relation that this fossa bears to the aorta, ihe left kidney, and 
the left renal vein. What are the plica duodenojejunalis dextra 
and sinistra? 



470 



LABORATORY MANUAL OF HUMAN ANATOMY 



(d) Paraduodenal fossa (fossa paraduodenalis) (fossa of Landzert). 

This fossa is rarely found in the adult, occurring in a little less 
than three per cent, of the cases. It is more frequently found in the 
new-born. It is situated some distance to the left of the terminal 
portion of the duodenum. If present, note especially its relation 
to the inferior mesenteric vein and the ascending branch of the left 
colic artery. The peritoneal folds raised by these vessels produce 
the fossa. What is the plica mesentericomesocolica ? 



Intestinum jejunum 



FlG. 247. 

Mesocolon transversum 




V. xnesenterica inf. 



Plica duodenalis sup. 



Fossa duodenal is sup. 



Fossa duodenalis inf. 

Plica duodenalis inf. 

__ ^^^^ __ . colica sinistra 

Mesenterium 

Pars ascendens duodeni 

Fossae duodenales superior et inferior (after Jonnesco). (From Poirier et Charpy, Traite d'Anat. 
hum., Paris, 1901, 2 ed., t. iv. p. 907, Fig. 483.) 

(e) Retroduodenal fossa (fossa retro duodenalis] . 

Infrequent in occurrence. Upon what does the formation of 
this fossa depend? In this connection reference should again be 
made to the fascia of Treitz. 

Many anatomists recognize the existence of but one fossa at this 
angle. It is called the duodenojejunal fossa of Treitz. The stu- 
dent should refer to Poirier et Charpy, t. iv. p. 269. 

Peritoneal Plicae and Fossae about the Caecum. 

Before proceeding to a study of these plicae and fossae, some 
idea should be had concerning the disposition of the folds of 
peritoneum forming the mesentery at the iliocaecal junction. 
Arriving at this junction, the right leaf of the mesentery passes 
from the anterior surface of the ileum upon the caecum, and 
the left leaf takes a similar course posteriorly. They then rejoin 
upon the external border and inferior extremity of the caecum 
and the base of the appendix. In passing from the ileum to the 
caecum and appendix, the folds of the mesentery meet the short 



ABDOMEN AND PELVIS 471 

anterior caecal and the appendicular and recurring iliac arteries, 
and also a band of muscle passing from the base of the appendix 
to the ileum. There are thus formed three 

Folds (plicae). 

(a) Mesentericocaecal fold (plica mesentericocaecalis), which con- 

tains the short anterior caecal artery. 

(b) Meso-appendix (mesentericum processus vermiformis), in which 

the appendicular artery runs. 

(c) Ileocaecal or ileo-appendicular fold (plica ileocaecalis or plica ileo- 

appendicularis) , containing the muscular band passing from the 
base of the appendix to the ileum and the recurring ileal branch 
of the appendicular artery. This plica is often spoken of as the 
" bloodless fold of Treves." 
These three plicae form two fossae. 

Fossae. (See Cunningham, pp. 1030, 1031; Poirier et Charpy, pp. 338- 
340.) 

(a) Superior ileocaecal recess (recessus ileocaecalis superior), situated 

behind the plica mesentericocaecalis. This fossa and fold corre- 
spond to the ileocolic of Cunningham. It. is well developed in 
the new-born, but is less distinct in the adult. Increase in the 
diameters of the caecum and deposition of fat within the plica 
account for the diminution in size. 

(b) Inferior ileocaecal recess or ileo-appendicular fossa (recessus ileo- 

caecalis inferior). This is the ileocaecal fossa of Cunningham. 
If the appendix is drawn downward and the finger passed along 
the lower border of the terminal part of the ileum towards the 
caecum, it will generally enter a fossa situated in the angle 
between the ileum and the caecum. The fold bounding this fossa 
in front is the " bloodless fold of Treves," or plica ileocaecalis ; 
that behind, the meso-appendix, or mesenteriolum processus ver- 
miformis. 

Turn the caecum and adjacent parts of the ileum upward and 
expose the following : 

Folds (plicae). 

(a) Parietocaecal fold (plica parietocaecalis) , extending from the iliac 

fossa or lumbar region to the external wall of the caecum or 
colon ascendens. Note the general shape and attachments of this 
fold. Does it contain vessels? Between what vessels do they 
establish an anastomosis? (Vide Poirier et Charpy, t. iv., 340.) 

(b) Mesentericoparietal fold (plica mesentericoparietalis) . This fold 

represents not only the attachment of the mesentery to the iliac 
fossa, but also its prolongation below along the posterior abdomi- 
nal wall into the pelvic cavity. Is this fold ever prolonged as 
far downward as the openings of the femoral and inguinal 
canals? 
Fossae or recesses. 

(a) Retrocaecal fossa (recessus retrocaecalis) . 

Determine accurately the boundaries, depth, breadth, etc., of 



472 LABORATORY MANUAL OF HUMAN ANATOMY 

this recess. It frequently lodges the appendix, a condition which 
is said to favor the development of appendicitis. 

(b) Iliaco-subfascial fossa (fossa iliaco-subfascialis [Biesiadecki]) . 

This is a depression or pouch lined by peritoneum in the mid- 
dle of the iliac fossa. 

(c) Paracolic recess (recessus paracolici). 

(d) Intersigmoid recess (recessus intersigmoideus) . 

Raise the sigmoid colon and its peritoneal fold upward and a 
small opening will be found, corresponding to the apex of the 
V-shaped attachment of its root to the posterior abdominal wall. 

This fossa is due to the imperfect fusion of the mesentery of 
the descending colon of the foetus with the parietal peritoneum. 
(See Cunningham, p. 1036; Poirier et Charpy, t. iv., Fig. 191.) 

(e) Phrenicohepatic recesses (recessus phrenicohepatici) . 

Omental Bursa, or Lesser Peritoneal Cavity (Bursa omentalis). 
(Fig. 246.) 

Pass the finger beneath the right free border of the omentum 
minus, through the opening there into the omental bursa. 

Examine 

(a) Vestibule of bursa (vestibulum bursae omentalis). 

(b) Extension upward behind liver, superior omental recess (recessus 

superior omentalis) , downward behind the stomach, inferior omen- 
tal recess (recessus inferior omentalis), to the left as far as the 
spleen, splenic recess (recessus lienalis). 

(c) Gastropancreatic fold (plica gastropancreatica) . 

What is the method of formation of this pouch in the embryo? 
(Vide Cunningham, p. 1073; Poirier et Charpy, t. iv., Figs. 517- 
520.) 

Epiploic Foramen (Foramen epiploicum [Winslowi]) (O. T. Fora- 
men of Winslow). (Fig. 246.) 

How is it formed? Examine its boundaries : Anteriorly, the 
Lig. hepatoduodenale. Feel it. Special attention should be paid 
to this ligament, because of the important vessels and ducts con- 
tained in it. Superiorly, the liver. What part of the liver 
forms this boundary! Posteriorly, the posterior abdominal wall 
and inferior vena cava. Inferiorly, a fold of peritoneum, cover- 
ing the hepatic artery as it passes upward to reach the ligamen- 
tum hepatoduodenale. The dissection of this ligament will be 
made later. 

Peritoneal Ligaments. 

Locate accurately the following peritoneal folds : 

(1) Phrenicocolic ligament (Lig. phrenicocolicum) (0. T. costocolic liga- 
ment). From what is it developed? (Vide Cunningham, p. 1033.) 



ABDOMEN AND PELVIS 473 

What is its relation to the spleen? (Vide Spalteholz, Figs. 592, 
593.) Why has it been called the sustentaculum lienis? 

(2) Phrenicosplenic ligament (Lig. phrenicolienale) . Is it present? 

(3) Ligaments of liver. 

(a) Coronary ligament of liver (Lig. coronarium hepatis). (Vide 

Cunningham, p. 1066.) 

(b) Falciform ligament of liver (Lig. falciforme hepatis). 

(c) Right and left triangular ligaments (Lig. triangulare dextrum 

et sinistrum). 

(4) Ligaments of omentum minus. 

(a) Hepatoduodenal ligament (Lig. hepatoduodenale) . 

(b) Hepatogastric ligament (Lig. hepatogastricum). 

(5) Hepatorenal ligament (Lig. hepatorenale). (Cf. Spalteholz, Fig. 

594.) 

(6) Duodenorenal ligament (Lig. duodenorenale) . (Cf. Spalteholz, Fig. 

595.) 

(7) Gastrolienal ligament (Lig. gastrolienale) (0. T. gastrosplenic omen- 

turn). 

(8) Gastrocolic ligament (Lig. gastrocolicum) . 

In the pelvic cavity study the general disposition of the peri- 
toneum. To what extent does it cover the rectum, uterus, and 
bladder ? 

Note especially the following: 

In the male. 

(a) Anterior surface of the bladder. Is it covered by peritoneum? 

What is the prevesical space of Retzius (cavum Retzii) ? (Vide 
Cunningham, p. 410.) 

(b) Pouch between bladder and rectum. This is known as the exca- 

vatio rectovesicalis. 

(c) Pubovesical fold (plica pubovesicalis) , also the transverse vesical 

fold (plica vesicalis transversa). 

In the female. 

(a) Broad ligament of uterus (Lig. latum uteri). What are the meso- 

metrium, the mesovarium, and the mesosalpinx ? (Vide Figs. 
290 and 293; Spalteholz, Fig. 662; Toldt, Fig. 845.) 

(b) Ovarian bursa (bursa ovarica). 

(c) Suspensory ligament of ovary (Lig. suspensorium ovarii) (Toldt, 

Fig. 900). Why is this fold often referred to as the infundibulo- 
pelvic ligament? What artery runs in this fold? 

(d) Recto-uterine fold (plica recto-uterina). 

(e) Recto-uterine excavation, or cul-de-sac of Douglas (excavatio recto- 

uterina [Douglasi] ) . 

What viscera are said to be retroperitoneal ? Determine 
what viscera have a complete peritoneal covering. What vis- 
cera are only partially covered by this membrane? 

How can you expose the third portion of the duodenum (pars 
inferior duodeni) f What is its relation to the parietal perito- 



474 LABORATORY MANUAL OF HUMAN "ANATOMY 

neum! Demonstrate three methods by which the pancreas can 
be exposed anteriorly. 

How can the kidney be reached from the anterior abdominal 
wall ? What structures may be taken as guides to it ? Note espe- 
cially the relation of the kidneys to the ascending colon and de- 
scending colon, duodenum, and liver. 

Locate accurately the position of the appendix. Do the longi- 
tudinal bands passing out on to the caecum ever serve as a guide ! 
What are these longitudinal bands called ? The tip of the appen- 
dix is found sometimes directly beneath the liver. How do you 
explain this 1 

After having gained an accurate knowledge of these different 
folds, fossae, etc., the student should trace the peritoneum longi- 
tudinally and transversely, demonstrating that the layers form- 
ing the greater and lesser sacs are continuous. Transverse 
tracings should be made (a) at the level of the foramen epiploi- 
cum [Winslowi] and (b) at a level below the transverse colon. 
(See Figs. 245 and 246.) Use transverse sections of a body 
hardened in formalin in this study. 1 

Superior Mesenteric Artery (A. mesenterica superior) and its 
Branches. (Fig. 248.) 

Turn the great omentum and transverse colon upward upon 
the thorax. Remove the anterior leaf of the mesentery by blunt 
dissection from the flexura duodenojejunalis downward as far 
as the terminal portion of the ileum; remove the peritoneum 
passing from the posterior abdominal wall upon the intestinum 
caecum and colon ascendens and also the inferior layer of the 
mesocolon transversum. 

Study the following branches of the superior mesenteric 
artery. (Vide Fig. 248, and Spalteholz, Fig. 466.) 

(a) Inferior pancreaticoduodenal artery (A. pancreaticoduodenalis in- 

ferior). 

(b) Intestinal arteries (Aa. intestinales) . 

(ba) Jejunal arteries (Aa. jejunales). 

(bb) Heal arteries (Aa. ileae) (0. T. rami intestini tennis). 

(c) Ileocolie artery (A. ileocolica). 

(ca) Appendicular artery (A. appendicularis) . 

(d) Right colic artery (A. colica dextra). 

(e) Middle colic artery (A. colica media). 

1 See foot-note, p. 403. For a method of making cross-sections consult Pro- 
fessor C. M. Jackson's paper in the Jour. Am. Med. Assoc. 



ABDOMEN AND PELVIS 



475 



Determine the number of arcades formed by the superior 
mesenteric artery before the ultimate intestinal branches are 
given off. Do these ultimate arteries anastomose with each 
other I What are ' ' terminal arteries ' ' ! 

The blood supply of the caecum and appendix is derived 
from the arteria ileocolica. It runs in the terminal part of the 



FIG. 248. 



A. pancreatico 
duodenalis 

inferior 
A. colica medic 



A. colica dextra 



A. iliocolica 




Processus vermiformis 



The superior mesenteric artery. The small intestine has been laid over to the left and the trans- 
verse colon turned upward. (After Gegenbaur, Lehrb. der Anat. des Mcnsch., Leipzig, 1899, 7 Aufl., 
Bd. ii. p. 277, Fig. MO.) 

mesentery and, as it approaches the ileocaecal junction, gives 
off four small twigs. Two of these supply the anterior and pos- 
terior surfaces of the caecum and are known respectively as the 
anterior and the posterior caecal artery. The anterior caecal 
artery gives rise to a fold in the peritoneum, which we already 
know as the plica mesentericocaecalis. The artery to the appen- 
dix is directed below and to the left, passing behind the terminal 
portion of the ileum to enter the mesenteriolum processus venni- 



476 LABORATORY MANUAL OF HUMAN ANATOMY 

formis. It may pass in front of the ileum, then giving a special 
form and disposition to the meso-appendix. The fourth branch 
passes to the left along the ileum. 

The following arteries may occasionally be derived from the 
superior mesenteric : 

(1) Hepatic artery (A. hepatica), or right branch of the proper hepatic 

(ramus dexter arteriae hepaticae propriae). The importance of 
the anomalous origin of these arteries will be discussed when the 
dissection of the hepatoduodenal ligament is made. 

(2) Cystic artery (A. cystica). 

(3) Coronary left gastric artery, or artery of stomach (A. gastrica 

sinistra). 

(4) Left colic artery (A. colica sinistra). 

(5) Superior hemorrhoidal (A. haemorrhoidalis superior). 

What relation does the superior mesenteric artery bear to 
the omphalomesenteric artery in the embryo? Does MeckePs 
diverticulum, when present, receive any branches from this 
artery ? 

Superior Mesenteric Vein (V. mesenterica superior) and its Tribu- 
taries. (Vide Spalteholz, Fig. 497.) 

This vein accompanies the artery. Follow its course until it 
joins the splenic vein (V. splenica). 

The following tributaries may be found : 

(a) Intestinal veins (Vv. intestinales) . 

(b) Right gastro-epiploic vein (V. gastro-epiploica dextra). 

(c) Pancreatic veins (Vv. pancreaticae) . 

(d) Ileocolic vein (V. ileocolica). 

(e) Right colic veins (Vv. colicae dextrae). 

(f) Middle colic vein (V. colica media). 

(g) Pancreaticoduodenal veins (Vv. pancreaticoduodenales) . 
(h) Duodenal veins (Vv. duodenales). 

Where the intestine is applied directly to the posterior abdominal wall 
without the interposition of peritoneum, an anastomosis is established 
between the systemic and portal circulations. These anastomoses have 
been well established in pathological cases. What do you understand by 
the veins of Retzius ? 

Superior Mesenteric Plexus (Plexus mesentericus superior). (Vide 
Toldt, Fig. 1332.) 

A dense plexus of sympathetic nerves surrounds the superior 
mesenteric artery, and filaments from it accompany the different 
branches of the artery to the gut. Dissect out carefully these 
filaments and determine whether they join in the spaces between 



ABDOMEN AND PELVIS 



477 



FIG. 249. 



V. jugularis interna - 



haticus 



Truncus 



subclavius dexter^ 



exter 

V. subclavia dextra 

V. anonyma dextra 



Ductus thoracicus 
V. jugularis interna 

' Truncus jugularis sinister 
' Truncus subclavius sinister 

V. subclavia sinistra 



V. azygos- 



Lymphoglandulae .- 
intercostales ' 



Lymphoglandulae 
axillares and plexus 
-7 (lymphaticus) axillaris 



Aorta descendens 



Ductus thoracicus 



V. hemiazygos 



Crus mediate of the pars_ 
lumbali* diaphragmatis 

Trunci lumbales, dexter 
and sinister 

Plexus (lymphaticus) 
lumbalis 



Lymphoglandulae 
aorticae and plexus 
(lymphaticus) 
uorticus 



Lymphoglandu- 
lae sac rales 
and plexus __J 
sacral is 
medius 
Fascia iliopectinea 



EtoKnmftiler'fl 

lymph-node and 
the deep plexus 
inguinalis 



Iirol'iindac and 

vasa lymphatica 

profunda 

A. and V. 

femoral is 




Cisterna chyli 
Truncus intestinalis 



Lymphoglandulae 
lumbales 

Lymphoglandulae 
iliacae and plexus 
Y' iliacus externus 



Lig. 

(Poupartii 

Lyinphoglandu- 
lae inguinalcs 
sujx-rlicial 
plexus iu- 
guinalis 



Marffofatctfonnis 

< i-iini a inf> I'inf I 

Lymphogundtuse 



upernciale 

V. sajilifiia magna 



The thoracic duct and its tributaries. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 700, Fig. 1082.) 



478 LABORATORY MANUAL OF HUMAN ANATOMY 

the arteries. From what larger sympathetic plexus are the 
nerves of this plexus derived? 

Mesenteric Lymph-glands (Lymphoglaiidulae mesentericae). (Vide 

Fig. 249, and Toldt, Fig. 1083.) 

How large are these glands? Where are they most numer- 
ous ? Do you find any along the intestinal margin of the mesen- 
tery? Examine the lymph-nodes in the mesocolon (lymplio- 
glandulae mesocolicae). What is the course and destination of 
the lacteals ? 

Inferior Mesenteric Vessels and Nerves. 

Turn the loops of the small intestine to the right side of the 
body cavity. Remove by blunt dissection the peritoneum of the 
posterior abdominal wall and that passing from the posterior 
abdominal wall upon the colon descendens and colon sigmoideum. 
Study- 

(a) Inferior mesenteric artery (A. mesenterica inferior). (Vide Fig. 

250, and Spalteholz, Fig. 465.) 

(da) Left colic artery (A. colica sinistra). Determine with what 
vessels this artery anastomoses above and below. Does it 
form arcades before the intestinal branches are given off? 

(ab) Sigmoid arteries (Aa. sigmoideae} . 

(ac) Superior hemorrhoidal artery (A. haemorrhoidalis superior). 

This artery descends into the pelvis between the layers 
of the pelvic mesocolon, and is found upon the posterior 
surface of the rectum. Its distribution will be studied in 
a later dissection. When it reaches the rectal ampulla it 
divides into two branches which descend upon the sides of 
the rectum as far as the anus. 

(b) Inferior mesenteric vein (V. mesenterica inferior). (Vide Spalte- 

holz, Fig. 497.) 

The beginning of this vein will be found later when the 
dissection of the rectal wall is made. Two large lateral 
tributaries will be found which run upon each side of the 
rectum. They unite to form the 

(ba) Superior hemorrhoidal vein (V. haemorrhoidalis superior). 

An anastomosis is established in the rectal wall between the 
systemic and portal circulation. Hemorrhoids often de- 
velop as a result of disease of the liver or occlusion of the 
portal vein. Why? 

(bb) Sigmoid veins (Vv. sigmoideae). 
(be) Left colic vein (V. colica sinistra). 

What relation does the V. mesenterica inferior bear to 
the artery? Into what large vein does it empty above? 
Use models to study the relation of this vein to the pancreas 
and the surrounding viscera. 



ABDOMEN AND PELVIS 



479 



Inferior mesenteric plexus (plexus mesentericus inferior). 

Dissect out carefully the filaments of the sympathetic nerves sur- 
rounding the branches of the artery and trace them to the intes- 
tinal wall. What relation do they bear to the aortic plexus (plexus 
aorticus abdominalis) f Study the latter now also. 

FIG. 250. 




A. colica media 

A. mcsenterica 
superior 



A. mesenterica 
inferior 



A. colica sinistra 
Ramus descendens 



A. haemorrhoidalis 
superior 



The inferior mesenteric artery. The small intestine has been laid over to the right. The transverse 
colon has been turned upward and the sigmoid flexure spread out. (After Gegenbaur, Lehrb. der Anat. 
des Mensch., Leipzig, 1899, 7 AufL, Bd. ii. p. 279, Fig. 542.) 

(d) Left mesocolic lymphatics. 

Do you find any lymph-nodes? What is the course and destina- 
tion of the lymphatics draining the colon descendens and colon 
sigmoideuni ? 

Mesenterial Small Intestine (Intestinum tenue mesenteriale). 

That portion of the small intestine which in the adult is at- 
tached to the posterior abdominal wall by a mesentery is known 
as the intestinum tenue mesenteriale. (Vide Figs. 251-3 and 
Spalteholz, Figs. 565, 566, 568, 569.) 

It is arbitrarily divided into an upper one-third (two-fifths, 



480 LABORATORY MANUAL OF HUMAN ANATOMY 

Winslow; three-fifths, Hyrtl, Merkel), which is known as the 
empty intestine, or jejunum (intestinum jejunum), and a lower 
two-thirds, known as the twisted intestine, or ileum (intestinum 

FIG. 251. 




Usual position of the intestines in the abdominal cavity. Although this is an actual specimen it 
represent! the condition in twenty-one of forty-one cadavers. The numbers in the figure mark the 
parts which are homologous with the loops correspondingly numbered in Figs. 252 and 253 ( ifter 
Mall, Devel. of the Hum. Int. and its Position in the Adult, Bull. J. H. Hosp Baltimore 1898 vol ix 
Nos. 90 and 91, Plate iv., Fig. 16.) 

ileum). The duodenum in the adult has no mesentery, and ac- 
cordingly does not belong to the " mesenterial small intestine. " 



ABDOMEN AND PELVIS 



481 



Use models for the study of the position and relations. The 
viscera soon lose their characteristic shapes and relations in 
the cadaver, unless they have been hardened in situ by the injec- 
tion of some hardening fluid, such as formalin. 

Are the loops of the intestinum tenue mesenteriale arranged 



FIG. 252. 



1,2 




Usual position of the mesentery. Cf. Fig. 251. (After Mall, ibid., Plate v., Fig. 17.) 

in any definite order? Can you find in the model a superior 
group directly underneath the colon and passing transversely 
across the abdominal cavity, two vertical groups situated on 
either side of the vertebral column, and an inferior group within 
the small pelvis and passing transversely across it? Note that 

31 



482 



LABORATORY MANUAL OF HUMAN ANATOMY 



the convolutions placed between the preceding four groups have 
no definite orientation. 1 

Forty-one per cent, of the total length of the intestinum tenue 
mesenteriale is situated in the abdomen to the left of the median 



FIG. 253. 




Course of the intestine. This figure is taken from a model made from the same cadaver from which 
Figs. 251 and 252 were drawn. (After Mall, ibid., Plate v., Fig. 18.) 

sagittal plane, eighteen per cent, to the right of it, and forty-one 
per cent, within the pelvis. 

1 For a full discussion concerning the arrangement of the intestinal loops, 
consult Mall, F. P., The Development of the Human Intestine, Bulletin of Johns 
Hopkins Hospital, 1898; Archiv f. Anat., 1897; Sernoff, Zur Kenntniss d. 
Diinndarms, Intern. Monatschr. f. Anat., 1894. 



ABDOMEN AND PELVIS 483 

The loops of the jejunum will be found in the superior half 
of the regio mesogastrica and on each side of the vertebral 
column ; the convolutions of the ileum are situated in the lower 
half of the same region, in the regio hypogastrica, and in the 
pelvis. The convolutions occupying the space between the two 
psoas muscles are the most mobile. They are the most frequent 
content in inguinal and femoral herniae. Determine the rela- 
tions of the small intestine to the colon transversum and its 
mesocolon above ; to the intestinum caecum and colon ascendens 
on the right and colon descendens and colon sigmoideum on the 
left; to the annulus inguinalis abdominalis and annulus femor- 
alis below and lateralward, and to the urinary bladder, uterus, 
and rectum in the median plane of the body. 

What factors are concerned in maintaining the loops of the 
small intestine in their normal position ? What is enteroptosis ? 

Removal of the Intestines. 

Apply two ligatures around the upper end of the jejunum 
about two inches below the flexura duodenojejunalis. Cut 
between these. Cut through the blood-vessels and the remaining 
fold of peritoneum of the mesentery along the line of their at- 
tachment to the intestinal wall as far down as four inches above 
the ileocaecal junction. Apply two more ligatures there and cut 
between them. The intestine should now be taken to the sink, 
the ligatures removed, and all contents of the bowel thoroughly 
washed away. 

Remove a small piece of equal length from each end of the 
intestine and weigh. Which is the heavier? Which has the 
thicker walls? Feel them between the fingers. To what is the 
greater thickness of the one due? Which is the more vascular? 
Which has the larger lumen, the jejunum or the ileum? 

Remove about six inches from the upper part of the jejunum, 
open it along its mesenteric border, and thoroughly clean the 
mucous membrane. Spread it out carefully and pin it down 
upon a cork dissecting tray, with the serous surface upward, and 
study its coats. 

Coats of Small Intestine. 

(a) Serous coat (tunica serosa). 

(b) Muscular coat (tunica muscularis). 

(ba) Longitudinal layer (stratum longitudinale) . 

(bb) Circular layer (stratum circular e}. 

(c) Submucous coat (tela submucosa). 



484 LABORATORY MANUAL OF HUMAN ANATOMY 

(d) Mucous coat (tunica mucosa). This will be studied in continuity. 
Can you make out the lamina muscularis mucosae? 

Open the remainder of the small intestine along its mesen- 
teric border, using an enterotome, and proceed to the study of 
the 

(a) Circular folds (plicae circulares [Kerkringi]) (0. T. valvulae con- 
niventes). (Fig. 254.) What happens to these folds when the in- 
testinal wall is put upon the stretch 1 ? How far above the ileocaecal 
valve (valvula coli) do they disappear? These folds are occasion- 
ally found extending as far as the ileocaecal junction in diseases 
such as tuberculosis of the peritoneum, where the total length of 
the small intestine is shortened. Cruveilhier and Kazzander have 

FIG. 254. 

Tunica serosa -m 

-^^^n 

Plicae circulares [Kerkringi] 

Tunica mucosa v ^ ^ - 5 S1 '' 

\ 




A piece of the intestinum jejunum in part cut open. (After Toldt, Anat. Atlas, Wien, 1900, 

2 Aufl., p. 426, Fig. 698.) 

seen them extending thus far in cadavers in which no disease of the 
peritoneum or intestine could be detected. Three forms are to 
be found, according to Kazzander. Most of the folds extend only 
part way about the wall of the gut; others surround the wall com- 
pletely; while the third set has a spiral arrangement. Can you 
find one of each variety? They number 678 in the male and 644 
in the female (Kazzander). What coats of the intestine enter into 
the formation of these folds'? What effect does this arrange- 
ment have? How do you explain their formation? Folds which 
are parallel to the long axis of the bowel are occasionally found. 
Upon what factors does their formation depend? Do you find any 
in your subject? 
(6) Intestinal villi (villi intestinales) . Wash the mucous membrane clean 



ABDOMEN AND PELVIS 



485 



and examine it with a pocket lens. About twelve villi are found 
to the square millimetre (Sappey). Their total number is about 
ten millions. Where are they most numerous? 

(c) Intestinal glands (Gl. intestinales [Lieberkuehni]) (0. T. crypts of 

Lieberkuehn). Look for their orifices with a lens. 

(d) Solitary lymph-nodules (noduli lymphatici solitarii). They are en- 

larged in many of the acute infectious diseases so as to be easily 
visible. 

(e) Aggregated lymph-nodules of Peyer, or Peyer' s patches (noduli lym- 

phatici aggregati [Peyeri]). These should be studied carefully 
and a correct idea of normal appearance be gained. They are the 
seat of pathological changes in typhoid fever and often also in 
tuberculosis. Notice that they are situated opposite the mesenteric 
attachment. They are most easily found if the bowel is held to the 
light. They number from thirty-five to forty (Sappey; fifteen 
to fifty, Frey). What is their general form 1 ? Measure an elliptical 
patch and note in drawing-book the measurements. What is the 
general appearance of a patch? How is its long axis directed? 
(Vide Fig. 255.) 

FIG. 255. 




Noduli lymphatici aggregati ( Peyeri) Noduli lymphatici solitarii 

Noduli lymphatici aggregati [Peyeri], " Peyer' s patch " of the intestinum ileum. Natural size. 
(After Toldt, Anat. Atlas, Wicn, 1900, 2 Aufl., p. 426, Fig. 701.) 

Tabulate in your note-book the differences you have observed 
between the intestinum jejunum and the intestinum ileum. 
What are chyme (chymus), chyle (chylus), and intestinal juice 

(succus entericus) 1 



Large or Thick Intestine (Intestinum crassum). (Vide Fig. 256 and 
Spalteholz, pp. 522-524.) 

Make use of models and determine accurately the course of 
the intestinum crassum. Study its different parts : 

(a) Blind intestine (intestinum caecum). What are the foetal, infantile, 



486 LABORATORY MANUAL OF HUMAN ANATOMY 

and adult types of caeca? How does the caecum differ in carnivora 
and herbivora? (Vide Poirier et Charpy, t. iv. p. 323.) 

(b) Vermiform process or appendix (processus vermiformis). What is 

the average length of the appendix? What is its relation to the 
caecum? What positions may the process occupy? 

(c) Colon. 

(ca) Ascending colon (colon ascendens). 

(cb) Right colic flexure (ftexura coli dextra). 

(cc) Transverse colon (colon transversum) . 

(cd) Left colic flexure (ftexura coli sinistra). 

(ce) Descending colon (colon descendens}. 

(cf) Sigmoid colon (colon sigmoideum) (0. T. sigmoid flexure). 

Note carefully the relation of each of these parts to the neigh- 
boring viscera. Note especially the relation to the kidneys, duo- 
denum, pancreas, stomach, and spleen. 

Free the remaining portions of the intestine, as far as the left 
sacro-iliac synchondrosis. Apply two ligatures there and cut 
between. Take the intestines to the sink, remove the ligatures, 
and wash out the contents. Then proceed to the study of the 
following external features (cf. Fig. 256) : 

(a) Bands of the colon (taeniae coli}. 

(aa} Mesocolic band (taenia mesocolica). 

(ab) Omental band (taenia omentalis). 

(ac) Free band (taenia liber a). 

Note the relation of the taeniae to the base of the appendix and 
the caecum. Compare specimen with models and determine the 
number of taeniae to be found upon the rectum. 

(b) Sacculations of colon (haustra coli). 

Compare the size of the sacculations upon the caecum, colon 
ascendens, and colon sigmoideum. Which are the largest? How 
is their formation explained? 

(c) Epiploic [fatty] appendages (appendices epiploicae). 

How many series do. you find upon the colon ascendens and colon 
descendens? Along which taeniae are they arranged? How many 
series do you find on the colon transversum? 

Eemove a section of the colon ascendens, open it, and clean 
its mucous surface; pin down upon a cork tray and study its 
coats. 

(a) Serous coat (tunica serosa). Has the colon ascendens a complete 

serous coat? What relation do the appendices epiploicae bear to 
this coat? 

(b) Muscular coat (tunica muscularis). 

(ba) Longitudinal layer (stratum longitudinale) . 

Note that the longitudinal muscular fibres are collected 
together, forming the taeniae. A complete, but thin, con- 
tinuous longitudinal layer of muscle will also be found. 

(bb) Circular layer (stratum circular e). 



ABDOMEN AND PELVIS 



487 



(c) Submucous coat (tela submucosa). 

(d) Mucous coat (tunica mucosa). 

(da) Muscular layer of mucosa (lamina muscularis mucosae). 

(db) Solitary lymph-nodules (noduli lymphatici solitarii). 

(dc) Intestinal glands of Lieberkuehn (Gl. intestinales [Lieber- 

kuehni] ) . 

What are the semilunar folds (plicae semilunares coli) ? 



FIG. 256. 
Taenia libera 



Taenia mesocolica 




Mesocolon 



Plicae semilunares coli 

A piece of the large intestine, intestinum crassum, partly opened along the line of attachment of 
the mesocolon. The bowel is in a state of contraction. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., 
p. 427, Fig. 704.) 



Note carefully the differences between the mucous membrane 
of the large and small intestines and tabulate these in your 
drawing-book. 

Open the anterior and right wall of the caecum and study the 
valve of the colon (valvula coli) (0. T. ileocaecal valve). (See 



488 



LABORATORY MANUAL OF HUMAN ANATOMY 



Fig. 257.) What is the general direction of the valve? What 
coats of the intestine enter into its formation 1 
Note 

(a) Inferior lip (labium inferius}. 

(b) Superior lip (labium superius}. 

(c) Frenula ("bridles" or "reins") of valve of colon (frenula valvulae 

coli). 

What is the function of the valve? 

Note the location of the opening of the vermiform process 
into the caecum. Is it guarded by a valve (valvula processus 
vermiformis} ! This valve was first fully described by Gerlach 



FIG. 257. 

Plicae semilunares coli 




valvulae coli 



,' Terminal part of the intestinum ileum 



Frenulum posterius valvulae coli 



Valvula processus vermiformis 

The intestinum caecum hardened in formalin and cut open in a plane passing through the entrance 
of the intestinum ileum (valvula coli). The latter is closed and is cut in a frontal plane. (After Toldt, 
Anat. Atlas, Wien, 1900, 2 Aufl., p. 428, Fig. 709.) 

in 1847. According to him, it is found in the embryo, but only 
vestiges of it occur in the adult. Laffargue thinks that the for- 
mation of this valve is pathological and is due to mechanical 
pressure exerted by enteroliths in the lumen of the appendix. 
The lumen of the appendix tends to become obliterated in the 
adult. (Vide Fitz, Am. J. Med. Sc., 1886.) 

Open the vermiform process along its mesenteriolic border 



ABDOMEN AND PELVIS 489 

and study its internal structure. Examine the aggregated nod- 
ules of the vermiform process (noduli lymphatici aggregati pro- 
cessus vermiformis). Good specimens for study can be made 
by blowing up the caecum and lower part of the colon ascendens ; 
when dry, windows can be cut out to expose the interior. 

Structures in the Omentum Minus. (See Fig. 258.) 

Elevate the anterior margin of the liver and stitch it to the 
lower margin of the thorax. Then remove, by blunt dissection, 
the anterior layer of the hepatoduodenal ligament (lig amentum 
hepatoduodenale) and study 

(a) Common bile-duet (ductus choledochus). 

Make frequent use of models to complete this study. 
Dissect out carefully the duct, as far as its entrance into the 
wall of the duodenum. What is its general direction? 
Does the direction of the canal depend upon the form of 
the duodenum? To what vertebra is it related above and 
below ? 

Notice that the duct may be divided for descriptive pur- 
poses into a duodenal, a pancreatic, and a parietal portion. 
What is the course of the pancreatic division? Determine 
accurately the relations of the duct to the vena cava infe- 
rior, the fascia of Treitz, the termination of the V. mesen- 
terica superior, the ductus accessorius and ductus pan- 
creaticus. 

Now clean this duct towards the liver and examine 

(aa) Hepatic duct (ductus hepaticus). Notice the two biliary 

ducts passing from the porta hepatis and uniting to form 
the hepatic duct. Determine their relation to other struct- 
ures found here. Are any aberrant vessels of the liver 
(vasa aberrantia hepatis) present? 

(ab) Cystic duct (ductus cysticus}. Determine its relation to the 

gall-bladder (vesica fellea). 

The study of this duct will be completed when the dis- 
section of the liver is made. 

(b) Portal vein (vena portae). (Vide Spalteholz, Fig. 498.) 

Exercise great care in cleaning this vein. Free the pan- 
creas from the posterior abdominal wall; disturb its rela- 
tions as little as possible. Determine the relation of the 
portal vein to the head of the pancreas and the first or 
superior portion of the duodenum (pars superior duodeni). 
Supplement dissection by use of models. Examine the fol- 
lowing tributaries: 

(ba) Coronary vein of stomach (V. coronaria ventriculi). 

(bb) Superior mesenteric vein (V. mesenterica superior), 
(be) Inferior mesenteric vein (V. mesenlcrn-n inferior}. 

The tributaries of the last two veins have been studied in 
the earlier dissection. 



490 LABORATORY MANUAL OF HUMAN ANATOMY 

(bd) Lienal or splenic vein (V. lienalis). 

(bda) Short gastric veins (Vv. gastricae breves}. 

(bdb) Left gastro-epiploic vein (V. gastro-epiploica sin- 

istra). 

(bdc) Cystic vein (V. cystica}. 

(be) Parumbilical veins (Vv. parumbilicales [Sappeyi]). 

What are the following anastomoses in the domain of the V. 
portae ? 

(1) Oesophageal anastomosis. 

(2) Rectal anastomosis. 

(3) Peritoneal anastomosis (veins or system of Retzius). 

(4) Umbilical anastomosis (veins of Sappey). What is the 

" caput medusae," sometimes met with when the V. portae 
is obstructed in the liver? 
Are any of the accessory portal veins present? 

(1) Deep cystic veins, passing from the fossa vesicae felleae and 

the non-peritoneal surface of the gall-bladder directly into 
the liver. 

(2) Epiploic veins, passing from the omentum minus and the 

hepatocolic and hepatorenal ligaments. 

(3) Veins of the hilus. 

(4) Veins from the diaphragm, which pass through the coronary 

ligament of the liver. 

(5) Veins of the ligamentum falciforme hepatis. 

(c) Hepatic artery (A. hepatica). (Vide Spalteholz, Fig. 464.) 

(ca) Right gastric artery (A. gastrica dextra). 

(cb) Proper hepatic artery (A. hepatica propria). 

(cba) Right branch (ramus dexter}, 
(ebb) Cystic artery (A. cystica). 
(cbc) Left branch (ramus sinister). 

(cc) Gastroduodenal artery (A. gastroduodenalis) . 

(cca) Superior pancreaticoduodenal artery (A. pancreati- 

coduodenalis superior). 

(1) Pancreatic branches (rami pancreatici) . 

(2) Duodenal branches (rami duodenales). 

(ccb) Right gastro-epiploic artery (A. gastro-epiploica 

dextra). 

(1) Epiploie branches (rami epiploici). 

Later this artery (right gastro-epiploic) will be 
traced back to its origin, the coeliac artery (A. 
coeliaca). Pay especial attention to the relations of 
the hepatic artery to the ductus choledochus and 
vena portae. What anomalies of the hepatic artery 
frequently occur? 

(d) Hepatic plexus of sympathetic nerves (plexus hepaticus). 

The filaments of this plexus will be found accompanying the 
arteria hepatiea propria and each of its branches. Dissect these 
filaments out and study their distribution. 

(e) Lymph-glands. 

What is the exact position of the cystic lymph-glands (lympho- 
glandulae cysticae} and the lymph-gland of the portal vein 






ABDOMEN AND PELVIS 



491 



(lymphoglandula venae portae)! (Vide Bardeleben, Haeckel u. 
Frohse, Atlas der Topographischen Anatomie des Menschen, 2 Aufl., 
Fig. 111.) 

Look for hepatic lymph-glands (lymphoglandulae hepaticae). 



FIG. 258. 

A. phrenica inferior sinistra 
A. gastrica sinistra ! 

A. coeliaca ! 

A. phrenica inferior dextra 
A. hepatica 



Kami oesophagei 



V. cava inferior 



A. hepatica f Ramus sinister 
propria ( Ramus dexter \ 



A. cystica 



A. hepatica 
propria 



V. portae 

Ductus 
choledochtu 

A. gastrica 
dextra 



A. gastro- 
duodenalis 



Ren dexter 



A. gastro-epi- 
ploica dextr 




Aorta abdom- 

inalis 

A. lienalis 



Lien 



Ramus 
lienalis of the 

A. lienalis 
Pancreas 

A. gastro-epi- 
ploica sinistra 



Rami epiploici 



The tri-partition of the coeliac artery, Tripus coeliacus (Halleri), shown from in front after removal of 
the lesser omentum. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 576, Fig. 952.) 

Coeliac Artery (Arteria coeliaca) and its Branches. (Fig. 258.) 
Trace the hepatic artery, the main branches of which have 

already been dissected out, back to its parent stem, the coeliac 

artery (A. coeliaca) (0. T. coeliac axis). 

Note its exact relations to the vertebrae, pancreas, etc. Dis- 



492 LABORATORY MANUAL OF HUMAN ANATOMY 

sect out carefully the sympathetic nerves (plexus coeliacus) ac- 
companying this artery and its branches. Preserve these as 
far as possible. Examine the origins of the following branches : 

(a) Left gastric artery (A. gastrica sinistra). 

(aa) Oesophageal branches (rami oesophagi). 

(b) Hepatic artery (A. hepatica). The branches of this artery have 

already been traced to their destinations. 

(c) Lienal or splenic artery (A. lienalis). This artery can be seen to the 

best advantage if the stomach is turned upward towards 
the thorax. Note carefully its relations to the pancreas and 
the pancreaticolienal and lienorenal ligaments. 

(ca) Pancreatic branches (rami pancreatici) . 

(cb) Left gastro-epiploic artery (A. gastro-epiploica sinistra). 

(cc) Short gastric arteries (Aa. gastricae breves). 

(cd) Splenic branches (rami lienales). 

Duodenum. (Vide Figs. 259, 261, 262, and Spalteholz, Fig. 563.) 

Study this part of the small intestine in your cadaver and 
compare it with the His models. 

Divisions and angles. 

(a) Superior part (pars superior), or first portion. 

(b) Descending part (pars descendens), or second portion. 

(c) Inferior part (pars inferior). 

(ca) Horizontal part (pars horizontalis [inferior}), or third 

part. 

(cb) Ascending part (pars ascendens), or fourth part. 

(d) Superior duodenal flexure (flexura duodeni superior). 

(e) Inferior duodenal flexure (flexura duodeni inferior). 

(f) Duodenojejunal flexure (flexura duodenojejunalis). 

Three types of duodena are described. 

(1) The annular type is met with in the second half of foetal life (Toldt). 

It is found almost always in the infant and is known as the infan- 
tile type of Jonnesco. Occasionally it persists to adult life. 

(2) The U-shaped. The pars inferior is very long. 

(3) The V-shaped. The pars descendens passes down almost vertically. 

The ascending portion passes upward and to the left, making an 
angle of 25 to 40 with the descending part. The pars horizon- 
talis is lacking. 

In what subdivisions of the abdomen is the duodenum sit- 
uated? What is its relation to the upper and lower abdominal 
compartments and to the right and left colon pockets (separated 
by the radix mesenterii) ? 

How is it related to the liver, the pancreas, the ductus chole- 
dochus, the vertebrae, the right and left kidneys, the superior 
mesenteric artery and vein, the right spermatic artery, etc. ? 



ABDOMEN AND PELVIS 



493 



What are its peritoneal relations? Examine 

(a) Duodenorenal ligament (ligamentum duodenorenale) . 

(b) Duodenocolic ligament (ligamentum duodenocolicum) . (Inconstant.) 

The latter has been dissected away. Examine model and other 
cadavers and determine its location, if present. 



FIG. 259. 



Pars superior duodeni- 
Flexura duodeni superior -- 



Papilla duodeni 
(Santorini) 



Pars descendens ._ 
duodeni 

Noduli lymph- 
atici solitarii 

Plica longitudi-.- 
nalis duodeni 



Plicae circulares_.~ 
(Kerkringi) 



Flexura duodeni 

inferior 




.Pylorus 

-Pars pylorica ventriculi 



Flexura dupdeno- 
jejunalis 



-Intestinum 
jejunum 



Pars ascendens duodeni 



Pars horizontalis (inferior) 
duodeni 



The duodenum seen from in front. The descending part has been cut open and its anterior wall 
turned back to the left. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 424, Fig. 694.) 



The duodenum is never displaced en masse, for the flexura 
duodenojejunalis is attached to the vertebral column. The first 
two portions are often displaced laterally or prolapsed second- 
ary to the downward displacement of the stomach and liver. 
Determine by what means the duodenum is held in position. 

Dissect out the suspensory muscle of the duodenum (M. sus- 
pensorius duodeni). 

This muscle was described by Treitz in 1853. It arises from the supe- 
rior border of the flexura duodenojejunalis and the superior half of the 
pars ascendens. Passing upward behind the head of the pancreas and in 
front of the aorta, it is attached to the left pillar of the diaphragm by a 
tendon composed of elastic and fibrous tissue. It is composed of smooth 
muscle-fibres. According to Braune, it is derived from both coats of the 
intestine. 



494 LABORATORY MANUAL OF HUMAN ANATOMY 

Incise the ductus choledochus, the ductus pancreaticus [Wir- 
sungi], and the ductus pancreaticus accessorius [Santorini], 
pass probes (or broom-straws) through these into the duodenum ; 
just below the pylorus, apply two ligatures about the duodenum, 
cut between, and remove the duodenum from the abdomen. Re- 
move ligatures, wash the lumen out carefully, incise along the 
convex margin, and study in the duodenum 

(a) Circular folds (plicae circular -es [Kerkringi]). 

( b ) Intestinal villi ( villi intestinales ) . 

(c) Solitary lymph-nodes (noduli lymphatici solitarii). 

(d) Duodenal papilla (papilla duodeni [Santorini]). 

(e) Longitudinal fold of duodenum (plica longitudinalis duodeni}. 

Note that this fold is formed by the ductus choledochus and leads 
up to the common opening of the ductus choledochus and ductus 
pancreaticus. 

Spread the duodenum out upon a cork dissecting tray, pin it 
down, and study its coats. 

(a) Serous coat (tunica serosa). 

(b) Muscular coat (tunica muscularis). 

(ba) Longitudinal layer (stratum longitudinale) . 

(bb) Circular layer (stratum circular e}. 

(c) Submucous coat (tela submucosa). 

(d) Mucous coat (tunica mucosa}. 

(da) Muscular layer of the mucosa (lamina muscularis mucosae). 

(db) Proper mucous coat (tunica propria mucosa). 

FIG. 260. 

Ductus pancreaticus [Wirsungi] 

M. sphincter duct. pan. > . cho]edoch 

Ductus choledochus 




v Fibrae longae 
M. sphincter Duct, choledbch. 

Sphincter muscle of the ductus choledochus and of the ductus pancreaticus in man (after Hendrick- 
son). (From Poirier et Charpy, Traite d'Anat. hum., Paris, 1901, 2 ed., t. iv. p. 796, Fig. 411.) 

Use a lens and look for the duodenal glands of Brunner (Gl. 
duodenales [Brunneri] ) in the tela submucosa. 

Throw the lower end of the ductus choledochus and a small 
adjacent portion of the duodenum into a dish containing equal 
parts of nitric acid, alcohol, and glycerin for a few hours. Then 
transfer to water, and with delicate instruments isolate the 



ABDOMEN AND PELVIS 



495 



sphincter muscle of the bile-duct. (Cf. Fig. 260, and Hendrick- 
son's description.) 

Pancreas. (Vide Figs. 261-3, and Spalteholz, Figs. 584, 585.) 

Review the embryology of the pancreas. What are the ventral and 
dorsal anlages? (Vide Kollmann, Entwickelungsgeschichte des Menschen, 
p. 370.) 

Study the pancreas in your cadaver and make frequent use 
of models and atlases. The secretion of the gland is called the 
pancreatic juice (succus pancreaticus) . 



FIG. 261. 



Apex suprarenalis. . . 
(gl. dextrae) 



V. portae - - - 



Glandnla suprarenalis (sinistra) 

, Ren (sinister) 

,.Lien 
Pancreas 




Ren (dexter) 



Pars descend- 
ens duodeni 



A. mesenteric-a supeiior 

Relations of the pancreas. After models by His. The contour of the stomach is projected in red. 
(From Poirier et Charpy, Trait6 d'Anat. hum., Paris, 1901, 2 ed., t. iv. p. 806, Fig. 415.) 

Divisions. 

(a) Head of pancreas (caput pancreatis). 

(b) Uncinate process (processus uncinatus [pancreas Winslowi] ) . 

(c) Notch of the pancreas (incisura pancreatis). 

(d) Body of pancreas (corpus pancreatis). 

(da) Anterior surface (fades anterior). 

(db) Posterior surface (fades posterior). 



496 



LABORATORY MANUAL OF HUMAN ANATOMY 



(e) 



(dc) Inferior surface (fades inferior). 

(dd) Superior margin (margo superior}. 

(de) Anterior margin (margo anterior). 

(df) Posterior margin (margo posterior). 
Omental tuber (tuber omentale). 

Tail of pancreas (cauda pancreatis). 



Relations. 

Note carefully the relations of the pancreas to the lumbar ver- 
tebrae, the stomach, the left kidney, the spleen, the superior 
mesenteric vessels, the splenic vessels, the inferior mesenteric 
vein, the ligamentum pancreaticolienale, and the duodenum. 
What are " fasciae of fusion," and what relation has the pancreas 
to such? (Vide Figs. 263, A and B.) Dissect away some of the 
parenchyma of the gland and determine, if possible, the source 
and relations of the pancreatic ducts : 1 



FIG. 262. 



Ductus pancreaticus accessorius [Santorini] 
Bristle in the ductus pancreat. access. 



Orificium ductus 

pancreat. access. 

[Santorini] 




Ductus pancreaticus [Wirsungi] 
Vasa mesenterica superiora 
Ductus pancreaticus [Wirsungi] 



Orificium ductus 
pancreatici 

Duodenal openings of the ductus pancreaticus [Wirsungi] and ductus pancreaticus accessorius 
[Santorini]. (After Schiomer.) A bristle has been passed into the accessory duct. (From Poirier et 
Charpy, Traite 1 d'Anat. hum., Paris, 1901, 2 ed., t. iv. p. 811, Fig. 417.) 

(a) Pancreatic duet of Wirsung (ductus pancreaticus [Wirsungi]). 

(b) Accessory pancreatic duct of Santorini (ductus pancreaticus acces- 

sorius [Santorini] ) . 



Is an " accessory pancreas 
ent? 



(pancreas, - access orium) pres- 



1 For a method of studying the pancreatic ducts, see " Pancreatic Ducts in 
the Dog," by D. G. Revell, in Amer. Jour. Anat., vol. i. p. 443. 



ABDOMEN AND PELVIS 



497 



Vagus Nerves (O. T. Pneumogastric Nerves). (Vide Toldt, Fig. 
1322.) 

Depress the stomach and bring well into view the abdominal 
part (pars abdominalis) of the oesophagus. Dissect out care- 
fully the nerves descending upon the anterior and posterior sur- 



Omentum minus 
A. hepatica propria 
Ductus choledochus 



A. hepatica 
Caput pancreatis 



FIG. 263. 
A 

A. gastrica sinistra 



Paries abdom. post. 
Peritonaeum parietale 

Ren (dexter) 




Ventriculus 
Corpus pancreatis 



. gastrO;epiploica 
sinistra 



Lien 



Aorta 



V. cava inferior 



A. hepatica propria 
Ductus choledochus 



V. portae 



A. hepatica. 

Fusion of the caput pancreatis 

to the paries abdominis (fascia 

of Treitz) 



B 

Omentum minus 

A. gastrica sinistra 



Paries abdom. post. . 
Peritonaeum parietale 

Ren (dexter) 




Ventriculus 

Corpus pancreatis 
Fusion of the corp. pan. to the 
mesoduodenum and to the 
posterior abdominal wall 
A. gastro-epiploica sinistra 
Lig. gastrolienale 

Lien 



Aorta 
Cap. pan. 
V. cav. inf. 



Lig. pancreaticoduodenale 



Section passing through the hepatic arch, above the pylorus and through the body and head of the 
pancreas, to show the situation and origin of the " fasciae of fusion." The pancreatic plica is to be seen 
above and to the left of the hepatic. In A the fusions have been destroyed and the mesos thereby 
restored to their primitive independence. In B the adult type is shown. The caput pancreatis and the 
mesoduodenum lodging it have been turned over to the right. The corpus et cauda pancreatis, contained 
within the omentum ma jus, lie iu front of the caput pancreatis on the right side, and in front of the 
posterior abdominal Avail on the left. In B the retropancreatic " fasciae of fusion " may be seen (the 
fascia of Trietz behind the caput pam-roatis, the fascia of Toldt behind the corpus pancreatis). (From 
Poirier et Charpy, Traite" d'Anat. hum., Paris, 1901, 2 ed., t. iv. p. 976, Fig/548 A and B.) 

32 



498 LABORATORY MANUAL OF HUMAN ANATOMY 

faces and trace these upon the stomach. Some filaments will 
have been destroyed in the earlier dissections. 

In connection with the abdominal part of the vagus nerve 
(N. vagus) study 

(a) Gastric branches (rami gastrici). 

(b) Anterior gastric plexus (plexus gastricus anterior). 

(c) Posterior gastric plexus (plexus gastricus posterior). 

(d) Hepatic branches (rami hepatici). 

(e) Coeliac branches (rami coeliaci). 

(ea) Splenic branches (rami lienales). 

(eb) Renal branches (rami renales). 

Stomach (Ventriculus). (Vide Spalteholz, Figs. 557-560.) 

Pass two ligatures about the abdominal portion of the 
oesophagus, cut between, and remove the stomach. Use models 
to determine its exact form, position, relations, etc. What is the 
direction of the axis of this organ? Note that the upper two- 
thirds is vertical, while the lower one-third passes to the right, 
upward and slightly backward. These two parts make an angle 
with each other which varies between 60 and 70. For a full 
discussion concerning the exact position of these two parts, con- 
sult the systematic text-books. 
Examine 

(a) Anterior wall (paries anterior). 

(b) Posterior wall (paries posterior). 

(c) Greater curvature of stomach (curvatura ventriculi major). 

(d) Lesser curvature of stomach (curvatura ventriculi minor). 

(e) Cardia (cardia). 

(f) Fundus of stomach (fundus ventriculi). 

(g) Body of stomach (corpus ventriculi). 
(h) Pylorus (pylorus). 

(i) Cardiac part (pars cardiaca). 
(j) Pyloric part (pars pylorica). 
(k) Cardiac antrum (antrum cardiacum). This is only occasionally 

present. 
(I) Pyloric antrum (antrum pyloricum). 

How much of the stomach is to the left of the median plane T 
How much to the right ? What is the relation of the cardia to the 
sternal extremity of the seventh costal cartilage on the left side ? 
What is the relation of the pylorus to the median plane and to 
the umbilicus? Draw a line uniting the medial extremities of 
the ninth costal cartilages. What is the position of the pylorus 
in relation to this line? What is the position of the greater 
curvature? Does it vary? The relation of the stomach to each 



ABDOMEN AND PELVIS 



499 



neighboring viscus as shown in the models should be carefully 
studied. 

What is the " semilunar space of Traube"? What is a biloc- 
ular or hour-glass stomach? Fill the stomach with water and 
determine its capacity. Does the axis of the stomach change 
when filled ? 

FIG. 264. 



Tunica mucosa 




Lamina muscularis 
mucosae 



Tela submucosa 



Strat circ. 



Tun. 
muse. 



Strat. long. 



Transverse section of the wall of a dog's stomach. (After Mall. ) On the right the tunics are super- 
imposed, on the left the vessels and vascular plexuses are shown. (From Poirier et Charpy, Trait6 
d'Anat. hum., Paris, 1901, 2 ed., t. iv. p. 229, Fig. 122. ) 

Open the stomach along its greater curvature, spread it out, 
pin it down upon a cork dissecting tray, and study its coats and 
the valve and muscle derived from them. (Cf. Fig. 264.) Also 
consult " The Vessels and Walls of the Dog's Stomach," by 
Professor Mall, in Johns Hopkins Hosp. Reports, vol. i. p. 1. 



500 LABORATORY MANUAL OF HUMAN ANATOMY 

(a) Serous coat (tunica serosa). 

(b) Muscular coat (tunica muscularis). 

(ba) Longitudinal layer (stratum longitudinale) . 

(bb) Pyloric ligaments (Ligg. pylori}, 
(be) Circular layer (stratum circular e}. 

(bd) Sphincter muscle of pylorus (M. sphincter pylori). 

(be) Oblique fibres (ftbrae obliquae). 

(c) Pyloric valve (valvula pylori). 

(d) Submucous layer (tela submucosa). 

(e) Mucous coat (tunica mucosa). Can you make out the lamina muscu- 

laris mucosae? 

(ea) Gastric areas (areae gastricae). 

(eb) Mucous folds (plicae mucosae). 

(ec) Gastric pits (foveolae gastricae). 

(ed) Gastric lymph-nodules (noduli lymphatici gastrici). 

With a loop (lens) look at the openings of the gastric glands. 

(a) [Proper] gastric glands (glandulae gastricae [propriae]). 

(b) Pyloric glands (glandulae pyloricae). 

There are only a few true " cardiac 7 ' glands in the human 
stomach. (Cf. Bensley, E. R., " The Cardiac Glands of Mam- 
mals, " Am. J. Anat., Bait., 1902, vol. ii. p. 105.) 

The mixed secretion of the glands is called the gastric juice 
(succus gastricus). 

Abdominal Part of Sympathetic System (Pars abdominalis S. sym- 
pathici). (Vide Toldt, Fig. 1332.) 

Dissect out carefully the sympathetic nerves and ganglia sit- 
uated about the coeliac artery. Determine the course of the dif- 
ferent plexuses which surround the arteries given off from the 
main trunk. 

(a) Coeliac plexus (plexus coeliacus). 

(b) Coeliac ganglia (ganglia coeliaca). 

(c) Phrenic plexus (plexus phrenicus). 

(ca) Phrenic ganglia (ganglia phrenica). 

(d) Hepatic plexus (plexus hepaticus). 

(e) Splenic plexus (plexus lienalis). 

(f) Renal plexus (plexus renalis). 

(g) Suprarenal plexus (plexus suprarenalis) . 

(h) Superior gastric plexus (plexus gastricus superior), 
(i) Inferior gastric plexus (plexus gastricus inferior). 

The two latter have been destroyed in the removal and dissection 
of the stomach. Examine models to determine their exact position 
and the arteries that they accompany. 

Dissect carefully the abdominal aorta and study 

(j) Abdominal aortic plexus (plexus aorticus abdominalis). It has 
already been examined. 



ABDOMEN AND PELVIS 501 

What is the relation between the ganglia coeliaca and the Nn. 
splanchnici majores ? What are the lesser splanchnic nerve (N. 
splanchnicus minor) and its renal branch (ramus renalis)! 
These nerves are studied in the upper part of their course in 
the dissection of the thorax. 

FIG. 265. 

Curvatura ventriculi major 

. .- Extremitas superior 

.Facies gastrica 




^^^^ __ "^Hr Extremitas inferior 

^ 

Hilus lienis 

, Lien accessorius (Var.) 

Ligamentum gastrolienale 

The spleen in conjunction with the ligamentum gastrolienale. Seen from in front. (After Toldt, 
Anat. Atlas, Wien, 1900, 2 Aufl., p. 434, Fig. 723.) 

Spleen (Lien). (Vide Figs. 261, 263, 265, and Spalteholz, Fig. 587.) 

Eemove the spleen from your subject. It has already been 
examined in position in the cadaver. Examine models to deter- 
mine the exact position of the organ in cadavers with the organs 
hardened in situ and its relation to vertebrae, ribs, and neighbor- 
ing viscera. Note the following: 

Surfaces. 

(a) Diaphragmatic surface (fades diaphragmatica) . 

(b) Renal surface (fades renalis). 

(c) Gastric surface (fades gastrica). 

Extremities. 

(a) Superior extremity (extremitas superior). 

(b) Inferior extremity (extremitas inferior). 



502 LABORATORY MANUAL OF HUMAN ANATOMY 

Margins. 

(a) Posterior margin (margo posterior}. 

(b) Anterior margin (margo anterior). 

Note especially the crenations in this anterior border. It is 
often referred to as the ' 'margo crenatus." These crenations 
are of importance, as they enable the clinician to differentiate 
between enlargement of the spleen and of the kidney. The 
rounded prominence separating the gastric and renal surfaces 
is sometimes described as the margo intermedius. 

Examine the hilus of the spleen (hilus lienis}. 

Four layers of peritoneum will be found at the hilus. The 
two anterior layers are derived from the ligamentum gastro- 
lienale, while the two posterior layers are derived from the liga- 
mentum pancreaticolienale. Determine from which peritoneal 
sac each layer of this peritoneum is derived, noting that the 
relation is the same as found in the omentum majus. Between 
the two layers of the ligamentum pancreaticolienale will be found 
the tail of the pancreas and the splenic vessels. 

Incise the spleen and examine 

(a) Serous coat (tunica serosa). 

(b) Albugineous coat (tunica albuginea). 

(c) Splenic pulp (pulpa lienis). 

(d) Splenic rami of splenic artery (rami lienales [arteriae lienalis]). 

(e) Splenic lymph-nodules (noduli lymphatici lienales [Malpighii]) (0. 

T. Malpighian corpuscles). 

Instructive pictures of the splenic framework can be obtained 
by allowing the organ to decompose partially and then washing 
out the pulp and blood and drying by inflation through one of the 
veins. 

What is an accessory spleen (lien accessorius) ? How many 
of these may be found, and where are they generally located? 

Review the development of the spleen and its relation to the 
mesogastrium posterius. 

Liver (Hepar). (Vide Figs. 266, 267, and Spalteholz, Figs. 579-581.) 
Eeview the development of the liver. Its position in the 
cadaver has already been studied. Use models to determine its 
exact relations, form, and position in a hardened body. Remove 
the liver from the abdominal cavity. Cut through the liga- 
mentum teres and ligamentum falciforme. Divide the triangular 
ligaments on each side and the upper layer of the coronary liga- 
ment. Separate the posterior surface of the liver from the dia- 



ABDOMEN AND PELVIS 



503 



phragm by blunt dissection, noting the amount of areolar tissue. 
Next divide the vena cava inferior and the lower layer of the 
coronary ligament. The inferior vena cava must be divided a 
second time at the point where it first comes in contact with this 
viscus before the liver can be removed from the abdominal cavity. 



Lobes, 
(a) 

w 

(c) 



(d) 



Right lobe of liver (lobus hepatis dexter). 
Quadrate lobe (lobus quadratus). 
Caudate lobe (lobus caudatus [Spigeli]). 

(ca) Papillary process (processus papillaris). 

(cb) Caudate process (processus caudatus). 
Left lobe of liver (lobus hepatis sinister). 



FIG. 266. 
Vv. hepaticae 



Vena cava inf. 
Lig. ven. [Arantii] 




Lig. teres hepat. 

Ductus hepat. 

Duct. cyst. 

The liver, from behind and below. (From Gegenbaur, Lehrb. der Anat. des Mensch., Leipzig, 
1899, 7 Aufl., Bd. ii. p. 75, Fig. 401.) 

Surfaces. 

(a) Superior surface (fades superior). 

(b) Posterior surface (fades posterior). 

(c) Inferior surface (fades inferior). 

Ligaments. 

(a) Round ligament of liver (ligamentum teres hepatis). 

(b) Venous ligament (ligamentum venosum [Arantii]). 

(c) Falciform ligament (ligamentum f aid forme hepatis). 

(d) Coronary ligament (ligamentum coronarium hepatis). 

(e) Right triangular ligament (ligamentum triangular -e dextrum). 

(f) Left triangular ligament (ligamentum triangulare sinistrum). 



504 



LABORATORY MANUAL OF HUMAN ANATOMY 



Impressions. 

(a) Cardiac impression (impressio cardiaca). 

(b) Oesophageal impression (impressio oesophagea). 

(c) Gastric impression (impressio gastrica). 

(d) Duodenal impression (impressio duodenalis). 

(e) Colic impression (impressio colica). 

(f) Renal impression (impressio renalis). 

(g) Suprarenal impression (impressio suprarenalis) . 

FIG. 267. 



Sinus phrenico 
costalis 



Diaphragma. 




- Pulmo 



Sinus phrenico- 
costalis 



-- Lig. coronarium 



Ren (dexter) 



Colon transv..- 



Sagittal section through the liver. The section passes through the regio hypochondriaca dextra, 
(From Poirier et Charpy, TraittS d'Anat, hum., Paris, 1901, 2 ed., t. iv. p. 711, Fig. 367.) 



Fossae. 

(a) Right sagittal fossa (fossa sagittalis dextra). 

(aa) Fossa for gall-bladder (fossa vesicae felleae). 

(ab) Fossa for vena cava (fossa venae cavae). 

(b) Left sagittal fossa (fossa sagittalis sinistra). 

(ba) Fossa for umbilical vein (fossa venae umbilicalis). 

(bb) Fossa for venous duct (fossa ductus venosi). 

Examine also 

(a) Anterior margin (margo anterior). 

(b) Omental tuber (tuber omentale). 

(c) Umbilical notch (incisura umbilicalis). 

(d) Fibrous appendix of liver (appendix fibrosus hepatis). 



ABDOMEN AND PELVIS 505 

Make several incisions in the liver from right to left. Do not 
injure the gall-bladder. Examine first with naked eye and then 
with a loop 

(a) Lobules of liver (lobuli hepatis). 

(b) Fibrous capsule of Glisson (capsula fibrosa [Glissoni]). 

(c) Interlobular arteries (rami arteriosi interlobulares) . 

(d) Interlobular veins (venae interlobulares) . 

(e) Central veins (venae centrales). 

How can you differentiate (d) and (e) from each other? 
(/) Bile-ducts (ductus biliferi) (0. T. bile canaliculi). 
(g) Interlobular ducts (ductus interlobulares}. 

What are costal and diaphragmatic sulci in the liver ! What 
is the general direction of these, when present! What is a 
" Kiedel's lobe" in the liver? 

Note the exact peritoneal relations, determining how much 
of the liver is not covered by peritoneum. 

Gall-bladder (Vesica fellea). 
Study- 

(a) Fundus of gall-bladder (fundus vesicae felleae). 

(b) Body of gall-bladder (corpus vesicae felleae). 

(c) Neck of gall-bladder (collum vesicae felleae}. 

Is the gall-bladder completely covered by peritoneum? 

Open the gall-bladder and dissect out the following coats : 

(a) Serous coat (tunica serosa vesicae felleae}. 

(b) Muscular coat (tunica muscularis vesicae felleae). 

(c) Mucous coat (tunica mucosa vesicae felleae). 

(ca) Folds of mucous coat (plicae tunicae mucosa vesicae felleae). 

Note the relation of the cystic duct to the gall-bladder. Open 
it and study the spiral valve of Heister (valvula spiralis [Heis- 
teri]). How far does it extend in your subject? What coats 
take part in the formation of this valve ? In the biliary mucous 
membrane look for glands (Gl. mucosae biliosae). 



UROPOETIC ORGANS (ORGAN A UROPOETIC A}. 

These include the kidney (ren), ureter, and urinary bladder 
(vesica urinaria). Sometimes the suprarenal gland (Gl. supra- 
renalis) is classed here, but probably incorrectly. 



506 LABORATORY MANUAL OF HUMAN ANATOMY 

Kidney (Ren). (Vide Fig. 271, and Spalteholz, Figs. 634-636.) 

Study the exact relation of the kidneys to the vertebrae, the 
psoas and quadratus lumborum muscles, the twelfth rib, and 
the crest of the ilium. Which kidney is the lower ! How do you 
account for this low position? Note the relation of the right 
kidney to the liver, the duodenum, and the flexura coli dextra, 
and the relation of the left kidney to the pancreas, the stomach, 
the spleen, and the flexura coli sinistra. 

Direction and Orientation. 

The kidney is not vertically placed. Its axis is directed obliquely 
downward and lateralward. The superior extremity approaches the 
median line. The anterior surface is directed lateralward and the pos- 
terior medialward. 

Perirenal Fascia. (Figs. 268 and 269. ) l 

(a) Eetrorenal layer. 

This layer of fascia is found between the posterior surface of 
the kidney and the aponeurosis of the quadratus lumborum 
muscle. It covers the sheath of the psoas muscle, reinforcing it, 
and is attached to the vertebrae and intervertebral disks, medial 
to the attachment of the psoas. It does not become continuous 
with the corresponding fascia of the opposite side. 

(b) Prerenal fascia. 

This layer of fascia follows closely the reflections of the peri- 
toneum about the kidneys. It passes in front of each kidney 
and its corresponding pedicle, the aorta and inferior vena cava, 
to become continuous with the corresponding fascia of the oppo- 
site side. 

If these two fasciae are traced longitudinally, they will be 
found to fuse above and become attached to the diaphragm. 
Below, fusion does not occur; the anterior layer follows the 
reflections of the peritoneum, while the posterior layer divides 
into several lamellae which fuse with the cellular tissue of the 
iliac fossa. 

Vessels of the Kidney. 

In injected specimens study 

Arteries of Kidney (Arteriae renales). 

(a) Interlobar arteries of kidney (Aa. interlobares renis). 

(aa) Arciform arteries or renal arches (Aa. arci formes) . 

(ab) Interlobular arteries (Aa. interlobulares) . 

1 For a description of the perineal fascia, consult " The Present Conception 
of the Perineal Fascia and its Role in Fixation of the Kidney," by D. D. 
Lewis, in Jour. Amer. Med. Assoc., vol. xlii. p. 701. 



ABDOMEN AND PELVIS 

FIG. 268. 



507 




Retrorenal fascial 
layer 



The perirenal fascia, comprising the two layers, prerenal 
and retrorenal. (After Poirier et Charpy, Traite" d'Anat. 
hum., Paris, 1901, 2 ed., t. v. p. 10, Fig. 6.) 




Diaphragma _ 

Glandula supra 

renalis 



Ren 



Retrorenal _ _ 
layer of 
fascia 



Prerenal layer 
of fascia 



The perirenal fascia as seen 
in a longitudinal section of the 
kidney. Diagrammatic. (After 
Poirier et Charpy, Traite 1 d'Anat. 
hum., Paris, 1901, 2 ed., t. v. p. 11, 
Fig. 7.) 



FIG. 269. 



Int. colon- - 



Peritonaeum parietale 

Prerenal fascia -- 
Retrorenal fascia 




Mesocolon 



Int. colon 

Peritonaeum parietale ^ 

i 

Prerenal fascia _ . 
Retrorenal fascia - - 



The formation of the "fascia of Toldt." The colon being pushed into the posterolateral part of 
the abdominal cavity, (B) has its mesocolon brought into contact with the posterior abdominal wall 
with the peritoneum of which it fuses as indicated by the shading. (After Poirier et Charpy, Traite" 
d'Anat. hum., Paris, 1901, t. v. p. 12, Figs. 8 and 9.) 




508 LABORATORY MANUAL OF HUMAN ANATOMY 

(aba) Afferent vessel (vas afferens). 

(abb) Efferent vessel (vas e/ferens). 

(ac) Capsular branches (rami capsulares). 

(ad) Straight arterioles (arteriolae rectae). 

(ae) Nutrient arteries of renal pelvis (Aa. nutricae pelvis 

renalis). 

Veins of Kidney (Venae renales). 

(a) Interlobar veins (Vv.'interlobares). 

(aa) Arciform veins (Vv. arciformes). 

(ab) Interlobular veins (Vv. interlobulares) . 

(ac) Straight venules (venulae rectae). 

(ad) Stellate veins (venae stellatae) (0. T. veins of Verheyn). 

Examine corrosion preparations of the renal blood-vessels in 
the anatomical museum. 

Examine the adipose capsule (capsula adiposa). Does it 
assist in maintaining the organ in position ? What is the ' ' para- 
renal adipose body ' ' of Gerota ? 

Cut the blood-vessels and ureter some distance from the kid- 
ney and examine 

(a) Lateral margin (mar go lateralis). 

(b) Medial margin (mar go medialis). 

(ba) Renal hilus (hilus renalis). 

(bb) Renal sinus (sinus renalis). 

(c) Anterior surface (fades anterior). 

(d) Posterior surface (fades posterior). 

(e) Superior extremity (extremitas superior). 

(f) Inferior extremity (extremitas inferior). 

(g) Muscular impression (impressio muscularis). 
(h) Hepatic impression (impressio hepatica). 

(i) Gastric impression (impressio gastrica). 

Incise the kidney along its lateral margin, cutting through 
its fibrous capsule (tunica fibrosa). Does it strip readily from 
the surface of the kidney? What is the muscular tunic (tunica 
muscularis) ? 

Divide the kidney into two symmetrical halves. (Of. Spalte- 
holz, Fig. 637.) Study- 

(a) Cortical substance (substantia corticalis). 

(b) Medullary substance (substantia medullaris). 

(c) Renal lobes (lobi renales) (0. T. reniculi). 

(d) Renal pyramids (pyramides renales [Malpighii]) . 

(e) Base of pyramid (basis pyramidis). 

(f) Renal papillae (papillae renales). 

(g) Papillary foramina (foramina papillaria). 
(h) Renal columns (columnae renales [Bertini]). 
(i) Cortical lobules (lobuli corticales). 



ABDOMEN AND PELVIS 509 

(ia) Radiate part (pars radiata [processus Ferreini]) (0. T. pyra- 
mid of Ferrein). 

(ib) Convoluted part (pars convoluta) (0. T. labyrinth). 
(j) Renal corpuscles (corpuscula renis [Malpighii]) . 

(ja) Glomeruli. 

(jaa) Capsula glomeruli. 

(k) Renal pelvis (pelvis renalis). (Fig. 270.) 
(I) Renal calyces (calyces renales}. 

(la) Greater renal calyces (calyces renales majores). 

(Ib) Smaller renal calyces (calyces renales minores). 
(m) Glands of renal pelvis (GL pelvis renalis). 

How can you determine to which side each kidney belongs ? 

Suprarenal Glands (Glandulae suprarenales). (Vide Fig. 271, and 
Spalteholz, Fig. 644.) x 

Study- 

(a) Hilus of suprarenal gland (hilus glandulae suprarenalis) . 

(b) Anterior surface (fades anterior). 

(c) Posterior surface (fades posterior). 

(d) Base of suprarenal gland (basis glandulae suprarenalis). 

(e) Apex of the right suprarenal (apex suprarenalis [Gl. dextrae]). 

(f) Superior margin (mar go superior). 

(g) Medial margin (mar go medialis). 

Cut through the suprarenal gland and study the general char- 
acteristics of 

(a) Cortical substance (substantia corticalis). 

(b) Medullary substance (substantia medullaris). 

Observe the central vein (vena centralis). 

What are accessory suprarenal glands (GL suprarenales ac- 
cessoriae), and where are they most frequently situated! Are 
portions of the suprarenal glands ever found in the kidney 
substance ? 

Ureter. 

Trace the ureter downward into the pelvis. It is divisible 
into an abdominal part (pars abdominalis) and a pelvic part 
(pars pelvina). Study the exact relations of the abdominal part. 
The pelvic division will be studied later during the dissection of 
the pelvic viscera. 

1 Consult " Blood-vessels, Angiogenesis, Organogenesis, Reticulum, and His- 
tology of the Adrenal," by J. M. Flint, in Contributions to the Sci. of Med. by 
the pupils of Win. H. Welch, Baltimore, 1900. 



510 LABORATORY MANUAL OF HUMAN ANATOMY 

FIG. 270. 




Casts of the calices renales, pelvis renalis, and ureter (Poirier). ( From Poirier et Charpy, Traite d' Anat. 
hum., Paris, 1901, t. v. p. 57, Fig. 47.) 



ABDOMEN AND PELVIS 511 

Excise a portion of the abdominal part of the ureter. Make 
a dissection of its different coats, using a loop. 

(a) Adventitious coat (tunica adventitia). 

(b) Muscular coat (tunica muscularis) . 

(ba) External layer (stratum externum). 

(bb) Middle layer (stratum medium), 
(be) Internal layer (stratum internum). 

(c) Mucous coat (tunica mucosa). 

(ca) Mucous glands of ureter (Gl. mucosae ureteris). 



MUSCLES, VESSELS, AND NERVES. 

Diaphragm (Diaphragma). 

Strip the peritoneum from the under surface of the dia- 
phragm, preserving carefully the vessels and nerves which 
ramify on its under surface. Review the development of the 
diaphragm. How do you explain a partial innervation by a 
cervical nerve ? Make a careful study of the architecture of this 
muscle, noticing carefully the form, position, origin, insertion, 
and action of its different parts. (Vide Spalteholz, Fig. 314.) 

(a) Lumbar part (pars lumbalis). 

(aa) Medial crus (crus mediale). 

(ab) Intermediate crus (crus intermedium). 

(ac) Lateral crus (crus laterale). 

(b) Costal part (pars costalis). 

(c) Sternal part (pars sternalis). 

(d) Aortic opening (hiatus aorticus). 

(e) Oesophageal opening (hiatus oesophageus). 

(f) Central tendon (centrum tendineum). 

(g) Opening for vena cava (foramen venae cavae). 

(h) Medial lumbocostal arch (arcus lumbocostalis medialis [Halleri]) 

(0. T. ligamentum arcuatum internum). 
(i) Lateral lumbocostal arch (arcus lumbocostalis lateralis [Halleri]) 

(0. T. ligamentum arcuatum externum). 

Examine the structures passing through the hiatus oesopha- 
geus, the hiatus aorticus, and the foramen venae cavae. What is 
the weak spot of the diaphragm? Where is Larrey's space? 

Abdominal Aorta and Inferior Vena Cava. (Vide Spalteholz, Figs. 

463, 499.) 

Clean these two vessels, avoiding injury to the truncus sym- 
pathicus. The branches of the aorta will not be given in detail 
where they have already been met with in earlier dissections. 



512 



LABORATORY MANUAL OF HUMAN ANATOMY 



FIG. 271. 



Oesophagus 
Kami suprarenales superiores V. cava inferior / 



A. phrenica inferior sinistra 
A. lienalis 



A. coeliaca- 



A. supraren - 
alis inferior 
A. suprarenalis 

media 

A. testicularis. 

(spermatica 

interna) 



A. lumbalis ima 
Ramus iliacus 
of the A. ilio 
lumbalis 
Ureter dexter- 

A. circumflexa 
ilium profunda 

Lig. inguinale 




^Rami lienales 



-Ramus capsularis 
of the A. renalis 



-A. mesenterica 

superior 
--A. mesenterica inferior 

-Aorta abdominalis 
A. lumbalis III. 
A. iliaca communis 



.A. sacralis media 
A. hypogastrica 
_A. iliaca externa 

-Ductus defer ens 

A. spermatica 

externa 
A. testicularis 

V. femoralis 
'"-A. femoralis 

-Funicuhis sper- 

maticus 

A. spermatica 

externa 

V. saphena magna 



A. epigastrica 
inferior 

A. testicularis. - 
A. spermatica 

externa 

Ductus deferens-" 
Plexus pampiniformls 

Fades medialis testis' Tunica vaginalis communis (posterior side) 

The parietal and the paired visceral branches of the abdominal aorta. The abdominal viscera have 
een removed back to the spleen, kidney, and suprarenals. The medial surface of the right testis has 
been laid bare to show the entrance of the A. testicularis. The left testis has been turned medialward 
to show the terminal branching of the A. spermatica interna on the tunica vaginalis communis and 
between the bundles of the M. cremaster. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 580 
Fig. 9.56.) 



ABDOMEN AND PELVIS 513 

Abdominal Aorta (Aorta abdominalis). (Fig. 271.) 

(a) Parietal branches (rami parietales). 

(aa) Inferior phrenic artery (A. phrenica inferior). 

(aaa) Superior suprarenal branches (rami suprarenales 
superiores). 

(ab) Lumbar arteries (Aa. lumbales). These run behind the 

truncus sympathicus. 

(aba) Dorsal branch (ramus dorsalis). 

(abb) Spinal branch (ramus spinalis). 

(ac) Middle sacral artery (A. sacralis media). 

(aca) Lowest lumbar artery (A. lumbalis ima). 

(acb) Coccygeal skein (glomus coccygeum). 

(b) Visceral branches (rami viscerales). 

(ba) Coeliac artery (A. coeliaca). 

(baa) Left gastric artery (A. gastrica sinistra). 

(bab) Hepatic artery (A. hepatica). 

(bac) Splenic artery (A. lienalis). 

(bb) Superior mesenteric artery (A. mesenterica superior), 
(be) Inferior mesenteric artery (A. mesenterica inferior). 

(bd) Middle suprarenal artery (A. suprarenalis media) (0. T. 

middle capsular artery). 

(be) Renal artery (A. renalis). 

(bea) Inferior suprarenal artery (A. suprarenalis infe- 
rior). 

(bf) Internal spermatic artery (A. spermatica interna). 

(1) Testicular artery ( A. testicularis) (in the male). 

(2) Ovarian artery (A. ovarica) (in the female). 
Notice the levels at which these arteries are given off and their rela- 
tion to the vertebrae. Do you find any evidences of the segmental origin 
of the aorta? 

Inferior Vena Cava (Vena cava inferior). 

(a) Parietal roots (radices parietales). 

(aa) Inferior phrenic vein (V. phrenica inferior). 

(ab) Lumbar veins (Vv. lumbales). 

(b) Visceral roots (radices viscerales). 

(ba) Hepatic veins (Vv. hepaticae). 

(bb) Renal veins (Vv. renales). 

(be) Suprarenal veins (Vv. suprarenales). 

(bd) Spermatic vein (V. spermatica). 

(be) Testicular vein (V. testicularis). 

(bf) Ovarian vein (V. ovarica). 

(bg) Pampiniform plexus (plexus pampiniformis) . 

Note the division of the abdominal aorta into the 

Common Iliac Arteries (Aa. iliacae communes). 

At what level does this bifurcation occur? Note the general 
direction of the artery and its length. What is the relation of 
each common iliac artery to the intestinum tenue, the sympa- 
thetic nerves connecting the plexus aorticus abdominalis, and 

33 



514 LABORATORY MANUAL OF HUMAN ANATOMY 

the plexus hypogastricus and the ureter? What relation does 
the A. haemorrhoidalis superior bear to the artery of the left 
side? Note that the common iliac artery bifurcates below (vide 
Fig. 285) into 

(a) Hypogastric artery (A. hypogastrica) (0. T. internal iliac). The 

branches of this artery will be studied when the pelvis is dissected. 

(b) External iliac artery (A. iliaca externa}. 

(ba) Inferior epigastric artery (A. epigastrica inferior) (0. T. 

deep epigastric). 
(baa) Pubic branch (ramus pubicus). 

(1) Obturator branch (ramus obturatorius) . 
(bob) External spermatic artery (A. spermatica externa) 

(0. T. cremasteric) (in the male). 
(bac) Artery of round ligament (A. Lig. teretis uteri) (in 

the female). 

(bb) Deep circumflex iliac artery (A. circumflexa ilium profunda). 

Common Iliac Veins (Vv. iliacae communes). 

(a) External iliac veins (Vv. iliaca externa). 

(aa) Inferior epigastric vein (V. epigastrica inferior). 

(ab) Deep circumflex iliac vein (V. circumflexa ilium profunda). 

(b) Hypogastric vein (V. hypogastrica) (0. T. internal iliac vein). 

Dissect out at this stage the 
(ba) Iliolumbar vein (V. iliolumbalis). 

The middle sacral vein (V. sacralis media) will be found 
emptying into the left common iliac vein. Other branches of 
the hypogastric vein may be worked out later when the pelvis 
is dissected. 

Lymphatics. 

Dissect out the different lymph-glands; also the lymph- 
trunks (trunci lumbales, truncus intestinalis), which empty into 
the dilated beginning of the ductus thoracicus. This dilatation 
is known as the chyle-cistern (cisterna chyli) (O. T. receptacu- 
lum chyli). (Vide Fig. 249.) Look for it between the aorta 
abdominalis and the crus mediale of the diaphragm on the right 
side. 

Examine the following: 

Lymph-glands. 

(a) Iliac (lymphoglandulae iliacae). 

(b) Coeliac (lymphoglandulae coeliacae). 

(c) Lumbar (lymphoglandulae lumbales). 

Lymph-plexuses. 

(a) External iliac (plexus [lymphaticus] iliacus externus). 



ABDOMEN AND PELVIS 515 

(b) Coeliac (plexus [lymphaticus] coeliacus}. 

(c) Lumbar (plexus [lymphaticus] lumbalis). 

(d) Aortic (plexus [lymphaticus] aorticus). 

Azygos and Hemiazygos Veins (V. azygos and V. hemiazygos). 

Study the abdominal tributaries of these veins. (Cf. Spalte- 
holz, Fig. 495.) Examine especially the ascending lumbar vein 
(V. lumbalis ascendens). 



NEEVES IN THE ABDOMEN. 

Abdominal Part of Sympathetic Trunk (Truncus sympathicus, pars 
abdominalis) . (Vide Toldt, Fig. 1327.) 

Study the position of the truncus sympathicus in the abdo- 
men. Determine its relation to the lumbar vessels and inferior 
vena cava. Examine the lumbar ganglia (ganglia lumbalia). 
Whither do the lateral and medial branches from these ganglia 
go! Review the general disposition of the systema nervorum 
sympathicum. What are the rami communicanles, and in what 
relation do they stand to the spinal nerves ? 

Lumbar Plexus (Plexus lumbalis). (Figs. 272 and 273.) 

Eemove by blunt dissection the M. psoas major and expose 
the lumbar plexus, preserving carefully the nerves derived from 
it. (Cf. Toldt, Fig. 1327.) Study- 

(a) Muscular branches (rami musculares} . 

(b) Iliohypogastric nerve (N. iliohypogastricus). 

(ba) Muscular rami (rami musculares). 

(bb) Lateral cutaneous ramus (R. cutarieus lateralis). 
(be) Anterior cutaneous ramus (R. cutaneus anterior). 

(c) Ilio-inguinal nerve (N. ilio-inguinalis) . 

(ca) Muscular branches (rami musculares). 

(cb) Anterior scrotal nerves (Nn. scrotales anteriores). 
or Anterior labial nerves (Nn. labiales anteriores). 

(d) Genitofemoral nerve (N. genitofemoralis) (0. T. genitocrural). 

(da) Lumbo-inguinal nerve (N. lumbo-inguinalis) (0. T. crural 

branch). 

(db) External spermatic nerve (N. spermaticus externus) (0. T. 

genital branch). 

(e) Lateral cutaneous nerve of thigh (N. cutaneus femoris lateralis) (0. 

T. external cutaneous). 
(/) Obturator nerve (N. obturatorius) . 

(fa) Anterior branch (ramus anterior). 

(fb) Posterior branch (ramus posterior). 



516 



LABORATORY MANUAL OF HUMAN ANATOMY 



FIG. 272. 



Costa XII. 
N. intercostalis XII. 
\ 




M. quadratus lumborum 

Aponeurosis of the M. transversus, 
abdominis 
M. psoas major 

N. iliohypogastricus^ 
N. ilio-inguinalis 



M. obliquus externu 
abdominis 



M, obliquus internus 

abdominis 

N. cutaneus femoris 
lateralis 

Ram us cutaneus lateralis__ 
of the N. iliohypo- 
gastricus 



Ramus cutaneus femoris 
anterior 

Fascia iliopectinea, 
Lig. inguinale (Pouparti)- 

Fascia lata 
Fascia cribrosa- 



V. saphena magna 



Vertebra thoracalis XII 



Truncus sympathicus 



Ganglia trunci sym- 
pathici 



Ramus communicans 
N. genitofemoralis 



N. spermaticus externus 

N. lumbo-inguinalis 
N. obturatorius 

N. femoralis 

A. and V. iliaca externa 

Ductus deferens 

M. pyramidalis 



. suspensorium 
penis 



N. dorsalis penis 



Funiculus spermaticus 
Tunica vaginalis commun 



Scrotum 



The nerves from the plexus lumbalis. (The N. ilio-inguinalis has been cut off just above the anterior 
superior iliac spine. ) (After Toldt, Anat. Atlas, Wien, 1903, 3 AufL, p. 837, Fig. 1273.) 



ABDOMEN AND PELVIS 
FIG. 273. 



517 



Thxii 



Li 1 



ih 



Liii 



Liv 




Siii 



Plexus lumbosacralis, including the plexus lumbalis, the plexus sacralis, and the plexus pudendus. 

Ventral aspect. 

rl, ramus cutaneus lateralis of the N. subcostalis ; ih, N. iliohypogastricus ; ri, its ramus iliacus ; ii, 
N. ilio-inguinalis ; ql, nerve for quadratus lumborum ; se, N. spermaticus externus ; li, N. lumbo-ingui- 
nalis ; p, ramus muscularis to M. psoas ; d, N. cutaneus femoris lateralis ; i, ramus muscularis to M. 
iliacus ; ip, ramus muscularis to M. iliopsoas ; Or, N. femoralis ; oa, N. obturatorius accessorius ; o, N. 
obturatorius ; gs, N. glutaeus superior ; pi, ramus muscularis to M. piriformis ; Pe, N. peronaeus ; gi, N. 
glutaeus inferior ; Ti, N. tibialis ; fi, rami musculares to Mm. flexores cruris ; q, ramus muscularis to M. 
quadratus femoris and M. gemellus inferior; oi, ramus muscularis to M. obturator internus and M. 
gemellus superior ; cp, N. cutaneus femoris posterior ; cm, N. cut. clun. inf. medialis (N. perforans lig. 
tuberoso-sacrum) ; pu, N. pudendus ; h, N. haemorrhoidalis ext. ; I, ramus muscularis to M. levator ani ; 
c, ramus muscularis to M. coccygeus ; a, 6, Nn. anococcygei. (After P. Eisler, taken from Rauber's 
Lehrbuch der Anatomic des Menschen.) 



(g) Femoral nerve (JV. femoralis). 

(ga) Anterior cutaneous branches (rami cutanei anteriores), 

(gb) Muscular branches (rami musculares). 



518 LABORATORY MANUAL OF HUMAN ANATOMY 

(gc) Saphenous nerve (N. saphenus). 

Its branches are studied in the dissection of the lower 
extremity. 

What is the lumbosacral trunk (truncus lumbosacralis) (0. 
T. lumbosacral cord), and what nerves unite to form it? What 
rami anteriores of spinal nerves unite to form the lumbar 
plexus f l 

FASCIA AND MUSCLES. 

Cut through the aorta and vena cava inferior at the level of 
the bifurcation of the aorta. Separate the pelvis from the rest 
of the trunk at the level of the disk between the third and fourth 
lumbar vertebrae. 

Iliac Fascia (Fascia iliaca). (Vide Spalteholz, Fig. 370.) 

Note the relation of .this fascia to the M. iliopsoas, the lumbar 
vertebrae, the crista iliaca, and medially to the pelvic fascia 
(fascia pelvis). Show that these two fasciae are continuous. 
Determine the line of attachment of the fascia to Poupart's liga- 
ment (ligamentum inguinale [Pouparti]) and trace^ it down- 
ward to the eminentia iliopectinea. What are the fascia iliopec- 
tinea, lacuna musculorum and lacuna vasorum? (Vide Fig. 58.) 
What is the relation of this fascia to the femoral vessels! 
Locate at this stage of your dissection the annulus femoralis, 
and, if possible, its septum (septum femorale [Cloqueti] ). From 
what fascia is this septum derived! Dissect out the lymph-nodes 
of Rosenmuller. Determine their exact position and communi- 
cations. Dissect out the fascia covering the M. quadratus lum- 
borum, noting its exact attachments and general disposition. 

Muscles at the Back of the Abdomen. 

Clean the following muscles, noting the exact form, position, 
origin, insertion, action, and innervation of each. Avoid the 
sympathetic cord found medial from the iliopsoas muscle, also 
the nerves of the lumbar plexus, which may be readily seen, and 
take care not to destroy the iliac fascia as it passes into the 
fascia pelvis. 

(a) Quadrate muscle of the loins (M. quadratus lumborum). 

(b) Iliopsoas muscle (M. iliopsoas}. 

(ba) Greater psoas (M. psoas major). 

(bb) Lesser psoas (M. psoas minor), 
(be) Iliac (M. iliacus). 

1 For a statistical study of the variations which occur in this region, see the 
paper by Bardeen and Elting, Anatomischer Anzeiger, 1901, vol. xix. p. 124. 



ABDOMEN AND PELVIS 519 



DISSECTION OF THE MALE PELVIS. 

Before beginning the dissection of the pelvic viscera, review 
the anatomy of the bones entering into the formation of the 
pelvis. Compare the male and female pelves, noting the differ- 
ences in the diameters, angles of inclination, size and general 
structure of the bones. Before disturbing any relations examine 
the position of each viscus. Compare the positions found in 
the adult with tho*se in the child. Note the peritoneal relations 
of each viscus and study the peritoneal folds. 

Peritoneal Folds. (Vide Spalteholz, Fig. 667.) 

(a) Transverse vesical fold (plica vesicalis transversa). 

This fold disappears when the bladder is distended. 

(b) Pubovesical fold (plica pubovesicalis) . 

(c) Rectovesical fold (plica rectovesicalis). 

The rectovesical folds are raised by the obliterated umbilical 
arteries. They form the lateral boundaries of a deep excavation 
between the bladder and the rectum (excavatio rectovesicalis). In 
the folds will be found the rectovesical muscles (Mm. rectovesi- 
cales), which are composed of smooth muscle-fibres derived from 
the walls of the neighboring viscera. 

(d) Mesorectum. A fold of peritoneum connecting the first part of the 

rectum to the posterior wall of the pelvis. 

Hypogastric Plexus (Plexus hypogastricus). (Vide Toldt, Figs. 1331 
and 1333.) 

This sympathetic plexus rests upon the body of the fifth 
lumbar vertebra between the common iliac arteries. Establish 
its relation to the plexus aorticus and the ganglia lumbalia. In- 
feriorly it divides into two parts, which accompany the hypo- 
gastric arteries into the pelvis. Dissect out the plexus, trace it 
downward into the pelvis, and dissect out the following plexuses 
and nerves derived from it : 

(a) Middle hemorrhoidal plexus (plexus haemorrhoidalis medius). 

(b) Prostatic plexus (plexus prostaticus) . 

(c) Deferential plexus (plexus deferentialis). 

(d) Vesical plexus (plexus vesicalis). 

(da) Superior vesical nerves (Nn. vesicales superiores). 

(db) Inferior vesical nerves (Nn. vesicales inferiores). 

(e) Cavernous plexus of penis (plexus cavernosus penis). 

(ea) Greater cavernous nerve of penis (N. cavernosus penis 

major). 

(eb) Lesser cavernous nerves of penis (Nn. cavernosi penis 

minores). 



520 



LABORATORY MANUAL OF HUMAN ANATOMY 



Pelvic Fascia (Fascia pelvis). (Vide Spalteholz, Fig. 677.) 

The lower aperture of the pelvis is closed by the pelvic dia- 
phragm, which consists mainly of the M. levator ani with a layer 
of fascia above it and another beneath it. 

The inferior fascia of the pelvic diaphragm (fascia dia- 
phragmatis pelvis inferior) has already been studied in the dis- 
section of the ischiorectal fossa, and its relation to the obturator 
fascia (fascia obturatoria) and the arcus tendineus M. levatoris 



FIG. 274. 




To show the lines of the saw-cuts to remove the part of the os coxae bearing the acetabulum to expose 
the external surface of the fascia pelvis by Cunningham's method. 

ani (0. T. white line of the pelvis *) established. The white line 
of the pelvis may be exposed from the external side by removing 
the acetabular part of the os coxae by saw-cuts (Pigs. 274, 275). 

'The German anatomists have misapplied the term "white line of the 
pelvic fascia" to the arcus tendineus fasciae pelvis. 



ABDOMEN AND PELVIS 521 

To expose the superior fascia of the pelvic diaphragm (fascia 
diaphragmatis pelvis superior), remove the peritoneum from 
the sides of the pelvic wall and bladder by blunt dissection. 
Scrape away carefully the extraperitoneal fatty tissue with the 
handle of the scalpel. The bladder must be forcibly separated 
from the pubic bones and the intervening fatty tissue removed, 
to secure adequate exposure of the fascia anteriorly. 

After the fascia has been exposed establish its continuity 

FIG. 275. 




To show the cut surfaces of the os coxae after removal of the piece cut out to expose the external 

surface of the pelvic fascia. 

with the fascia transversalis and the fascia iliaca at the terminal 
line (linea terminalis). Trace it downward and demonstrate 
that it covers the ilium and the upper part of the fascia obtura- 
toria. It then becomes thickened and passes downward and 
medialward upon the upper surface of the pelvic diaphragm as 
far as the tendinous arch of the pelvic fascia (arcus tendineus 
fasciae pelvis) ; the tendinous arch passes in a curve, convexity 
directed downward and lateralward, from the symphysis ossium 



522 LABORATORY MANUAL OF HUMAN ANATOMY 

FIG. 276. 




Fascia 
obturatoria' 



Fascia en do 
pel vina 

Fasc. endopelv.. 
Fasc. diaph. pelvis sup. 
Fasc. diaph. pelvis inf.- 
Fasc. obturatoria 

Fibro-elastic network of 
the int. rect. and diaph. 
pelv. which passes through 
the M. sph. ani ext. to end" 
in the skin around the 
anus 



Vesicula 
" seminalis 
Venous plexus 

M. obt. int. 



-Diaphragma pelvis 

-Fossa cav. ischio rect 
M. sph. ani int. prof. 
M. sph. ani ext. superf. . 



N. sph. ani ext. subcut. 

Diagram of the pelvic fasciae as seen in a frontal section of the pelvis passing through the rectum. 
(After Holl, in Handb. der Anat. des Mensch. von Bardeleben, Jena, 1896, Bd. vii., T. 2, Abt. 1, p. 162, 
Fig.l.) 

FlG. 277. 




Fasc, 
obtur. 



Fasc. diaph. . 
pelv. sup. 

*Fasc. endopelv. 
Fasc. diaph. pelv. sup. 

Fasc. diaph. pelv. inf. -- 
Fasc. diaph. urogen. inf. 

Fasc. of the M. ischiocav. 
Fasc. of the M. bulbocav. 




M. obt. int. 



Diaph. pelvis 
Venous plexus 
Venous plexus 

Venous plexus 
Diaph. urogen. 
M. bulbocav. 



-/ .M. ischiocav. 



Diagram of the pelvic fasciae shown in a frontal section through the urogenital region. (After Holl, in 
Handb. der Anat. des Mensch. von Bardeleben, Jena, 1896, Bd. 7, T. 2, Abt. 1, p. 163, Fig. 2. ) 



ABDOMEN AND PELVIS 



523 



pubis to the spina ischiadica. Demonstrate that medialward 
from the arcus tendineus fasciae pelvis the greater part of the 
fascia is reflected upon the viscera (urinary bladder and rectum) 
and venous plexuses about them as the endopelvic fascia 
(fascia endopelvina) , and that other strands of fascia follow the 
medial surface of the levator as far as the prostate, where they 
fuse with the capsule of the latter organ, sometimes called the 
fascia prostatae. English writers describe the fascia endopel- 
vina as consisting of three layers, (1) vesical, (2) rectovesical, 
and (3) rectal. 

FIG. 278. 



Fascia endopelv 

Fasc. diaph. pelv. sup. 

Fasc. diaph. pelvis inf. 

Fasc. obt. 
Memb. obt. 



. ..J...YOSS& formed by the fascia pelvis 



-Venous plexus 
Prostata 



Vesic. sem. 




Fascia 

recto- 

vesicalis 



M. obt. int. 

Diaph. 
pelvis 



Lig. sacro 

tub. 



Diagram of the fasciae of the pelvis shown in a horizontal section of the pelvis. The fascia vesic. 
sem., fascia rectovesiea, and fasria nvti prop, are parts of the fascia endoprlvina. (After Holl, in 
Handb. der Anat. des Menscli. von Bardeleben, Jena, 18%, Bd. vii., T. 2, Abt. 2, p. 285, Fig. 34.) 

Demonstrate that the fascia descends deeper between the an- 
terior ends of the two arcus tendinei fasciae pelvis and forms a 
small fossa. (Cf. Fig. 279.) Isolate the prominent bands bound- 
ing this fossa laterally, the lateral puboprostatic ligaments 
(Ligg. puboprostatic a later alia] (0. T. lateral true ligaments of 
the bladder) ; in the female they are the /,/////. pubovesicalia Inf- 
er alia (0. T. vesical layer of fascia endopelvina). Dissect in the 



524 



LABORATORY MANUAL OF HUMAN ANATOMY 



depth of the fossa, and expose the middle puboprostatic ligament 
(Lig. puboprostaticum medium) (0. T. anterior true ligament 
of bladder) ; in the female it is called the middle pubovesical 
ligament (Lig. pubovesicale medium). 

Where are the pubovesical muscles (Mm. pubovesicales) to 
be found, and from what are they derived? What relations do 
the vessels and nerves of the pelvis bear to the pelvic fascia? 

Rectum (Intestinum rectum). (Vide Spalteholz, Fig. 575.) 

Determine the extent, general direction, and peritoneal rela- 
tions of the rectum. Supplement the dissection by the use of 



FIG. 279. 



Ureter dexter 
Ductus deferens 



Fundus vesicae VwCv 



Vesicula seminalis 
dextra 



Intestinum. 
rectum 



Prostata U 



M. sphincter, 
ani ex tern us 



Lig. umbilicale medium 



Vertex vesicae 



Corpus vesicae 

Lig. puboprostaticum (pubo- 
/ vesicale) medium 

Symphysis ossium 
pubis 




M. pubovesicalis 
M. obturator internus 
Fascia diaphragmatis pelvis superior 



. levator ani 
Ramus inferior ossis ischii 



The stratum externum of the tunica muscularis of the urinary bladder, and the relations of the 
seminal vesicles and prostate to the bladder and rectum. Seen from the right side. (The prostate is 
abnormally enlarged.) (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 481, Fig. 812.) 

models and cross-sections. Compare the external markings of 
the rectum with those of the colon, noting carefully any differ- 
ences. Establish the position of the following : 

(a) Flexures: 

(aa) Sacral flexure (flexura sacralis). 

(ab) Perineal flexure (flexura perinealis). 

(b) Ampulla of rectum (ampulla recti). 



ABDOMEN AND PELVIS 525 

This ampulla is the ovoid enlargement in the lower part of 
the rectum, and serves as a reservoir for faeces. It is sometimes 
spoken of as the " faecal bladder/' Note the curves in the 
frontal direction, produced by lateral furrows, which correspond 
to the transverse folds of the rectum (plicae transversales recti). 
What is the rectococcygeal muscle (M. rectococcygeus) ? The 
rectum will be opened and its interior studied later. 

Urinary Bladder (Vesica urinaria). (Vide Figs. 279, 281, and Spalte- 
holz, Figs. 641, 642.) 

Examine the position and form (Fig. 280) of the bladder. To 
complete this study make use of models and cross-sections. How 
do the position and form of the bladder differ in the two sexes? 
How does the adult bladder differ in position and form from that 
of the child? From what does the bladder develop embryologi- 
cally? (Cf. Kollmann, Lehrbuch der Entwickelungsgeschichte 
des Menschen, p. 348.) Study the following features: 

(a) Apex of bladder (apex vesicae). 

(b) Body of bladder (corpus vesicae). 

(c) Fundus of bladder (fundus vesicae). 

(d) Neck of bladder (collum vesicae). 

What is the urachus f 

Pelvic Part of Ureter (Pars pelvina ureteris). (Vide Spalteholz, Figs. 
640, 641). 

Isolate the ureter as it enters the pelvis at the bifurcation of 
the common iliac artery and trace it downward to the bladder. 
Determine its relation to the plica rectovesicalis. What are the 
relative positions of the obliterated hypogastric artery and the 
ureter in this plica? As the ureter is traced forward, determine 
its relations to the ductus deferens and the vesicula seminalis. 
At what angle does it pierce the bladder wall? 

Prostate (Prostata). (Vide Figs. 227, 279, and Spalteholz, Figs. 640, 
643> 653, 655, 656, 677.) 

Note the general size, shape, and position of this organ. 
Determine its relations to the neighboring structures. Keview 
the anatomy of the capsule of the prostate. Avoiding injury to 
the venous plexus surrounding the organ, study the following: 

Lobes. 

(a) Right lobe (lobus dexter). 

(b) Left lobe (lobus sinister). 



526 



LABORATORY MANUAL OF HUMAN ANATOMY 



(c) Middle lobe (lobus medius). 

The latter lobe is not always present. To bring it into view, if 
present, separate the seminal vesicles and the vasa deferentia 

FIG. 280. 




Schema showing the modifications in the form of the bladder during repletion. (From Poirier et 
Charpy, Traite" d Anat. hum., Paris, 1901, t. v. p. 79, Fig. 63.) 

from the base of the bladder and throw them backward. Many 
authorities maintain that this lobe is to be found only in patho- 
logical cases. 



M. obturator 
intemus 

Tela subserosa^J 



Cross-section of 
the arcus ten- 
dineus fasciae x 
pelvis 

Fascia 
endopelvina - 

M. obturator, 
internus 



Fascia obturatoria 

Fascia diaphragma- ... 
tis pelvis superior 

M. levator ani - 
Fascia prostata 



M. ischiocavernosus " / 

M. transversus perinei superficialis 



FIG. 281. 

Ampulla ductus deferentis 



Spina iliaca poste- 
rior inferior 

Plexus (venoms) 
pudendalis 

Incisura ischiadica- 
major 

---Fpina ischiadica 




- Fascia obturatoria 



..-Fascia diaphragmatis 
pelvis inferior 

...Prostata (facies 
posterior) 

A. pudenda interna 



"" Tuber ischiadicum 



Fascia diaphragmatis urogenitalis superior 
M. bulbocavernosus 



The position of the seminal vesicles and ampullae of the ductus deferentes in relation to the fundus 
of the bladder and to the prostate. The M. levator ani has been cut across in a frontal plane. The 
fascia prostatae has been removed on the right side ; on the left side its upper part, passing on to the 
seminal vesicle, has been loosened and turned down. Seen from behind. (After Toldt, Anat. Atlas, 
Wien, 1900, 2 Aufl., p. 516, Fig. 895.) 



Surfaces. 

(a) Anterior surface (facies anterior}. 
(&) Posterior surface (facies posterior). 



ABDOMEN AND PELVIS 



527 



Examine further 

(a) Base of prostate (basis prostatae). 

(b) Apex of prostate (apex prostatae). 

(c) Isthmus of prostate (isthmus prostatae). 

Seminal Vesicles (Vesiculae seminales). (Vide Figs. 281, 282, and 
Spalteholz, Figs. 599, 640, 653, 654.) 

Note the general shape of the seminal vesicles ; also the gen- 
eral direction of their long axes. Determine their relations to 
the prostate, the fundus and neck of the bladder, the ampulla 
of the deferential duct, and the ureter. Examine the body of the 
seminal vesicle (corpus vesiculae seminalis) and its excretory 
duct (ductus excretorius). With what structure does the ductus 
excretorius join below? 

FIG. 282. 



Ductus deferens \ 



Corpus vejsiculae seminalis 




Ampulla ductus deferentis 



Ductus excretorius vesiculae seminalis 



Ductus ejaculatorius 



Longitudinal section through the right seminal vesicle. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl. 

p. 488, Fig. 829.) 

Deferent Duct (Ductus deferens) (O. T. Vas deferens). (Vide 
Spalteholz, Figs. 599, 633, 640, 653, 654, 656.) 

Trace the ductus deferens from the annulus inguinalis ab- 
dominalis downward into the pelvis. Determine again its rela- 
tion to the A. et V. epigastrica, the A. et V. iliaca externa, and the 



528 



LABORATORY MANUAL OF HUMAN ANATOMY 



vessels and nerves of the lateral pelvic wall. Note the spindle- 
shaped dilatation or ampulla (ampulla ductus defer entis] behind 
the bladder. Observe the diverticula (diverticula ampullae}. 
With what structure does the ampulla communicate! What duct 
is formed by this communication? Open the ampulla and dissect 
its wall. Study 

(a) Adventitious coat (tunica adventitia). 

(b) Muscular coat (tunica muscularis}. 

(ba) External, middle, internal layer (stratum externum, medium, 
internum). 

(c) Mucous coat (tunica mucosa). 



ARTERIES OF PELVIS. 

Carefully clean each vessel and its branches. Study its 
course and relations. Before beginning the dissection, remove 



FIG. 283. 



A. acetabuli ^^JL 



Memb. obt. ext... 

Ram. intrapelv. //' 

(Waldeyer) 
Posterior branch - 




A. obturatoria 

Ram. prepubicus 
Anterior branch 



The obturator artery. (From Poirier et Charpy, Traite d'Anat. hum., Paris, 1901, 2 ed, t. ii. p. 802, 

Fig. 440.) 

the cotton from the rectum, and if the bladder is still distended 
allow the air to escape. Preserve the sympathetic twigs follow- 
ing each artery. 



ABDOMEN AND PELVIS 529 

Hypogastric Artery (A. hypogastrica) (O. T. Internal Iliac Artery). 
(Vide Fig. 285, and Spalteholz, Figs. 470, 471.) 

Read an account of the foetal circulation before dissecting 
out this artery. Note the differences between the adult and the 
foetus. 

Parietal Branches (Rami parietales). 

(a) Iliolumbar artery (A. iliolumbalis). 

(aa) Lumbar branch (ramus lumbalis). 

(ab) Spinal branch (ramus spinalis). 

(ac) Iliac branch (ramus iliacus). 

(b) Lateral sacral artery (A. sacralis lateralis). 

(ba) Spinal branches (rami spinales). 

(c) Obturator artery (A. obturatoria) . (Figs. 283-285.) 

(ca) Pubic branch (ramus pubicus). 

(cb) Anterior branch (ramus anterior). 

(cc) Posterior branch (ramus posterior). 

(cd) Artery of the acetabulum (A. acetabuli). 

(d) Superior gluteal artery (A. glutaea superior). 

(da) Superior branch (ramus superior). 

(db) Inferior branch (ramus inferior). 

(e) Inferior gluteal artery (A. glutaea inferior). 

(ea) Companion artery of sciatic nerve (A comitans N. ischia- 
dici). 

Visceral Branches (Rami viscerales). 

(a) Umbilical artery (A. umbilicalis) . 

(aa) Superior vesical arteries (Aa. vesicales superiores). 
[Ligamentum umbilicale laterale]. 

(b) Inferior vesical artery (A. vesicalis inferior). 

(c) Deferential artery (A. deferentialis). 

(d) Uterine artery (A. uterina) (in the female). 

(da) Vaginal artery (A. vaginalis). 

(db) Ovarian branch (ramus ovarii). 

(dc) Tubal branch (ramus tubarius). 

(e) Middle hemorrhoidal artery (A. haemorrhoidalis media). 

(f) Internal pudendal artery (A. pudenda interna). 

The branches of this artery have already been met 
with in earlier dissections, but are repeated here for 
review. 

(fa) Inferior hemorrhoidal artery (A. haemorrhoidalis infe- 

rior). 

(fb) Artery of perineum (A. perinei). 

(fba) Posterior scrotal arteries (Aa. scrotales poste- 

rior es} (in the male). 

(fbb) Posterior labial arteries (Aa. labiales posteriores) 

(in the female). 

(fc) Artery of penis (A. penis) (in the male). 

(fca) Urethral artery (A. urethralis). 

(fcb) Artery of the bulb of urethra (A. bulbi urethrae). 
(fee) Deep artery of penis (A. profunda penis). 

34 



530 LABORATORY MANUAL OF HUMAN ANATOMY 



FIG. 284. 







Schema showing the different ways in which the A. obturatoria may arise. (From Poirier et 
Charpy, Traits' d'Anat. hum., Paris, 1901, 2 ed., t. ii. p. 801, Fig. 441.) 



ABDOMEN AND PELVIS 



531 



(fed] Dorsal artery of penis (A. dorsalis penis), 
(fd) Artery of clitoris (A. clitoridis) (in the female). 

(fda) Artery of vestibular bulb of vagina (A. bulbi ves- 
tibuli [vaginae]). 

FIG. 285. 



A. iliaca ext. - - 



A. umbilicalis - 

'A 

V > ' ' (R 

A. vesicalis inf. 

; \ 

A. defcrentialis A 
et A. haemor- r ' 
rhoidajis med. \ 



Pudendo- 

obturator 

anastomosis 



Ram. prepubic 
A. prof, penis 



Aa. dorsales f 

penis (dextra-{ 

et sinistra) I 



A. urethral 




A. iliaca com. 



A. iliolumbalis 
A. sac. lat. sup. 

A. sac. lat. 

A. glutaea sup. 



A. glutaea inf. 



A. obturatoria 



A. pudenda 
interna 



A. haem. inf. 



A. bulbo-urethrae (dextra) 



A. bulbo-urethrae 
(sinistra) 

Aa. scrotales 
posteriores 



The A. pudenda interna. (From Poirier et Charpy, Traits d'Anat. hum., Paris, 1901, 2 ed., t. ii. p. 

Fig. 442.) 



(fdb) Urethral artery (A. urethralis). 

(fdc) Deep artery of clitoris (A. clitoridis). 

(fdd) Dorsal artery of clitoris (A. dorsalis clitoridis), 



532 LABORATORY MANUAL OF HUMAN ANATOMY 

Superior Hemorrhoidal Artery (A. haemorrhoidalis superior). (Vide 

Fig. 286, and Spalteholz, Fig. 470.) 

Trace this artery down into the mesorectum. What course 
does it pursue below, and how does it end in the rectal wall? 



FIG. 286. 




_V. haemorrhoidalis superior 



A. haemorrhoidalis superior 



A., haemorrhoidalis 
media 



A. haemorrhoidalis inferior 



The arteries and veins of the rectum and anus. Their disposition upon the periphery of the posterior 
wall. (From Poirier et Charpy, Trait6 d'Anat. hum., Paris, 1901, 2 ed., t. iv. p. 389, Fig. 200.) 

Middle Sacral Artery (A. sacralis media). 

(a) Lowest lumbar artery (A. lumbalis ima). 

(b) Coccygeal skein (glomus coccygeum). 



ABDOMEN AND PELVIS 533 

VEINS OF THE PELVIS. 

Study the following: 

Hypogastric Vein (V. hypogastrica). (Vide Spalteholz, Figs. 500, 

50I-) 

Many of the veins which are radicles of the vena hypogas- 
trica have been met with in early dissections. They may be 
reviewed to advantage : 

(a) Internal pudendal vein (V. pudenda interna). 

(aa) Deep veins of penis (Vv. profundae penis). 

(ab) Urethral veins (Vv. urethrales). 

(ac) Veins of bulb of urethra (Vv. bulbi urethrae). 

(ad) Posterior scrotal veins (Vv. scrotales posteriores) . 
In the female : 

(ae) Inferior hemorrhoidal veins (Vv. haemorrhoidales inferiores). 

(af) Deep veins of clitoris (Vv. profundae clitoridis). 

(ag) Veins of bulb of vestibule of vagina (Vv. bulbi vestibuli 

[vaginae]), 
(ah) Posterior labial veins (Vv. labiales posteriores). 

(b) Internal hemorrhoidal plexus (plexus haemorrhoidalis internus) f 

which will be seen in the dissection of the rectal wall. The veins 
pierce the rectal wall and form the external hemorrhoidal plexus 
(plexus haemorrhoidalis externus). What veins arise from this 
latter plexus, and into what larger veins do they empty? 

(c) Vesical plexus (plexus vesicalis). (Vide Spalteholz, Figs. 500, 503, 

677.) 

Determine the relation of this plexus to the bladder and to the 
prostate. By what veins is it drained? 

(d) Pudendal plexus (plexus pudendalis). 

What is the relation of the dorsal vein of the penis to this 
plexus? What course must this vein pursue to reach it? 

(e) Utero vaginal plexus (plexus uterovaginalis) . 

Middle Sacral Vein (V. sacralis media). 

Determine its relation to the Vv. sacrales laterales. What is 
the anterior sacral plexus (plexus sacralis anterior) ? 



MUSCLES AND NERVES OF THE PELVIS. 

Muscles of the Pelvic Diaphragm. (Vide Fig. 287, and Spalteholz, 

Figs. 670, 671.) 

Clean away all that remains of the fascia diaphragmatis 
pelvis superior and study the muscles of the pelvic diaphragm. 
In cleaning the coccygeus muscles avoid injury to the fifth sacral 



534 



LABORATORY MANUAL OF HUMAN ANATOMY 



and coccygeal nerves. Supplement the dissection by use of 
models and moist preparations. Compare the arrangement of 
the muscles in the two sexes. Study comparative preparations 
of the dog pelvis from the museum, and note how homologous 
muscles are related to the tail. 

(a) Levator ani muscle ("elevator muscle of the anus") (M. levator ani). 

(aa) Pubococcygeus muscle (M. pubococcygeus). 

(ab) Iliococcygeus muscle (M. iliococcygeus). 

(b) Coccygeus muscle (M. coccygeus). 

Are the anterior and posterior sacrococcygeus muscles present in your 
subject? 

FIG. 287. 



M. sacrococcygeus anterior 



Aponeurosis of the pars pubica of 
the M. levator ani 

M. coccygeus 
M. rectococcygeus 



. Vertebra sacralis II. 
Lig. sacrotuberosum 



sacrococcygeum anterius 
M. obturator interims 
Fascia obturatoria 




\Canalis obtuatorius 
Intestinum rectum 
Rarm 



Arcus tendineus 
M. levatoris ani 

M. levator ( Parsillaca 
ani \Pars pubica 



The levator ani and coccygeus muscles, seen from above. The hip-bones have been pulled apart after 
splitting the symphysis ossium pubis. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 514, Fig. 891.) 

Pelvic Spinal Nerves. (Vide Toldt, Fig. 1295.) 

Determine the number of nerves entering into the formation 
of each of the following plexuses. Are the plexuses formed by 
the anterior or posterior primary divisions of spinal nerves! 
Trace each nerve as far as possible, noting course and distribu- 
tion. Make a drawing of the plexuses and determine the gen- 
eral plan of their formation. 

(a) Sacral plexus (plexus sacralis). 

(aa) Superior gluteal nerve (N. glutaeus superior). 

(ab) Inferior gluteal nerve (N. glutaeus inferior). 



ABDOMEN AND PELVIS 535 

(ac) Posterior cutaneous nerve of thigh (TV. cutaneus femoris pos- 

terior). 

(aca) Inferior nerves of buttocks (Nn. clunium infe- 

riores ) . 

(acb) Perineal branches (rami perineales). 

(ad) Sciatic nerve (N. ischiadicus) . 

(ada) Muscular branches (rami musculares). 

(adb) Common peroneal nerve (N. peronaeus communis). 

(adba) Muscular branches (rami musculares). 
(b) Pudendal plexus (plexus pudendus). 

(ba) Middle hemorrhoidal nerves (Nn. haemorrhoidales medii). 

(bb) Inferior vesical nerves (Nn. vesicales inferiores). 
(be) Vaginal nerves (Nn. vaginales) (in the female). 

(bd) Pudendal nerve (N. pudendus). 

(bda) Inferior hemorrhoidal nerves (Nn. haemorrhoidales 

inferiores). 

(bdb) Nerve of perineum (N. perinei). 

(bdc) Posterior scrotal or labial nerves (Nn. scrotales vel 

labiales posteriores) . 

(bdd) Dorsal nerve of penis or of clitoris (N. dorsalis 

penis vel clitoridis). 

(be) Coccygeal nerve (N. coccygeus}. 

(bea) Anococcygeal nerves (Nn. anococcygei). 

Sacral Part of Sympathetic (Sy sterna sympathicum, pars pelvina). 
(Vide Toldt, Fig. 1327.) 

Determine the number of sacral ganglia (ganglia sacralia) 
and their relation to the sacral foramina. What is the relation 
of the sacral division of the sympathetic trunk to the lumbar 
division! What is the unpaired ganglion (ganglion impar)* 
Determine the distribution of fibres given off from this part of 
the sacral trunk. 

Removal of the Pelvic Viscera. 

Divide the vessels and nerves which are connected with the 
viscera, also the M. levator ani and the puboprostatic ligaments. 
Free the membranous portion of the urethra from the pubic 
arch, avoiding any injury to the urethral walls. Dissect the 
urethra away from the coccyx and remove the viscera. 

Pelvic Muscles. 

Study now the form, position, origin, insertion, action, and 
innervation of the following muscles. (Vide Spalteholz, Fig. ' 
373.) 

(a) Internal obturator muscle (M. obturator internus). 

(b) Piriform muscle (M. piriformis). 



536 



LABORATORY MANUAL OF HUMAN ANATOMY 



PELVIC VISCERA. 

Rectum (Intestinum rectum). 

Dissect the rectum away from the bladder and the prostate. 
Open the rectum along its anterior wall, pin it down upon a 
cork dissecting-tray, and study its coats. (Cf. Fig. 288.) 

(a) Mucous membrane (tunica mucosa). (Vide Spalteholz, Fig. 576.) 

(aa) Transverse rectal folds (plicae transversales recti) (0. T. 
valves of Houston). 

How many do you find? Where is each situated? What 
is the relation of the folds to the tela submucosa and the 
muscular wall of the rectum? 
Lymphatic nodules (noduli lympliatici}. 



(ab) 



Plica transversalis rectU. 

M. sphincter ani tertius 

Tunica mucosa -: 

(Stratum longi-.___ 
tudinale 
Stratum circu- 
lare 

Columnae rectales (Morgagnii).^ 

Sinus rectales.,, 

M. sphincter ani externus<:I 
M. sphincter ani mternus 



FlG. 288. 




Noduli lym- 

phatici soli- 

tarii 



Plicae mu- 
cosae 



-'Pars analis recti 



. Annulus haem- 
orrhoidalis 

~~Integumentum com- 



The tunica mucosa of the lower part of the intestinum rectum and its transition into the integu- 
mentum commune. (After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 429, Fig. 712.) 

In the anal part of the rectum (pars analis recti) study 

(ac) Rectal columns of Morgagni (columnae rectales [Mor- 

gagnii]). 

(ad) Rectal sinuses (sinus rectales). 

(ae) Hemorrhoidal ring (annulus haemorrhoidalis) . 

(b) Submucous tela (tela submucosa). 

(c) Muscular coat (tunica muscularis). 

(ca) Longitudinal layer (stratum longitudinale) . 

(caa) Rectococcygeus muscle (M. rectococcygeus). 

(cb) Circular layer (stratum circulare). 

Note that the fibres of the circular layer are in- 
creased in number in the base of each of the 
transverse rectal plicae. 

(cba) Internal sphincter muscle of anus (M. sphincter ani 
internus}. 



ABDOMEN AND PELVIS 537 

Compare the general structure of the rectum with that of the 
colon, noting any differences. 

Urinary Bladder (Vesica urinaria). (Vide Spalteholz, Figs. 640- 

642.) 

Distend the bladder with air by a bicycle-pump before the 
dissection of its wall is made. Study the layers. 

(a) Serous tunic (tunica serosa). 

(aa) Transverse vesical fold (plica vesicalis transversa), when the 
bladder is empty. 

(b) Muscular coat (tunica muscularis). 

(ba) External layer (stratum externum). 

(baa) Pubovesical muscle (M. pubovesicalis). 

(bab) Rectovesical muscle (M. rectovesicalis) . 

(bb) Middle layer (stratum medium). 

(bba) Sphincter muscle of bladder (M. sphincter ure- 
thrae). 

What is the relation of this latter to the pros- 
tatic muscle (M. prostaticus) 1 
(be) Internal layer (stratum internum). 

(c) Submucous tela (tela submucosa). 

The mucous membrane of the bladder may be seen to the best 
advantage if the bladder is opened along the anterior surface from 
the apex to the neck. The incision should be made in the median 
line and the urethra opened up along its whole length, to the 
external urethral orifice. (See Fig. 289.) 

(d) Mucous membrane (tunica mucosa). 

Note that when the bladder is empty or only partially 
distended the mucous membrane is thrown into folds. 
Study the following: 

(da) Vesical lymph-nodules (noduli lymphatici vesicales). 

(db) Lieutaud's trigone of the bladder (trigonum vesicae [Lieu- 

taudi\ ) . 

(dba) Vesical uvula (uvula vesicae). 

(dbb) Ureteral fold (plica ureterica). 

(dbc) Orifice of ureter (oriftcium ureteris). 

Pass a probe through the ureter into the bladder 
and note the angle at which it pierces the bladder 
wall. Why does urine not pass from the bladder 
back through the ureter? 

(dc) Internal orifice of urethra (orificium urethrae internum). 

(dd) Urethral ring (annulus urethralis). 

Raise carefully the mucous membrane covering the trigone 
and note the muscular tissue in the folds which bound it. 

The penis should now be pinned down upon a block or a dis- 
secting-tray and the mucous membrane of the different divisions 
of the urethra examined. 



538 LABORATORY MANUAL OF HUMAN ANATOMY 



FIG. 289. 



Annulus urethralis 



Pars prostatica urethrae 



Pars membranacea urethrae 



Pars cavernosa urethrae 



Glans penis - 



Orificium urethrae externunr 




Orista urethralis 
-Colliculus seminalis 
Utriculus prostaticus 
--Opening of the ductus ejaculatorius 
Crista urethralis 

Bulbus urethrae 
~Crus penis 



"Opening of the ductus excre- 

torius glandulae bulbo- 

urethralis 



Septum penis 

Arteria prqfunda penis 
Tunica albuginea 
Corpus cavernosum penis 

Corpus cavernosum urethrae 
-=*> Lacunae urethrales (Morgagnii) 



Fossa navicularis urethrae 

(Morgagnii) 



The male urethra, urethra virilis, laid open by a sagittal incision beside the septum penis. 
(After Toldt, Anat. Atlas, Wien, 1900, 2 Aufl., p. 490, Fig. 835.)' 



ABDOMEN AND PELVIS 539 

Male Urethra (Urethra virilis). 

Review at this stage of your dissection the general direction 
of the urethral canal, also the variations in the diameter of its 
lumen in different parts. Study the following (Fig. 289) : 

(a) Prostatic part (pars prostatica). (Vide Spalteholz, Fig. 643.) 

(aa) Urethral crest (crista urethralis). 

(ab) Seminal hillock (colliculus seminalis). 

(ac) Prostatic utricle (utriculus prostaticus). 

Pass a probe into the prostatic utricle and determine its 
length. What is its homologue in the female? It is of 
importance surgically, as it may render difficult the passing 
of a small sound or bougie and may harbor infection. 

(ad) Mouth of ejaculatory ducts. 

Pass a bristle into the duct and determine its general 
course and direction. 

(ae) Prostatic ducts (ductus prostatici). 

Squeeze the prostate. The fluid that exudes is the pros- 
tatic juice (succus prostaticus). 

(af) Prostatic muscle (M. prostaticus). 

(b) Membranous part (pars membranacea) . 

Note the fixity of this part, also the narrowness of the lumen. It 
is the portion most frequently ruptured. Being the narrowest part 
of the urethra, it is also the most frequently involved in stricture. 

(c) Cavernous part (pars cavernosa). 

(ca) Navicular fossa of urethra (fossa navicularis urethrae [Mor- 

gagnii] ) . 

(cb) Valve of navicular fossa (valvula fossae navicularis). 

(cc) External urethral orifice (orificium urethrae externum). 

(cd) Urethral lacunae of Morgagni (lacunae urethrales [Mor- 

gagnii]). 

(ce) Urethral glands of Littre (glandulae urethrales [Littrei]). 

To complete this study the student should examine sections 
of the prostate and penis under the dissecting microscope. 

Wall of the Seminal Vesicle. (Vide Spalteholz, Fig. 653.) 

Straighten out the seminal vesicles and study the following 
coats : 

(a) Adventitious coat (tunica adventitia). 

(b) Muscular coat (tunica muscularis). 

(c) Mucous coat (tunica mucosa). 



540 



LABORATORY MANUAL OF HUMAN ANATOMY 



DISSECTION OF THE FEMALE PELVIS. 

Before beginning this dissection review the anatomy of the 
bony pelvis. Compare the male and female pelvis, noting differ- 
ences as regards pelvic diameters and the size and general 
structure of the bones. What is the meaning of the terms 
dolichopelvic, mesatipelvic, and platypelvic ? What is the ' ' pel- 
vic index ' ' and how is it estimated ? 



FIG. 290. 



Ampulla tubae uterinae ----- ~ A 
Infundibulum tubae uterinae - 

Fimbriae tubae uterinae^- _ 

Margo liber ovarii-^. 
Facies medialis ovarii . 

Margo mesovaricus - 
Lig. ovarii proprium^ 
Extremitas uterina ovarii _. 

Facies intestinalis uteri 

Plica recto-uterina 
(Douglasi) 

Orificium internum uteri -, 
Canalis cervicis uteri -..,_ 

Excavatio vesico-.. 
uterina 

Fornix vaginae . 

Labium posterius 
Excavatio recto-uterina-' 
Orificium externum uteri 

Labium anterius 



/ Paries anterior 
t Paries posterior 




Lig. suspensorium ovarii 
Extremitas tubaria ovarii 
Bursa ovarica 



Mesosalpinx 

Mesovarium 

, r 
, Isthmus tubae uterinae 

Fundus uteri 
,,.Facies vesicalis uteri 

--Cavum uteri 

Peritonaeum viscerale 



''-%$ Vesica urinaria 
^ Orificium urethrae internum 
1 Urethra 



The genital organs of a girl ten years old, in median section. Left side. (After Toldt, Anat. Atlas, 
Wien, 1900, 2 Aufl., p. 495, Fig. 846.) 

Before disturbing any relations establish exactly the position 
of each viscus. What is the relation of the body of the uterus 
to the bladder and to the rectum? Is the body of the uterus 
flexed upon the neck of the uterus? Make frequent use of 
models, cross-sections, and moist preparations in the further 
study of these parts. 



ABDOMEN AND PELVIS 541 

Peritoneum of Female Pelvis. (Vide Figs. 290, 292, and Spalteholz, 
Fig. 667.) 

Trace the reflections of the peritoneum in the female pelvis. 
Establish the relations of the peritoneum to each viscus and the 
pelvic wall, noting 

(a) Vesico-uterine excavation (excavatio vesico-uterina) . 

(b) Recto-uterine excavation (excavatio recto-uterina) . 

(c) Recto-uterine folds of Douglas (plicae recto-uterinae [Douglasi]). 

(d) Broad ligament of uterus (ligamentum latum uteri). 

(da) Mesometrium (mesometrium) . 

(db) Mesosalpinx (mesosalpinx) . 

(dc) Mesovarium (mesovarium). 

What structures are contained between the two layers of the 
broad ligaments? 

(e) Suspensory ligament of ovary (Lig. suspensorium ovarii). 

Feel this ligament. Do you feel any vessels in it? If so, what 
vessels are they? 

Hypogastric Plexus (Plexus hypogastricus) . (Vide Toldt, Fig. 

I333-) 

This plexus is similar to the one in the male. Refer to the 
pages on the male pelvis for directions as to dissection. The 
following additional plexuses are found in the female : 

(a) Uterovaginal plexus (plexus uterovaginalis) . 

(b) Cavernous plexus of clitoris (plexus cavernosus clitoridis). 

(ba) Greater cavernous nerve of clitoris (N. cavernosus clitoridis 

major). 

(bb) Lesser cavernous nerves of clitoris (Nn. cavernosi clitoridis 

minor es). 

Pelvic Fascia (Fascia pelvis) in the Female. (Vide Spalteholz, Fig. 

667.) 

To expose the pelvic fascia from above, remove the perito- 
neum by blunt dissection from the viscera and the pelvic wall. 
This should be done on one side only. Avoid injury to the ves- 
sels and nerves. The anterior leaf of the broad ligament may 
also be left. Study now the following divisions of the fascia : 

(a) Superior fascia of pelvic diaphragm (fascia diaphragmatis pelvis 

superior). 

(b) Tendinous arch of pelvic fascia (arcus tendineus fasciae pelvis). 

(c) Tendinous arch of levator ani muscle (arcus tendineus M. levatoris 

ani). 

(d) Endopelvic fascia (fascia endopelvina) . 



542 LABORATORY MANUAL OF HUMAN ANATOMY 

Determine the relation of this fascia to the uterine and vaginal 
walls. 

(e) Middle pubovesical ligament (Lig. pubovesicale medium). 

(f) Lateral pubovesical ligaments (Ligg. pubovesicalia lateralia). 

(g) Inferior fascia of pelvic diaphragm (fascia diaphragmatis pelvis 

inferior). 

The latter fascia has already been studied in the dissection of the 
fossa ischiorectalis. It should now be reviewed and its relation to 
the fascia obturatoria and the arcus tendineus M. levatoris ani 
established. 



Pelvic Vessels and Nerves. 

Dissect out the arteries and veins of the pelvis. Consult the 
pages on the male pelvis, noting the differences. Study the 
following : 

Arteries. 

(a) Uterine artery (arteria uterina). (Vide Spalteholz, Fig. 471.) 

(aa) Vaginal artery (A. vaginalis). 

(ab) Tubal branch (A. tubarius). 

(ac) Branch to ovary (ramus ovarii). 

Pay especial attention to the relation between the uterine 
artery and the ureter. At what distance from the cervix uteri 
does the artery cross the ureter? 

(b) Ovarian artery (A. ovarica). 

Through what ligament does the ovarian artery pass to reach 
the ovary? What is its relation to the ligamentum suspensorium 
ovarii ? 

Veins. 

(a) Uterovaginal plexus (plexus uterovaginalis) . (Vide Spalteholz, 
Fig. 502.) 

Lymphatics. 

Use special preparations for this study. (Consult Poirier et Charpy, 
i. 5, Figs. 338, 339.) Determine into what lymph-nodes the lymphatics 
of the cervix and the body of the uterus empty. 

Pelvic Spinal Nerves. 

Consult the directions in regard to the male pelvis for the dissection 
of these nerves. 

Rectum (Intestinum rectum). (Vide Spalteholz, Figs. 575, 576, 591, 
655 656, 665.) 

The female rectum does not differ materially in structure 
from that of the male. Its relations should be carefully studied. 
Establish its relations to the posterior vaginal wall and the 
perineal body. Use models and cross-sections as supplementary 
to the cadaver for this purpose. 



ABDOMEN AND PELVIS 



543 



Bladder (Vesica urinaria). (Vide Fig. 292, and Spalteholz, Figs. 633, 

640.) 

Compare the form of the bladder in the two sexes; also its 
position in the pelvis. Distend the bladder with air. How does 
the naturally distended bladder compare in form with the 
empty! Consult the pages on the male pelvis for the nomen- 
clature of the bladder and the directions for dissection. 

Pelvic Part of Ureter (Pars pelvina ureteris). (Vide Fig. 291, and 
Spalteholz, Fig. 665.) 

Isolate the ureter as it passes into the pelvis at the bifurca- 
tion of the common iliac arteries. Compare the lengths of the 
pelvic divisions in the male and female. Trace the ureter for- 
ward to the base of the broad ligament. Establish its relations 
to the uterine artery. What surgical significance has this ana- 
tomical relation? 



FIG. 291. 



Plexus uterovaginalis 

V. uterina 
L 




. 
Plex. ves. stve vesicovaginahs 

V. uterina ant. 
A. cervicovaginalis 
A. vaginalis 



Diagram showing the relations of the ureter to the cervix [uteri] and adjacent vessels. The line 
LL passes a little below the vaginal isthmus of the uterus. The longitudinal striations indicate the 
vaginal wall, and the dotted line shows the contour of the cervix uteri. The vertical line, 25 mm., 
indicates the length of the cervix uteri. (From Poirier et Charpy, Trait6 d'Anat. hum., Paris, 1901, t. v. 
p. 457, Fig. 320.) 

Trace the ureter forward to the bladder and establish its 
relation to the anterior vaginal wall. At what angle does the 
ureter enter the bladder! 



Uterus (Uterus) (O. T. Womb). (Vide Spalteholz, Figs. 662, 664, 
665, 667.) 

Use models and special preparations for this study. Estab- 
lish the position and relations of the uterus. How does the 
infantile compare with the adult organ? 

(a) Body of uterus (corpus uteri). 

(aa) Fundus of uterus (fundus uteri). 

(ab) Lateral margin (margo lateralis). 



544 



LABORATORY MANUAL OF HUMAN ANATOMY 



(ac) Vesical surface (fades vesicalis). 

(ad) Intestinal surface (fades intestinalis) . 

(ae) Cavity of uterus (cavum uteri). 
(b) Neck of uterus (cervix uteri). 

(ba) Supravaginal part of neck (portio supravaginalis [cervids]). 

(bb) Vaginal part of neck (portio vaginalis [cervids]). 



FIG. 292. 




Median section of the body of a woman. 

V, uterus; B, urinary bladder; Prom, promontory of the pelvis; Sym, symphysis ossium pubis; 
Cerv, cervix of the uterus. The dotted line shows the position of the upper boundary of the hip-bone. 
(After Cullen, Cancer of the Uterus, Baltimore, 1900, p. 7, Fig. 3.) 

(be) External orifice of uterus (orifidum uteri externum) (0. T. 
external os). 

(bca) Anterior lip (labium anterius). 

(bcb) Posterior lip (labium posterius). 

(bd) Canal of neck of uterus (canalis cervids uteri). 

(be) Internal orifice of uterus (orifidum internum uteri) (0. T. 

internal os). 



ABDOMEN AND PELVIS 



545 



Vagina. (Vide Figs. 290, 292, and Spalteholz, Figs. 664, 665.) 

Note the ]ength of its anterior and posterior walls. Palpate 
the cervix uteri. How does it differ in the parous and nulli- 
parous? What is the relation of its long axis to the pelvic brim? 



FIG. 293. 



Ampulla tubae uterinae 
Iniundibulum tubae \ 

uterinae \ 
Ostium abdominale \ 
tubae uterinae \ ' , 

\ V 

Fimbriae tubae " * 



Fimbria ovarica 
Mesosalpinx 
/ Epoophoron 



Ligamentum suspensorium ovarii 
Inf undibulum tubae uterinae" - 



Ovarium dextrum 
, Isthmus tubae uterinae (facies medialis) 

' Lig. ovarii Tuba uterina 

proprium (Falloppii) 

/ Lig. ovarii \ 

proprium., ' 




Appendix 
vesicu- 
IOSM [Morgagnii]' 

A. and v. ovarica' 
LigMiiii-iituin suspen-' / 
sorium ovarii / 

f Extremitas/' ^| 
tubaria / /'' 
Mesovarium / , v 
Ovarium \ Facies medialis / 
simstrum Margo liber / 

Liga men turn f 
latum uteri 

Extremitas uterina ovarii 



Ureter 



Ureter 
M. recto-uterinus 



Uterus ( facies intestinalis) 



! Excavatlo recto-uterina [cavum Douglasi] 

Plica recto-uterina [Douglasi] 

Uterus, Fallopian tubes, and ovaries, viewed from behind. (On the right the parts have been left 
in their natural position, on the left the ligamentum latum has been unfolded.) (After Spalteholz, 
Hand Atlas of Hum. Anat., Leipzig, 1903, vol. iii. p. 59G, Fig 662.) 

Determine its relations to the bladder and rectum. Pass a probe 
through the ureter from the pelvis and determine the relations 
of the ureter to the vaginal wall. What is the relation of the 
urethra f Study 

(a) Fornix of vagina (fornix vaginae). 

(b) Anterior wall (paries anterior). 

(c) Posterior wall (paries posterior). 

(d) Hymen (hymen [femininus]). 

(e) Hymeneal caruncles (carunculae hymenales). 

A re the latter present ? If so, what is their significance ? 
(/) Muscular coat (tunica muscularis). 
(g) Mucous coat (tunica mucosa). 

(ga) Vaginal lymph-nodules (noduli liiin }ilniliri r<t</inales). 

(gb) Rugae (rugae vaginales). 

(gc) Columns <;!' the rugae (columnae rugarum). 

(f/rd) Posterior (columna rugarum posterior). 
(//</>) Anterior (mlnmna rugarum anterior}, 
(gcc) Carina urethralis [vaginae]. 



35 



546 LABORATORY MANUAL OF HUMAN ANATOMY 

Ovary (Ovarium). 1 (Vide Figs. 293, 295, and Spalteholz, Fig. 632.) 

(a) Hilus of ovary (hilus ovarii). 

(b) Medial surface (fades medialis). 

(c) Lateral surface (fades later alis}. 

(d) Free margin (mar go liber). 

(e) Mesovarian margin (margo mesovarica). 

(f) Tubal extremity (extremitas tubaria). 

(g) Uterine extremity (extremitas uterina). 

(h) Proper ligament of ovary (ligamentum ovarii proprium). 
(i) Corpus luteum (corpus luteum) ("yellow body"). 
(j) Corpus albicans (corpus albicans) ("white body"). 

Examine section of ovary under hand-lens. 
(k) Stroma of ovary (stroma ovarii). 

(I) Primary ovarian follicles (folliculi oophori primarii). 
(m) Vesicular ovarian follicle (folliculus oophori vesiculosus [Graafi]). 
(n) Theca of follicle (theca folliculi). 

(na) External tunic (tunica externa). 

(nb) Internal tunic (tunica interna). 
(o) Liquor of follicle (liquor folliculi). 
(p) Granular layer (stratum granulosum). 
(q) Cumulus oophorus (0. T. discus proligerus). 

(qa) Ovule (ovulum). 

What is the relation of the ovary to the posterior layer of 
the broad ligament ! What is the ' ' germinal epithelium ' ' ? Has 
the ovary a serous covering comparable to that of the testicle? 

Examine the broad ligament with the naked eye and under a 
hand-lens and study the following structures. Determine what 
embryonic structures they are developed from, and what their 
homologues in the male are. 

(a) Paroophoron (paroophoron) . 

(b) Epoophoron (epoophoron). 

(ba) Longitudinal duct of epoophoron (ductus epoophori longi- 

tudinalis [ Gdrtneri] ) . 
(bab) Transverse ductules (ductuli transversi). 

(bb) Vesicular appendages (appendices vesiculosi [Morgagnii]) . 



Uterine Tube (Tuba uterina [Fallopii]) (O. T. Fallopian Tube). 

(Vide Spalteholz, Figs. 662-664, 667.) 

Determine the positions and axes of the tubes, also their rela- 
tions to the neighboring viscera. From what does the Fallopian 
tube develop ? Note the following : 

1 For a detailed account of the blood-supply of the ovary, see " Origin, De- 
velopment, and Degeneration of the Blood-vessels of the Human Ovary," by 
J. G. Clark, in Contributions to the Sci. of Med., Baltimore, 1900. 



ABDOMEN AND PELVIS 547 

(a) Abdominal mouth of uterine tube (ostium abdominale tubae uter- 

inae ) . 

This communicates with the peritoneal cavity. 

(b) Infundibulum of uterine tube (infundibulum tubae uterinae). 

(c) Fimbriae of tube (fimbriae tubae). 

(ca) Ovarian fimbria (fimbria ovarica). 

(d) Ampulla of uterine tube (ampulla tubae uterinae). 

(e) Isthmus of uterine tube (isthmus tubae uterinae). 

FIG. 294. 




Miillerian duct 

Lig. ovarii proprium 



Lig. teres uteri 



Scheme of the development of the internal female genital organs, showing their initial situation 
ami tlicir situation again after apparent descent. Organs which persist are in unbroken outline (except 
the ovary in the lower position), those that atrophy are in dotted outline (Hertwig). (After Poirier et 
Clmrpy, Traite d'Anat. hum., Paris, 1901, 2 ed., t. v. p. 399, Fig 290.) 

Round Ligament of Uterus (Ligamentum teres uteri). (Vide Spalte- 
holz, Figs. 665, 667, 675.) 

Dissect out the round ligament forward to the annulus in- 
guinalis abdominalis. Do any lymphatics accompany the round 
ligament? If so, with what lymph-nodes do they communicate? 
From what is the round ligament developed, and what is its 
homologue in the male? What is its function? What is the 
vaginal process of the peritoneum (processus vaginalis peri- 
tonaei) (O. T. canal of Nuck ) .' 

Diaphragm of the Pelvis (Diaphragma pelvis). (Vide Spalteholz, 

Figs. 670, 671.) 

Dissect out the following muscles and determine their rela- 
tions to the bladder, vagina, uterus, and rectum. Compare these 
muscles with those in the ma ] e, noting carefully any differences. 



548 LABORATORY MANUAL OF HUMAN ANATOMY 

(a) Levator muscle of anus (M. levator ani). 

(aa) Pubococcygeus muscle (M. pub o coccygeus). 

(ab) Iliococcygeus muscle (M. iliococcygeus). 

(b) Coccygeus muscle (M. coccygeus}. 

Remove the viscera from the pelvic cavity. Divide the ves- 
sels and nerves connected with the viscera, the levator ani mus- 
cle, and the pubovesical ligaments. Divide the structures hold- 
ing the urethra and vagina to the pubic arch. Separate the 
rectum from the sacrum and coccyx. Now study- 
Other Pelvic Muscles and Fascia. 

(a) Obturator internus muscle (M. obturator internus). (Vide Spalte- 

holz, Fig. 373.) 

(b) Obturator fascia (fascia obturatoria). 

(c) Piriform muscle (M. piriformis). 

Rectum (Intestinum rectum). (Vide Spalteholz, Fig. 576.) 

Dissect the rectum away from the vagina and uterus. Open 
the rectum along its anterior wall and study its 

(a) Mucous membrane (tunica mucosa). 

(aa) Transverse rectal folds (plicae transversales recti). 

(ab) Lymph-nodules (noduli lymphatici). 

In the anal part of the rectum (pars analis recti) study 

(ac) Rectal columns of Morgagni (columnae rectales [Morgagnii]). 

(ad) Hemorrhoidal ring (annulus haemorrhoidalis) . 

(b) Submucous tela (tela submucosa). 

(c) Muscular tunic (tunica muscularis). 

(ca\ Longitudinal layer (stratum longitudinale) . 

(caa) Rectococcygeus muscle (M. rectococcygeus). 
(cb) Circular layer (stratum circular e). 

Note that the circular fibres are increased in 
number in the base of each transverse rectal fold. 
(cba) Internal sphincter muscle (M. sphincter ani in- 
ternus). 

Female Urethra. 

Open the bladder along its anterior surface. Carry the in- 
cision along the anterior wall of the urethra. Pin the urethra 
and bladder down upon a cork dissecting-tray and study the 
female urethra (urethra muliebris). (Vide Spalteholz, Fig. 
642.) Compare it with the male urethra, noting differences. 

(a) External urethral orifice (orificium urethras externum). 

(b) Spongy body of urethra (corpus spongiosum urethrae). 

(c) Muscular tunic (tunica muscularis). 



ABDOMEN AND PELVIS 549 

(ca) Circular layer (stratum circular e}. 

(cb) Longitudinal layer (stratum longitudinale) . 

(d) Submucous tunic (tunica submucosa). 

(e) Mucous tunic (tunica mucosa). 

(ea) Urethral glands (Gl. urethrales). 

(eb) Urethral crest (crista urethralis). 

Urinary Bladder (Vesica urinaria). (Vide Spalteholz, Fig. 642.) 

Refer to the pages on the male pelvis. Compare the blad- 
der of the female with that of the male as to form, size, and mus- 
culature. 

Interior of Vagina. 

Open the vagina along its anterior wall. Carry the incision 
into the uterus and lay open the Fallopian tube on each side. 
Study at this time also the relations of the ovary and its liga- 
ment to the uterus. 

Pin down the structures upon a dissecting-block and study 
the following. (Vide Spalteholz, Fig. 664.) 

(a) Muscular tunic (tunica muscularis). 

(b) Mucous tunic (tunica mucosa). 

(ba) Vaginal lymphatic nodules (noduli lymphatici vaginales). 

(66) Vaginal rugae (rugae vaginales). 

(be) Columns of rugae (columnae rugarum). 

(bca) Posterior column of rugae (columna rugarum pos- 

terior). 

(bcb) Anterior column of rugae (columna rugarum an- 

terior). 

(bcc) Urethral carina (carina urethralis [Morgagnii] ). 

Interior of Uterus. (Vide Fig. 295, and Spalteholz, Fig. 664.) 

(a) Cavity of uterus (cavum uteri). 

(b) Internal orifice of uterus (orificium uteri internum) (0. T. internal 

os). 

(c) Neck of uterus (cervix uteri). 

(ca) Supravaginal part of cervix (portio supravaginalis [cer- 

vicis]). 

(cb) Vaginal part of cervix (portio vaginalis [cervicis]). 

(cba) External orifice of uterus (orificium uteri externum) 
(0. T. external os). 

(1) Anterior lip (labium anterius). 

(2) Posterior lip (labium postcrius). 

(d) Canal of neck of uterus (canalis cervicis uteri). 

(da) Palmate folds (plicae palmatae). 

(db) Cervical glands (Gl. cervicales). 

(e) Parametrium (parametrium). 

(f) Serous tunic (tunica serosa [perimetrium]) . 



550 



LABORATORY MANUAL OF HUMAN ANATOMY 



(g) Muscular tunic (tunica muscularis}. 

(h) Muscular tunic of neck (tunica muscularis [cervicis] ). 

(i) Mucous tunic (tunica mucosa). 

(ia) Uterine glands (Gl. uterinae). 

Interior of Uterine Tube (Tuba uterina [Fallopii]) (O. T. Fallopian 
Tube). (Vide Fig. 295, and Spalteholz, Fig. 664.) 

(a) Uterine part (pars uterina). 

(b) Uterine opening of tube (ostium uterinum tubae). 

(c) Serous tunic (tunica serosa). 

(d) Adventitious tunic (tunica adventitia). 



Ostium 
uterinum tubae 



FIG. 295. 

Epoophoron (ductulus longitudinalis) 

Tunica serosa 
Mesosalpinx 
Isthmus tubae 
Pars uterina tubae ! 



Ampulla tubae 

Plicae (ampullares) tubariae 
/\ Epoophoron (ductuli transversi) 
'- - Ostium abdominale tubae 



Canalis cervicis 
Plicae palmatae 

Orificium extern- 
urn uteri 




Cavum uteri 

Tunica 

muscularis uteri' 
Tunica mucosa 
Orificium intern- 
um uteri 



! 

Appendix vesiculosa 
/ (Morgagnii) 

Plexus (venosus) uterovaginalis 



\ ] Plexus (venosus) ovaricus 

\ Hilus ovarii 

' Mesometrium 
' A. uterina 
Margo lateralis uteri 
' Fornix vaginae 

The uterus and right Fallopian tube, tuba uterina, opened up posteriorly. The peritoneum has 
been stripped off the posterior surface of the broad ligament. (After Toldt, Anat. Atlas, Wien, 1900, 
2Aufl., p. 496, Fig. 847.) 

(e) Muscular tunic (tunica muscularis). 

(ea) Longitudinal layer (stratum longitudinale) . 

(eb) Circular layer (stratum circular e). 

(f) Submucous tela (tela submucosa). 

(g) Mucous tunic (tunica mucosa) . 

(ga) Tubal folds (plicae tubariae). 

(gaa) Ampullar folds (plicae ampullares). 

(gab) Isthmian folds (plicae isthmicae). 



ABDOMEN AND PELVIS 



551 



JOINTS OF THE PELVIS. 

In studying the following joints determine the general char- 
acteristics of the bony surfaces entering into their formation. 
Study the movements which occur between the joint surfaces, 
the muscles which produce these movements, and the mechanism 
by which they are restricted. Pay particular attention to the 

FIG. 296. 



__.,Lig. sacrococcygeum 
anterius 




Articulations and ligaments of the pelvis. Anterior view. The os pubis and the os ischii have been 
partly cut away. (From Poirier et Charpy, Trait<5 d'Anat. hum., Paris, t. i. p. 700, Fig. 706.) 

synovial membranes and their relations to the joint-cavity. Re- 
view the bursae which you have found in your previous dissec- 
tion, and establish their relations to the joints. If the ligaments 
have dried, their dissection may be rendered easier by soaking 



552 



LABORATORY MANUAL OF HUMAN ANATOMY 



them in water. Eemove the pelvic muscles and nerves. The 
origins and insertions of the muscles should be carefully meas- 
ured and charted before they are removed. 



FIG. 297. 



---- Lig. supraspinale 



Lig. iliolumbale 




-Lig. sacro- 
iliacum 
post. long. 



.Lig. saero- 

iliacum 
post, breve 



- Lig. sacrospinosum 



Lig. sacrotuberosum 



Lig. sacrococcygeum ', 

posterius 
Lig. sacrococcygeum laterale 

Articulations and ligaments of the pelvis. Posterior view. (From Poirier et Charpy, Traite" 
d'Anat. hum., Paris, t. i. p. 701, Fig. 707.) 



Ligaments of the Pelvic Girdle (Ligg. cinguli extremitatis inferioris). 
(Figs. 296 and 297.) 

(a) Obturator membrane (membrana obturatoria) . 

(aa) Obturator canal (canalis obturatorius) . 

(b) Iliolumbar ligament (ligamentum iliolumbale) . 

(c) Sacrotuberous ligament (ligamentum sacrotuberosum) (0. T. poste- 

rior or great sacrosciatic ligament). 

(ca) Falciform process (processus falciformis) (O. T. falciform 
ligament). 



ABDOMEN AND PELVIS 553 

(d) Sacrospinous ligament (ligamentum sacrospinosum) (0. T. anterior 
or small sacrosciatic ligament). 

(da) Greater sciatic foramen (foramen ischiadicum ma jus}. 

(db) Lesser sciatic foramen (foramen ischiadicum minus). 

Sacro-iliac Joint (Articulatio sacro-iliaca). 

(a) Anterior sacro-iliac ligaments (Ligg. sacroiliaca anteriora). 

(b) Interosseous sacro-iliac ligaments (Ligg. sacroiliaca inter ossea}. 

(c) Short posterior sacro-iliac ligament (Lig. sacroiliacum posterius 

breve). 

(d) Long posterior sacro-iliac ligament (Lig. sacroiliacum posterius 

longum). 

Divide the ligaments and separate the bones. Study the 
synovial space. 

FIG. 298. 




Frontal section through the symphysis ossium pubis. (From Gegenbaur, Lehrb. der Anat. des 
Mcnsch., Leipzig, 1899, 7 Aufl., Bd. i. p. 293, Fig. 231.) 

Symphysis of Pubic Bones (Symphysis ossium pubis). (Fig. 298.) 

(a) Superior pubic ligament (Lig. pubicum superius). 

(b) Arcuate ligament of pubis (Lig. arcuatum pubis). 

(c) Interpubic fibrocartilaginous lamina (lamina fibrocartilaginea inter- 

pubica). 

Use the chisel and remove a piece of the bone from the front 
of the joint. Study the interpubic fibrocartilaginous lamina and 
the synovial membrane of the joint-cavity. 

Symphysis of Sacrum and Coccyx (Symphysis sacrococcygea). 

(a) Superficial posterior sacrococcygeal ligament (Lig. sacrococcygeum 

posterius superficiale) . 

(b) Deep posterior sacrococcygeal ligament (Lig. sacrococcygeum pos- 

terius profundum). 

(c) Anterior sacrococcygeal ligament (Lig. sacrococci/f/rinn (uitcr/its). 

(d) Lateral sacrococcygeal ligament (Lig. sacrococcygeum lat< r/r). 



CORRIGENDA 



Page 31. Among " General Works" the books of Henle and Hyrtl should 
have been included. 

Page 77. At side of figure, instead of " M. brachiodorsalis" read " M. 
brachioradialis." 

Page 99. At side of figure, instead of " M. adductor pollicis brevis" read 
" M. abductor pollicis brevis." 

Page 127. At side of figure, instead of " A. pudenda communis" read " A. 
pudenda interna." 

Page 132. At side of figure, instead of " N. saphena mag." read " V. 
saphena magna." 

Page 161. At side of figure, instead of " N. et M. peronaea long." read 
" Nerve to the M. peronaeus longus." 

In same figure, instead of " M. peronaeus prof." read " N. peronaeus 
profundus." 

Page 164. At side of figure, instead of " N. tiabialis" read " N. tibialis." 

Page 186. On figure, instead of " Lig. tibiocalcaneum" read " Ligamentum 
calcaneotibiale." 

Page 198. On fig-ure, instead of " Gyrus cerebri" read " Cortex cerebri." 

Page 224. At side of figure, instead of " M. trapezoideus" read " M. 
trapezius." 

Page 252, line 11. Instead of "External carotid" read "Branches of 
external carotid." 

Page 412. At side of figure, instead of " Ost. atrioventr. dextrum" read 
" Ostium venosum dextrum." 

Page 437. At side of figure, instead of " A. pudendus externus" read " A. 
pudenda externa;" also, instead of "A. perinei superficialis" read "A. perinei." 

Page 440. At side of figure, instead of " N. ischiocavernosus" read " M. 
ischiocavernosus;" also, instead of " N. pudendus" read " N. perinei;" instead 
of " N. cut. N. fern, post." read " N. cutaneus femoris posterior." 

Page 441. At side of figure, instead of " N. trans, perinei prof." read 
" M. transversus perinei profundus." 

Page 497. At side of Fig. B, instead of " fusion to" read " fusion with." 

Page 506. In foot-note, instead of " perineal" read " perirenal" in two 
places. 

Page 522. At side of Fig. 276, instead of " Fibro-elastic network of the 
int. rect." read " Fibro-elastic network of the rectum ;" also, instead of " N. sph. 
ani ext. subcut." read " M. sphincter ani subcutaneus." 

Page 523. In figure, instead of " Fossa ischiorectale" read " Fossa ischio- 
rectalis." 

Page 531. In figure, instead of " A. bulbo-urethrae" read " A. bulbi 
urethrae." 

Page 503 et seq. Instead i.f " Index l< N \\ Terms" read "Index to Terms 
now used." 



INDEX TO ILLUSTRATIONS 



Absolute heart dulness, 456 
Annulus inguinalis abdominalis, 453 
subcutaneus, 453 

tendineus communis. 280 

urethralis, 538 

Aorta abdominalis and branches, 512 
Appendix vesiculosa [Morgagnii], 550 
Arc-iis tendineus M. levatoris ani, 534 
Arteria axillaris, 63 

carotis, 274 

cerebri media, 320, 321 

coeliacus, 491 

femoralis, 137, 147 

glutaea, 127 

- intercostalis, 401 

lingualis, 267 

maxillaris externa, 267 

meningea media. 21)0 

mesenterica inferior, 479, 495, 496 

superior, 475 

obturatoria, 520, 530, 531 

ophthalmica, 278 

phrenica, 491, 512 

poplitea, 134 

- pvofunda penis. 538 

pudenda iuterna. 530 

subclavius, 63, 221 

- thyreoidea superior, 267 

uterina, 543, 550 

- vertebralis, 285 

Arteries of anterior body-wall, 56 

of base of brain, 319 

of body wall, in section, 401 

of head, 236, 319 

of knee. 181 

of leg, 159, 171, 185 

of neck, 210, 236 

of palm, 97 

of pelvic wall and floor, 531 

of perineum, 13v) 

of popliteal space, 133, 134 

of rectum, 532 

of retina, 382 

of shoulder. 219 

- transformation of branchial, 421 
Art iculations : 

acromioclavicular, 72, 85 

ankle, 186. 187 

atlanto-epistrophic, 286. 287 

- atlanto-occipital, 286, 287, 294 

carpal, 113 

elbow, 110, 111 

foot. 189, 190 

hip. 154. 155 

knee. 132. 1S1. 182. 183, 184 

pelvic. 551. 552. 553 

- radlo-ulnar. 112. 113, 114 

- shoulder. 85. 86 
Axillary arch, 59 

- fascia. 59, 60 

fossa, 60 

Base of skull, 200 
Blood-vessels of eyeball, 378 
Brachial arch, 59 

- plexus. 63. 75. 215 

Brain, base. 318. 310, 333, 344 

- Intern I surface. .".L'O. 332 

median surface. .'!.'!! 
Bronchi. 425 

Bulbus urethrae, 5 .",8 

Capsule of Tenon, 256 
Cartilages of larynx, 425 



Cerebellum, 327, 328, 329 

Cerebrum, 332, 333 

Cervicobrachial plexus, 66, 215, 221, 285 

Cervix uteri, 543 

Chorda tympani. 274, 306 

Ciliary body, 379 

processes, 379 
Cisterna chyli, 478 
Columnae rectales, 536 
Conjunctiva bulbi, 256, 375, 377 

palpebrarum, 256 
Crista urethralis, 538 

Development of female genitalia, 547 
Ductus choledochus, 491, 494, 496 

deferens, 512, 527 

ejaculatorius, 527, 538 

- lymphaticus dexter, 469 

thoracicus, 478 
Duodenal fossae, 469 

Epididymis, 462 

Epoophoron, 550 

Excavatio recto-uterina, 540 

Exit of cerebral nerves, 200 

Exposing pelvic fascia, 520, 521 

Fascia. 76, 77 

- bulbi, 256 

- colli, 206, 210, 211, 227 

coracobrachialis, 219 

cribrosa, 515 

of fusion, 497 

infraspinata, 232 

- lata, 515 

lumbodorsalis, 232 

parotideus, 249 

of pelvis, 522, 523 

of perineum, 437, 441, 442, 443 

- perirenal, 507 

prerenal. 507 

prevertebral. 289 

retrorenal, 507 

supraspinata. 232 

- of Toldt, 507 

- of Treitz, 497 
Flexura coli dextra, 495 

duodeni inferior, 493 

duodenojejunalis, 493 

superior, 493 
Fundus oculi, 382 

Ganglion, cervical sympathetic. 285 

- ciliary. 281 

- geniculate, 306 

otic, 299, 306 

- semilunar. 299, 306 

sphenopalatine. 281, 304 

sympathetic, 515 
Gland, lacrimal, 281 

- parotid, 206. 219, 267 

- submaxillary. 206, 267 

suprarenal. 405 
Glans penis. 53s 
Granulationes arachnoideae, 199 
Great omentum, 491 

Heart, dulness. 406 

opening chambers of, 414, 416, 419 

Inguinal canal. 453. 450 

- ligament. 146. 512. 515 

- region, 146. 151 
Intestine, caecum, 488 

555 



556 



INDEX TO ILLUSTRATIONS 



Intestine, course of, 482 

duodenum, 493, 496 

jejunum, 484, 493 

large, 487 
Iris. 380 

Isthmus rhombencephali, 345 

Joints. See Articulations. 
Kidney, 495, 497, 504, 512 

Labyrinth, bony, 295, 392 

membranous, 393, 395 
Lacrimal ducts, 257 
Lacunae urethrales, 538 
Larynx, 292, 308. 309 
Leg-supports, 436 

Lens, 383 

Ligaments. See also Articulations. 

Ligament(s), Ligamentum(i) : 

coronarium hepatis, 504 

gastrolienale, 501 

- inguinal. 146, 512, 515 

of ankle, 162. 173 

of pelvis, 551, 552 

of scapula, 72 

puboprostatic, 524 

- round, of uterus, 459 

suspensorium penis, 515 

teres hepatis, 503 

umbilicale medium, 524 

venosum (hepatis) [Arantii], 503 
Lithotomy position, 436 

Liver, 503, 504 
Lungs. 403, 406, 407 
Lymphatics of arm. 62 

of axilla, 62, 205. 223, 478 

of breast, 62, 205, 223 

of forearm. 91 

of hand. 62. 91 

of head, 205. 223 

of iliac region. 478 

of inguinal region, 139, 478 

of leg, 131 

of lower limb, 131 

of neck, 205, 223 

of penis. 139 

of posterior wall of trunk, 478 

of thigh, 131 

of thorax, 62, 205 

Mamma, 57 

Medulla oblongata, 323, 330, 345 

Mesentery. 481 

Midbrain, 323, 330 

Middle ear. 299. 306 

Miller's model of lung 427 

Mouth, 289 

Muscle, Muscles : 

coccygeus. 534 
- iliacus, 515 

levator ani, 534 

obliquus abdom. ext.. 515 

of abdomen, 146, 453 

of back, 49 232 

of cheek. 292 

of ear, 249, 253 

of eye. 277. 280. 281 

of far<>. 2-p.i. L' .">.; 

of fingers, 102. 1OR 

of floor of mouth. 221 

of foot. 1(52. 172. 177 

of forearm. 95 

of hand, 99 

of larynx. 265. 312 

- of leg. 1(51. IT.'!. 174 

of neck. 210, 21 24 227 93 OQ 

- of orbit, 277, 280, 281 ' 

of pectoral region. r>s 

of pelvic floor. 534 

- of perineum, 437. 438. 440, 441, 443, 446 

of pharynx. 2r,r.. 292 

of platysnia. 208, 249 

of shoulder. 83 

of submaxillary region, 267 



Muscle, Muscles : 

- of thigh, 147, 151 

- of tongue. 265, 316 

of wall of trunk. 50, 401 

psoas major, 515 

- pubovesicalis. 529 

quadratus lumborum, 515 

Nasolacrimal duct, 257 

Nerves of anterior surface of trunk, 54 

- of arm, 69, 75 

- of face, 253 

- of foot, 143, 161, 167 

of forearm, 81. 88. 95 

of gluteal region, 124, 128 

- of hand, 88. 89 

- of leg. 143, 161, 167 

of lumbar plexus, 515 

- of neck, 208, 253 

of nose, 304 

- of orbit. 278. 280, 281 

of perineum, 440, 446 

- of scalp, 253 

- of shoulder. 69, 75. 83 

- of thigh. 124, 143, 151 
Xervus, Nervi : 

abducens. 273 

auricularis magnus, 253 

auriculotemporalis, 253 

cardiaci, 221 

cerebrales, 200, 318 

chorda tympani. 274, 306 

dorsalis penis, 515 

- facialis, 253, 306 

glossopharyngeus, 265 
- hypoglossus, 265 

- lingualis, 265 

mandibularis and rami, 263 

maxillaris. 273 

nasopalatinus. 300 

occipitalis, 253 

oculomotorius, 273. 281 

- olfactorii, 300, 304 

ophthalmicus. 273 

palatinus (ant., post, med.), 304 

- recurrens, 265 

- spinalis, 47, 240, 241, 245, 400 

- trigeminus and rami, 274, 281, 299, 306 

- trochlearis, 273 

- vagus. 221 

Xoduli lymphatici aggregati, 485 

solitarii, 485 
Nose, 289 
Nuclei of cerebral nerves, 374 

Opening mediastinum, 404 
Orbital septum, 256 
Organ of Corti. 396 
Ovary, 540, 545, 550 

Pacchionian bodies, 199 

Palmar sheaths, 101 

Pancreas, 491, 495. 497 

Papilla duodeni. 493 

Pelvis renalis, 510 

Penis, 538 

Peritoneum. 455. 495, 497, 544 

Pharynx. 289, 292 

Pleura, 406 

Plexus lumbalis. 517 

lumbosacralis, 517 

pudendus. 517 

sacral is. 517 

Plica longitudinalis duodeni, 493 
Plicae circulares. 4!>: > , 
Pons. 323. 327. 330, 345 
Popliteal fossa, 133 
Poupart's ligament, 146 
Pronation. 112 
Pylorus, 493 

Reconstruction of lobule of lung, 427 
Kegions of anterior surfaces. 43 

of posterior surfaces, 43 

- perineal, 434, 435 



INDEX TO ILLUSTRATIONS 



557 



Regions urogenital, 434, 4:;r> 
Renal calices, .">!( 
Kosenmiiller's lymph-gland. 478 

Schema of blood-supply of alimentary tract, 
463, 464 

- of circulation, 410 

of embryonic alimentary tract, 463, 464, 
465 

of male genital organs. 460 

of peritoneum, 466, 4(>7 

of veins, 411 
Sections of arm. 76, 77 

of atlanto-epistrophic articulation, 286 

of atlanto-occipital articulation, 286 

of axillary fossa. 60 

- of brain, 321. 336, 340, .",42 

- of brain-stem, 327, 360, 361 

of breast. 57 

- of cerebellum. 327, 350, 351, 352 

of cerebral hemisphere. 370 

of corpora mammillaria, 363 

of corpora quadrigemina, 355, 356, 357 

of corpus callosum, 327, 362, 363 

- of ear, 385, 386, 387, 388, 389. 390 
of elbow, 109. 110 

of eyeball. 375. :\77. 378 

- of falx cerebri. 199 

of female genitalia. 540, 544 

- of foot. 190 

- of forearm, 89. 92, 93, 106 

- of hand, 100. 113 

- of hip-joint, 155 

of hippocampus, 342 

of hypophysis. 302 

of isthmus rhombencephali, 353 

- of knee, 132 

- of larynx, 309 

- of leg. 158, 164 

of liver, 504 

of median plane of female body, 544 

of median plane of head, neck, thorax. 289 

of medulla oblongata, 347, 348, 349, 
350, 351. 362 

- of meninges, 198, 199, 239 

of mesencephalon. 356, 357 

of nasopharynx, 294 

- of neck, 211, 227, 289 

- of nose, 289, 300. 301, 302 

- of orbit, 256, 277 

- of palate, 294. 300, 301, 302. 304 

of pelvic and perineal fasciae, 441, 442. 
443 

- of pelvis, 455, 522, 523 

- of pharynx. 227, 294 

- of pons. 352, 353. 355 

of shoulder. 61, 85 

of sinus cavemosus. 273 

of sinus ephenoldalis, 'JT.'i 

- of spinal cord. 240. 244, 245, 246 

of stomach wall, 499 



Sections of symphysis pubis, 553 

- of testis, 461 

- of thigh, 144, 149 

- of third ventricle, 341 

- of thorax, 400, 401, 403 

of tongue, 316 

of trunk in median plane, 466 

of trunk, transverse. 467, 497 

of uterine tube. .">< 

of uterus, 550 

of vagina, 446 

of vesicula seminalis, 527 

of vulva, 446 
Sinus cavernosus, 273 

sphenoidalis. 273 

Skin incisions of anterior surfaces, 53 

of head and neck, 195 

of perineum, 436 

of posterior surfaces, 46 
Spermatic cord, 457 

Spinal cord, 323, 330 
Spleen, 491, 495, 497, 501 
Stomach, 491, 497 
Supination, 112 
Surface of palm, 97 
Sympathetic in neck, 221, 285 

- in trunk, 241 

Synovial spaces of knee, 184 

Tarsal cartilages, 256 
Tear-sac, 257 

Tendons of fingers, 102, 108 
Testis, 457, 461, 462 
Thoracic duct, 426 
Tongue, 315, 316 
Trachea, 289, 425 
Truncus intestinalis, 478 
Tuba uterina. 545 

Tympanum, 385, 386, 387, 388, 389, 390, 
391 

Ureter, 510. 512, 543 
Urethra, 538, 544 
Urogenital system, 461 
Uterus, 540, 544, 545 
Utriculus prostaticus, 538 

Vagina, 540, 543 

Valvula coli, 488 

processus vermiformis, 488 

Ventricles of brain, 339, 340, 362, 363 

Veins : 

azygos, 478 

- hemiazygos, 478 

- inferior caval, 503 

of head and neck, 206, 223 

- portal, 495, 497, 503 

- of rectum, 532 

Vesica urinaria. 524, 526, 540 
Vesicula seminalis, 524, 526, 527 



INDEX TO OLDER TERMS 



Abdominal ring, external, 
434 

- internal, 456 
Adam's apple, 194 
Alcock's canal, 450 
Ammon's horn, 342 
Anal fascia, 450 
Angle of Louis, 52 
Angulus Ludovici, 52 
Anterior carpal rete, 104 
Antrum of Highmore, 303 
Aortic opening, 421 

orifice, 412 

Aqueduct of Fallopius. 305 
Arch, deep palmar, 103 

- superficial palmar, 98 
Arnold's bundle, 358 

nerve, 270 

Arteria comes nervi phren- 
ici, 407 

fossae Sylvii, 321 

princeps cervicis, 235 
pollicis, 103 

- radialis indicls, 103 
Artery, Arteries : 

acromiothoracic or tho- 
racic axis, 04 

anastomotica magna. 78, 
82, 84 

of knee. 150 

- anterior choroidal. 320 

interosseous, 94, 
196, 105 

- radial carpal, 92 

ulnar carpal, 94 

- articular, of knee, 134 

- auditory. 320 

- azygos articular, 134 

- buccal, 262 

- collateral digital, 98 

cremasteric, 45S 

deep epigastric, 514 

dorsal interosseous, 106 

dorsalis scapulae, 64, 
<;<). 7:5 

external circumflex, of 
thigh. 1 is 

- malleolar. 160 

plantar, 178 

I)U( li,-. 140. 148, 451 

facial, 218, 252 

- first palmar interosse- 
ous. 103 

humeral thoracic. 58 

inferior dental, 262, 
264 

- internal articular, 
of knee, l',r> 

- i>.i!atine, 268, 2'.>r> 

profuncln, 7S. 84 

- internal circumflex, of 
thigh. MS 

iliac. r,M. .vjs 

malleolar. 160. 172 

plantar. 178 

- long thoracic. <>4 

middle capsular. .">i:> 

of the vas deferens, 
45S 

- palatine branch of as- 
cending pharyngeal, 295 

palmar digital. is 

posterior dental, 262 
Interosseous, 105 



Artery, Arteries : 

posterior meningeal 
branch of vertebral, 320 

radial carpal, 106 

scapular, 51 

ulnar carpal, 94 
rami intestini tenuis, 

474 

- ranine, 267, 317 

- sciatic, 127 

- second palmar interos- 
seous, 104 

small meningeal, 203, 
262 

superficial circumflex 
iliac, 451 

- superior intercostal, 
226 

profunda, 78, 84 

- thoracic, 63 

- suprascapular, 51, 73, 
214, 230 

- tonsillitic, 268 

transverse. .'520 

tympanic branch, of in- 
ternal carotid, 297 

Auditory nucleus, 354 
Auricles of heart. 412 
Auricular appendix, 412, 

413 
Auriculoventricular groove, 

413 
Azygos uvulae, 295 

Bicipital fascia, 82 
Bicuspid teeth, 290 
Bile canaliculi, 505 
Bowman's membrane, 378 
Brachial aponeurosis, 77 

- plexus, inner cord, 68 

outer cord, 68 
Bundle of Vicq d'Azyr, 361 

Callosomarginal fissure, 

336 
Canal, crural, 145 

inferior dental, 264 

- of Petit, 383 

- of Stilling, 382 

- posterior palatine, 303 

- Vidian. 297 
ranalis reuniens. .".'.M 
Capsule of Tenon, 276, 

277. 282 

Carpal joints, 111 
Cartilage of Santorini, 

::M 

Cerebellar peduncle, infe- 
rior, .".IT,. :::.:', 

- middle, '.Vll 

superior, :<27. 372 
Chordae Vullisi, ins 
Circumvallate, papillae, 

316 
Cistrnia l.asalis, 317 

magna, .'517 
Clarke's column. 246 
Coeliac axis. 4!M 
Column of r.urdach. 326 

,.r < ;.ii. :;-_'7 

or tract of Burdach, 
247 

of Goll, 247 



Columnae carneae, 421 
Conarium, 346 
Conjoined tendon, 454, 456 
Convolution, ascending 
parietal, 334 

- callosal, or gyrus for- 
nicatus, 336 

- hippocampal, 336 

occipitotemporal, 335 
Corpora Arantii, 423 
Cranial nerves. 202 
Cricothyroid membrane, 

224, 311. 312 
Crura cerebri, 322 
Crural canal, 145 

ring, 146 
Crus cerebri, 328 
Crypts of Lieberkuehn, 

485 
Cushion of epiglottis, 314 

Dentate fissure, or fissura 

dentata, 336 

Descemet's membrane, 379 
Direct cerebellar tract, 

365 

of Flechsig, 246, 

369 

Discus proHgerus, 546 
Duct of Bartholin, 266, 

267 
Ducts of Rivini, 266, 267 

Ensiform process, 52 
Epiphysis cerebri, 346 
External intermuscular 
septum, 78 

- of thigh, 142 

os, 544, 549 

Fallopian tube, 546, 550 
Fallopius, aqueduct of, 305 
False glottis, 309 

- vocal cords, 309 
Fascia lata, iliac portion 

of, 141 

- pubic portion of, 
141, ir,:; 

Fauces, anterior pillar of, 
291 

posterior pillar of, 291 
Fifth ventricle, 343 
Fissure of Rolando, 334 

- of Sylvius. 322 
Fold, arytaeno-epiglotti- 

dean. :;os 

- middle glosso-epiglotti- 
dean, 307 

Folds, lateral glosso-epi- 
glottldean, ::<s 

Foot" of cerebral pe- 
duncle, or pes pedun- 
culi. 358 

Foramen, inferior dental, 
261 

- ovale. 305 

of Winslow, 472 
Forceps major, 338, 343. 

364 

minor, 338, 364 
Fornix, anterior pillar of, 

343 

posterior pillar of, 343 

559 



560 



INDEX TO OLDER TERMS 



Fossa patellaris, 382 
Fov.-a hemielliptica. 392 

- hemisphaerica, 392 

Galen's loop, 313 
Ganglion commissurale, 
:;r,<> 

of Andersen, 270 

of Arnold, 299 
Gastrosplenic omentum, 

473 
Geniculate body, external, 

346 

internal, 346 

Gladiolus, 52 
Glands of Nuhn, 290 
Globus major, 460 

minor. 460 

Glottis respiratoria, 310 

- vera, 310 

vocalis, 310 
Gower's tract, 247 
Great horizontal fissure, 

328 

Ground-bundle, anterior, 
246 

- lateral, 247 
Gyrus dentatus, 337 

first temporal, 335 

- second temporal. 335 

third temporal, 335 

uncinate, 336 

Hesselbach's ligament, 456 
Hey's ligament, 141 
Hippocampus major, 342 

minor, 341 

Horn of Ammon, 342 

Ileocaecal valve, 487 

Iliac portion of fascia 

lata, 142 

Inferior peduncle, 369 
Infundibula of lung, 427 
Infundibuliform fascia, 

457 

Intercarotid gland, 222 
Intercostal membranes. 

399 
Internal capsule, anterior 

limb, 364 

posterior limb, 364 

- intermuscular septum, 

78 

- of thigh, 142 

os. 544, 549 
Iridocorneal angle, 334 
Ischiocapsular band, 155 
Iter e tertio ad quartum 

ventriculum, 328 

Jacobson's nerve, 271 
Joint, inferior radio-ulnar, 
114 
- tibiofibular, 184 

- superior radio-ulnar, 
114 

tibiofibular, 184 

- temporomaxillary, 262 
Joints, carpal, 111 
Jugular ganglion, 270 

Labyrinth of kidney, 509 
Laryngeal pouch or sac, 
309 

sinus. 309 
Laryngopharynx. 293 
Lenticular ganglion, motor 

root of, 280 

nucleus. :s<)4 

or ophthalmic ganglion, 
2 T o 

LI-SSIM-'S triangle, 218 
Ligamenta alaria, 181 

subflava, 286 



Ligament, Ligaments : 

- anterior annular, 93, 
100 

of leg, 157 

common, of spine, 
287, 430 

- costovertebral or 
stellate, 429 

- astragalonavicular, 
189 

calcaneocuboid, 189 

- calcaneonavicular, 189 

- chrondoxiphoid, 429 

coracobrachial, of 
Schlemm, 86 

costocolic, 472 

- cotyloid, 156 

external annular, of leg. 
157, 164 

lateral, of ankle, 186 
of elbow, 110 

of jaw-joint. 262 

of wrist, 112 

tarsal, 255 

- falciform, 552 

femoral, 141 

glenoid, 86 

- glenoideobrachiale in- 
ferius of Schlemm. 86 

- internum of 
Schlemm, 86 

great sacrosciatic, 125, 
450, 552 

Hesselbach's, 456 

- Hey's, 141 

- hyo-epiglottidean, 314 

- internal annular, at 
ankle, 170, 173 

lateral, of ankle. 186 

of elbow, 110 

of jaw-joint, 262 

- of knee, 165, 180 

of wrist, 112 

- tarsal, 255 

- long external, of knee, 
180 

- median puboprostatic, 
of Krause, 442 

odontoid or check, 288 

of Zinn, 279 

palmar intercarpal, 113 

- palpebral, 255 

posterior annular, 90, 
104, 106 

common, of spine, 
287, 430 

- occipito-axial, 287 
of knee, 180 

- pregleno-infrahumeral, 
of Faraboeuf, 86 

- pterygomaxillary, 291 

- pubocapsular or pubo- 
femoral, 155 

rhomboid, 225 

- small sacrosciatic. 553 

stylomaxillary, 217, 262 

- supraglenoprehumeral, 
of Farabceuf, 86 

- supraglenosuprahumer- 
al. of Farabffiuf, 86 

suspensory, of axis, 
288 

- thyro-arytaenoid, 312 

thyro-epiglottidean, 
o 14 

tibiofibular, 184 

- transverse superficial, 
08 

- triangular, 442, 448 
449 

true, of the bladder, 

- Y-shaped, of Bigelow, 
loo 

zonular or ring, 155 



Ligamentum jugale. 314 

mucosum, 181 

Limbic or falciform lobe, 

336 

Lumbosacral cord, 518 
Luschka's muscle, 456 

- tonsil, 293 

Lyra or lyre of David, 343 

Marsupial notch, 328 
Mediastinum, anterior, 
405 

- posterior, 424 
Meibomian glands, 255 
Membranous cochlea, or 

scala media, 394 
Muscle, Muscles : 

abductor pollicis, 103 

accelerator urinae, 439 

adductor magnus, upper 
part, 127, 153 

aryteno-epiglottidean, 
311 

attolens auriculam, 196 

attrahens auriculam, 
196 

azygos uvulae, 295 

brachialis anticus, 80 

- cervicalis ascendens. 
233 

- complexus. 229. 234 

crureus, 150 

- depressor alae nasi, 
250 

anguli oris, 250 

- labii iuferioris, 250 

ejaculator seminis, 439 

- elevator of lip, super- 
ficial, 250 

- of upper lip, deep, 
250 

erector clitoridis, 447 
penis, 438 

- spinae, 233 

extensor indicis, 105 
minimi digiti, 104 

ossis metacarpi pol- 
licis, 105 

primi internodii pol- 
licis, 105 

secundi internodii 

pollicis, 105 

external rectus, 279 

- inferior lingual, 316 

- levator anguli oris, 250 

scapulae, 229, 230 

- labii superioris, 250 

alaeque nasi, 
250 

- palati, 295 

- orbicularis palpebra- 
rum, 249 

- occipitofrontalis. 196 

palatoglossus, 295 

- palatopharyngeus, 295 

pronator radii teres, 93 

pyramic'alis nasi, 249 

rectus capitis anticus 
major, 284 

minor. 284 
- internus, 279 

labii, of Aeby, 251 

- retrahens auriculam, 
196 

- sacrolumbalis, 233 

semispinalis colli, 234 

serratus magnus, 68 

sphincter vaginae, 447 

- spinalis colli. 233 

- splenius colli, 231 

subcrureus, 152 

- superficial lingual, 316 

supinator brevis, 82, 
105 

longus, 93, 104 



INDEX TO OLDER TERMS 



561 



Muscle, Muscles : 

tensor palati, 295 

tarsi. 257 

- vaginae femoris. 
121). 150 
1 hyro-arytenoid, 311 

- thyro-epiglottidean, 
311 

- tibialis anticus, 158 

- posticus, 170 

- tracbelomastoid, 233 

transversal is cervicis, 
283 

- triangularis sterni. 4(2 

vastus externus. 15<> 

- interims. 150 
xygomat icus minor, 250 

Musculosplral groove, 82 

Nasopharynx, 293 
Nates, :J2S 
Nerve, Nerves : 

anterior crural, 142, 
148, 150 

- interosseous, 90 

superior dental, 298 

- tibial, 160, 105 

Arnold's, 270 

auditory, 201, 307. 324 

- circumflex, 64, 67, 68, 
71, 216 

collateral digital. 99 

- communicans fibularis, 
133, 166 

- tibialis, 132 

- crural branch of gen- 
itocniral. 1 12, 148, 516 

dorsal branch of ulnar, 
89 

cutaneous, 94 

external cutaneous, 125, 
1 ::.-,. 14-2, 148, 516 

laryngoal. 22 o 

- palatine, 296, 305 

- plantar, 178 

- popliteal, 133, 165 

- respiratory, of Bell, 
(17, 216 

- facial, pars intermedia, 
324 

genital branch of gen- 
it oc rural. 45S 

- genitocrural. 516 

- iliac branch of iliohy- 
pogastric. 452 

of last dorsal, 
452 

- inferior dental. 261 

maxillary, 254, 263, 
274 

- intercostohumeral, 60, 

74 

- internal cutaneous, 64, 

68, 76. 7s 

laryngeal. 220 

- plantar, 178 
popliteal. i:;2 

pudic. 12S 

saphenous. 1t;.~. 
last dorsal. 1L':; 

- lesser internal cutane- 
ous, or nerve of Wris- 
berg. 64. 6S. 76. 78 

loTig buccal. 255 

- malar branch of tem- 
pon. malar. 2S2 

median ]>almar cutane- 
ous. 96 

middle and internal 
cutaneous, 142 

or long subscapular. 
67 

superior dental. 298 
- musculocutaueous. 1 '',<>. 
165 



Nerve. Nerves : 

musculospiral, 64, 68, 
76. S2, 92 
nasal.' 277 

of Cotunnius, 301 

- orbital, 298 

- pars intermedia of 
Wrisberg, 201. .T24 

patellar branch of long 
saphenous, 142 

perineal branches of 
fourth sacral, 45O 

- petrosal, large, deep, 
297 

pneumogastric, 220, 
270, 324, 408, 425, 497 

- posterior interosseous, 
105, 108 

superior dental, 298 

- radial branch of mus- 
culospiral, 89, 92 

recurrent branch of in- 
ferior maxillary, 263 

- laryngeal. 270, 313 

- to the rhomboids, 51, 
67, 216, 230 

septa 1 branch of nasal, 
301 

short saphenous, 1(56 

- sixth, 280 

- small sciatic, 128, 130, 
133, 135, 136, 166, 447 

cutaneous 
branches of, 1 25 

spinal accessory, 201, 
214, 220, 324 

superficial cervical, 207 

superior maxillary, 254, 
274 

supraclavicular, 209 

suprasternal, 207 

- temporal branch of 
malar, 195 

of temporomalar, 
260, 261, 282 

temporomalar, 282, 298 

- third, 280 

tympanic branch of fa- 
cial, 306 

- Vidian, 297 

Nervus cerebralis III., 275 

- IV., 275 
V., 273 

- VI., 275 

patheticus. 275. 276 
Nucleus of Burdach's col- 
umn. 348 

of Goll's column, 348 

of sixth nerve, 354 

of III. nerve. 357 

polyposus, 430 

Optic lobes, 328 

radiation. 364 
Oral pharynx. 2!):; 
Orbicular ligament, 115 
Organ of Giraldes, 462 

Pacchionian bodies. 317 

granulations. IMS 
1'cs hippocampi. .". 12 

I 'i liars of the iris, 380 

1'inna. 258 

Pituitary body, 203, 322, 

338 

Plexus gulae. 42f, 
Pomiim Adami. P.I 1 
Posterior carpal rete. 106 

- longitudinal bundle, 
:;:,4. 857 

Prel racheal fascia. 2<'.i 
Pubic portion of fascia 
lata, 1112 

Pulmonary orifice. 4 1 2 

86 



Pyramid of Ferrein, 509 
Pyramidal tract, crossed, 

246 
direct, 246 

Receptaculum chyli 514 
Recessus infundibulifor- 

mis, 293 
Reniculi, 508 
Respiratory bundle, 348 
Rete, anterior carpal, K>4 
Ribbon of Reil, .",27 

Saphenous opening, 140 
Scarpa's triangle. 122, 146 
Sclerotic coat, or white of 

the eye, 378 
Semilunar fascia, 80 

- fibrocartilages of knee, 
181 

notch, 328 

Sensory decussation of me- 
dulla oblongata. .'552 

Septum, anterior peroneal, 
158 

- posterior peroneal, 158 
Shoulder-joint, accessory 

ligament of, 85 
Sigmoid flexure, 486 

notch, 261 

Sinus alae parvae, 202 

- basilar, 203 

inferior longitudinal, 
199, 202 

- lateral, 202 

pyriformis, 294 

- superior longitudinal, 
202 

Socia parotidis, 252, 290 
Sphenoidal fissure, 275, 

280, 297 
Spheoomaxillary fissure, 

282 

- fossa, 303 

Spinal cord, anterior col- 
umn of, 243 

horn of, 245 
- lateral column of, 
243 

- horn of, 245 
posterior column of, 
243 

horn of, 245 

Steno's duct, 290 

Stria fornicis or stria 

pinealis, 346 
Subclavian triangle. 214 
Subthalamic nucleus, 360 

- region, 338 
Sulcus, callosal, 336 

callosomarginal, 334 

- intraparietal, of Tur- 
ner. :::;.") 

- limiting, of Reil, :?."> t 

occipitotemporal, 3 .".5 

- parallel, or first tem- 
poral. :::::. 

second temporal, 335 
Superficial arcuate fibres, 

827 
Supra-acromial branches, 

69 
Suprasternal notch, 52 

Taenia semicircularis. 341 
Test is. 828 
Thoracic axis, 55 
Thyrohyoid membrane, 

222. 310 

Transverse fascia. 455 
Triangular fascia of the 

abdomen. 457 
tibroc.-irt ilaire. 1 15 
ligament. 442. 44S. 449 
Trigonum ventriculi. .". 2 



562 



INDEX TO OLDER TERMS 



Torcular Herophili, 202 
Tubercle of Rolando, 327 
Tunica Ruyschiana, 379 
Turbinated bones, 301 
Turk's bundle, 358 

Valve of Houston. 536 
of Vieussens, 328 
Valvulae conniventes, 484 
Vein, Veins: 

azygos major, 408, 412, 
428 

minor superior, 429 



Vein, Veins: 

external pudic, 148 

saphenous, 166 

great cardiac, 414 

inferior dental, 262 
- internal iliac, 514 

saphenous, 140, 142, 

148, 165, 166 

of corpus striatum, 341, 
344 

of Galen. 344 

of Verheyn, 508 

suprascapular, 215 



Velum interpositum, 343 
Venae Thebesii, 414 
Vesical layer of fascia en- 

dopelvina, 523 
Vidian canal, 297 
nerve, 297 

Wharton's duct, 290 
White line of pelvic fas- 
cia, 450, 520 
Wisdom tooth, 290 
Womb, 543 
Wrist-joint, 111 



INDEX TO NEW TERMS 



Abdomen, 42 

contents of, 462 
Accessory lemniscus, 367, 

373 

Acromion, 41 
Aditus laryngis, 308 
Adminiculum lineae albae, 

456 
Aequator bulbi. 376 

- lentis, 383 
Agger nasi, 302 
Ala cinerea. 331 

lobuli centralls, 330 
Alae nasi, 193 
Alcock's canal, 450 
Alveoli pulmonis, 427 
Amphiarthroses intercar- 

peae, 111 

Ampulla ductus deferen- 
tis, 52. S 

lacrimalis, 257 

recti, 524 

- tubae uterinae [Fallo- 
pii], 547 

Ampullae membranaceae, 
394 

- osseae. 392 
Anal canal. 536-548 
Anastomosis around ankle, 

160 

elbow, 80, 105 

- knee, 134 
Angle of Louis, 52 
Angular gyrus, 335 
Angulus iridis, HS4 

- oculi (lateralis. medi- 
alisi. 247 

Annulus conjunctivae, 378 

femoralis, 146, 511 

fibrocartilagineus (mem- 
bran, tympani), 388 

fibrosi (cordis), 424 

- fibrosus (fibrocartilagi- 
nis intervertebralis, 286, 
430 

- haemorrhoidalis, 536, 
548 

inguinalis abdominalis, 
456 

subcutaneus, 436. 452 

iridis (major, minor), 
384 

ovalis, 117 

- tendineus communis 
(Zinni). 279 

uretb rails. r,.",7 
Ansa duodenal is. 463 

- hypoglosal, _-i>. ur,9 

Intestlnalla, 463 

lenticularis, 302 

peduncularis, 362 
sTibrlavia [Vieussenii], 

227. 272 

- umbilicalis. 463 
Anterior commissure of 

vulvn. 444 

fornix of vagina. .".4." 

intercostal arteries. 402 
- interosseons nerve of 

forearm, 96 

marginal bundle, 365 

median line, 42 

mediastinum. 406 

pyramid, 326 



Anterior tibiofibular com- 
partment of leg, 168 

triangle of neck, 216 
Antbelix, 259 
Antibrachium, 41 
Anticubital fossa, 80 
Antitragus, 258 
Antrum pyloricum, 448 

tympanicum, 386 
Aorta, 409, 422, 424, 426, 

512. 513 

abdominalis, 513 

ascendens, 422 

- descendens, 409, 524 

thoracalis. 422. 426 

ramus visceralis, 426 
Aortic opening in dia- 
phragm, 511 

valve. 421, 423 
Apertura lateralis ventric- 

uli quarti, 331 

- mediana ventriculi 
quarti, 331 

tympanica canaliculi 
chordae, 386 

Apex cartilaginis arytae- 
noideae, 314 

columnae posterioris, 
145 

cordis. 412 

linguae. 316 

nasi. 193 

prostatae, 527 

pulmonis. 408 

- supra renal is (gl. dex- 
trae), 509 

Aponeurosis, brachial, 60, 
77 

of external oblique, 454 

- M. obliqui externi ab- 
dominis. 454 

palmaris, 97. 98 

plantaris, 157. 173, 176 

- urogenitalis. 505 
Appendices epiploicae. 486 
Appendix fibrosa hepatis. 

504 

testis [Morgngniil. 462 

- ventriculi laryngis. 309 

vesiculosa [Morgagnii], 
546 

Aquaeductus cerebri [Syl- 

vii|. 328 
Arachnoidea encephali, 

198. 317 

- spina'is. 238. 239 
Arachnoideal villi, 198, 

317 
Arbor vitae cerebelli. .",.">."> 

of uterus, 549 
Arcuate fibres. 364 
Arcus aortae, 409. 422 

(arteriosus) plantaris, 
178. 179 

- rami perforantes. 
178 

- cartilaginis cricoideae, 
314 

- costarum. 399 

Inmbocostalis lateralls 
rHalleril. 511 

medialis. 511 

- M. solei. 169 

tarseus, 279 



Arcus tarseus inferior, 279 

superior, 279 

- tendineus fasciae pel- 
vis, 521, 541 

- M. levatoris ani, 
520, 541 

venosi digitales, 89 

venosus dorsalis pedis, 
156 

plantaris, 176 

- volaris (arteriosus) 
profundus, 103 

superficialis, 102 
Area acustica, 331 

cochleae, 393 

nervi facialis, 393 

parolfactoria [Brocae], 

OO I 

- vestibularis inferior, 
394 

superior, 393 
Areola mammae, 42 
Arnold's nerve, 270 
Arteria, Arteriae : 

acetabuli, 528 

alveolares superiores 
anteriores, 298 

alveolaris inferior, 262, 
264 

ramus mylohyoideus, 
262, 264 

- superior posterior, 
262 

- raml gingivales 
superiores, 262 

angularis, 252 

anonyma, 224, 442 

appendicularis, 474 

arciformes renis, 506 

arcuata, 160 

auditiva interna, 320 

auricularis posterior, 
195. 218 

- profunda, 261 

axillaris, 63, 65, 66, 73, 
78 

basilaris, 201. 320 
rami ad pontem. 320 

- brachialis, 78, 79, 82 

bronchiales, 409. 426 

- buccinatoria, 262 

bulbi urethrae. 443, 529 

vestibuli (vaginae), 
448, 531 

- carotis communis, 220, 
282, 422 

externa, 218, 220. 
252, 268 

interna, 200, 203, 
220. 268. L'7. 1 :. 297. 320 

- ramus caroticotym- 
panicus. 297 

centralis retinae, 278 

cerebelli Inferior ante- 
rior, 320 

posterior, 320 
- superior, 320 

cerchri anterior. 320 
ini'diM. 320 

posterior. 320 
ccrvicnlis ascendens, 

'_"_'6. 2:55. 242 

rami musciilares, 
235 

563 



564 



INDEX TO NEW TERMS 



Arteria, Arteriae : 

cervicalis ramus pro- 
1'undus, 235 

rami spinales, 238, 
242 

profunda, 226, 235 

superficial, 226, 

229, 230 

chorioidea, 320 

ciliares anteriores, 278 

pos^eriores. 27S 

circumflexa femoris lat- 
eralis, 148 

- ramus as- 
cendens, 129 

medialis, 127, 
148, 153 

profundus, 153 

- acetabuli, 153 

superficialis, 153 

humeri anterior, 64, 
71 

posterior, 64, 69, 
71 

ilium profunda, 514 

superficialis, 140, 
148, 451 

scapulae, 64, 70, 72, 
73 

- clitoridis, 448, 531 

- coeliaca, 490, 491, 513 

colica dextra. 474 

media, 474 

sinistra, 476, 477 

- collateralis media, 84, 
105 

radialis, 84. 105 

ulnaris inferior, 68, 
82, 84, 105 

superior, 68, 84, 
105 

- comitans ischiadici, 
127. 128 

- communicans anterior, 
320 

posterior, 320 

conjunctivales (ante- 
riores, posteriores). 278 

coronaria (cordis) 
dextra. 413, 422 

- ramus descendens 
posterior, 413 

- (cordis) sinistra, 
413 

- ramus circumflexus, 
413 

- descendens an- 
terior. 413 

cystica, 476, 490 

deferentialis, 458. 529 

digitales (manus) dor- 
sales. 90, 106 

plantares, 178 

- volares communes, 
08 

- propriae. 98 

dorsalis clitoridis, 448, 

- indicis, 106 
nasl. 279 

- pedis, 160 

- ramus plantaris 
profundus, 1 60 

penis. 443. 541 

epigastrica inferior. 
140, 454, 456. 514. 527 

- ramus obturatorius, 
>1 1 

superficialis, 148, 

superior, 402, 454 

eplsclerales. 278 

ethmoidalis anterior, 
278 

posterior, 279 



Arteria, Arteriae : 

femoralis, 145, 148, 149, 
154 

rami inguinales, 140, 

148 

musculares, 148, 
149 

frontalis, 195, 279 

gastrica dextra, 490 

- sinistra, 476, 492, 
513 

rami oesophagei, 
492 

gastricae breves, 492 

gastroduodenalis, 490 

gastro-epiploica dextra 
and sinistra, 490, 492 

rami epiploici, 490 

genu inferior lateralis, 
134 

medialis, 134, 165 

media. 134 

superior lateralis, 
134 

medialis, 134 

suprema, 149, 150 

rami articulares, 
150 

musculares, 
150 

ramus saphenus, 150 

- glutaea inferior, 127, 
528 

superior, 126, 528 

ramus inferior, 
126, 528 

superior, 126, 

528 

- haemorrhoidalis infe- 
rior, 450, 529 

media. 529 

- superior, 476, 477, 
530. 532 

- hepatica, 476, 490, 492, 
513 

propria, 490 

- ramus dexter, 476, 
490 

sinister, 490 

hypogastrica, 514, 528 

- ileae, 474 

- ileocolica, 474 

iliaca communis, 513 

externa, 514, 527 

iliolumbalis, 242, 528 

ramus iliacus, 528 
lumbalis, 528 

spinalis, 242, 528 

- infraorbitalis, 298 

- intercostales. 242, 399, 
400. 401, 426, 428 

intercostalis suprema 
226. 242, 401 

- interlobulares renis. 506 

interossea communis, 94 

dorsalis, 94, 105 

recurrens, 105 

- volares, 94. 96, 105 

intestinales. 474 

jejunales. 474 

- labiales posteriores, 
447. .",-_'!) 

labialis inferior, 252 

superior, 252 

laorimalis. 278 

- laryngea inferior, 202, 
311, 313 

- superior, 220 ^5^ 
310. 313 

- lienalis. 472, 513 

rami lienales. 492 

pancreatici. 492 
- Jig. teretis uteri. 514 

-lingualis, 218, 220, 267, 
o!7 



Arteria, Arteriae : 

- lingualis rami dorsales 
linguae, 267, 317 

ramus hyoideus, 220 

lumbales, 242, 513 

ramus dorsalis, 513 

spinalis, 238, 242, 
513 

lumbalis ima. 513. 532 

malleolaris anterior lat- 
eralis, 160 

meclialis, 160 

posterior lateralis 
172 

medialis. 172 

mammaria interna, 226, 
402, 407 

rami intercostales, 
402 

- perforantes, 55, 
399, 402 

rami sternales, 402 

marginalis lateralis, 157 

- medialis, 157 

masseterica. 261, 262 
- maxillaris externa, 218, 

2*?0 '>."">;_! 

rami glandulares, 
218 

ramus tonsillaris, 
218 

maxillaris interna, 252, 
261. 268 

mediana, 96 

- mediastinales ante- 
riores, 407 

meningea anterior, 203 

- media, 198, 203, 262, 
273 

ramus meningeus ac- 
cessorius. 203, 262 273 

pptrosus super- 
ficialis, 27., 

meningea posterior, 203, 
268 

mentalis, 264 

mesenterica inferior, 
477, 513 

superior, 474, 513 

metacarpeae dorsales, 
90, 106 

- volares, 98. 103. 104 

metatarseae dorsales, 
160 

plantares, 178 

musculophrenica, 402 

- nutric'a femoris infe- 
rior, 136 

superior, 136, 152 
fibulae, 172 

nutriciae humeri. 84 

nutricia tibiae, 172 

obturatoria, 154, 528 

ramus anterior, 154, 
528 

posterior, 154, 
528 

pubicus. 528 

- occipitalis. 196. 203, 
214, 220, 230, 235, 268. 
269 

ramus meningea, 203 

musculares, 235 
descendens, 235 

mastoideus. 235 

oesophageae. 426 

- ophthalmica, 203, 273. 
278 

rami musculares, 278 

ovarica, 513, 542 

palatina ascendens, 218, 
268, 295 

descendens, 295 

- palpebrales laterales, 
278 



INDEX TO NEW TERMS 



565 



Arteria, Arteriae : 

meuiales. 27!> 

pancreaticoduodenales, 
inferior et superior, 474, 
490 

- rami duodenales, 
41)0 

pancreatici, 490 

penis, 443, 52!) 

- pcrl'orans prirna, 136, 

1 52 

secunda, 136, 152 

- tertia, 136, 152 

- pericardiacophrenica, 
407, 408 

perinei, 439, 446, 529 

peronaea, 172 

- rami calcanei later- 
ales, 172 

communicantes, 
172 

ramus perforans, 172 

pharyngea ascendens, 
2<>3. 220, 268 

rami pharyngei, 268, 
295 

phrenica inferior, 513 

rami suprarenales 
superiores, 513 

phrenicae superiores, 
426 

plantaris lateralis, 178 

- medialis, 178 

ramus profundus, 
178 

superflcialis, 178 

- poplitea, 133 

- profunda brachii, 78, 
80, 82, 84 

ramus deltoideus, 
84 

- clitoridis, 448 

femoris, 136, 148. 
152 

- linguae, 267, 317 
penis, 443, 52!) 

- pudenda interna, 126, 
450. 529 

pudendae externae, 140, 
148. 451 

pulmonalis, 409, 417, 
423. 428 

- ramus dexter, 409, 
417 

sinister. 409, 417 

radialis, 74, 82, 90, 106 

- ramus carpeus dor- 
snlis, 106 

volaris, 92 

- volaris super- 
ficial is. 92 

recurrens radialis, 92, 
105 

tibialis anterior, 160 

- ulnaris, 82, 94, H>5 

renal is. 5<)<>. 513 

- sacrales laterales, 242, 
528 

- rami spinales, 242, 
528 

sacralis media. 513. 532 

postcriorcs. 4.'!!), 529 

Bigmoideae, 477 

spermatica externa, 
45S. 514 

- interna, 458. 513 

spinalis anterior. 242, 
81$ 

- posterior. 242. 319 

sternocleidomastoidea, 
220 

snhclavia. 63. 226. 422 

sublingualis, 267 

submciitnlis. 218 

subscapularis, 64, 73 



Arteria, Arteriae : 

supraorbitalis, 195, 279 

- suprarenales, inferior 
and media, 51:; 

- surales, lateralis and 
medialis, 134 

tai-sca hilci-alis. 160 

tarseae mediales, 160 

- temporales profundae, 
anterior and posterior, 
2(51, 262 

- temporalis media, 252, 
2(!0 

- superficialis, 195, 
252, 260, 268 

ramus frontalis, 195 

parietalis, 195 

testicularis, 513 

thoracalis lateralis, 55, 
61, 64, 68 

- rami mammarii 
externii, 55, r>4 

suprema, 63 

thoraco-acromialis, 64, 
65, 70 

rami pectorales. 65 

ramus acromialis, 
65, 70, 71 

deltoideus. 65, 70 

thoracodorsalis, 64 

- thymicae, 407 

thyreoidea ima (Var.), 
224, 422 

inferior, 226 

superior, 220, 222 
ramus hyoideus. 220 

sternomastoideus, 
220 

cricothyreoi- 
deus, 224 

tibialis anterior. 160 
posterior. 172 

rami calcanei me- 
diales, 172 

fibularis. 172 

transversa colli, 73, 214, 
226 

- ramus descen- 
dens, 230 

faciei, 252 
scapulae, 73, 226, 

229, 230 

tympanica anterior, 261 
inferior, 268 

superior, 273 

ulnaris. 82. 92, 84 

- ramus carpeus dor- 
salis. 94 

volaris, 94 

umbilicales. 529 

urethalis, 443, 448, 529, 
531 

uterina, 529. 542 

ramus oyarii, 542 

tubarius. 542 

- vasinales. 529. 542 

vertebralis, 201, 203, 
226. 2 35. 242. 284, 

810 

- rami spinales. 238, 
242. 284 

- ramus meningeus, 
203 

- vosicales superioros. 529 

vesicalis inferior. 529 

- /ys;(>matico-orbit:tlis. 
262 

Arterial circle of Willis. 
320 

crucial anastomosis. 127 
Arteries, facial, 218, 220, 

252 

obliterated hvpogastric, 
514. 52S 

Arteriolae retinae, 381, 382 



Articulatip, Articulationes : 

acromioclavicularis, 71 

- atlanto-epistrophica, 
287 

- atlanto-occipitalis, 237 

calcaneocuboidea, 175, 
188 

capitulorum (costa- 
rum), 429 

- carpometacarpea polli- 
cis, 115 

- carpometacarpeae, 115 

costotransversariae, 429 

costovertebrales, 429 

coxae, 156 

cricoarytaenoidea, 315 

cricothyreoidea, 314 

cubiti, 109 

cuneonavicularis, 188 

- digitorum (manus), 
116 

- pedis, 190 

- et ligamenta capitis, 
286 

- cinguli extremi- 
tatis inferioris, 552 

superioris, 

71, 225 

genu, 180 

humeri, 84 

humeroradialis, 110 

humero-ulnaris, 110 

- incudomalleolaris. 390 

incudostapedia, 390 

- intercarpea. 115 

interchondrales, 429 

- intermetatarseae, 190 

intertarseae. 187 

intervertebrales, 430 

- mandibularis, 262 

manus. 111 

- metacarpophalangeae, 
116 

metatarsophalangeae, 
175 

ossiculorum auditus, 
390 

- ossis pisiformis, 113 

- pedis, 109 

- radiocarpea, 111 

- radio-ulnaris distalls, 
110, 114 

- proximalis, 110, 114 

sacroiliaca. 553 

scapulohumeralis. 84 

- sternoclavicularis. 225 

- sternocostales. 429 

- talocalcanea, 175. 187 

- talocalcaneonavicularis, 
1S7. 1SS 

talocruralis. 185 

talonavicularis. iss 

- tarsi transversa < fho- 
parti), 122, 187 

- tareometataroeae, 175 

- tibiofibularis. 184 
Articulation, Articula- 
tions : 

of atlas, axis, and occi- 
pital bone, 287 

- capitular, 429 

costo-transverse. 429 

costo-vertebral. 429 

crico-arytaenoid. .",15 

ciicothyreoid, 314 

of the foot, 185 

- Interchondral. 429 

intervertebral. 430 

manubrio-gladiolar. 429 

sternoclavicular. 225 

sternocostal. 429 

temporomaxillary. 262 

- thorax. 429 
Arytaenoid cartilages. 314 
Ascending fibre system, 365 



566 



INDEX TO NEW TERMS 



Association fibre systems, 

373 

Atrium cordis, 412 
dextruin, 412 
- sinistrum, 413, 418 
Auditory apparatus, 384 

ossicles, 388 

ligaments of, 390 

Auricle, left, 413, 418 

ligaments of. 259 

right, 412, 415, 416 
Auricula cordis dextra, 

412, 415, 416 

sinistra, 413, 418 

Auriculae, 193 
Auricular cartilage, 260 
Auriculoventricular 

groove, 413 

orifice, 412 
Auris externa, 258 

- interna, 384 

media, 384, 385 
Axilla, 41 

Axis lentis, 383 

oculi (externa, interna), 
376 

optica, 376 

Bartholin, duct of, 447 
Bartholin's glands, 447 
Basal ganglia of cerebral 

hemispheres, 364 
Basilar sinus, 203 
Basis cartilaginis arytae- 

noideae, 314 

cochleae, 392 

cordis, 412 

encephali, 318 

modioli, 392 

pedunculi, 358 

prostatae, 527 

pulmonis, 408 

pyramidis (renis), 508 

stapedis, 389 
Bell, nerve of, 67 
Bertin, columns of, 508 
Bifurcatio tracheae, 424 
Bile ducts. 489 

Bipolar cells of retina, 366 
Bladder, urinary, 505, 525, 
537, 543, 549 

in distended condition, 
527 

In empty condition, 527 

orifices of, 537 

- trigone of, 537 

Body of clitoris, 444, 448 

of the penis, 435 

of testicle, 459 
Brachial aponeurosis, 60, 

^plexus, 66, 67, 215, 216, 

Brachium, 41 

conjunctivum, 327 
Brain, base of, 331 

preservation of. 201 

removal of, 201 
Broca. convolution of, 334 
Bronchioli. 427 

respiratorll, 427 
Bronchus (dexter, sinis- 

ter), 424 

Brunner's glands. 494 
Bucca. 288 
Buccal glands. 290 
Buccopha ryngpRl fascia, 

-'51. 2(51. 201 
Bulb of the penis. 440 

of the vestibule. 447 
Bulbus aortae, 41'L! 

cornu posterioris. 341 

oculi. 193. 280. 375 

olfactorius, 337 

pontis, 327 



Bulbus quadrigeminum in- 
ferius, 328 

superius, 328 

urethrae, 440 

V. jugularis inferior, 
226 

- venae jugularis supe-