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COMPEND
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COMPENDS
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HUMAN ANATOMY. 8th Edition. 16 Plates, 139
Text Illustrations. By S. O. L. Potter, M. D.
Revised by D. G. Metheny, M. D.
PHYSIOLOGY. i6th Edition. 27 Illustrations. By
A. P. Brubaker, M. D.
OBSTETRICS. loth Edition. 80 Illustrations. By
H. G. Landis, M. D. Revised by Dr. Clifford
B. Lull, M. D.
MATERIA MEDICA, THERAPEUTICS AND PRESCRIPTION
WRITING. 9th Edition. Accord with U. S.
Phar. X. By S. O. L. Potter, M. D. Revised
by A. D. Bush, M. D.
GYNECOLOGY. 5th Edition. 167 Illustrations. By
Wm. H. Wells, M. D. Revised by W. G. Harer,
M. D.
DISEASES OF THE EYE AND REFRACTION. 4th Edition.
109 Illustrations. By G. M. Gould, M. D. and
W. L. Pyle, M. D.
SURGERY. Bandaging and Minor Surgery. 185 Illus-
trations. By Benjamin Lipshutz, M. D.
MEDICAL CHEMISTRY. 7th Edition. By Henry Leff-
mann, M. D. and Max Trumper, A. M.
PHARMACY. loth Edition. Based upon Remington's
Pharmacy, U. S. Phar. and U. S. Formulary. By
F. E. Stewart, M. D. Revised by H. W.
Youngken, M. D.
DISEASES OF THE SKIN. 7th Edition. 119 Illustra-
tions. By J. F. Schamberg, M. D.
GENITO-URINARY DISEASES AND SYPHILIS. 4th Edi-
tion. 44 Illustrations. By C. S. Hirsch, M. D.
BACTERIOLOGY. 4th Edition. 86 Illustrations. By
R. L. Pitfield, M. D.
P. BLAKISTON'S SON & Co. Philadelphia
POTTER'S
C O M P E N D
OF
HUMAN ANATOMY
REVISED BY
D. GREGG METHENY
M. D., L. R. C. P. AND S. (EDTN.), L. F. P. S. (GLASGOW)
ASSOCIATE IN ANATOMY, JEFFERSON MEDICAL COLLEGE, PHILADELPHIA
EIGHTH EDITION
WITH 139 ILLUSTRATIONS; ALSO NUMEROUS TABLES AND
16 PLATES OF THE ARTERIES AND NERVES
PHILADELPHIA
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COPYRIGHT, 1915, BY P. BLAKISTON'S SON & Co.
PRINTED IN U. S. A.
BY THE MAPLE PRESS COMPANY, YORK, PA.
PREFACE TO THE EIGHTH EDITION
After many years of wandering in the embryological minutiae of " trans-
cendental anatomy," it has at last become apparent to most teachers and
examiners in anatomy that the only kind of anatomy that could be of any
practical value to a physician or surgeon, as such, is the anatomy that
can be actually seen and handled. Consequently in this text, details of
embryology, histology, and physiology have been largely left to the text-
books dealing with those subjects, in order that gross human anatomy
might be the more thoroughly explained.
While all of the "recognized authorities" and the publications of the
various anatomical associations have been freely consulted, these descrip-
tions have been based entirely on the actual facts to be found in the human
body and are not dominated by any one single authority. The many new
discoveries and the changes in teaching methods that have been made in
recent years, have made it necessary to make so many additions and
changes in the text that the entire work had to be rewritten. Parts of
the nomenclature of the German Anatomical Society are now being used
so universally, that it became necessary to include it, in its entirety, in
the Latin form. However, since comparative anatomy has been almost
entirely ignored in the B.N.A., and as so many of its terms are not only
inconsistent but also evidence personality rather than broad anatomical
principles, it seems certain that it still requires much revision if it is to
endure; therefore while the B.N.A. terms are given in the Latin form,
only such of them as seem entitled to survival are given in the English
form in preference to the older regular terms.
It is confidently hoped that the student will find these descriptions
not only accurate and up-to-date, but intelligible as well.
D. GREGG METHENY.
4609 SPRUCE ST., PHILADELPHIA.
•2.112.2,
PREFACE TO THE SEVENTH EDITION
The twenty years which have elapsed since this compend was first
issued have brought many changes of nomenclature and description
into the teaching of Anatomy. The present edition has been entirely
re-written and brought into harmony with the latest text-books on this
subject. The text has been expanded wherever greater detail seemed
desirable, but in so doing the condensed form of statement heretofore
adopted has been carefully followed. The total number of illustrations
has been increased from 117 to 138, and many of the cuts used in former
editions have been replaced by newer ones. The Tables and Plates,
heretofore published in an appendix, have been thoroughly revised,
and are now placed in their natural positions in the text. These changes
have increased the size of the volume by 82 pages, and have made it
practically a new book, which the author hopes will receive a continu-
ance of the favor heretofore extended to the previous editions.
Originally designed for the use of the medical student in preparing
for the exercises of the quiz-room and for his examinations, the text is
confined to the essentials of each structure treated of, which are arranged
in such a manner as to facilitate their rapid acquirement. All super-
fluities of description have been studiously avoided, and only such matter
inserted as should be thoroughly known in order to pass a rigid examina-
tion on any organ or structure of the human body. The descriptions will
be found to closely follow Gray, though Morris, Quain, and other recog-
nized authorities have been freely consulted during the preparation of
the text. For many of the special arrangements the author is indebted
to the lectures of Professor W. H. Pancoast, formerly of Jefferson Medical
vii
Vlll PREFACE TO THE SEVENTH EDITION
College, and to the quizzes of Dr. Henry Morris, at one time assistant
to the chair of Anatomy in the same school.
While striving to carry out the object of this series in furnishing the
medical student with a condensed manual of Anatomy, the author has
endeavored, from a strong appreciation of the importance of the subject,
to make this volume deserving of first rank among its kind; and believing
that a judicious condensation, which does not slight the essential features
of the subjects treated, cannot fail to be of benefit in any department
of science, he again commits this compend to the teachers and students
of Anatomy, in the hope that it may continue to be found worthy of a
place alongside the more exhaustive and exhausting text-books.
SAM'L O. L. POTTER.
CONTENTS
FACE
OSTEOLOGY i
BONES OF THE TRUNK. . . . 5
VERTEBRAL COLUMN 5
THORAX 7
PELVIS 9
BONES OF THE HEAD 14
ORBITS 35
FOSSAE 37
SUTURES AND FONTANELLES 39
FORAMINA AT THE BASE OF THE SKULL 41
POINTS AT THE BASE OF THE SKULL 44
BONES OF THE UPPER EXTREMITY 44
OF THE SHOULDER 44
OF THE ARM 47
OF THE FOREARM 48
OF THE HAND 50
BONES OF THE LOWER EXTREMITY 52
OF THE THIGH 52
OF THE LEG 54
OF THE FOOT 56
ARTICULATIONS 58
ARTICULATIONS OF THE TRUNK 60
OF THE UPPER EXTREMITY .* 64
OF THE LOWER EXTREMITY 68
MUSCLES AND FASCIAE 73
MUSCLES OF THE HEAD 75
OF THE EAR 79
OF THE NECK 80
ix
X CONTENTS
PAGE
OF THE LARYNX AND EPIGLOTTIS 85
OF THE BACK 86
OF THE THORAX 93
OF THE ABDOMEN 95
OF THE PELVIC OUTLET 97
OF THE PERINEUM 98
OF THE UPPER EXTREMITY 99
OF THE LOWER EXTREMITY 107
FASCIA OF THE HAND 105
LUMBO-DORSAL 90
OF THE ILIAC REGION 107
OF THE THIGH 108
OF THE FOOT 115
THE BLOOD-VASCULAR SYSTEM 118
HEART 118
ARTERIES 122
PULMONARY ARTERY AND AORTA 122
ARTERIES OF THE HEAD AND NECK 124
CIRCLE OF WILLIS 128
TRIANGLES OF THE NECK 128
ARTERIES OF THE UPPER EXTREMITY 130
OF THE TRUNK 136
OF THE LOWER EXTREMITY 141
ARTERIAL ANASTOMOSES 145
TABLES AND PLATES OF THE ARTERIAL SYSTEM . 147
VEINS OF THE HEAD AND NECK 163
OF THE UPPER EXTREMITY 166
OF THE THORAX 167
OF THE LOWER EXTREMITY, PELVIS AND ABDOMEN. . . . 168
OF THE HEART 171
THE LYMPHATIC SYSTEM 171
LYMPHATICS OF THE HEAD AND NECK 172
OF THE UPPER AND LOWER EXTREMITIES 173
OF THE PELVIS, ABDOMEN, INTESTINES, THORAX . . . .174
CONTENTS XI
PAGE
THE NERVOUS SYSTEM 175
BRAIN 178
MENINGES 180
CEREBRUM 183
CEREBELLUM 206
MEDULLA OBLONGATA 208
NERVE-TRACTS IN THE BRAIN 212
SPINAL CORD 213
NERVE-TRACTS IN THE SPINAL CORD 214
CRANIAL NERVES 216
GANGLIA OF THE CRANIAL NERVES 223
SPINAL NERVES .' 226
CERVICAL NERVES 227
THORACIC NERVES ' 231
LUMBAR NERVES 232
SACRAL AND COCCYGEAL NERVES 233
SYMPATHETIC SYSTEM 236
GANGLIATED CORD 237
GREAT PLEXUSES 239
TABLES AND PLATES OF THE NERVOUS SYSTEM. . 243
ORGANS OF SPECIAL SENSE 270
SKIN 270
APPENDAGES OF THE SKIN . 272
TONGUE 273
NOSE 276
EYE 280
SCLEROTIC AND CORNEA 281
CHOROID, CILIARY BODY AND IRIS 283
RETINA 285
MUSCLES AND NERVES OF THE EYEBALL 289
VESSELS AND NERVES OF THE EYE 289
APPENDAGES OF THE EYE 293
EAR 296
EXTERNAL EAR 297
MEMBRANA TYMPANI 298
Xll CONTENTS
PAGE
TYMPANUM 300
EUSTACHIAN TUBE 303
INTERNAL EAR 304
AUDITORY NERVE 310
ORGANS OF DIGESTION 312
MOUTH • • 312
PALATE AND TONSILS 313
SALIVARY GLANDS 315
TEETH 317
PHARYNX . . '. 320
(ESOPHAGUS - 322
ABDOMEN 323
PERITONEUM 325
STOMACH 328
SMALL INTESTINE 33o
LARGE INTESTINE 333
LIVER 336
STRUCTURE . . .' 339
VESSELS 341
EXCRETORY APPARATUS. 342
PANCREAS 343
LESSER PANCREAS 344
DUCTLESS GLANDS 344
THYROID AND THYMUS GLANDS 345
SPLEEN 348
ORGANS OF VOICE AND RESPIRATION 350
LARYNX 350
TRACHEA AND BRONCHI 355
PLEURAE 356
MEDIASTINUM 356
LUNGS 357
THE URINARY ORGANS . . 360
CONTENTS Xlll
PACE
KIDNEYS 360
URETERS 363
SUPRA-RENAL CAPSULES 364
BLADDER 365
MALE URETHRA 368
FEMALE URETHRA 37°
THE MALE ORGANS OF GENERATION 370
URETHRAL GLANDS IN THE MALE 370
PENIS 37i
TESTES 372
APPENDAGES OF THE TESTES 375
THE FEMALE ORGANS OF GENERATION 377
VULVA 377
VAGINA 379
UTERUS 380
APPENDAGES OF THE UTERUS 382
MAMM.E 383
HSRNIA 384
INGUINAL HERNIA 385
FEMORAL HERNIA 388
THE PERINJEUM 39*
PELVIC CAVITY AND FASCIA 391
MALE PERINEUM 393
ISCHIO-RECTAL REGION 394
FEMALE PERINEUM 395
LITHOTOMY 396
INDEX . 399
XIV
ABBREVIATIONS — EXPLANATION
ABBREVIATIONS
Anas. . .
Ant. . .
Art. or A.
Asc. . .
Br. . . .
Cerv. . .
Com. . .
Commun.
Desc. . .
Ext.
Anastomoses.
Inf. . . .
Inferior.
Anterior.
Int. . . .
Internal.
Artery.
L
Left.
Ascending.
M
Middle.
Branch.
N
Nerve.
Cervical.
PI
Plexus.
Common.
Post.. . .
Posterior.
Communicating.
R
Right.
Descending.
Sup. . . .
Superior.
External.
Superf . . .
Superficial.
Trans .
. Transverse.
EXPLANATION
Figures or letters in parentheses, .thus — (14), (a), refer to the same
figures or letters on the adjoining illustration; except in the Tables of
Arteries, in which figures in parentheses serve as cross-references to other
divisions of the tables.
A COMPEND OF
HUMAN ANATOMY
The term Anatomy is derived from the Greek a.va, through, and
T\nv€i,v, to cut, it strictly means dissection, but is technically applied to
that science which treats of the structure of organized bodies.
The divisions of Descriptive Human Anatomy are, — Osteology, the
anatomy of the bones; Syndesmology, of the joints; Myology, of the muscles;
Angiology, of the vessels; Neurology, of the nerves; Splanchnology, of the
internal viscera; Adenology, of the glands; Dermatology, of the skin;
Genesiology, of the generative organs.
OSTEOLOGY
The number of Bones in the Adult Human Skeleton is variously
stated by different anatomists. Excluding the teeth (which belong to
the tegumentary system), the Wormian and the sesamoid bones, the
number is 206. Excluding also the 6 ossicles of the middle ear the whole
number would be 200. Leaving out also the 2 patellae and the hyoid
bone, the number in the skeleton proper would be 197 bones. Of these,
the vertebral column contains 26, the cranium 8, the face 14, the walls of
the thorax (sternum and ribs) 25, the upper extremities 64, and the lower
extremities 60. They are divisible into four classes, — the long and short
medullated, and the flat and irregular cancellous bones.
Long Bones number 90, act as supports, or levers, and are known by
having a medullary canal. in the centre of each, a shaft (diaphysis), and
two extremities. They are developed by osseous deposit in cartilage, and
include the clavicle, humerus, radius, ulna, femur, tibia, fibula, meta-
carpal and metatarsal bones, and the phalanges.
Short Bones number 30, and are found where strength is required, but
limited motion. They are also developed by osseous deposit in cartilage
and include the bones of the carpus and tarsus, the former having 16 and
the latter 14.
2 HUMAN ANATOMY
Flat Bones number 38, protect the viscera by forming walls around them,
and afford extensive attachment for muscles. They are developed by
osseous deposit in membranes, and consist of 2 dense layers, separated by
a cellular or cancellous osseous tissue, the diploe. They include the oc-
cipital (os occipitale), parietal (os parietale), and frontal (os frontale)
'(bones of the cranium); the nasal (os nasale), lacrimal (os lacrimale),
and vomer (bones of the face); the scapula, os innominatum (os coxae),
sternum and ribs (costae).
Irregular Bones are 39 in number, and include the vertebrae, sacrum,
coccyx (coccygis), the temporal, ethmoid, and sphenoid bones, and
the bones of the face, except the nasal (os nasale), lacrimal (os lacrimale),
and vomer.
Bones of the Head number 22, and comprise the —
Cranial Bones 8, — the frontal, 2 parietal (ossa parietalia) , occipital (os
occipitale), 2 temporal (ossa temporalia), the sphenoid and the ethmoid
(os ethmoidale) .
Facial Bones 14, — 2 maxillary (maxillae), 2 malar (ossa zygomatica), 2
nasal (ossa nasalia), 2 lacrrmal (ossa lacrimalia), 2 palate (ossa
palatina), 2 inferior turbinal (conchae nasales inferiores), vomer and
mandible.
Bones of the Trunk number 53, as follows, viz. —
Vertebra 24, — 7 cervical, 12 thoracic, and 5 lumbar vertebrae.
Thorax 25, — 7 pairs of true ribs, 3 pairs of false ribs, 2 pairs of floating
ribs (articulating with the bodies of the thoracic vertebrae), and the
sternum.
Pelvis 4, — the sacrum, the coccyx (os coccygis), and 2 ossainnominata (ossa
coxae) each os innominatum consisting of 3, — the ilium (coxae),
ischium, and pubis.
Bones of each Upper Extremity number 32, as follows: —
Shoulder 2, — the clavicle (clavicula) and scapula.
Arm i, — the humerus.
Forearm 2, — the radius and ulna.
Hand 27, — 8 carpal bones, — the scaphoid (os naviculare), semilunar (os
triquetrum), cuneiform, pisiform (os pisiforme), trapezium (os mul-
tangulum majus), trapezoid (os multangulum minus), os magnum
(os capitatum), and unciform (os hamatum), — 5 metacarpal, and 14
phalanges.
Bones of each Lower Extremity number 29, viz. —
Thigh i, — the femur.
Leg 2, — the tibia and fibula.
OSTEOLOGY 3
Foot 26, — 7 tarsal bones, — the astragalus (talus), os calcis (calcaneus),
scaphoid, (naviculare pedis), cuboid (os cuboideum), external, (tertium)
middle (secundum), and internal cuneiform (primum), — 5 meta tarsal,
14 phalanges.
Unclassified Bones are the—
Patella 2, which are sesamoid bones, each developed in the tendon of the
quadriceps extensor femoris muscle.
Hyoid Bone (os hyoideum) i, — the tongue-bone not articulated to the
skeleton.
Malleus, Incus Stapes (3 pairs), — the bones of the middle ear (ossicula
auditis).
Sesamoid Bones, of variable number, situated in the tendons of the
gastrocnemius and peroneus longus muscles, and in the flexor tendons
of the great toe and the thumb.
Wormian Bones (ossa Suturarum), sometimes found in the cranial
sutures, are not constant in number or size.
Principal Eminences on Bones. Heads are convex and smooth, for
articulation in movable joints. Condyles are irregularly shaped heads.
Trochamers, when for turning the bone. Tuberosities are broad, uneven
prominences. Tubercles are small tuberosities. Spines, or Spinous proc-
esses, when sharp and slender. Apophysis (an excrescence), is a process
or marked bony prominence which has never been separate from the
bone. Epiphysis (an accretion), is a process which was developed sepa-
rately and afterward became united to the bone by ossification of the
intermediate tissue.
Other Names given to Bony Prominences. There are several adject
tives applied to them from their fancied resemblances, such as — Azygod,
without a fellow; Clinoid, like a bed; Coracoid, like a crow's beak; Coronoi,-
hooked like a cow's horn; Hamular, hook-like; Malleolar, like a mallet;
Mastoid, like a nipple; Odontoid, tooth-like; Pterygoid, wing-like; Rostrum,
a beak; Spinous, thorn-like; Styloid, pen-like; Squamous, scaly; Vaginal,
ensheathing, etc.
Cavities of Bones. Articular cavities are called Cotyloid, cup-like;
Ctenoid, shallow; Trochlear, pulley-like; Facet, if smooth; Alveolar or
Alveoli, when socket-like. Non-articular cavities are named fossae, sinu-
ses, aqueducts, foramina, canals, fissures, notches, cells, grooves, depres-
sions, etc.
Composition of Bone. Organic or animal matter, about ^, consisting
of gelatin, vessels and fat. Inorganic, or mineral, about %, consisting of
4 HUMAN ANATOMY
phosphate and carbonate of calcium (62^ per cent.), with fluoride of
calcium, phosphates of magnesium, sodium, and chloride of sodium (4^
per cent.). Heat will remove the organic matter and leave the inorganic;
dilute Nitric or Hydrochloric acid will remove the inorganic, and leave the
organic. In old age the inorganic constituents predominate, and the bones
are brittle; in youth the organic predominate, and epiphyseal dislocation
is more common than fracture, especially in the long bones of the
extremities.
Structure of Bone. Bone is composed of an outer compact layer, and
an inner cellular or spongy structure. It is surrounded, except at the articu-
lar cartilages, by a vascular fibrous membrane, the Periosteum, which
receives the insertions of all tendons, ligaments, etc.; and the central cavity
of long bones is lined by a similar structure, the Endosteum. The trans-
verse section of the bone, examined microscopically, shows —
Haversian Canals, — diameter /^oo inch, for the passage of vessels.
Canaliculi, — diameter Keooo inch, radiating from the canals, and con-
necting them with the lacunae.
Lacuna, — arranged circularly around the canals, and contain the
bone-cells, appearing as irregular dark spaces.
Haversian Spaces, — connect the canals with the medullary spaces, and
divide one Haversian system from another. An Haversian System
comprises an Haversian canal with its lamellae, lacunae, and canaliculi.
Concentric Lamella, — of bone tissue, around the canals.
Circumferential Lamella, — are bone layers binding the canals together.
~j Interstitial Lamella, — woven in between the concentric lamellae.
The Marrow of Bone. In young bones it is a tenacious, transparent
fluid, free from fat. In adult bones it is of a yellow color, and consists
of fat in varying proportion and extractive matters. It is found in the
medullary canal, the cancellous texture, and the large Haversian spaces.
Vessels found in Bones. Arteries, veins, and some say lymphatics.
The Arteries are, — the nutrient, entering at the nutrient foramen; the
articular, nourishing the cancellous structure; and the periosteal, which
supply the periosteum and the compact structure. The Veins emerge
from the ends, the shaft, and from the nutrient foramen.
The process of Ossification. The site of bone is first occupied by a
mucoid substance, which becomes temporary cartilage (blastema) in the
second month of foetal life. The young bone-cells (osteo-blasts) are
then deposited in the cartilage at certain points, and their deposition
and subsequent pressure cause the absorption of the cartilage. In most of
the bones of the head and face, ossification is intra-membranous instead
THE VERTEBRAL COLUMN 5
of intra-cartilaginous. The first bones in which ossification appears are
the clavicle and inferior maxillary (5th to 7th foetal week); the last is the
pisiform bone (i2th year). Epiphyses ossify after birth and begin uniting
to the bone from the age of puberty, and in the inverse order to that in
which their ossification began, except the lower end of the fibula, which
ossifies and is joined to the shaft earlier than its upper end.
, THE BONES OF THE TRUNK
A*-3V
THE VERTEBRAL COLUMN
Characteristics common to the Vertebrae. Each of the 24 spinal
vertebrae consists of a body and an arch, the latter being formed by 2
radix arcus vertebrae (pedicles) and 2 laminae, which support 7 processes.
The—
Body (corpus vertebrae) is thick and spongy, convex in front (i) from side
to side, concave vertically, and on the upper and lower surfaces, which
are surrounded by a bony rim. PIG. i.
Anteriorly are small foramina
for nutrient vessels, posteriorly
a large foramen for the exit of 5!
the venae basis vertebrarum.
Pedicles (radix arcus vertebrae) (7),
— project backward from the
body, inclining outwardly.
They are notched above and
below (incisura vertebralis su-
perior et inferior), thus form-
ing, with the adjacent notches,
the Inter vertebral Foramina
(Foramina Intervertebralia) for the entrance of vessels and the exit
of the spinal nerves.
Lamina, — are 2 broad plates, meeting in the spinous process behind,
and rough on their upper and lower borders for the attachment of
the ligamentum subflava.
Transverse Processes (4), — one on each side projecting outward; those
of the first ten thoracic vertebrae have articular facets (5) for the
tubercles of the ribs.
Articular Processes (Zygapophyses) (6), — two on each side, superior
(6) and inferior, project from the junction of the laminae and pedicles,
and articulate above and below with the articular processes of the
HUMAN ANATOMY
adjacent vertebrae. Their upper facets look backwards and upwards
in the cervical region, backwards and outwards in the thoracic, and
backwards and inwards in the lumbar.
Spinous Process (3), — projects backward from the junction of the laminae
with each other, sometimes very obliquely.
Spinal Foramen (foramen vertebrale) (2),— is the space enclosed by the
body, pedicles and laminae, and which, when the vertebrae are articu-
lated, forms part of the spinal or neural canal.
The Spinal Vertebrae are distinguished as cervical 7, thoracic 12,
and lumbar 5. Each of these divisions has several peculiar features, but
their especial characteristics are as follows: —
Cervical Vertebra, — are pierced at the bases of their transverse processes
by the costo-transverse foramina, which transmit the vertebral artery,
vein, and plexus. The anterior boundary of a costo-transverse
foramen is called the Costal process, it is a true cervical rib. Its
termination is called anterior tubercle of the transverse process. The
posterior tubercle is the tip of the true transverse process. The
superior articular facets look backwards and upwards.
Thoracic Vertebrae, — have facets and demifacets on their bodies, for
articulation with the heads of the ribs, these facets are called the
foveae costales. The superior articular facets look backwards and
outwards.
Lumbar Vertebra, — are marked by the absence of the foramina and facets
which distinguish the other two classes. The superior articular facets
look backwards and inwards.
Peculiar Vertebrae are 9 in number, — the Atlas or ist cervical, the Axis
or 2d cervical (epistropheus), the Vertebra Prominens, or 7th cervical
(the ist thoracic is nearly always
more prominent), the ist, Qth,
icth, nth, and i2th thoracic,
and the 5th lumbar. The —
^Jlas (3), — is a bony ring sup-
porting the head. A bony
arch takes the place of a
body, and its spinous process
is a mere tubercle. Its Lat-
eral Masses (i) form its
chief bulk, supporting large Articular Processes (foveae articulares),
which look inwards, the superior (2) articulating with the condyles
of the occipital bone.
FIG. 2.
THE THORAX 7
Axis (9), — is marked by its Odontoid Process (dens) (10) projecting up-
ward from the body into the anterior part of the spinal foramen of
the atlas, where it articulates with the anterior arch (3), and receives
the occipito-axoid (ligamentum apicis dentis) and the check liga-
ments (ligamenta alaria). Its transverse processes (8) are very small
and are not bifid. Its inferior articular surfaces (7) have the same
direction as those of the other cervical vertebrae.
Vertebra Prominens, — has a long and prominent spinous process which
ends in a tubercle for the ligamentum nuchae.
Thoracic Vertebra. The ist has one facet and a demifacet for the ist
and 2d ribs. The gth has a demifacet only. The loth has but one
facet on the body and one on the transverse process. The nth and
1 2th have each but one facet on the body, and none on the transverse
processes. The i2th resembles a lumbar vertebra in size and shape.
5th Lumbar Vertebra, — is much deeper in front than behind; its spinous
process is small, but its transverse processes are large and thick, and
point slightly upward.
Important Relations of Certain Vertebrae.
3<f Cervical corresponds in situation to — the bifurcation of the common
carotid artery, and the superior cervical ganglion.
5fh Cervical, to — the junctions of the larynx with the trachea and the
pharynx with the oesophagus, and the middle cervical ganglion of the
sympathetic.
id Lumbar, to — the junction of the duodenum with the jejunum, the com-
mencement of the thoracic duct and the portal vein, the origin of the
superior mesenteric artery, the lower margin of the pancreas, the opening
of the ductus communis choledochus, the lower end of the spinal cord,
and the crura of the diaphragm.
[The sacral and coccygeal vertebrae are described as bones of the pelvis.]
THE THORAX
The Thorax is an osseo-cartilaginous cage formed by the bodies of the
dorsal vertebrae posteriorly, the ribs and costal cartilages laterally, and
the sternum in front. Its shape is conical, the axis inclined forward, the
base below and closed by the diaphragm.
Structures passing through its Apex, are — the trachea, oesophagus,
large vessels of the neck, pneumogastric (vagus), phrenic, and sympathetic
nerves, thoracic duct, and in inspiration the apex of the lung.
8
HUMAN ANATOMY
FIG. 3.
Structures contained in its Cavity, are — the trachea, bronchi and
lungs, the heart and great vessels, internal mammary arteries, azygos and
bronchial veins, pneumogastric, phrenic, and splanchnic nerves, oesopha-
gus, thoracic duct, lymphatic vessels and glands.
The Sternum, or breast-bone, consists of 3 parts — the manubrium (i),
or handle; the gladiolus (2), or sword; and the ensiform or xiphoid appen-
dix (3). It presents the —
Inter clavicular Notch, — on its superior border.
Manubrium (i), — articulates
with the clavicle, ist costal
cartilage, and a part of
the 2d.
Gladiolus (2), — articulates
with the costal cartilages
from the 3d to the 6th in-
clusive, and partly with
the 2d and 7th.
Ensiform Appendix (3), — ar-
ticulates with the cartilage
of the false ribs, and in
part with the 7th costal
cartilage. It is cartilag-
inous in youth.
Development and Muscles.
The sternum is developed- by 6
centres, i each for the manu-
brium and ensiform appendix
and 4 for the gladiolus. The
muscles attached to it are 9 pairs and one single muscle, — the sterno-
cleido-mastoid, sterno-hyoid and sterno-thyroid, 3, to its upper part; —
the rectus abdominis, external and internal oblique, transversalis and the
diaphragm, 5, to its lower part; — the pectoralis major, i, anteriorly; —
and the triangularis sterni, i, posteriorly.
The Ribs are 12 in number on each side, 7 of which are true ribs, being
each connected to the sternum by a separate cartilage; — and 5 are false
ribs. Three of the latter are connected by their cartilages to the cartilage
of the 7th rib (n), while two are called floating ribs (10), having each one
extremity free.
Characteristics Common to most of the Ribs. Each rib consists of
a head, neck and shaft, and presents the following points, viz. —
THE PELVIS 9
Head, — is divided by a ridge into 2 facets, which articulate with the
facets on the bodies of the dorsal vertebrae, the lowermost facet is
always slightly the larger; the ridge giving attachment to the inter-
articular ligament.
Neck about an inch long, presents on its upper border a crest which
affords attachment to the ligamentum costo-transversarium anterius
(superior costo-transverse), to its posterior surface the middle costo-
transverse ligament (1. colli costae), its anterior surface is smooth.
Tuber osity, — at the junction of the neck with the shaft, has a facet for
articulation with the transverse process of the next lower vertebra,
and a rough surface for the posterior costo-transverse ligament
(1. tuberculi costae).
Shaft, — twisted on itself, is concave internally, convex externally, its
upper border round and smooth, its lower border grooved for the
intercostal vessels and nerves. At its external extremity is an oval
depression for the insertion of the costal cartilage.
Angle, — just in front of the tuberosity, is marked by a rough line, to
which are attached the muscles of the deep layer of the back.
Development. Each rib has 3 centres, one each for the head, shaft,
ind tuberosity. The last 2 ribs, having no tuberosity, are developed
each by 2 centres.
Peculiar Ribs, are the ist, 2d, loth, nth, and i2th. They respectively
present the following peculiarities —
ist Rib, — is broad, short, not twisted, has no angle, only one facet on
the head; but on its upper surface are seen two grooves for the subclavian
artery and vein, and between them a tubercle for the scalenus anticus
muscle.
2d Rib, — is not twisted, its tuberosity and angle are very close together,
and its upper surface presents rough surfaces for the serratus magnus
and scalenus posticus muscles.
loth Rib, — has but one facet on its head.
nth Rib, — has no neck, no tuberosity, and but one facet on its head.
i2th Rib, — has neither neck, angle, tuberosity nor groove, and but one
facet on its head.
THE PELVIS
The Pelvis is formed by the sacrum, os coccygis (coccyx), and two ossa
innominata (coxae) and is divided into, — the pelvis major (false pelvis),
comprising the upper and expanded portion, — and the pelvis minor
(true pelvis), below the ilio-pectineal line (linea arcuata). The false
10
HUMAN ANATOMY
FIG. 4.
pelvis corresponds to the iliac fossae (i), and is marked by its walls being
deficient anteriorly between the iliac borders, and posteriorly between the
sacrum and the posterior iliac spines. The true pelvis has a —
Brim, or inlet (apertura pel vis minor superior), — bounded in front by
the crest and spine of the pubes (7), behind by the promontory of
the sacrum (15), laterally by the ilio-pectineal line (linea arcuata).
Its axis corresponds to a line intersecting the umbilicus and the middle
of the coccyx (os coccygis). Its average diameters in the female
are, — 4 inches antero-posteriorly, over 5 inches transversely, under 5
inches obliquely. In the
male each of these meas-
urements is about % an
inch less.
Cavity, — is a short curved
canal, connecting the
brim with the outlet.
In front its depth is about
i% inches, posteriorly 4
to 4^ inches in the
female, 4^ to 5^ inches
in the male. Its diameter
is about 4% inches in the
female, 4>£ inches in the
male, all around.
Outlet (apertura pelvis minor inferior), — is bounded by the pubic arch
above (n), the tip of the coccyx (os coccygis) behind, and the
tuberosities of the ischia (9) laterally. Its axis, if prolonged, would
touch the promontory of the sacrum. Its diameters in the female are
each about 4^ inches, in the male about 3^ inches.
Chief Differences between the male and female pelves. The male
pelvis is marked by strength of the bones, prominence of the muscular
impressions, a deep and narrow cavity, and large obturator foramina.
The female pelvis has lighter bones, broader iliac fossae, the spines being
further apart, greater diameters at every point, the sacrum less curved,
and the pubic arch wider.
The Sacrum, or sacred bone, is triangular, curved, with its convexity
backward, and is situated, base upwards, between the ossa innominata
(coxae) forming with the coccyx the posterior wall of the pelvis. The bone
consists of a central portion (4) which consists of the coalesced bodies
of five vertebrae, and on each side a pars lateralis (lateral mass) or ala (wing)
THE PELVIS
II
FIG. 5.
which is made by the fusion of the transverse processes and what might
be called "pelvic ribs." Therefore the pars lateralis presents a trans-
verse portion and a costal or alar portion. The sacrum presents the
following points, viz. —
Ridges (cristae sacral es articulares) (4), — four transversely across both
surfaces, mark the union of its original seg-
ments.
Anterior Sacral Foramina, — eight for the an-
terior sacral nerves.
Grooves (5), — eight shallow and broad, for the
aforesaid nerves.
Promontory, — at its junction with the last lum-
bar vertebrae.
Posterior Sacral Foramina, — eight for the pos-
terior sacral nerves.
Tubercles, — representing the spinous processes
of the segments.
Groove, — posteriorly, on each side of the spinous tubercles.
Cornua, — two at the posterior inferior portion of the bone.
Articular Surface (3), — on each side, articulates with the ilium.
Notch, — laterally and inferiorly, for the 5th sacral nerve.
Base (2), — has all the characteristics of the lumbar vertebrae, with the
last of which it articulates.
Apex (16), — has an oval surface for articulation with the coccyx.
Sacral Canal, — the continuation of the spinal canal, is incomplete pos-
teriorly at its lower end. It transmits the Cauda Equina; into it
open the sacral foramina laterally.
The Coccyx consists of 4 (or 5) rudimentary caudal vertebrae coalesced
FlG 6 into a triangular bone, the base (i) of which articu-
lates with the apex of the sacrum. Its posterior sur-
face is rough for muscles and ligaments, its anterior
surface is smooth and marked by ridges at the junction
of its constituent vertebrae. It presents the following
points: —
Cornua (2), — two superiorly,, articulating with the
sacral cornua to form foramina for the 5th sacral nerves.
Apex, — is sometimes bifid and turned to one side.
The Ossa Innominate (coxae), are placed one on each side of the
osseous pelvis, and are each formed by the union, about puberty,
12 HUMAN ANATOMY
of 3 bones, — the ilium, ischium, and pubes. The innominate (os coxae)
as a whole presents the following points, viz. —
It is a large flat bone, constricted in the middle, and twisted upon its
long axis, so that the expanded portion (iliac) above the constriction is in
a plane almost at right angles to that of the expanded portion (ischio-
pubic) below. It presents an outer surface, an inner surface, and a con-
tinuous border which is circumferential. Beginning at its upper part the
border of the os coxae (innominate or hip bone), it presents a crest (i),
and, continuing forwards and around, the anterior superior spine (2),
a shallow notch, the anterior inferior spine (4), a smaller notch, the ilio-
pectineal eminence (5), superior (ascending) ramus or body of the ossis
pubis, pubic tubercle (spine) and crest of pubis (9), the symphysis ossis
pubis, the ischio-pubic ramus (9), constituted in front by the inferior (hori-
zontal or descending) ramus of the pubis and behind by the ramus of the
ischium, the tuber ischiadicum (tuberosity of the ischium) 12, the lesser
sciatic (sacro-sciatic) notch (13), the ischial spine 14, the greater sciatic
(sacro-iliac) notch (16), the posterior inferior spine of the ilium (17), and
lastly the posterior superior spine of the ilium. The inner surface is divided
by the ilio-pectineal line into an upper portion and a lower portion. The
upper portion (false pelvis) presents in front the iliac fossa, and behind, the
articular (auricular) surface and a rough surface for the posterior sacro-
iliac ligament. The lower part of the inner surface (true pelvis) presents
the obturator groove and the obturator foramen (8). In addition to
what is described with the ilium, ischium and pubes, the outer surface
presents : —
Acetabulum, or cotyloid cavity, — receives the head of the femur. It is
situated at the junction of the 3 bones externally, the ilium and
ischium each forming about two-fifths, and the pubic bone one-fifth
of it. A depression in its centre lodges a mass of fat containing
vessels for the nourishment of the synovial membrane. The Cotyloid
Notch (Incisura Acetabuli) is a deficiency in its lower margin, trans-
mitting nutrient vessels to the joint; to the edges of the notch is
attached the ligamentum teres, and it is bridged over by the trans-
verse ligament, a continuation of the cotyloid ligament (labrum
glenoidale) which surmounts the brim of the acetabulum. Crossing
the ischium horizontally, immediately below the acetabulum, is a
deep groove for the obturator externus tendon.
Obturator or Thyroid Foramen (8), — on the anterior surface between the
pubes and ischium, large and oval in the male, small and triangular
in the female; is closed by the obturator membrane, except above
THE PELVIS 13
at the obturator canal or groove where the obturator nerves and
vessels pass through.
The Ilium is the superior part of the innominate bone, its outer surface
presents the following points, viz. —
Crest (i), — along its upper border, having an outer and inner lip for
muscular attachment, and ending in the superior spines.
Anterior Superior Spine (2), — to which are attached the sartorius and
tensor fasciae (vaginae) femoris muscles and the inguinal (Poupart's)
ligament.
Anterior Inferior Spine (4), — for the straight tendon of the rectus femoris.
Notch, between the above-named spines,
transmitting the external (lateral) cu-
taneous nerve, and lodging some fibres
of the sartorius.
Posterior Superior Spine (19), — for the at-
tachment of the erector spinae muscle,
and the oblique part of the sacro-iliac
ligament.
Posterior Inferior Spine (17), — for the sacro-
tuberous (great sacro-scia tic) ligament.
Great Sciatic (Sacro-iliac) Notch (16), —
below the last-named spine, transmits
the great sciatic, superior gluteal, and
pudic (pudendal) nerves, the pyriformis
muscle, and the sciatic, pudic (pudendal) and gluteal vessels, also a
nerve supplying the obturator externus muscle.
Gluteal ridges (Curved Lines) (21) posterior, anterior, and inferior, on
the outer surface of the bone, from the spaces between which arise
the glutei muscles.
Groove, — above the acetabulum, for the reflected tendon of the rectus
femoris muscle.
The Ischium is the lowermost portion of the os coxae (innominate bone),
and presents the following points, viz. —
B ody (superior ramus), — forms two-fifths of the acetabulum, and the
external margin of the obturator foramen; on it is a broad groove for
the tendon of the obturator externus muscle. Its posterior margin
assists in forming the great sciatic (sacro-sciatic) notch.
Spine (14), — for the gemellus superior, coccygeus, and levator ani
muscles, and the lesser sacro-sciatic ligament.
Lesser Sciatic (Sacro-sciatic} Notch (13) — below the spine, transmits the
14 HUMAN ANATOMY
obturator muscle, its nerve, and the pudic vessels and nerve as
they re-enter the pelvis, having crossed the spine of the ischium.
The sacro-sciatic notches are converted into foramina by the sacro-
sciatic ligaments; the greater notch by the lesser ligament (sacro-
spinous), the lesser notch by the greater ligament (sacro-tuberous).
Tuberosity (12), — the lowest and most prominent part, gives attach-
ment to the greater sacro-sciatic (sacro-tuberous) ligament, and to
several muscles. On it one rests when sitting.
Horizontal Ramus (inferior ramus), — bounds the obturator foramen
inferiorly, articulates with the (descending) (inferior) ramus of the
pubes, and gives attachment to the obturator membrane and several
muscles.
The Pubes. The pubic or pectineal bone forms the anterior portion
of the innominate. It presents the following points, viz. —
Body, — with its fellow forms the Symphysis, giving origin to several
muscles and ligaments.
Crest (9), — on the upper part of the body, terminates externally in the
spine.
Spine, — affords attachment to one end of inguinal (Poupart's) ligament.
(Linea Ilio-pectinea), (pecten ossis pubis) in part, — gives attachment to
the conjoined tendon, Gimbernat's (lacunar) ligament, and the tri-
angular ligament.
Horizontal Ramus, — forms part of the margin of the obturator fora-
men, and of the acetabulum.
Pectineal Eminence (5), — gives attachment to the psoas parvus muscle.
Muscles attached to the hip bone number 36, comprising those of
the abdomen, thigh, perineum, floor of the pelvis, and rotators of the
hip-joint.
THE BONES OF THE HEAD
THE FRONTAL BONES (OS FRONTALE), (i, Fig. 8)
Points on its Frontal (Vertical) Portion, are as follows: —
Externally, — An upper angle (6), — Lateral angles (12), — •
Frontal Eminences (tuberosities) , — one on each side of the median line.
Depression, — marking the site of the frontal (metopic) suture before
obliteration.
Superciliary Arches (Ridges), — behind which are the frontal sinuses.
Supraorbital Notches or Foramina, — in the supraorbital arches, at about
their inner third, for the supraorbital vessels and nerves.
Nasal Eminence (24), — at lower end of the frontal depression.
THE FRONTAL BONE 15
External Angular, (Lateral or Zygomatic) Processes (13), — articulate
with the malar (zygomatic) bones and form the anterior part
of the temporal ridges.
Internal (Medial) Angular Processes, — articulate with the lacrimal
bones.
Nasal (Frontal) Spine and Notch, — between the internal angular
processes.
Internally, —
Sagittal Sulcus or Groove, — for superior longitudinal sinus and the
falx cerebri.
Frontal Crest, — for attachment of the falx cerebri.
Foramen Coecum, — for a small vein to the longitudinal sinus.
FIG. 8.
Depressions and Elevations, — for convolutions of the brain.
Between the two tables of the vertical portion in the adult are the —
Frontal Sinuses, — two spaces at the anterior inferior part of the bone,
which are lined with mucous membrane, and open into the middle
meatus of the nose.
The Orbital Plates (Pars Orbitalis). Each plate presents the following
points, —
Fossa, — for the lacrimal gland, near the external angular process.
Fovea Trochlearis, — a depression at the nasal margin for the pulley of
the superior oblique muscle.
1 6 HUMAN ANATOMY
Ethmoidal Notch, — having the following foramina on its margin.
Anterior Ethmoidal Foramen, — for the anterior ethmoidal vessels and
the naso-ciliary branch of the ophthalmic nerve.
Posterior Ethmoidal Foramen, — for posterior ethmoidal vessels.
Grooves, — on the cranial surface, for branches of the anterior and middle
meningeal arteries.
Articulations, Development, and Muscles. Each half of the frontal
bone articulates from its upper angle to its lateral angle, with the parietal, —
from lateral angle to zygomatic process, with the front part of the apex of
the Great Wing of the sphenoid, — zygomatic process, with the malar, —
posterior border of orbital plate, with Lesser Wing of the sphenoid, mar-
gins of ethmoidal notch with the ethmoid, — medial border of the orbital
plate from behind forwards, with orbital plate of ethmoid, — lacrimal,
nasal process of maxilla, — frontal spine, with the nasal. It is developed by 2
centres in membrane, i for each lateral half. The muscles attached to
it are 3 pairs, — the temporal, corrugator supercilii, and orbicularis palpe-
brarum.
THE PARIETAL BONES, (2, Fig. 8)
General Characteristics. They are 2 quadrilateral bones situated
at the superior and lateral regions of the cranium. Each has a frontal
(anterior superior) angle (6), anterior border, sphenoidal (anterior
inferior) angle (10), a lower border, a truncated mastoid (posterior
inferior) angle (9), a posterior border, an occipital (posterior superior)
angle (7), and an upper border. The articulations are, — the superior
border of each joins the other by the Sagittal Suture; the anterior border
joins the frontal bone forming the Coronal Suture (6) ; the posterior border
articulates with the occipital, forming the Lambdoid Suture (7); the inferior
border from before backwards with the great wing of the sphenoid (5),
squamous and mastoid portions of the temporal (4). Forming the lateral
walls of the skull they are named parietal, from paries, a wall.
Points on each Parietal Bone. Externally the bone is convex and pre-
sents for examination, —
Temporal Ridge (13), — continuous with the same on the frontal bone,
bounded above by the superior temporal line, and below by the in-
ferior temporal line.
Parietal Eminence (tuberosity) , — the point where ossification com-
menced.
Parietal Foramen, — close to the upper border, transmits an emissary
THE OCCIPITAL BONE IJ
vein to the superior longitudinal (sagittal) sinus. Is not constant.
Internally, the bone is concave, and marked by — •
Depressions, — for the Arachnoideal Granulations (Pacchionian bodies),
and for the cerebral convolutions.
Furrows, — for branches of the middle meningeal artery.
Groove, — for the lateral (transverse) sinus, at the posterior inferior
angle.
Half-groove, — along the upper border, for the superior longitudinal
(sagittal) sinus of the dura mater.
Development. Each parietal bone is developed from i centre in mem-
brane. The only muscle attached to it is the temporal.
FIG. 9.
THE OS OCCIPITALE, (3, Fig. 8)
is a symmetrical bone. Its border presents an upper angle, and on each
side, lateral angle, jugular process, jugular notch, petrosal process
along the edge of the basilar proc-
ess, and the apex of the basilar
process.
General Features and Surfaces.
It is trapezoidal in form, curved
upon itself, and placed at the pos-
terior and inferior region of the
cranium. Externally its surface
is convex and presents for exami-
nation the following, viz. —
External Occipital Protuberance
(5), and Crest (4), for the at-
tachment of the ligamentum
nuchae.
Superior and Inferior Nuchal
(Curved} Lines, — extending
outward on each side of the
external occipital crest; in one skull in every six there is to be seen
a supreme nuchal line above the others.
Foramen Magnum (2), — transmitting the medulla oblongata and its
membranes, the vertebral arteries, and the recurrent portions of the
spinal accessory nerves.
Condyles (6), — two in number, for articulation with the atlas.
Tubercles, — i on each condyle, for the check ligaments.
l8 HUMAN ANATOMY
Anterior Condylar Foramina (canalis hypoglossi),— two for the
hypoglossal nerves.
Posterior Condylar Foramina (canalis condyloideus posterior) (3), —
two (often absent) for emissary veins.
Jugular Processes (7), — two, each partly bounding the foramen lacerum
posterius basis cranii.
Jugular Fossa (8), — each forming part of the foramen lacerum posterius
basis cranii.
Internally, the surface is concave, showing —
Fosses, — four for the cerebellar and posterior cerebral lobes.
Internal Occipital Protuberance, — where 6 cranial sinuses meet to form
the torcular (wine-press) Herophili.
Crucial Ridge, — the vertical portion for the falx cerebri and falx cerebelli;
the transverse portion for the tentorium cerebelli, having also a groove
for the lateral (transverse) sinus.
Groove, — for the lateral (transverse) sinus, and the inferior petrosal
sinus, along the postero-lateral border.
Internal Openings, — of the foramina described above.
Basilar Process (i) of the Occipital lies in front of the foramen mag-
num (2), articulates with the body of the sphenoid bone, smooth and
grooved in the mid-line for the medulla oblongata and pons varolii, which
lie upon it, grooved laterally by the inferior petrosal sinuses; rough in-
feriorly for the attachment of muscles, and presenting the —
Pharyngeal Tubercle or Spine, — for the attachment of the superior con-
strictor muscle of the pharynx and its tendinous raphe.
Articulations and Development. The occipital articulates as follows. —
The condyles articulate with atlas, apex of the basilar process with body
of sphenoid, side of basilar process and apex of jugular process with
petrous portion of temporal, from jugular to lateral angle with mastoid
portion of temporal, from lateral angle to upper angle with parietal. It
is developed by 4 centres, i each for the posterior part, the basilar process,
and the 2 condyles; its ossification being completed about the 6th year
of age.
Muscles attached to the Occipital Bone. There are 12 muscles at-
tached on each side to the following portions, viz. —
Superior Nuchal Line 3, — the occipito-frontalis, trapezius, and sterno-
cleido-mastoid muscles.
Space between the nuchal lines 2, — the complexus and splenius.
Space below the inferior nuchal line 3, — the obliquus capitis superior,
rectus capitis posticus major and rectus capitis posticus minor.
THE TEMPORAL BONE
Basilar Process 3, — the superior constrictor of the pharynx, rectus capitis
anticus major and rectus capitis anticus minor.
Jugular Process i, — the rectus capitis lateralis.
FIG. 10.
THE TEMPORAL BONES (OSSA TEMPORALIA), (4, Fig. 8)
Situation and Divisions. They are situated at the inferior lateral
portions of the skull, and contain the organs of hearing. Each bone is
formed by the union of three parts, namely, the Squamous, Petro-mastoid,
and Tympanic.
The Squamous Portion is a semicircular plate, smooth externally, and
grooved internally for the middle
meningeal artery, with depres-
sions for the cerebral convolu-
tions. Externally are seen the —
Zygomatic Process (d\ or
Zygoma, — arising by 3 roots,
and extending forward to
articulate with the malar
bone.
Zygomatic Tubercle (e), at the
base of the process, for the
external lateral ligament of
the lower jaw.
Anterior Articular Ridge (emi-
nentia articularis), — formed
by the anterior root of the zygoma.
Mandibular (Glenoid) Fossa (g), — between the anterior and posterior
articular ridge (middle root of the zygoma) for articulation with
the condyle of the lower jaw, and is covered with cartilage.
Glaserian Fissure, — divides the squamous from the tympanic; it trans-
mits the laxator tympani muscle, the tympanic artery, and lodges
the processus gracilis of the malleus and the inferior process of the
petrous.
Opening of the Canal of Hugier, — lies in the angle between the squamous
and petrous portions of the bone; and transmits the chorda tympani
nerve.
Temporal Ridge (/), — in part, here known as the suprameatal ridge.
THE PETRO-MASTOID, — is usually described as consisting of a mastoid
portion and a petrous portion.
20
HUMAN ANATOMY
FIG. ii.
The Mastoid Portion. Its cerebellar surface is grooved for the lateral
sinus (9); externally it presents the following, —
Mastoid Foramen (h)y — the largest of several foramina, for a vein.
Mastoid Process, — at the tip, for the sterno-cleido-mastoid, splenius, and
trachelo-mastoid muscles.
Digastric Fossa (j}, — for the posterior belly of the digastric muscle.
Occipital Groove (8), — for the occipital artery.
The Mastoid Cells, — in the interior of the mastoid process, open on the
posterior wall of the middle ear, and are lined with mucous membrane.
The Petrous Portion is very hard, pyramidal in form, contains the in-
ternal ear, projects inward and forward, and presents a base, an apex, a
cerebral surface, cerebellar surface, tympanic surface, and basilar surface;
upper border, anterior border, pos-
terior border; the tympanic bone is
blended with the inferior border and
conceals it.
On the Base are seen, the —
Meatus Auditor ius Externus (i), —
the external opening of the ear.
Auditory Process of the Tympanic, —
a bony ring for the external car-
tilage of the ear.
Apex lies internally, at the base of
the skull, forming the outer
boundary of the foramen lacerum
medium, and contains the internal
carotid canal.
CEREBRAL (Anterior) Surface, presents from within outward —
Inner Opening of the Carotid Canal (n), — for the internal carotid artery
and plexus.
Depression, — for the Gasserian ganglion of the 5th pair of cranial nerves.
Hiatus Canalis Facialis or Hiatus Fallopii, — for the great petrosal nerve,
branch of the middle meningeal artery.
Foramen, — for the small petrosal nerve.
Eminence, — over the superior semicircular canal of the ear.
Depression, — over the tympanum.
Cerebellar (Posterior) Surface presents, —
Meatus Auditorius Internus (12), — transmits the yth and 8th pairs of
cranial nerves and the auditory artery, and lodges a process of dura
THE TEMPORAL BONE 21
Opening of the Aqu&ductus Vestibuli (13), — transmits to the vestibule a
small artery and vein, and lodges a process of dura mater.
Basilar (Inferior) surface, presents from within outward —
Rough Quadrilateral Surface (19), — for the origin of the tensor tympani
and levator palati muscles.
Opening of the Carotid Canal, — transmitting the internal carotid artery,
and the carotid plexus of the sympathetic nerve.
Aqu&ductus Cochlea, — transmitting an artery and vein to the cochlea.
Jugular Fossa, — a depression for the sinus of the internal jugular vein,
forming with the occipital bone the foramen lacerum posterius, which
transmits that vein and the 8th pair of cranial nerves, etc.
Foramen for Jacobson's Nerve (tympanic branch of the glossopharyn-
geal), — in the ridge between the jugular fossa and the carotid canal.
Foramen for Arnold's Nerve (auricular branch of the pneumogastric), —
in the outer wall of the jugular fossa.
Jugular Surface, — for articulation with the jugular process of the occi-
pital bone. The Tympanic Surface can be seen by looking in the
external auditory canal, forms most of the osseous wall of the middle
ear or tympanum. It presents the Promontory of the Cochlea,
Fenestra Vestibuli, and Fenestra Cochlea.
The Tympanic Bone forms most of the external auditory canal. Its
under surface is slightly concave, forming a fossa for part of the parotid
gland. It presents a sharp ridge which projects downwards, and forms
the,—
Vaginal Process (1), — ensheathing the root of the styloid process.
Styloid Process (14), — a long projection for the stylo-pharyngeus, stylo-
hyoid, and stylo-glossus muscles; and the stylo-hyoid and stylo-
mandibular ligaments, which are attached thereto.
Stylo-mastoid Foramen (15), — between the styloid and mastoid processes,
for the exit of the facial nerve, and the entrance of the stylo-mastoid
artery.
Auricular Fissure, — for the exit of the auricular branch of the vagus
(Arnold's nerve).
In the angle between the petrous and squamous portions, are seen the —
Septum Tuba, — a lamina separating the following canals. Its inner end
projects into the tympanum, and is called iheProcessus cochleariformis.
Opening, — of the canal for the tensor tympani muscle.
Osseous Opening, — of the Eustachian tube (n) inferiorly.
The Anterior Border articulates partly with the alar spine of the
sphenoid bone.
22 HUMAN ANATOMY
The Posterior Border assists in forming the jugular foramen, and is grooved
for the inferior petrosal sinus.
The Superior Border separates the anterior fossa of the skull from the
middle fossa; to it is attached the tentorium cerebelli, and it is grooved
for the superior petrosal sinus (10), and in infants it presents afloccular
fossa.
Articulations and Development. The temporal articulates as follows, —
Anterior border of the petrous and squamous with the great wing of the
sphenoid, — upper border of the squamous and mastoid with the parietal, —
posterior border of the petro-mastoid with the occipital, — apex of zygo-
matic process with malar, and indirectly the glenoid fossa with the
mandible. It is developed by 4 principal centres, one each for the squamous
portion, styloid process, and tympanic, and one for the petro-mastoid
portions. Its ossification is completed about the 2d or 3d year.
Muscles attached to it. There are 14 muscles attached to the following-
named portions. To the —
Squamous Portion 2, — the temporal and masseter.
Mastoid Portion 6, — the occipito-frontalis, sterno-cleido-mastoid, splen-
ius capitis, trachelo-mastoid, digastric, and retrahens aurem.
Petrous Portion 3, — the tensor tympani, levator veli palatini (leva tor
palati) and stapedius.
Styloid Process 3, — the stylo-glossus, stylo-hyoid, and stylo-pharyngeus.
THE SPHENOID BONE, (5, Fig. 8)
Position and Form. Wedged in between the bones of the skull ante-
riorly, it resembles a bat with out-stretched wings. It is named from the
Greek word <r^v, a wedge, enters into the formation of 5 cavities, 4 fossae,
3 fissures, and presents for description —
Body of the Sphenoid Bone. Placed in the median line, cuboid in shape,
it presents on its UPPER SURFACE from before backward, the following
points, —
Sphenoidal or Ethmoidal Spine (3), — articulating with the ethmoid bone.
Smooth Surface, — grooved for the olfactory nerves.
Sulcus Chiasmatis or Optic Groove, — supporting the commissure of the
optic nerves.
Tuberculum Settee or Olivary Process, — an olive-shaped eminence behind
the optic groove.
Middle Clinoid Processes, — bounding the Sella Turcica in front.
Fossa Hypophyseos or Sella Turcica (16) (Turkish saddle), lodges the
hypophysis (pituitary body) and the circular sinus of the brain.
THE SPHENOID BONE 23
Dorsum Sella (cantle of the saddle) (16), — grooved for the 6th nerves.
Posterior Clinoid Processes (6), — for attachment of the tentorium cere-
belli, grooved by the optic tracts.
FIG. 12.
Grooves, — laterally, for the cavernous sinus and internal carotid artery.
POSTERIOR SURFACE is rough and quadrilateral (15) : it articulates with the
basilar process of the occipital bone, ossification being completed from
the 1 8th to the 2oth year of age.
FIG. 13.
ANTERIOR SURFACE is nearly vertical, and presents the —
Sphenoidal crest, — in the median line, articulating with the perpendicu-
lar plate of the ethmoid bone, and forming part of the nasal septum-
Openings of the Sphenoidal Sinuses (e), — cavities in the body of the bone
which exist in adults, not in children.
24 HUMAN ANATOMY
Sphenoidal Concha or Sphenoidal Turbinal Bones, — which partially close
the sinuses, and articulate with the ethmoid and orbital processes of
the palate bones.
INFERIOR SURFACE helps to form the nasal fossae, and presents the —
Rostrum (d), — which articulates with a groove on the vomer.
Alar Grooves, — on each side of the rostrum, for articulation with the
wings of the vomer.
Vaginal Processes, — i on each side of the rostrum.
Pterygo-palatine Grooves, — which, with the sphenoidal processes of the
palate bones, form the pterygo-palatine canals, for the transmission
of the pterygo-palatine arteries and nerves.
Greater Wings of the Sphenoid. Each wing presents on its CEREBRAL
SURFACE the following points, —
Foramen Rotundum (8), — for the maxillary division of the 5th nerve.
Foramen Ovale (9), — for the mandibular division of the 5th nerve, the
small petrosal nerve, and small meningeal artery.
Foramen Vesalii, — transmitting a small vein; often absent.
Foramen Spinosum (10), — transmitting the middle meningeal artery
and veins, also sympathetic filaments from the cavernous plexus.
THE ORBITAL or ANTERIOR SURFACE assists in forming the external wall of
the orbit, the inferior orbital (spheno- maxillary) and superior orbital
(sphenoidal) fissures. It articulates with the frontal and malar
bones, and presents a —
Notch, — transmitting a branch of the ophthalmic artery.
Spine, — for part of the lower head of the external rectus muscle.
External Orbital Foramina, — transmitting nutrient arterial branches.
EXTERNAL SURFACE consists of an upper portion, the temporal, separated
by a ridge, the infra-temporal crest, from a lower portion, the spheno-
maxillary surface. It presents the following points, —
Infra-temporal or Pterygoid Ridge, — dividing the temporal fossa from
the spheno-maxillary.
Alar Spine of the Sphenoid (n),— to which are attached the internal
lateral ligament of the lower jaw, and the laxator tympani muscle.
CIRCUMFERENCE is partly serrated for articulation with the temporal and
frcntal bones, and partly smooth for the anterior margin of the foramen
lacerum medium and the inferior margin of the superior orbital (sphe-
noidal) fissure, which margins it assists in forming.
Lesser Wings (i) of the Sphenoid, or the Processes of Ingrassias (a), —
terminate internally in the Anterior Clinoid Processes (5); their anterior
borders articulate with the orbital plate of the frontal bone, the posterior
THE SPHENOID BONE 25
are free, dividing the anterior cerebral fossa from the middle ones. Con-
nected intimately with each of these wings are the —
Optic Foramen (4) , — formed by the separation of its roots, and transmit-
ting the optic nerve and the ophthalmic artery.
Superior Orbital or Sphenoidal Fissure (7), or Foramen Lacerum
Anterius (g), — is bounded above by the lesser wing, below by the
greater wing, and transmits the 3d, 4th, ophthalmic division of the
5th, and the 6th nerves, the ophthalmic vein, branches of the lacri-
mal and middle meningeal arteries, some filaments of the sympathetic
and a process of the dura mater.
Medial (Internal) and Lateral (External) Pterygoid Processes of the
Sphenoid. These wing-like processes descend, i on each side of the body,
and divide each into 2 thin, bony plates (/w), connected together anteriorly,
and presenting the — •
Pterygoid Fossa, — between the plates posteriorly, the origin of the inter-
nal pterygoid muscle.
Scaphoid Fossa, — at the base of the internal plate, serves as the origin of
the tensor veli palatini (tensor palati) muscle.
Hamular Process, — a hook-like projection at the apex of the internal
plate, around which plays the tendon of the tensor palati muscle.
Canalis Pterygoideus or Vidian Canal (14), — at the root of the process,
for the Vidian nerve and vessels.
Triangular Notch, — at the end of the process, articulates with the tu-
berosity of the palate bone.
Development of the Sphenoid. By 14 or 1 6 centres, as follows, — 2 for
the greater wings, 2 for the lesser wings, 2 for the anterior part of the body,
2 for the posterior part of the body, 2 for the medial (internal) pterygoid
processes, and 2 for the sphenoidal conchae (turbinal processes), 2
for the lingulae and 2 for the epipteric bones which usually join the tips
of the great wings. Ossification begins in the 2d fcetal month, and is
completed about the nth year, by the union of the turbinal processes
with the body.
Muscles attached to the Sphenoid. — 12 pairs of muscles are attached
to the sphenoid bone, as follows: —
Orbital muscles, 6 — all except the inferior oblique of the eye.
Muscles of Mastication, 3 — the temporal, external and internal ptery-
goids.
Also the superior constrictor, tensor palati, and laxator tympani, 3.
26 HUMAN ANATOMY
THE ETHMOID BONE
General Characteristics. It is a spongy, light bone, depending from
the ethmoidal notch of the frontal, and from between its orbital plates. It
consists of a body and 2 lateral masses, and is named from the Greek
word r/0/zos, a sieve.
Points on its Body. The body (b) consists of a horizontal or cribriform
plate and presents the —
Crista Galli (c) , — or cock's comb, projecting
upward, for the attachment of the anterior
end of the falx cerebri.
Cribriform Plate (d), — on each side of the
crista galli. It is concave for the olfac-
tory bulbs (/), and perforated for the
transmission of the olfactory nerves, the
nasal branch of the ophthalmic nerve,
and numerous small vessels.
Perpendicular Plate (a), — assists to form
the nasal septum, is usually inclined to
one side, grooved for filaments of the olfac-
tory nerves, and has attached to it the car-
tilage of the nose.
Lateral Masses. They consist of a number of cellular cavities, and each
^ne presents the following points, —
Ethmoid Cells, — the anterior opening by the infundibulum into the
middle meatus of the nose, the posterior into the superior meatus.
Orbital Plate (lamina papyracea, os planum) (h), — helps to form the
inner wall of the orbit and is notched superiorly to form with the
frontal bone the two ethmoidal foramina, or grooves.
Uncinate, or Unciform Process, — descends to articulate with the infe-
rior concha, or turbinal, and forms part of the inner wall of theantrum.
Superior Concha, or Turbinal Process (/),- — is a subdivision of the
posterior part of the middle turbinal process.
Middle Concha, or Turbinal Process (g), — is larger and more curved
than the superior. These processes bound the superior meatus of
the nose.
Articulations, Development, and Muscles. The ethmoid articulates
with 15 bones, viz. — all those of the face except the malar, and the
frontal and sphenoid of the cranium. - It is developed by 3 centres, i for
each lateral mass, and i for the body, ossification being completed about
the 6th year. There are no muscles attached to it.
THE MAXILLARY BONE 27
OSSA NASALIA OR NASAL BONES, (20, Fig. 8)
The Nasal are 2 small bones forming the bridge of the nose by articula-
tion with each other in the median line (4). From side to side they are
convex externally and concave internally, where they are grooved longi-
tudinally for the external branch of the naso-ciliary, or nasal nerve and
some small arteries. They are perforated about the
centre by a foramen (i), for a small tributary to the
facial vein. The superior border (2) articulates with
the nasal notch of the frontal bone; the inferior bor-
der (3) serves for the attachment of the lateral car-
tilage of the nose. The external border (5) articu-
lates with the nasal process of the maxilla; the in-
ternal border (4) with its fellow, with the nasal spine
of the frontal above and with the ethmoid bone below.
They are each developed by one centre of ossification,
and have no muscles attached to them except a few
fibres of the occipito-frontalis.
THE MAXILLA, (18, Fig. 8)
The Maxillae are 2 hollow bones, together forming the upper jaw.
Each bone consists of 4 processes, and a body which possesses interiorly
a large cavity, the sinus maxillaris, or antrum of Highmore.
Antrum of Highmore ja a tetrahedral oa_yjiy in the body of the bone,
whichjpj3ens into the middle meatus of the nose by an aperture which is
very small in the recent subject, admitting only a small probe. Its walls
are very thin, and are covered internally by mucous membrane. It pre-
sents~the —
Aperture, — partly closed by the articulation of the uncinate, or unciform
process of the ethmoid with the ethmoidal process of the inferior
turbinal, and that of the maxillary process of the palate with a
fissure in the maxilla; also by the maxillary process of the inferior
turbinal which hooks over the lower edge of the orifice.
Posterior Dental Canals, — on the posterior wall of the cavity.
Processes, — in its floor, formed by the alveoli of the ist and 2d molar
teeth, the roots of which occasionally perforate it.
Other Points presented by the body. The body has 4 surfaces, the
facial externally, the zygomatic posteriorly, the orbital superiorly, and an
internal surface forming part of the outer wall of the nose and the cavity
of the mouth. The anterior or facial surface presents the —
28
HUMAN ANATOMY
FIG.
Incisive Fossa (2), — on the facial surface, above the incisor sockets, for
the origin of the depressor alae nasi muscle.
Canine Fossa (i), — more externally, for the levator anguli oris muscle.
Infraorbital Foramen (3), — above the canine fossa, transmitting the
infraorbital vessels and nerve, from the infraorbital canal in the orbital
surface of the bone.
Maxillary Tuberosity (7), — articulates with the tuberosity of the palate
bone. The nasal surface presents —
Conchal or Turbinal Crests, — inferior
and superior, for articulation with
inferior and middle conchae, bound-
ing horizontal grooves which cor-
respond to the meati of the nose.
Vertical Grooves, — on the inner sur-
face, one, the lacrimal, assisting
to form the nasal duct, the other,
pterygo-palatine, to form the ptery-
go-palatine, or posterior palatine
canal.
Rough Surface, — for articulation with
the palate bone.
Orbital Surface, — articulating with
the lacrimal, ethmoid, and palate
bones interiorly, partly bounding
the spheno-maxillary fissure exteriorly, and forming the lower mar-
gin of the orbit anteriorly.
Infraorbital Groove (n), — along the orbital surface, ending in the infra-
orbital canal and foramen. (See above.)
Depression, — for the origin of the inferior oblique muscle of the eye.
Processes of the maxilla are 4 in number, as follows: —
MALAR or ZYGOMATIC PROCESS (4, 5), — is triangular, looks outward from
the body, and is rough for articulation with the malar bone.
NASAL or FRONTAL PROCESS (8), — is thin anteriorly and serrated superiorly
(12) for articulation with the nasal bone; posteriorly it is smooth and
articulates with the lacrimal. It presents the —
Conchal or Turbinal Crests, — superior and inferior, the former articu-
lating with the middle concha or turbinal process of the ethmoid
bone.
Outer Surface, — gives origin to the orbicularis palpebrarum and levator
labii superioris alaeque nasi muscles, and the tendo oculi.
THE LACRIMAL BONE 2Q
Lacrimal Groove, — on the posterior border (9), helping to form the nasal
canal.
ALVEOLAR PROCESS (6), — forms the curved line of the teeth, and presents
— Alevoli, — or sockets, for 8 teeth in the adult, 5 in the child.
PALATINE PROCESS, — forms part of the floor of the nasal cavity, and the
roof of the mouth. It articulates with the vomer, the palate bone,
and with its fellow process, and presents the —
Incisive Foramen, or Foramen of Stenson, — leading into the anterior
palatine canal, for the terminal branches of the posterior palatine
arteries.
Foramina of Scar pa, 2, — transmitting the naso-palatine nerves.
Groove, — on the under surface, for the protection of the vessels and
nerves.
Orifice, — of the posterior palatine canal, at the posterior end.
Nasal Crest, — at the articulation of the two processes with the vomer.
Anterior Nasal Spine (10), — the anterior extremity of the nasal crest.
Articulations and Development. The maxilla articulates with 9
bones,— the frontal (12), ethmoid (14), vomer (13), nasal (15), lacrimal,
malar, palate, inferior turbinal, and opposite maxilla. It is developed
probably by 4 centres, — i for the facial and nasal parts, another for the
orbital and malar, a 3d for the incisive, and a 4th for the palate portion.
Muscles attached to it, are n, viz. — the orbicularis palpebrarum, and
levator anguli oris alaeque nasi, 2, to the nasal process; — the levator labii
superioris, levator anguli oris, compressor naris, depres-
sor alae nasi, orbicularis oris, and inferior oblique of the
eye, 6, to the body; — the buccinator, i, to the alveolar
process; — the masseter, i, to the malar process; — and
the external pterygoid, i, to the tuberosity.
THE OSSA LACRIMALIA OR LACRIMAL BONES
The Lacrimal are 2 small quadrilateral bones, situated
in the anterior part of the inner wall of the orbit. Each
bone presents a —
Groove (3), — on the external surface, forming part of the nasal canal.
Ridge (i), — also externally, for attachment of the tensor tarsi muscle.
Furrow, — internally, corresponding to the ridge on the external surface.
Hamular Process (2), — projecting forwards around the nasaj canal.
Superior Border (8),— articulates with the internal angular process of
the frontal bone.
30 HUMAN ANATOMY
Inferior Border (9), — articulates anteriorly with the lacrimal process
of the inferior turbinal bone.
Anterior Border (6), — articulates with the nasal process of the maxilla.
Posterior Border (7), — articulates with the orbital plate of the ethmoid
bone.
Internal Surface, — closes the anterior ethmoidal cells.
Articulations, Development, and Muscles. The lacrimal articu-
lates with 4 bones, — the frontal, ethmoid, maxilla, and inferior turbinal.
It is developed from i centre, and has but i muscle attached to it, the tensor
tarsi or Homer's muscle.
THE OSSA ZYGOMATICA, OR MALAR BONES, (14, Fig. 8)
The Malar or cheek bones are situated at the outer and upper part of the
face, aiding to form the cavities of the orbits and the temporal and
zygomatic fossae. Each bone presents 3 surfaces, 3 processes and 3
borders.
The Orbital surface (c) forming the lateral and front part of the orbit,
is concave laterally; it is bounded in front by the margin of the orbit (6)
and behind by the rough orbital border. About the
FIG. 1 8. middle of this surface is seen the orbital ends of the
Zygomatico-facial, or malar, canals. The Zygomatic,
or infratemporal surface forms the front end of the
zygomatic arch. The facial surface is subcutaneous and
is also known as the malar surface or malar tuberosity;
it presents the outer ends of the two small malar
canals. Orbital, or fronto-sphenoidal process (a) in
man, and those animals having a closed orbit, articu-
lates with the great wing of the sphenoid and the orbital process of the
frontal bone. It forms the upper end of the temporal border (h) which
forms the anterior boundary of the temporal fossa and is continuous with
the temporal ridge of the skull. This border terminates below and
behind in the zygomatic or temporal process (/), which is rough for ar-
ticulation with the zygomatic process of the temporal bone. The lower
or masseteric border (g) is rough for attachment of the masseter and
zygomatic muscles. It terminates medially in the long slender maxillary
process (d) which is very rough for articulation with the maxilla and
forms most of the lower margin of the orbit (&).
Articulations, Development, and Muscles. The malar articulates
with 4 bones, — the frontal, sphenoid, temporal, and maxilla. It is
THE PALATE BONES 3!
developed by one centre of ossification, and has 4 muscles attached to
it, — the levator labii superioris, zygomaticus major and minor, and the
masseter.
THE PALATE BONES
The Palate Bones are 2 L-shaped bones, situated posteriorly in the
nares. Each bone assists in forming the floor and outer wall of the
nose, the roof of the mouth, the floor of the orbit, the inner wall of the an-
trum, the zygomatic, spheno-palatine, and pterygoid fossae, and presents
the following points : —
HORIZONTAL PLATE (a), completes the nasal floor and hard palate; has a —
Ridge, — on the inferior surface, for the tensor palati aponeurosis.
Groove, — assisting to form the posterior palatine canal.
Foramina, — transmitting the anterior and posterior
palatine nerves.
Anterior Border, — is serrated, for articulation with
the maxilla.
Posterior Border, — is free and concave, for the at-
tachment of the soft palate.
Inner Border (d), — is thick, and articulates with
its fellow, forming a groove for the reception
of the vomer. Its posterior extremity is the —
Posterior Nasal Spine, — for the origin of the azygo
uvulae muscle.
VERTICAL PLATE (6), a broad and thick lamella, pre-
sents the following: —
Ridge for Middle Concha, — on the inner surface. Below it is the —
Ridge for Inferior Concha (g), — dividing the middle meatus of the nose
from the inferior, and articulating with the inferior concha or turbinal
bone.
Posterior Border, — articulates with the pterygoid process of the sphenoid.
Groove, — on the external surface, helping to form the posterior palatine,
or pterygo-palatine canal.
Two Smooth S urfaces — externally, one forming the inner wall of the
spheno-palatine or pterygo-palatine fossa; the other, part of the inner
wall of the maxillary antrum.
Two Rough Surfaces— also externally, one for articulation with the
maxilla; the other with the pterygoid process of the sphenoid.
Deep Notch, — which by articulation with the sphenoid bone, forms the
spheno-palatine foramen (A),— for the spheno-palatine vessels and the
superior nasal and palatine nerves.
32 HUMAN ANATOMY
TUBEROSITY OR PYRAMIDAL PROCESS (c), is wedged into the notch between
the plates of the pterygoid process of the sphenoid, with which it
articulates laterally. In it are the —
Palatine Foramina, — for the anterior, middle and posterior palatine
nerves.
Posterior Surface, — aids in forming the pterygoid fossa.
ORBITAL PROCESS (*), — triangular in shape, large and hollow. It has —
Three Articular Surfaces, — for the maxiJla, sphenoid, and ethmoid.
Two Free Surfaces, — the orbital forming, part of the floor of the orbit, the
external aiding to form the spheno-palatine fossa.
Rounded Border, — forms a part of the spheno-maxillary fissure.
SPHENOIDAL PROCESS (j), projects backward, articulates superiorly with
the body of the sphenoid, and externally with the pterygoid process of
the sphenoid. On its upper surface is a —
Groove, — which assists in forming the spheno-palatine or pharyngeal
canal.
Inner Surface, — forms part of the outer wall of the nasal fossa.
Articulations, Development, and Muscles. The palate articulates
with 6 bones, — the sphenoid, ethmoid, vomer, maxilla, inferior turbinal,
and its fellow palate bone. It is developed by one centre at the junction
of the two plates. There are 4 muscles attached to it, — the azygos uvulae,
internal pterygoid, superior constrictor and tensor palati.
THE CONCH^E NASALES INFERIORES OR THE INFERIOR
TURBINAL BONES
The Inferior Turbinal Bones are 2 thin, curved osseous plates situated in
the nasal fossae, their convex surfaces presenting inwardly. Each bone is
pIG. 20. attached above to the inferior turbinal crests
of the maxillary and palate bones, and presents
the following, viz. —
Lacrimal Process (3), — aiding to form the
nasal duct, by articulation with the lacri-
mal and maxilla.
Ethmoidal Process (i), — articulating with the unciform process of the
ethmoid, thus helping to partially close the aperture of the antrum.
Maxillary Process (4), — also helps to partially close the aperture of the
maxillary antrum, by hooking (7) over the lower edge of that orifice.
Free Border (5), — below, coming to about % inch above the floor of the
nose.
THE VOMER AND MANDIBLE 33
Articulations, Development and Muscles. The inferior turbinal ar-
ticulates with 4 bones, the ethmoid, lacrimal, palate, and maxilla. It
is developed by one centre, and has no muscles attached to it.
THE VOMER
The Vomer (plough-share) forms the postero-inferior part of the nasal
septum, but is usually bent to one side. Its —
Superior Border (i, 2), — has a groove and two alae or wings, for articula-
tion with the rostrum and vaginal proc-
esses of the sphenoid bone.
Anterior Border (3), — is grooved for the
ethmoidal plate and the jiasal cartilage.
Inferior Border (4), — the longest, articulates
with the nasal crest of the maxillary and
palate bones.
Posterior Border, — is free and presents toward the pharynx.
Naso-palatine Grooves, — laterally, for the naso-palatine nerves.
Furrows, — on the lateral surfaces (6), for vessels and nerve-filaments.
Articulations, Development and Muscles. The vomer articulates
with 6 bones, — the sphenoid, ethmoid, 2 maxillary, and 2 palate bones.
It is developed by one centre, which appears about the 6th foetal week in
cartilage between two laminie which coalesce after puberty. It has no
muscles attached to it.
THE MANDIBLE, (25, Fig. 8)
General Characteristics. The Mandible is the lower jaw, receives the
inferior teeth, and is the second bone of the body in which ossification
appears, the clavicle being the first. It consists of a body and two rami.
The Body (i) is shaped somewhat like a horseshoe, and presents for
examination the following: —
Alveolar Portion (15), — above the oblique line, containing on its upper
border alveoli for 16 teeth in the adult, for 10 in the child (i, b, c, m).
Symphysis (3), — a vertical ridge on the median line, marking the junc-
tion of the two symmetrical portions of which the bone originally
consisted.
Mental Process, — a prominent triangular eminence, characteristic of
man, forming the chin.
Externally on each side from the symphysis backward, are the —
3
34 HUMAN ANATOMY
Incisive Fossa (4), — above the chin, for the origin of the levator menti.
Meatal Foramen (5), — below the 2d bicuspid alveolus, transmitting the
mental artery and nerve.
External Oblique Line (i), — for the origins of the depressor labii infe-
pIG 22 rioris and depressor anguli
oris muscles from its anterior
half.
Groove (7), — near the angle,
for the facial artery.
Internally, on each side from the
median depression backward,
are the—
Mental Spines, or Genial Tuber-
cles,— the superior for the
genio-hyoglossus muscle; the
inferior for the genio-hyoid.
Mylo-hyoid Ridge, — obliquely backward, for the mylo-hyoid muscle.
Sublingual Fossa, — near the genial tubercles, for the sublingual gland.
Fossa, — below the sublingual, for the anterior belly of the digastric
muscle.
Submandibular Fossa, — below the ridge, for the submandibular gland.
The Rami of the Mandible, the ascending portions of the bone, are 2
in number, and each presents the —
Coronoid Process (10), — anteriorly, for the insertion of the temporal
muscle.
Condylar Process (n), — posteriorly. Its condyle articulates with the
glenoid fossa of the temporal bone, its neck receives the insertion of the
external pterygoid muscle, its tubercle has attached to it the external
lateral ligament of the lower jaw.
Sigmoid Notch (12), — a deep depression separating the above-named
processes from each other, and crossed by the masseteric vessels
and nerve.
Groove, — on the coronoid process internally, and prolonged downward
upon the body, for the attachment of the buccinator muscle.
Ridges, — on the external surface, for the insertion of the masseter.
Lingula or Spix's Spine, — a projection on the margin of mandibular
foramen, for the attachment of the spheno-mandibular ligament.
Mandibular Foramen, or Canal (13), — opening behind the spine, lies
within the ramus and body of the bone for the inferior dental vessels
and nerve. It communicates with each alveolus and with the
mental foramen.
THE ORBITS 35
Mylo-hyoid Groove (14), — below the spine, for the mylo-hyoid vessels and
nerve.
Rough Surface, — behind the groove, for the internal pterygoid muscle.
Angle of the Jaw (8), — at the junction of the posterior border of the
ramus with the inferior border of the body, for the insertion of the
masseter and internal pterygoid muscles, and the stylo-mandibular
ligament.
Articulations and Development. It articulates with one pair of bones,
— the temporal. It is the earliest formed bone in the body except the
clavicle, and is probably developed by 2 centres, one for each lateral half,
the two halves coalescing at the symphysis about the ist year of age.
In adult life the ramus arises almost vertically from the body, and the
dental canal lies about the middle of the body. In old age the ramus
seems to extend obliquely backward, the angle becoming very obtuse;
and the alveolar portion being absorbed, the dental canal is near the
superior border.
Muscles attached to the Mandible, — number 15 pairs, — the masseter,
internal and external pterygoids and temporal, 4, to the ramus; — the
genio-hyo-glossus, genio-hyoid, mylo-hyoid, digastric, and superior con-
strictor, 5, to the internal surface of the body; — the depressor labii inferioris,
depressor anguli oris, levator menti, orbicularis oris, platysma myoides,
and buccinator, 6, to the external surface of the body.
'M T-E ORBITS
The Orbits are 2 conoidal cavities, situated between the forehead and
the face, their bases outward, their apices pointing backward, the lines of
axial prolongation meeting at the sella turcica of the sphenoid bone. They
contain the organs of vision with their appendages, and are each formed
by 7 bones, — the frontal (i), ethmoid (2), sphenoid (3, 4, 5), lacrimal
(6), maxilla (7), palate (8), and malar (9), of which the first three are com-
mon to both orbits. Each orbit communicates with i cavity and 4 fossae,
as follows, viz. — •
Cavity of the cranium, — by the optic foramen (u) and superior orbital
or sphenoidal fissure (10).
Fossa (4), — the nasal, temporal, zygomatic, and spheno-palatine or
spheno-maxillary, — by the nasal duct (12) and the inferior orbital or
spheno-maxillary fissure (13).
Foramina communicating with each orbit are 9 in number, — the optic
foramen (u), superior orbital or sphenoidal fissure (10), anterior (21) and
36
HUMAN ANATOMY
FIG. 23.
posterior (22) ethmoidal foramina, supraorbital (14), infraorbital (15),
and zygomatico-facial and temporal or malar foramina (16), the nasal
or lacrimal canal (12), and the inferior orbital or spheno-maxillary
fissure (13).
Roof of the Orbit is formed by the orbital plate of the frontal bone ante-
riorly (i), and the lesser wing of the sphenoid (4) posteriorly. It is con-
cave, and presents the —
Lacrimal Fossa (17), — at its outer angle, for the lacrimal gland.
Fovea Trochlearis (18), — at the
inner angle, for the pulley
of the superior oblique.
Floor of the Orbit is formed
by the orbital surface of the
maxilla (7), and the orbital
process of the malar (9) and pal-
ate bones (8).
It is nearly flat and presents the—
Palato-maxillary Suture, — pos-
teriorly.
Infraorbital Canal,— anteriorly.
Infraorbital Groove (9), — pos-
teriorly.
Medial or Inner Wall of the
Orbit is formed by the nasal
process of the maxilla (20), the
lacrimal (6), the orbital plate or lamina papyracea of the ethmoid (2),
and the body of the sphenoid (3). It presents —
A Groove, — for the lacrimal sac, and the Lacrimal Crest, anteriorly.
2 Sutures, — the ethmo-lacrimal, and the ethmo-sphenoidal.
Lateral or Outer Wall of the Orbit is formed by the orbital process of the
malar bone (9), and the greater wing of the sphenoid (5). It presents the
Orifices (16) of the zygomatico-facial and zygomatico- temporal or malar
canals, and the Spheno-malar Suture.
Angles of the Orbit present the following points: —
IN THE SUPERIOR EXTERNAL ANGLE:
Superior Orbital or Sphenoidal Fissure (10), or Foramen Lacerum
Anterius, — transmits the 3d, 4th, ophthalmic division of the 5th,
and the 6th nerves, the ophthalmic vein, branches of the lacrimal
THE FOSS.E OF THE SKULL 37
and middle meningeal arteries, filaments of the sympathetic nerve,
and a process of the dura mater.
Articulations, — the fronto-malar, and fronto-sphenoidal.
IN THE SUPERIOR INTERNAL ANGLE: —
Suture, — the lachrymo-ethmo-frontal, in which are the following fora-
mina:
Anterior Ethmoidal Foramen (21), — transmitting the anterior ethmoidal
artery and the nasal nerve.
Posterior Ethmoidal For amen (22), — transmitting the posterior ethmoidal
artery and vein.
IN THE INFERIOR EXTERNAL ANGLE:
Inferior Orbital or Spheno-maxittary Fissure (13) — (described under the
Zygomatic Fossa).
IN THE INFERIOR INTERNAL ANGLE: —
A Suture, — the ethmo-maxillo-palato-lacrimal.
Other Points connected with the Orbit are two, the supraorbital notch
and the optic foramen, as follows: —
Supraorbital Notch or Foramen (14), — at the junction of the inner and
middle thirds of the upper circumference, transmitting the supra-
orbital artery, veins, and nerve. A line prolonged from this notch
through the interval between the bicuspid teeth of either jaw, will
cross both the infraorbital and mental foramina, and the canine fossa
of the maxilla.
Optic Foramen (n), — at the apex, is formed by the 2 roots of the lesser
wing of the sphenoid, and transmits the optic nerve and the ophthal-
mic artery. From around its margin arises a tendinous ring, the
common origin of the 4 recti muscles of the eye.
Muscles arising within the Orbit are the 4 recti and 2 oblique of the eye,
the levator palpebrae, and the tensor tarsi (8 in all).
THE FOSSJE
The Nasal Fossae together form the cavity of the nose, being separated
from each other by the Septum Nasi (n). They open in front by the
anterior nares, behind by the posterior nares; and extend from the palate
processes of the maxilla and palate bones (17), upward to the base of the
cranium. They are formed by 14 bones, — the ethmoid, sphenoid,
frontal, vomer, 2 nasal, 2 maxillae, 2 lacrimal, 2 palate and 2 inferior con-
chae or turbinal.
The Septum Nasi (n) forms the inner wall of each nasal fossa, and is
formed chiefly by the perpendicular plate of the ethmoid bone, the vomer.
38 HUMAN ANATOMY
and the triangular cartilage of the septum; to a less extent by 5 other bones,
— the rostrum of the sphenoid, the nasal spine of the frontal, and the crests
of the nasal, palate, and maxillary bones.
Points presented by each Nasal Fossa are as follows: —
ON THE ROOF : —
Openings, — posteriorly, into the sphenoidal sinuses.
Olfactory Foramina, — and the Nasal Slit, -in the cribriform plate of the
ethmoid bone.
ON THE FLOOR: —
Orifice, — of the anterior palatine canal.
Suture, — between the bones forming the hard palate.
Nasal Spine, — anterior and posterior, and the Ridge connecting them.
ON THE LATERAL OR OUTER WALL,
FIG. 24. from above downward: —
Superior Concha or Turbinal
Process, — of the ethmoid.
Superior Meatus of the nose —
into which open 3 orifices, —
those of the posterior eth-
moidal and the sphenoidal
sinuses, and the sphenopala-
tine foramen.
Middle Concha or Turbinal
Process (7), — of the ethmoid.
Middle Meatus of the nose, — •
into which open 2 orifices,
those of the antrum (14) and
infundibulum, the latter draining the anterior ethmoidal cells (8),
and the frontal sinus.
Inferior Concha or Turbinal Bone (10), — below which is the —
Inferior Meatus — of the nose, the largest; into it open 2 orifices, those
of the lacrimal and anterior palatine canals. To these may be
added the apertura pyraformis (anterior) and posterior nares.
The Temporal Fossa. Situated on each side of the cranium, it is shallow
above and behind, but deep in front and below, and is formed by parts
of 5 bones, — the frontal, sphenoid, temporal, parietal, and malar. It is
bounded above and behind by the temporal ridge, in front by the malar,
frontal, and sphenoid bones, and below by the zygoma and the pterygoid
bounded above and behind by the temporal ridge, in front by the malar,
frontal, and sphenoid bones, and below by the zygoma and the pterygoid
SUTURES AND FONTANELLES 39
ridge on the greater wing of the sphenoid. It is traversed by 6 sutures, —
the spheno-malar, spheno-frontal, spheno-parietal, spheno-temporal,
frontal-parietal, and temporo-parietal. It opens below into the zygomatic
fossa; and lodges the temporal muscle, and the deep temporal vessels.
The Zygomatic Fossa extends downward from the temporal fossa, and
is bounded —
In front, — by the tuberosity of the maxilla.
Laterally or Externally, — by the zygoma, and the ramus of the mandible.
Medially or Internally, — by the lateral or external plate of the pterygoid
process.
Above, — by the temporal fossa, the squamous portion of the temporal
bone and the greater wing of the sphenoid.
Below, — by the alveolar border of the mandible bone.
Fissures opening into the Zygomatic Fossa are two, the —
Inferior Orbital or Spheno-maxillary Fissure, — between the greater wing
of the sphenoid externally, and the maxilla and palate bones medially
or internally. It connects the orbit with the zygomatic, temporal, and
spheno-palatine fossse; and transmits the infraorbital artery, the maxil-
lary nerve and its orbital branches, and the ascending branches of
Meckel's ganglion.
Pterygo-maxillary Fissure, — between the tuberosity of the maxilla and
the pterygoid process of the sphenoid. It transmits branches of
the internal maxillary artery, and connects the zygomatic fossa with
the spheno-palatine.
The Spheno-palatine Fossa is a triangular cavity between the pterygoid
process of the sphenoid bone and the tuberosity of the maxilla, and is
situated at the junction of the spheno-maxillary, pterygo-maxillary, and
sphenoidal fissures. Into it open —
3 FOSSCE, — the orbital, zygomatic, and nasal.
2 Cavities, — the cranial, and buccal.
5 Foramina, — the Vidian and spheno-palatine or pharyngeal canals and
the foramen rotundum, posteriorly; the spheno-palatine foramen on
the inner wall; and the posterior palatine canal interiorly, occasion-
ally also the accessory palatine canals.
THE SUTURES AND FONTANELLES
The Sutures of the Skull are 13 in number, as follows: —
At the vertex of the skull are 3, the —
40 HUMAN ANATOMY
Sagittal or Interparietal, — formed by the junction of the two parietal
bones.
Metopic, between the halves of the Frontal, may persist until late in
life.
Coronal or Fronto-parietal, — extends transversely across the vertex
of the skull anteriorly.
Lambdoid or Occipito-parietal, — extends transversely across the vertex
of the skull posteriorly.
At the sides of the skull are 5, the —
Fronto-malar and Fronto-sphenoidal, — anteriorly.
Spheno- parietal, Squamo- parietal and Masto- parietal, — posteriorly.
At the base of the skull are 5, the — •
Basilar, — in the central line of the base.
Petro-occipital, Masto-occipital, Petro-sphenoidal and Squamo- sphenoidal
— on each side.
The Facial Sutures are very numerous, the most important being the
following: —
Zygomatic Suture, — at the temporo-malar articulation.
Transverse Suture, — extending from one external angular process of
the frontal bone across to the other, and connecting that bone with
the malar, sphenoid, ethmoid, lacrimal, maxillary, and nasal bones.
Symphysis of the Chin, — the site of a fcetal suture.
The Sutures are formed by dentations of the external tables inter-
digitating with each other, the adjacent edges of the internal tables lying
in unjoined proximity. The sutures are not formed until a long time
after the formation of the skull, probably to permit of the marginal growth
of the bones.
The Fontanelles are 6 membranous intervals in the infant's skull,
corresponding in situation with the angles of the two parietal bones.
They are as follows: —
Anterior, — at the junction of the sagittal and coronal intervals.
Posterior, — at the junction of the sagittal and lambdoid intervals.
Lateral Fontanelles, 4, — two at the anterior inferior angles, and two at
the posterior inferior angles of the parietal bones.
The Ossa Suturarum (Wormian Bones) are supernumerary small pieces
of bone, irregularly shaped, and developed by special centres in unclosed
portions of the cranial sutures and fontanelles, being most frequent in the
lambdoid suture.
FORAMINA AT BASE OF SKULL 4!
The Hyoid Bone is shaped like a horse-shoe and has no articulation with
the skeleton, but supports the tongue. It consists of a Body, two greater
and two lesser Cornua or horns. On the body is a Crucial Ridge, with a
Tubercle at the centre. It is developed by 5 centres, — one for the body
and one for each horn. Attached to it are 10 muscles, 3 ligaments and i
membrane, as follows: —
To the Body or Basi-hyal, — the genio-, mylo-, stylo-, sterno-, thyro-,
omo-hyoid, the genio-hyo-glossus, and the hyo-glossus muscles; also
the pulley of the digastric, the hyo-epiglottic ligament, and the thyro-
hyoid membrane.
To the Greater Cornu, or thyro-hyal, — the hyo-glossus, middle constrictor
muscles, and part of the thyro-hyoid; also the thyro-hyoid ligament.
To the Lesser Cornu, or cerato-hyal, — the stylo-hyoid ligament.
FORAMINA AT THE BASE OF THE SKULL
with the various structures transmitted by each foramen
Internally, the Anterior Fossa has i single and 4 pairs, viz. —
, Foramen Cacum, — lodges a fold of dura mater, and transmits a vein to
the longitudinal sinus.
Ethmoidal Fissure, — the nasal branch of the 5th nerve.
Olfactory, — olfactory nerves, and nasal branches of the ethmoidal
arteries.
Anterior Ethmoidal, — ant. ethmoidal artery and the nasal br. of the 5th
nerve.
Posterior Ethmoidal, — posterior ethmoidal artery and vein.
Middle Fossae contain 10 foramina in each fossa, viz. —
/ Optic Foramen, — optic nerve and ophthalmic artery.
rj Foramen Lacerum Anterius, Superior Orbital or Sphenoidal Fissure, — the
3d, 4th, ophthalmic division of the 5th, and the 6th cranial nerves and
filaments of the sympathetic; ophthalmic vein, a branch of the
lacrimal artery, orbital branches of the middle meningeal artery,
and a process of dura mater.
Foramen Rotundum, — maxillary division of the 5th nerve.
foramen Vesalii, — a small vein. This foramen is often absent.
Foramen Ovale, — mandibular division of the 5th nerve, lesser petrosal
nerve, and the small meningeal branch of the internal maxillary artery.
Foramen Spinosum, — middle meningeal artery, meningeal veins, and
sympathetic filaments from the cavernous plexus.
Foramen Lacerum Medium, is not a true foramen in that it is completely
42 HUMAN ANATOMY
blocked by fibro-cartilage, the cerebral surface of this cartilage is
deeply grooved or may even be tunneled from behind forwards
by — internal carotid artery, carotid plexus, Vidian nerve, and artery.
Small Foramina, — for the small and external superf. petrosal nerves.
Hiatus Canalisfacialis Fallopil, — large petrosal nerve, and a branch of
middle meningeal artery.
Posterior Fossa contains 6 pairs and i single foramen, viz. —
Meatus Acusticus or Auditor ins Intermts, — facial and auditory nerves,
auditory artery.
Aqu&ductus Vestibuli, — small artery and vein, process of dura mater.
Foramen Lacerum Posterius (Jugular Foramen) , — the glosso-phary ngeal,
pneumo-gastric, and spinal accessory nerves, internal jugular vein,
meningeal branches of the ascending pharyngeal and occipital
arteries.
; Mastoid Foramen (often absent), — a small vein, also occasionally the
mastoid artery.
Anterior Condylar or Hypoglossal Foramen, — hypoglossal nerve, menin-
geal branch from the ascending pharyngeal artery.
Posterior Condylar Foramen (often absent), — posterior condylar vein.
Foramen Magnum, medulla oblongata and its membranes, the vertebral
arteries, and the spinal accessory (n. accessorius) nerves.
Externally, at the base of the skull, from the front backward, are 22 fora-
mina on each side, and i single, the foramen magnum, as follows: —
Foramina of Scar pa (2) (Anterior Palatine), 2 in the median line, — for
the naso-palatine nerves.
Foramina of Stenson (2) (Incisive}, laterally, — terminal branches of the
posterior palatine arteries.
Posterior Palatine (3), — posterior palatine vessels, anterior palatine
nerve.
Accessory Palatine Foramina (i or 2 on each side), — the middle and pos-
terior (small) palatine nerves.
Orifice of the Posterior Naris, — air to the lungs.
Ptery go- palatine Foramen, — pterygo-palatine vessels.
Foramen Ovale (10), — mandibular nerve.
Orifice of the Vidian or Pierygoid Canal, — the Vidian nerve and vessels.
Foramen Spinosum (n), — middle meningeal artery.
Foramen Lacerum Medium (12), — see under Middle Fossae.
Opening for the Eustachian Tube.— SLIT to the middle ear.
Opening of Tensor Tympani Canal, — the tensor tympani muscle.
TKE BASILAR SURFACE OF SKULL
43
Glaserian Fissure, — laxator tympani muscle, tympanic artery; lodges the
processus gracilis of the malleus.
Carotid Foramen (19), — internal carotid artery, nerves from the superior
cervical ganglion to the carotid plexus.
Anterior Condylar or Hypoglossal Foramen, — Hypoglossal nerve.
Foramen Lacerum Poster ins (20), — see under Posterior Fossa.
PIG. 25.
Foramen for Jacobson's Nerve, — tympanic branch of the glosso-pharyn-
geal.
Foramen for Arnold's Nerve, — auricular branch of the pneumogastric.
Opening of the Aquaduclus Cochlea, — artery and vein to the cochlea.
Stylo-mastoid Foramen (18), — facial nerve, stylo-mastoid artery.
Auricular Fissure, — exit of Arnold's nerve, auricular branch of the
vagus.
44 HUMAN ANATOMY
Posterior Condylar Foramen, — see under Posterior Fossa.
Foramen Magnum (23), — see under Posterior Fossa.
Face presents 4 pairs, viz. —
Supraorbital Foramen or Notch, — supraorbital artery, vein, and nerve.
Infraorbital Foramen, — inf raorbital artery, vein and nerve.
Orifice of the Anterior Naris or Apertura pyraformis, — air to the lungs.
Mental Foramen, mental nerve and artery.
POINTS AT THE BASE OF THE SKULL
illustrated and numbered on fig. 25
Median Suture (i), — of the palatine vault, crucial in form posteriorly.
Posterior Nasal Spine (4), — the posterior border of the palatine vault.
Vomer (5), — or nasal septum, its posterior border.
Hamular Process (6), — of the pterygoid process of the sphenoid bone.
Internal Plate (7), — of the pterygoid process of the sphenoid bone.
External Plate (8), — of the pterygoid process of the sphenoid bone.
Scaphoid Fossa (9), — on the internal plate (7) of the pterygoid process.
Zygoma (13), — or zygomatic process of the temporal bone.
Basilar Suture (14), — between the occipital and sphenoid bones.
Basilar Process (22), — of the occipital bone.
Articular or Clenoid Fossa (15), — for the mandible.
Glaserian Fissure, — squamo-tympanic.
External Auditory Meatus (16). — opening of the ext. auditory canal.
Mastoid Process (17), — of the temporal bone.
Styloid Process (18), — of the temporal bone.
Occipital Condyles (21), — articulate with the atlas.
External Occipital or Nuchal Crest (24), — terminating at the protuberance.
Inferior Nuchal or Curved Li.ies (25), — of the occipital bone.
BONES OF THE EXTREMITIES
THE SHOULDER
Bones forming the Shoulder are the clavicle and scapula connecting the
arm with the trunk, and in this respect homologous to the innominate bone
in the lower part of the body, being sometimes called the shoulder girdlet
as the innominate bones arc called the pelvic girdle.
CLAVICLE AND SCAPULA 45
The Clavicle, collar- or key-bone, is a short bone by structure, having no
medullary canal. It is curved like the letter/, its inner two-thirds being
prismatic and convex anteriorly; its outer third flattened, and concave
anteriorly. It is placed horizontally between the sternum and the
scapula and is the most elastic bone
in the body. It presents, from
within outward, the following points,
viz. —
Facets (6), — for articulation with
the sternum and the cartilage of
the 1st rib, at its sternal end.
Upper border extending the length of the medial two-thirds, rough at its
sternal end for attachment of the sterno-cleido-mastoid. Laterally it
becomes lost on the smooth flat upper surface of the acromial third.
UNDER SURFACE PRESENTS: — •
Impression (2), — for the rhomboid, or costo-clavicular ligament.
Groove (i), — on the lower surface, for the subclavius muscle.
Tubercle, — for the conoid part of the costordavicular ligament.
Oblique Line, — for the trapezoid part of the same ligament.
Facet (7), — on the acromial end, for articulation with the scapula.
Nutrient For amen, — in the subclavian groove or in posterior surface, and
runs towards the shoulder.
Anterior Border (5), — Medial two-thirds convex forwards and rough for
attachment of pectoralis major. Lateral third is concave forwards,
presents deltoid tubercle and is rough for attachment of deltoid.
Posterior Border (4), — medial two-thirds concave and not well-defined,
acromial third is con vex back wards and rough for attachment of thetrape-
zius. Medial two-thirds ossify from cartilage, lateral third from membrane.
• The Scapula, or shoulder-blade, is a large, flat, and triangular bone,
situated on the posterior and lateral portion of the thorax, from the 2d rib
to the 7th, inclusive. Its —
VENTER, or anterior surface, presents from within outward, —
Ridges, — giving attachment to the subscapularis muscle.
Marginal Surface,— along the inner border for the attachment of the
serratus magnus muscle.
Subscapular Fossa and Angle, — for the subscapularis muscle.
DORSUM, or posterior surface, presents the following, viz. —
Spine (10), — a bony ridge, which affords attachment to the trapezius
and deltoid muscles, and ends in the acromion process.
Supraspinous Fossa (i), — above the spine, for the^supraspinatus muscle.
0 HUMAN ANATOMY
Infraspinous.Eossa (2), — below the spine, larger than the supraspinous,
convex at its centre, lodges the infraspinatus muscles, and the
nutrient foramen.
Marginal. Surf ace, — along the external border, to which are attached
the teres minor muscle above, the
teres major below, and sometimes
a few fibres of the latissimus dorsi
at the lower angle.
Groove, — crossing the margin, for the
dorsalis scapulae vessels.
Smooth Surface (n), — behind the
root of the spine, over which the
trapezius muscle glides.
ACROMION PROCESS (12), or summit of
the shoulder, extends from the spine,
and projects over the glenoid cavity,
articulating with the clavicle by an
oval facet. It affords attachment to
the deltoid and trapezius muscles, and
by its apex to the coraco-acromial
ligament.
CoRACpip PROCESS (14), or crow's beak,
projects from the upper border and
neck of the bone over the inner and upper part of the glenoid cavity.
Into it is inserted i muscle, the pectoralis minor; the coraco-brachialis
and the short head of the biceps arise from it by a common tendon,
and 3 ligaments are attached to it, — the conoid, trapezoid, and
coraco-acromial.
SUPERIOR BORDER (3) presents the —
Suprascapular Notch (4), — converted into a foramen for the supra-
scapular nerve by the transverse ligament, over which passes the
suprascapular, or transverse scapular artery. The omo-hyoid
muscle is attached to the border just internal to this notch.
AXILLARY BORDER (5) is the thickest, and presents a —
Rough Surface (8), — for the long head of the triceps muscle just below
the glenoid cavity.
Notch, — for circumflex scapular artery.
Groove, — the origin of a part of the subscapularis muscle.
VERTEBRAL BORDER (9) is the longest, and presents an —
Anterior Lip, — for the attachment of the serratus magnus.
Posterior Lip, — for the supra- and infraspinatus muscles.
THE HUMERUS 47
Interspace, — between the lips, for the levator anguli scapulae, the rhom-
boideus minor, and the fibrous arch of the rhomboideus major
muscles.
OTHER POINTS of interest on the bone are the — •
Medial, or Superior Angle, — affords attachment to part of the serratus
magnus, levator anguli scapulae, and supraspinatus muscles.
Inferior Angle (7), — affords attachment to part of the serratus magnus
and teres major muscles, and to a few fibres of the latissimus dorsi.
Glenoid Cavity (6), — at the external angle or head of the bone, a shallow
cavity for the reception of the head of the humerus. It is deepened
by the glenoid ligament which is attached around its margin; and
gives origin to the long head of the biceps flexor cubiti muscle.
Neck, — is the contracted part of the bone behind the glenoid cavity;
from it arises the anterior root of the coracoid process.
THE ARM
The Humerus is the only bone in the arm, and articulates with the
scapula above, and with the ulna and radius below. It presents for
examination a shaft and two extremities, on which are the following
points, viz. —
Head (b), — is nearly hemispherical, and smooth for articulation with
the glenoid cavity of the scapula.
Anatomical Neck'(c), — is a constriction in the bone, just below the head,
for the attachment of the capsular ligament.
Greater Tuber osity, or Tubercle (d), — has 3 small facets for the inser-
tions of the supraspinatus, infraspinatus, and teres minor muscles.
Lesser Tuberosity, or Tubercle (e), — on the inner side of the bone, gives
insertion to the subscapularis muscle.
Bicipital, or Intertubercular Groove (/), — lies vertically between the
tuberosities for the upper third of the bone and lodges the tendon
of the long head of the biceps flexor cubiti. Into its inner or medial
lip (h) are inserted the teres major and latissimus dorsi muscles,
while its outer or lateral lip (g) receives the insertion of the tendon
of the pectoralis major, which covers the groove.
Surgical Neck, — is situated immediately below the tuberosities, and is
a slight constriction in the upper part of the shaft.
Shaft (a), — is cylindrical above, prismatic and flattened below.
Rough Surface (i), — for the insertion of the deltoid muscle, about the
middle of the external surface of the shaft.
Musculo-spiral Groove, or Sulcus n. Radialis (a), — lodging the musculo-
spiral, or radial, nerve and the superior profunda artery, is situated
HUMAN ANATOMY
on the posterior surface of the shaft, separating the origins of tne
outer and inner heads of the triceps muscle.
FIG 28 Orifice (j), — of the nutrient canal, about the middle oi
the shaft, on its internal border.
Condylar Ridges, — internal or medial (/>) and external
or lateral (0), arising from the respective condyles.
extending upward along the shaft.
Lateral or External Condyle (m),- -gives attachment to
the external lateral ligament and the extensor and
supinator group of muscles.
Medial or Internal Condyle («), — lower and more promi-
nent lhan the other, gives attachment to the internal
lateral ligament and the flexor and pronator group of
muscles of the forearm.
Capitellum (&), — forms the outer or lateral part of the
inferior articular surface; for articulation with the
radius, it is on the front of the lateral condyle, above it
is the radial fossa.
Trochlcar Surface (1), — articulates with the greater
sigmoid cavity (incisura semilunaris) of the ulna; is a
deep depression between two borders and extends
from the anterior to the posterior surface of the bone.
Coronoid Fossa, — above the front of- the trochlear sur-
face, receives the coronoid process of the ulna when
the forearm is flexed.
Olecranon Fossa (q), — above the back part of the trochlea, receives the
tip of the olecranon process, when the forearm is extended.
THE FOREARM
The skeleton of the forearm is -composed of 2 bones.
The Ulna, or elbow-bone, is the principal bone of the forearm. It is
larger and longer than the radius, forming the greater portion of the
articulation with the humerus. It does not enter into the formation of the
wrist-joint, being excluded therefrom by an interarticular nbro-cartilage.
It presents for examination a shaft and two extremities, on which are
the following points: —
Olecranon Process (4), — at the upper extremity, forming the elbow. It
is curved forward, its apex being received into the olecranon .fossa of
the humerus when the forearm is extended. Its posterior surface
gives insertion to the tendon of the triceps. In its function and
structure it resembles the patella.
THE ULNA AND RADIUS
49
Coronoid Process (5), — below the olecranon projects forward forming
the Tuberosity (3), its apex being received into the coronoid fossa
of the humerus when the forearm is flexed. Its upper surface
is concave for articulation with the humerus, its lower surface rough
for the insertion of the brachialis anticus muscle. Its inner surface
has a margin for the internal lateral ligament, a tubercle for the flexor
sublimis digitoium, and a ridge for the pronator radii teres.
Greater Sigmoid Cavity, or Incisura Semilunaris (2), — lies between the
processes, and is divided by a vertical ridge into two unequal parts.
It articulates with the _trochlear surface of the
humerus. *IG- 29'
Lesser Sigmoid Cavity or Incisura Radialis (3),— lies
external to the coronoid process; is oval and con-
cave, articulating with the head of the radius, and
giving attachment to the orbicular ligament.
Shaft (i), — large and prismatic above, smaller and
rounded below, has the Nutrient Foramen (6) on its
anterior surface (i), and a prominent margin ex-
ternally, to which is attached the interosseous
membrane (7). It gives attachment to 9 of the 12
muscles of the forearm.
Head (8), — at the carpal end, articulates with the
lesser sigmoid cavity of the radius, and the fibro-
cartilage of the wrist-joint.
Styloid Processes (9),— projecting from the head in-
ternally and posteriorly, its apex gives attachment
to the ulno carpal ligament and a depression at its
root to the fibro-cartilage of the joint.
Groove, — for the tendon of the extensor carpi ulnaris
The Radius lies externally to the ulna when the fore-
arm is in supination; it is prismatic in form with the base below where it
articulates with the carpus. The bone is curved outward and is shorter
than the ulna, by the length of the olecranon. It presents the follow-
ing points from above downward, viz. —
Head (n), — cylindrical and cup-shaped, articulating with the capitellum
of the humerus, and the lesser sigmoid cavity or radial notch, of the
ulna, and playing within the orbicular ligament.
Neck (12), — the constricted part below the head.
Bicipital or Radial Tuberosity (13), — rough behind lor the inser-
O HUMAN ANATOMY
tion of the biceps, and smooth in front where it is covered by a
bursa.
Shaft (10), — •prismoid in form, presents a sharp border internally for the
attachment of the interosseous membrane; the Nutrient Foramen is on
its anterior surface. It gives attachment to 8 of the 1 2 muscles of the
forearm.
Ridge (14), — for the insertion of the pronator radii teres muscle.
Ulnar Notch or Sigmoid Cavity, — at the ulnar side of the carpal end (15),
is shallow, and articulates with the head of the ulna.
Articular Surface, — is divided by a ridge into 2 facets for articulation
with the semilunar and scaphoid bones of the carpus.
Styloid Process (16), — gives attachment by its apex to the radio-carpal
ligament, and by its base to the supinator longus muscle.
Grooves, — on the posterior surface of the lower extremity, for the
tendons of the 8 extensor muscles of the thumb, and those of the radial
side of the wrist, and fingers.
THE HAND
The Bones of the Hand are divided into the carpus 8, the metacarpus 5,
and the phalanges 14. Total, 27 bones.
FIG. 30.
Bones of the Carpus. The 8 bones are.
placed in 2 rows, one row in front of the
other, with 4 bones in each row, as follows,
— the right hand being in supination, nam-
ing from without inward, viz. —
i5/ or Proximal Row, — Scaphoid, or
Navicular (s), Semilunar, or Os
Lunatum (L), Cuneiform, or Os Tri-
quetrum (c), Pisiform (p).
2d, or Distal Row, — Trapezium, or
Greater Multangular (T), Trapezoid or
Lesser Multangular (T), Os magnum,
or Os Capitatum (M), Unciform, or
Os Hamatum (u).
Articulations in the Carpus are 34, as follows: — the number after each
bone representing the number of its articulations, viz. —
Scaphoid; 5. Semilunar, 5. Cuneiform 3. Pisiform, i.
Trapezium, 4. Trapezoid, 4. Os-magnum, 7. Unciform, 5.
CARPAL AND METACARPAL BONES 5!
Peculiarities of the Carpal Bones. The first three enter into the forma-
tion of the wrist-joint; the pisiform does not, but is wholly without it, and
may be considered a mere appendage of the carpus. When the hand is in
pronation —
The Scaphoid (navicular), or boat-shaped bone (S) — has a tuberosity
on, its outer side, its largest facet is uppermost and articulates with
the lower end of the radius (R). A transverse groove crosses its
posterior surface and serves for the attachment of ligaments.
The Semilunar Bone (os lunatum) (L) — has a crescentic facet externally,
and a convex facet superiorly, where it articulates with the radius.
The Cuneiform Bone (os triquetrum) (C) — is wedge-shaped, its convex
surface above, articulating with the interarticular nbro-cartilage of
the wrist (F). It has an oval facet anteriorly for articulation with
the pisiform.
The Pisiform Bone (os pisiforme) (P) — is the smallest, and has but one
facet, which lies posteriorly when the bone is in position.
The Trapezium (os multangulum majus) (T) — has a deep groove for the
tendon of the flexor carpi radialis, and a saddle-shaped facet, infe-
riorly for the base of the ist metacarpal.
The Trapezoid (os multangulum minus) (T) — is small and quadrilateral,
bent on itself, with a saddle-shaped facet looking downward, for the
base of the 2d metacarpal bone.
The Os-magnum (os capitatum) (M) — has a head looking upward, a
neck, and a body; is the largest bone of the carpus, and has 3 facets
on the inferior surface for articulation with the 2d, 3d, and 4th
metacarpal bones.
The Unciform Bone (os hamatum) (U) — is wedge-shaped, with a con-
cavity which lies to the outer side, and the unciform process, long and
curved, projecting from its palmar surface.
OSSA METACARPALIA
The Metacarpus consists of the 5 metacarpal bones which are placed
between the carpus and the phalanges. They are long bones, and each
has a head, shaft and base. Their heads articulate with the respective
phalanges.
The Thumb or ist Metacarpal Bone (i), — articulates with the trapezium,
(greater multangular}, is shorter than the others by one-third, and
its base has but i articular facet.
The Index or id Metacarpal Bone (2), — articulates with 3 bones of the
carpus, the trapezium, (gr"ater multangular} trapezoid (lesser mult-
52 HUMAN ANATOMY
angular) and os-magnum (capitate) ; its base is large, and has 4 articu-
lar facets.
The Middle or 3^ Metacar pal Bone (3), — articulates with i bone of the
carpus, the os-magnum (capitate} ; its base has a projecting process on
the radial side, and 2 small facets on the opposite side.
The Ring or tfh Metacar pal Bone (4), — articulates with 2 bones of the
carpus and with the adjacent metacarpal bones; its base is small and
has 2 circular facets i on each side.
The Little or $th Metacarpal Bone (5), — articulates with i carpal bone,
the unciform (hamate}, its base has i lateral articular facet.
The Phalanges DigitorumManus or finger-bones, are 14 in number, 3 to
each finger, and 2 to the thumb. They are long bones, and each has a
base, a shaft, and a digital extremity. The Bases of the first row articu-
late with the heads of the metacarpal bones. The Digital Extremities of
the first and second rows have each 2 small lateral condyles, while in the
terminal row they are rough, for the attachment of the sensitive pulp of
the fingers.
THE THIGH
The Femur or thigh-bone, is the longest, largest and strongest bone in
the body, and is nearly cylindrical in the greater part of its extent. In
the vertical position of the skeleton it forms one side of a triangle, of which
the base is the breadth of the pelvis, and the apex at the knee-joints.
The base of this triangle is longest in the female, and consequently that
sex is usually knock-kneed. The —
Head (5), — articulates with the acetabulum, forms about two-fifths of
a sphere, and has an oval depression (6) below its centre for the attach-
ment of the ligamentum teres.
Neck (7), — connects the head with the shaft, is pyramidal and flattened;
its obliquity varies with age, being less before puberty, about 120
to 125 degrees in the adult, and nearly horizontal to the shaft in old
or debilitated subjects, the cancellous bone forming the neck is
condensed centrally into a hard core known as the calcar femorale.
Great Trochanter (8), — a broad, rough, quadrilateral process directed
outward and backward from the summit of the shaft to within three-
fourths of an inch of the level of the head. On its outer surface the
tendon of the gluteus maximus plays over a bursa. It gives insertion
to the obturator internus, two gemelli, pyriformis, and gluteus mini-
mus and medius muscles.
THE FEMUR
53
Trochanteric or Digital Fossa (9), — on the inner or medial surface of
the great trochanter, gives insertion to the obturator externus muscle.
Lesser Trochanter (10), — at the inferior root of the neck posteriorly,
is small and conical, and affords insertion to the tendon of the psoas
magnus muscle, the tendon of the iliacus
being inserted immediately below it.
Inter-lrochanteric Line, — at the base of the neck
in front runs from one trochanter to the
other, to it is attached the front part of the
capsule of the hip-joint.
Inter-trochanteric Ridge or Crest, — at the base of
the neck behind, to its middle portion is
attached the quadratus femoris muscle.
Shaft, — is slightly curved forward, broad and
cylindrical at each end, and narrow and
triangular in the centre. Its nutrient foramen
perforates its posterior surface below the
centre, and is directed toward the hip. From
its anterior surface arise the crureus or vastus-
intermedius, and subcrureus or articularis
genu muscles.
Linea Aspera (i),-— a crest lying along the central
third of the shaft posteriorly; bifurcating
above (2) towards each trochanter, also below
(4) towards the 2 condyles. To its outer lip
is attached the vastus externus, or lateralis,
to its inner lip, the vastus internus, or medi-
an's; and between them, the pectineus, ad-
ductor brevis, and gluteus maximus above the
short head of the biceps below, and the
adductors longus and magnus along the
greater portion of the space.
Groove, — crossing the internal condylar ridge,
lodges the femoral artery.
Popliteal Space, — triangular and smooth, lying between the condylar
ridges, for the popliteal artery.
Lateral or External Condyle (n), — broader and shorter than the internal,
so as to form a horizontal articulation, the bone being inclined towards
the median line. It gives attachment to the external lateral liga-
ment, the popliteus, and the lateral head of the gastrocnemius.
Medial or Internal Condyle (12), — the longer by half an inch; it gives
54 HUMAN ANATOMY
attachment to the internal lateral ligament and medial head of the
gastrocnemius muscle.
Intercondylar Notch (13), — lodges the crucial, or cruciate, ligaments.
In front the condyles are continuous with each other, forming a
concave depression or trochlea for the patella.
Lateral Epicondyle or Outer Tuberosity (14), — on the external condyle,
for the attachment of the external lateral ligament.
Groove, — below the outer tuberosity, for the tendon of the popliteus
muscle, terminating in a depression whence the muscle takes its origin.
Medial Epicondyle or Inner Tuberosity (15), — on the internal condyle,
for the attachment of the internal lateral ligament.
Adductor Tubercle, — above the inner tuberosity, for the insertion of the
tendon of the adductor magnus muscle.
Depression, — behind the tubercle, for the tendon of the inner head of
the gastrocnemius.
THE PATELLA
The Patella is flat and triangularly ovoidal with its apex directed
downward.
Subcutaneous Surface, — convex, presenting longitudinal ridges and many
nutrient foramina.
Apex,— very rough on its deep surface for attachment of ligamentum
patellae. Articular surface presents a longitudinal articular ridge
flanked by concave facets of which the lateral one is the larger. The
medial facet often presents a "third facet" along its medial border.
THE LEG
The skeleton of the leg consists of 3 bones, the tibia, the fibula, and the
patella, the latter being a large, sesamoid bone placed in front of the knee.
The Tibia, or shin-bone, ranks next to the femur in respect to size and
length. Its form is prismoidal, the upper extremity being much larger
than the lower. It presents the following points: —
Head, — expands into two tuberosities, internal (2) and external (3)
which articulate with the condyles of the femur. In spite of their
being receiving cavities, the tuberosities of the tibia are sometimes
called condyles.
Spine or Eminentia Intercondyloidea (4), — projects vertically between
the 2 articular surfaces, is bifid, affording attachment to the semilunar
fibro-cartilages (semilunar menisci), and by depressions in front and
behind its base to the crucial ligaments of the joint.
Extensor Tuberosity (5), — on the head, anteriorly between the tuber-
osities, for the insertion of the ligamentum patellae.
THE TIBIA AND FIBULA
55
Popliteal Notch or Posterior Intercondylar Fossa, — posteriorly between
the tuberosities, affords attachment to the posterior crucial ligament.
Groove, — on the inner tuberosity (2) posteriorly, for the insertion of the
tendon of the semi-membranosus muscle.
Facet, — on the outer tuberosity (3) posteriorly and looking downward,
for articulation with the head of the fibula.
Soleus Ridge or Popliteal Line, — obliquely across the
upper part of the shaft posteriorly, affords attach-
ment to the soleus.
Nutrient Canal, — the largest in the skeleton, opens
just below the popliteal line, and is directed down-
ward.
Shaft (i), — has 3 sharp ridges, — i in front, the Crest
(6) or Shin, and i on either side, to the external of
which is attached the interosseous membrane.
Lower Extremity (7), — is smaller than the upper,
grooved posteriorly for the tendon of the flexor
longus pollicis; externally has a rough triangular
depression for articulation with the fibula, and for
the attachment of the inferior interosseous liga-
ment. Its inferior surface is concave and smooth
for articulation with the upper surface of the astrag-
alus or talus.
Internal Malleolus (8), — projects downward from the
internal side of the lower extremity. It articulates
with the astragalus (talus) , is grooved posteriorly for
the tendons of the tibialis posticus and flexor longus
digitorum muscles, and affords attachment to the
internal lateral ligament.
The Fibula, is a long slender bone, placed nearly parallel
with the tibia on the outer side of the leg. It is also called the Peroneus,
or peroneal bone.
Head (10), — articulates with the external tuberosity (lateral condyle)
of the tibia by a flat facet. Externally, it has a prominence for the
attachment of the long external lateral ligament of the knee-joint.
Styloid Process, or Apex Capituli, — projects upward from the head
posteriorly, and gives insertion to the tendon of the biceps muscle,
and the short external lateral ligament of the knee-joint.
Shaft (9), — is twisted about ninety degrees on its long axis. It is
»ften very irregular and may present numerous longitudinal ridges
56 HUMAN ANATOMY
which seem to give it many surfaces. However, it always presents
certain characteristics which are constant. On the outer or lateral
surface at its distal end, it presents a long smooth subcutaneous
triangle. The ridge running from the apex of this triangle to the
front of the head of the bone, is the anterior border or crest. The
very first ridge internal (medial) to anterior border, no matter how
near or distant it may be, is the interosseous border or crest. This
border runs upward from the rough interosseous triangle to the
inner (medial) side of the head. It may, for part of its length, join
the anterior border. Running spirally upward from the groove for
the peroneal tendons to the styloid process (apex capituli), is the
posterior border (lateral crest}. The interval between the anterior
border and the interosseous border, however narrow it may be, is the
extensor surface (anterior part of the medial surface), from above
downward it gives attachment to extensor digitorum communis,
extensor hallucis longus, and peroneus tertius. The interval be-
tween the anterior border and the posterior border (lateral crest) is
the peroneal surface (lateral surface). The upper third of this
surface gives attachment to the peroneus longus, the middle third,
to the peroneus brevis; lower third is free. The entire interval be-
tween the posterior border and the interosseous border is the flexor
surface. Running from the back of the head downward and forward
and finally joining the interosseous border, is the oblique ridge
(not border) also called the medial crest. This oblique ridge
divides the flexor surface into two portions; one which is close to
the interosseous border (posterior portion of the medial surface) for
the tibialis posticus; the remainder of the flexor surface which is
distant from the interosseous ridge (posterior surface), from above
downward gives attachment to the soleus and flexor hallucis longus.
Nutrient Canal, — opens about the centre of the shaft posteriorly, its
canal running downwards.
External Malleolus (n), — is the lower extremity of the bone. It is
larger and longer than the internal, articulates with the astragalus by
a triangular facet, and is grooved posteriorly for the tendons of the
peroneus longus and peroneus brevis muscles. Its edge affords attach-
ment to the external lateral ligaments of the ankle-joint.
THE FOOT
The Bones of the Foot are divided into those of the tarsus 7, metatarsus
5, and phalanges 14. Total, 26 bones.
THE BONES OF THE FOOT
FIG. 33.
Bones of the Tarsus are placed in 2 rows side by side, 2 bones in the
external row, 5 in the internal, as follows, viz. —
Internally, — Astragalus or Talus (5). Scaphoid or Navicular (8). 3
Cuneiform (10, n, 12).
Externally, — Os calcis (i), or Calcaneum. Cuboid (6).
(The illustration, Fig. 33, shows the plantar
surface of the skeleton of the foot.)
Articulations in the Tarsus are 28 in num-
ber, each bone articulating with 4 others,
except the os calcis (calcaneus), which articu-
lates with 2, and the external (third) cunei-
form with 6 bones.
Peculiarities of the Tarsal Bones. They
may be divided transversely at the astrag-
al o-scaphoid-calcaneo-cuboid articulation ,
the site of Chopart's operation. The —
Astragalus or Talus (5), — has a rounded
head, a convex surface on which is a
broad articular facet, and on its inferior
surface a deep groove between 2 articu-
lar facets.
Os Calcis or Calcaneus (i), — is a large bone,
having on its upper surface a deep groove
for the interosseous ligament, between
2 articular surfaces; anteriorly a large
irregular portion, the head; and poste-
riorly an elongated portion forming the
Heel (2). On its internal surface is a
projection, the Sustentaculum Tali, which supports the internal
articulating surface; below which process the bone is deeply grooved
for the plantar vessels and nerves and the flexor tendons. To the os
calcis are attached 8 muscles and the plantar fascia.
Navicular or Scaphoid Bone (8), — is boat-shaped, has 3 facets anteriorly
for the cuneiform bones, a concave surface posteriorly for the astrag-
alus, and a facet externally for the cuboid bone. A tubercle (9) is
situated on the lower surface internally, for the insertion of the tibialis
posticus muscle.
Cuboid Bone (6), — has 3 articular surfaces, and a groove inferiorly for
the tendon of the peroneus longus.
Internal or First Cuneiform Bone (10), the largest of the 3, has a tubercle
EJAL.9,
58 HUMAN ANATOMY
on its plantar surface for the insertion of parts of the tendons of the
tibialis anticus and tibialis posticus muscles.
Middle or Second Cuneiform Bone (n), — is small and wedge-shaped with
the narrow end downward. Its anterior surface is considerably
behind the line of the tarso-metatarsal articulation, thus forming a
recess into which the base of the second metatarsal bone fits.
External or Third Cuneiform Bone (12), — is also wedge-shaped, but
longer than the middle one; and affords origin to i muscle, the flexor
brevis pollicis.
The Metatarsus consists of 5 metatarsal bones, which are long bones,
having each a shaft and two extremities. Their bases articulate with the
tarsal bones and with each other; their heads with the first row of phalanges.
ist Metatarsal (i3),: — is large but shorter than^the others, and forms the
inner border of the foot, articulating with the internal cuneiform.
The head is large and has two grooved facets on its plantar surface,
over which glide 2 sesamoid bones (19).
2d Metatarsal (14), — is the longest; its base has 3 facets for articulation
with the 3 cuneiform bones in the recess formed by the shortness of
the middle or second cuneiform.
•$d Metatarsal (15), — has 2 facets on the inner side of its base, besides
the facets for the internal cuneiform and the 4th metatarsal bone.
4th Metatarsal (16), — articulates with the cuboid bone, and also with the
internal or first cuneiform.
^th Metatarsal (17), — articulates obliquely with the cuboid bone, and
has a tubercular projection (18) on the outer surface of its base, which
forms the guide in Key's operation.
The Phalanges of the Foot number 14 as in the hand, the great toe
having two (20, 21), the other toes three each. They are long bones,
each having a base, a shaft, and an anterior extremity. They are convex
above, concave below, and articulate by the bases of the first row with the
bones of the metatarsus. The anterior extremities of the distal phalanges
(21, 23) are expanded into surfaces for the support of the nails and pulp
of the toes.
THE ARTICULATIONS
An Articulation or Joint is a connection between two bones of the skele-
ton, and has entering into its formation the following-named structures —
bone, cartilage, fibro-cartilage, ligament and synovial membrane.
ARTICULATIONS
Articulations are divided into three classes, — Synarthrosu, immovable
joint; Amphiarthrosis, mixed articulation, having limited motion; and
Diarthrosis, movable joint, having free motion.
Synarthroses are subdivided into — Sutura, formed by processes and in-
dentations; Schindy'lesis, by a plate of bone entering into a fissure of an-
other; and Gompho'sis, by a conical process into a socket. The Sutura are
again subdivided into — S. dentata, having tooth-like processes; S. serrata,
with serrated edges; S. limbosa, having beveled margins and dentated proc-
esses; S. squamosa, with thin beveled margins overlapping each other; S.
harmonia, contiguous rough surfaces opposed to each other. The first 3
are also named Sutura Vera (true sutures) having indented borders; the
last 2 Sutura Notha (false sutures) being formed by rough surfaces.
Amphiarthroses are subdivided into — Symphysis, connected by fibro-
cartilage and not separated by synovial membrane; Syndesmosis, united
by an interosseous ligament.
Diarthroses are subdivided into — Ginglymus, hinge-joint; Trochoides,
pivot-joint, formed by a ring surrounding a pivot; Condyloid, by an ovoid
head in an elliptical cavity; Reciprocal Reception, saddle-joint, by surfaces
inversely convex and concave; Enarthrosis, ball-and-socket joint; Arthrodia,
gliding joint.
Examples of each of the above-named articulations, as follows: —
Synarthrosis, — joints of the cranium and face, except the lower jaw.
Sutura Dentata, — the inter-parietal suture.
Sutura Serrata, — the inter-frontal suture.
Sutura Limbosa, — the fronto-parietal suture.
Sutura Squamosa, — the temporo-parietal suture.
Sutura Harmonia, — the intermaxillary suture.
Schindylesis, — rostrum of sphenoid with the vomer.
Gomphosis, — the teeth in their alveoli.
Amphiarthrosis, — the joints between the bodies of the vertebras (sym-
physes), the inferior tibio-fibular articulation (syndesmosis).
Diarthrosis, movable joint, as follows: —
— -Ginglymus, — inter-pharyngeal joints and the elbow-joint.
——Trochoides, — superior radio-ulnar, atlanto-axial joint. (Articulatio
Atlanto-epistrophica.)
Condyloid, — the wrist-joint.
Reciprocal Reception, — the carpo-metacarpal joint of the thumb.
Enarthrosis, — the hip- and shoulder-joints.
Arthrodia, — the carpal and tarsal articulations.
OO HUMAN ANATOMY
Varieties of Motion in Joints are 4 in number, viz. — gliding, angular
movement (including adduction, abduction, flexion and extension),
circumduction and rotation. These movements are often more or less
combined in the various joints.
Structures entering into the formation of Joints are 5, viz., — the
articular lamella of bone, cartilage, fibro-cartilage, ligaments and synovial
membrane.
Articular Lamella of Bone — differs from ordinary bone tissue in being
more dense, containing no Haversian canals nor canaliculi, and having
larger lacunae.
Cartilage, — a non-vascular structure, is divisible into temporary and
permanent varieties. The first forms the original frame-work of the
skeleton, and becomes ossified. Permanent cartilage is not prone
to ossification, and is divided into 4 groups, — Articular, covering the
ends of bones in joints; Inter articular, between the bones in a joint;
Costal, forming part of the skeleton; and Membraniform. According
to its minute structure, cartilage is divided into Hyaline Cartilage,
White Fibro-cartilage and Yellow or Elastic Fibro-cartilage.
Fibro-cartilages, — in joints and osseous grooves are of the white variety
and may be arranged in 4 groups, the — Inter articular (menisci) , separat-
ing the bones of a joint; Connecting, binding bones together; Circum-
ferential, deepening cavities; Stratiform, lining grooves.
Ligaments — are bands of white fibrous tissue, except the ligamenta
subflava and the ligamentum nuchse, which consist entirely of yellow
elastic tissue.
Synovial Membranes — secrete the synovia, a viscid, glairy fluid, and
resemble the serous membranes in structure. They are Articular,
lubricating joints; Bursal, forming closed sacs (bursae), interposed
between surfaces which move upon each other; Vaginal, ensheathing
tendons.
ARTICULATIONS OF THE TRUNK
The Temporo-mandibular Articulation is a ginglymo-arthrodial joint
between the condyle of the lower jaw and the anterior part of the glenoid
cavity of the temporal bone. It has 2 synovial membranes with an
interarticular fibro-cartilage between them, and 4 ligaments, viz. —
External Lateral, — from the tubercle of the zygoma to the outer side of
the neck of the condyle of the lower jaw.
Spheno-mandibular or Internal Lateral (d), — from the alar spine of the
ARTICULATIONS OF THE TRUNK
6l
PIG. 34-
sphenoid to the mandibular spine or lingula on the margin of the
dental foramen.
Stylo-mandibular (/), — from the styloid process of the temporal bone tc
the angle and posterior border of the ramus of the lower jaw.
Capsular (c), — from the edge of the glenoid cavity and the eminentia
articularis to the neck of the condyle of the lower jaw.
Its Nerves are derived from the auriculo-
temporal and masseteric branches of the
mandibular. Arteries from the temporal
branch of the external carotid.
The Vertebral Articulations are formed by
the adjacent surfaces of the bodies of the
vertebrae and their processes, and are con-
nected by the following ligaments, etc. —
' Anterior Common Ligament (i), — along the
fronts of the bodies.
f\\ Posterior Common Ligament, — along the
backs of the bodies.
2J Ligamenta Subflava, — connect the laminae of adjacent vertebrae.
If I Capsular (4), — surround the articular processes and are lined by
synovial membrane.
^j
Supra-spinous and nter-spinous,
FIG. 35.
— connect the spinous processes.
In the cervical region they form
what is called the Ligamentum
Nuchae.
Inter-transverse (3), — connect the
transverse processes.
Intervertebral Substance, — in lentic-
ular disks between the bodies of
the vertebrae, from the axis to
the sacrum.
The Atlanto-axial Articulation is
a double arthrodia or gliding joint
between the articular processes and
a pivot articulation between the atlas and the odontoid process. It
has 6 ligaments and 4 synovial membranes, as follows: —
Anterior 2, and Posterior i, Atlanto-axial, — -continuations of the anterior
and posterior common spinal ligaments.
Capsular 2, — surrounding the articular surfaces, each lined by a synoviai
membrane.
62
HUMAN ANATOMY
PIG. 36.
Transverse Ligament, — divides the spinal foramen of the atlas into two
portions, stretching across between the tubercles on the inner sides of
the articular processes. It holds the odontoid process in place, having
a synovial membrane interposed. Another synovial membrane is
situated between the process and the anterior arch. The transverse
ligament sends two vertical slips, one upward, the other downward,
from which it is often named the Cruciform Ligament.
The Occipito-atlantal Articulation is a double condyloid formed by the
condyles of the occipital bone with the
superior articular surfaces of the atlas,
and has 6 ligaments, viz. —
Anterior Occipito-atlantal (a), — from
the anterior margin of the fora-
men magnum to the anterior arch
of the atlas.
Posterior Occipito-atlantal, — from the
posterior margin of the foramen
magnum to the posterior arch of
the atlas. It is perforated by the
vertebral and suboccipital nerves.
Lateral 2, — from the jugular processes of the occipital bone to the bases
of the transverse processes of the atlas.
Capsular 2 (d), — around the articular surfaces, lined by synovial mem-
brane.
The Occipito-axial Articulation is formed by the occipital bone and the
odontoid process of the axis, which do not articulate with each other
strictly, but are connected with 4 ligaments, the —
Occipito-axial (i) (Membrana Tectoria), — a continuation of the posterior
common spinal ligament to the basilar process of the occipital bone.
Lateral Occipito-odontoid (5) (Check Ligaments} 2, — from the head of
the odontoid process to the inner sides of the occipital condyles.
Middle Odontoid (Ligamentum Suspensorium), — from the anterior mar-
gin of the foramen magnum to the odontoid apex.
The Costo-vertebral Articulations are each a double arthrodia between
the head of the rib and the bodies of 2 adjacent vertebrae, except in the
ist, roth, nth, and i2th ribs, which are single, as they articulate with
but i vertebra each. Their ligaments are 3, viz. —
Anterior Costo-central (2), or Stellate Ligament, — consists of 3 bundles,
which fasten the anterior part of the head of the rib to the inter-
vertebral disk and the 2 adjacent bodies.
ARTICULATIONS OF THE TRUNK 63
Intra-articiilar, — in the interior of the joint, from the crest on the head
of the rib to the intervertebral disk; on each side there is a separate
synovial membrane. In the ist, loth, nth and i2th ribs it does not
exist, hence there is but one synovial membrane.
Capsular, — surrounding the articular surfaces.
The Costo-transverse Articulations are 10 arthrodial articulations
between the tubercles of the first 10 ribs and the transverse processes of the
vertebrae next below. Their ligaments are 4, viz. — Anterior superior,
Middle (interosseous), Posterior Costo-transverse and Capsular.
The Chondro-sternal Articulations are 7 in number, i of which (the
first) is a synarthrodial and 6 are arthrodial articulations, between the
costal cartilages and the margin of the sternum. The first has no synovial
membrane, the second only has an intra-articular ligament. Each has 4
ligaments, — the Anterior and Posterior Chondro-sternal, a Capsular, and an
Inter articular. The Chondro-xiphoid Ligaments connect the xiphoid ap-
pendix to the cartilage of the 6th or 7th rib.
The Costo-chondral and Interchondral Articulations connect the
costal cartilages with the ribs and with each other respectively. With
the ribs by a depression on the end of each rib, strengthened by the
blending together of the periosteum and the perichondrium. The 6th,
7th and 8th, and sometimes the pth and loth costal cartilages articulate
with each other by their borders and each has a Capsular and an Inter-
chondral ligament, with 3 synovial membranes for the 3 articulations
between the 6th and the pth cartilages.
The Ligaments of the Sternum are an Anterior Sternal and a Posterior
Sternal ligament, with a layer of cartilage between the manubrium and the
gladiolus.
The Sacro-vertebral Articulation is similar to the other vertebral
articulations, but has 2 additional ligaments on each side, the —
Lumbo-sacral, — from the transverse process of the 5th lumbar vertebra
.to the base of the sacrum laterally and anteriorly.
Ilio-lumbar, — from the apex of the transverse processes of the 5th
lumbar vertebra to the crest of the ilium in front of the sacro-iliac
articulation.
The Sacro-coccygeal Articulation is an amphiarthrodial joint, and has
4 ligaments, viz. —
Anterior Sacro-coccygeal.
Posterior Sacro-coccygeal.
64
HUMAN ANATOMY
Two Lateral Sacro-coccygeal.
Fibro-cartilage, interposed in the joint.
The Sacro-iliac Articulation is an amphiarthrodial joint, formed by the
lateral surfaces of the sacrum and ilium. Its ligaments on each side are
the—
Anterior Sacro-iliac.
Posterior Sacro-iliac (8), — which consists of a short transverse part
(8) and a long part known as the —
Oblique Sacro-iliac.
The Sacro-ischiatic Articulation is
an amphiarthrosis between the sa-
crum and the ischium. Its liga-
ments convert the sacro-sciatic
notches into foramina, the greater
notch (5) being crossed by the lesser
ligament, the lesser notch (6) by the
greater ligament. These foramina
are described on page 13 ante.
Posterior or Great Sacro-sciatic
Ligament (1. sacrotuberosum)
(13), is the divorced tendon of
the biceps femoris muscle, it ex-
tends from the posterior inferior
spine of the ilium and the pos-
terior surface and margins of
the sacrum and coccyx (2), to
the inner margin of the tuber-
csity (4) and the ascending ramus (14) of the ischium, the latter por-
tion being known as the Falciform Ligament.
Anterior or Lesser Sacro-sciatic Ligament (1. sacrospinosum) (15), — from
the margins of the sacrum and coccyx, into the spine of the ischium
(16).
The Pubic Articulation or Symphysis Pubis, is an amphiarthrodial
joint formed by the junction of the two pubic bones with each other.
It has an interpubic disk and 4 ligaments, the —
Anterior Pubic. Posterior Pubic. Superior Pubic
Sub-pubic, forming a fibrous arch between the rami.
ARTICULATIONS OF THE UPPER EXTREMITY
The Sterno -clavicular Articulation is an arthrodial joint, formed by
the sternal end of the clavicle with the sternum and the cartilage of the ist
ARTICULATIONS OF UPPER EXTREMITY
the
FIG. 38.
rib. It has an interarticular fibro-cartilage, 2 synovial membranes and 5
ligaments, the —
Anterior Sterno-clavicidar. Inter clavicular.
Posterior Ster no-clavicular. Costo-clavicular or Rhomboid.
Capsular, — Formed by the anterior and posterior.
The Acromio-clavicular Articulation is an arthrodial joint, formed by
the outer extremity of the clavicle and the acromion process of the scapula.
It frequently has an interarticular fibro-cartilage and 2 synovial mem-
branes (usually but i is present). It has 3 ligaments, the —
Superior Acromio-clavicular(i}. Coraco-clavicular(2) j Trapezoid, externally.
Inferior Acromio-clavicular. divided into — I. Conoid, internally.
Proper Ligaments of the Scapula are 2, the Coraco-acromial, and the
Transverse, as follows: —
Coraco-acromial (3), — completes the vault partially formed by
coracoid and acromion processes over the head of the humerus.
Transverse (4), — from the base of the
coracoid process to the margin of the
suprascapular notch, converting it into
a foramen for the suprascapular nerve.
The Shoulder- joint, Articulatio Humeri,
is an enarthrodial or ball-and-socket joint,
formed by the head of the humerus and the
glenoid cavity of the scapula. It has a
Synovial Membrane which is reflected upon
the tendons of the biceps, subscapularis,
and infraspinatus muscles, and communi-
cates with bursae beneath the 2 latter ten-
dons. Its Arteries are derived from the
anterior and posterior circumflex and the
suprascapular; its Nerves from the circum-
flex (n. axillaris) and the suprascapular.
It has 3 ligaments, the —
Capsular (5), from the margin of the
glenoid cavity to the anatomical neck of the humerus; has 3 open-
ings for the reflexions of the synovial membrane over the tendons.
Coraco-humeral (6), intimately united with the capsular, extends from
the coracoid process to the greater tuberosity of the humerus.
Glenoid, a fibre-cartilaginous ring, continuous above with the tendon of
the long head of the biceps (7), and attached around the margin of
66
HUMAN ANATOMY
FIG. 39
the glenoid cavity in order to deepen the articular surface and pad
its edge.
The Elbow-joint, Articulatio Cubiti, is a ginglymus or hinge articulation,
formed by the lower end of the humerus with the greater sigmoid cavity
of the ulna (2) and the head of the radius (3). Its Synovial Membrane
is reflected over the ligaments, and includes the superior radio-ulnar
articulation. Its Arteries are derived from the anastomotica magna,
brachial, radial, ulnar, and interosseous recurrent, superior and inferior
profunda arteries. Its Nerves are branches of the ulnar, the musculo-
cutaneous and the median. It has 4 ligaments, the —
Anterior, — from the internal condyle (7) and anterior
surface of the humerus to the orbicular ligament
of the radius and the coronoid process of the ulna.
Posterior (6), — from the posterior surface of the
humerus to the olecranon process of the ulna.
External Lateral (1. collaterale radiale) (4), — from the
external condyle of the humerus passing obliquely
downward and backward behind the orbicular
ligament and the head of the radius to be attached
strongly to the ulna at a point opposite the attach-
ment of the internal lateral ligament.
Internal Lateral (1. collaterale ulnare), — from the in-
ternal condyle of the humerus (7) to the inner side
of the juncture of the coronoid and olecranon proc-
,ess£^of the ulna.
The Radio-ulnar Articulations are 3 in number, as
follows: —
SUPERIOR RADIO-ULNAR ARTICULATION — is a trochoid
or pivot-joint, formed by the head of the radius and the
lesser sigmoid cavity of the ulna. Its synovial mem-
brane is a continuation of that in the elbow-joint. It
has only one ligament, the —
Orbicular Ligament (5), consists of two distinct portions, the orbicular
and the capsular. The orbicular portion is very thick, — forms
four-fifths of a circle and surrounds the neck of the radius. It is
attached to the margins of the lesser sigmoid cavity of the ulna, and
to the external lateral ligament of the elbow-joint. The Capsular
portion is loose and thin, its fibres run from the lower margin of the
true orbicular ligament to the neck of the radius.
MIDDLE RADIO-ULNAR ARTICULATION — is formed by the shafts of the
ARTICULATIONS OF UPPER EXTREMITY 67
radius and ulna, which do not touch each other, but are connected by 2
ligaments, as follows: —
Oblique Ligament, — from the tubercle at the base of the coronoid process
of the ulna to the shaft of the radius. Its fibres run from the ulna
obliquely downward to the radius, whereas the fibers of the inter-
osseous membrane run from the radius downwards to the ulna.
Interosseous Membrane (9), — -obliquely downward from the interosseous
ridge on the radius to that on the ulna. Through the interval between
its upper border and the oblique ligament, the posterior interosseous
vessels pass.
INFERIOR RADIO-ULNAR ARTICULATION — is a pivot-joint, formed by the
head of the ulna and the sigmoid cavity of the radius. Its Synovial
Membrane (membrana sacciformis) is very loose, and sometimes com-
municates with that of the wrist-joint through an opening in the triangular
fibro-cartilage which separates the head of the ulna from the wrist-joint.
It is a capsule but is often considered as consisting of two portions which
are then called,
Anterior Radio-ulnar. Posterior Radio-ulnar.
++-
The Radio-carpal Articulation, or Wrist-joint, is a condyloid articula-
tion formed by the lower end of the radius and the triangular fibro-cartilage
with the scaphoid (os naviculare), semilunar (os lunatum), and cuneiform,
(os triquetrum) bones of the carpus. Its Arteries are the anterior and pos-
terior carpal from both the radial and ulnar, the anterior and posterior
interosseous and ascending branches from the deep palmar arch. Its
Nerves are derived from the ulnar and posterior interosseous. It is lined
by a synovial membrane, and is connected by a capsule, which is divided
into the following-named 4 ligaments, the —
External Lateral (radio-carpal). Anterior Ligament.
Internal Lateral (ulno-carpal). Posterior Ligament.
The Carpal Articulations are in 3 sets, — between the bones of the
first row, between the bones of the second row, between the 2 rows of
bones with each other.
The scaphoid, semilunar, and cuneiform bones are connected together
by Dorsal, Palmar (volar), and 2 Inter osseous Ligaments. The pisiform
bone has a separate capsular ligament and synovial membrane and 2
Palmar Ligaments connecting it with the unciform and the 5th
metacarpal.
The 4 bones of the second row are connected together by Dorsal,
Palmar and 3 Interosseous Ligaments.
68 HUMAN ANATOMY
The two rows of bones are united to each other by Dorsal, Palmar, and
2 Lateral Ligaments, the last named being continuous with the
lateral ligaments of the wrist-joint.
The Carpo-metacarpal Articulations. That of the thumb with the
trapezium is a joint of reciprocal reception, and has a Capsular Ligament
and a separate synovial membrane. The 4 inner metacarpal bones form 4
arthrodial joints with the adjacent carpal bones by 6 Dorsal, 8 Palmar, and
2 Interosseous Ligaments, irregularly disposed.
The Synovial Membranes of the Wrist are 5 in number, and are situated
as follows: — •
The First, or Membrana Sacciformis, — between the head of the ulna,
the sigmoid cavity of the radius, and the triangular interarticular
fibro-cartilage.
The Second, — between the lower end of the radius, the triangular fibro-
cartilage, and the scaphoid, semilunar, and cuneiform bones of the
carpus.
The Third, — between all the carpal bones except the pisiform and
between the bases of the inner 4 metacarpal bones; but it extends
only halfway into the 2 intervals between the 3 proximal bones of the
carpus.
The Fourth, — between the trapezium and the metacarpal bone of the
thumb.
The Fifth, — between the cuneiform and pisiform bones.
The Metacarpo-metacarpal Articulations. The 4 inner metacarpal
bones are connected together at their bases by Dorsal, Palmar, and Inter,
osseous Ligaments, and at their digital extremities by the Transverse
Ligament, a narrow fibrous band which crosses them anteriorly.
Remaining Articulations of the Hand. The metacarpo-phalangeal
are condyloid joints formed by the rounded heads of the metacarpal bones
and the shallow cavities in the extremities of the first phalanges. The
phalangeal articulations are ginglymus joints. Both sets have for each
joint an Anterior and 2 Lateral Ligaments, the former being lined each with
a synovial membrane. There are no posterior ligaments to these articula-
tions, the extensor tendons of the hand supplying their places.
ARTICULATIONS OF THE LOWER EXTREMITY
The Hip-joint is a true enarthrodial or ball-and-socket articulation,
formed by the head of the femur with the acetabulum of the os innom-
inatum. Its Synovial Membrane is extensive, investing most of the
ARTICULATIONS OF LOWER EXTREMITY 69
head and neck of the femur, the capsular, cotyloid and teres ligaments, and
the cavity of the acetabulum. Its Arteries are derived from the obturator,
sciatic, internal circumflex, and gluteal. Its Nerves are branches from the
sacral plexus, great sciatic, obturator, and accessory obturator. It has 5
ligaments as follows: the —
Capsular, — from the margin of the acetabulum and the transverse liga-
ment into the base of the neck of the femur above, the anterior inter-
trochanteric line in front, and to the middle of the neck of the bone,
behind. Superadded to and strengthening it are 3 auxiliary bands,
the fibres of which form part of the capsule, — the ilio-femoral (de-
scribed below), the ischio-femoral and the pectineo- femoral bands.
Ilio-femoral or Y -ligament, — from the anterior inferior spine of the ilium,
into the anterior inter-trochanteric line by two fasciculi. It is a
dissected portion of the capsular ligament which is very strong
anteriorly.
Ligamentum Teres, — from a depression on the head of the femur into the
margins of the cotyloid notch of the acetabulum and into the trans-
verse ligament, by two fasciculi.
Cotyloid, — a fibro-cartilaginous band surrounding the margin of the
acetabulum in order to deepen its cavity and pad its edge.
Transverse, — that part of the cotyloid ligament which crosses over the
cotyloid notch converting it into a foramen.
The Knee-joint is a complicated articulation, formed by the condyles of
the femur with the head of the tibia and the patella in front. It consists of
3 articulations in one; those between the condyles of the femur and the
tuberositis of the tibia are condylar joints, while that between the patella
and the femur is partly trochlear. Its Synomal Membrane is the largest
in the body, being reflected for 2 or 3 inches over the anterior surface of the
femur, where it is supported by the subcrureus muscle; also over its con-
dyles, the patella, semilunar cartilages, crucial ligaments, and the head of
the tibia; and it is prolonged through an opening in the capsular ligament
beneath the tendon of the popliteus. Its Arteries are derived from the
anastomotica magna, the articular branches of the popliteal, the recurrent
branches of the anterior tibial and the external circumflex of the profunda.
Its Nerves are derived from the obturator, anterior crural, external and
internal popliteal. It has 14 ligaments, of which 6 are external and 8
internal, as follows: —
Anterior, or Ligamentum Patella, — is the central portion of the common
tendon of the extensor muscles of the thigh, continued from the patella
to the tubercle of the tibia (9, Fig. 41).
HUMAN ANATOMY
Posterior, the oblique portion of which is often called Ligamentum
Winslowii (i), — from the upper margin of the intercondyloid notch
of the femur to the posterior margin of the head of the tibia, being
pIG. 4o. partly derived from the tendon of the semi-
membranosus muscle (2):
Internal Lateral (1. collateral tibiale) (5), — from
the internal condyle of the femur to the inner
tuberosity of the tibia and the internal semi-
lunar cartilage.
External Lateral 2, — from the external condyle
of the femur to the head of the fibula.
These ligaments are a Long (1. collaterale
fibulare) (6) is a divorced portion of the
peroneus longus muscle. The short external
lateral ligament (1. laterale externum breve
seu posticum) (7) is often wanting, when
present, it is behind the long external lateral
and separated from it by the tendon of the
biceps.
Capsular, — is a thin but very strong membrane, which fills in the
intervals left between the preceding ligaments and is inseparably
connected with them.
The Internal Ligaments are as follows: —
Anterior Crucial (2), — from the depression in
front of the spine of the tibia to the inner side
of the outer condyle of the femur.
Posterior Crucial (3), — from the depression behind
the spine of the tibia and the popliteal notch, to
the outer side of the inner condyle of the femur.
[To remember the positions and insertions of
these crucial ligaments, let the student cross
his index fingers over each knee in succession;
when over the right knee placing the right
finger in front, when over the left knee the
left finger in front. The positions of the fingers
will in each case correspond with those of the
respective crucial ligaments.]
Semilunar Fibro-cartilages (menisci) 2, — external (7) and internal (6),
are situated between the articular surfaces, and attached to the
depressions in front and behind the spine of the tibia. The external
one forms nearly an entire circle and gives off posteriorly a strong
PIG. 41.
ARTICULATIONS OF LOWER EXTREMITY 71
fasciculus, the ligament of Wrisberg, which is inserted into the inner
condyle of the femur.
Transverse (4), — is a connecting slip between the semilunar fibro-carti-
lages anteriorly.
Coronary or Coronal (7), — are short bands connecting the outer margins
of the fibro-cartilages with the margin of the head of the tibia.
Ligamenium Mucosum (plica synovialis patellaris) , — is a triangular fold
of the synovial membrane which at the lower border of the patella is
given off to the intercondylar notch of the femur.
Ligamenta Alaria (plicae alares), — are two fringe-like folds on the sides
of the ligamentum mucosum, and are attached to the semilunar
cartilages.
Bursa, — in the vicinity of this joint are 1 2 in number; 3 in front, 4 on the
outer side, and 5 on the inner side. Some of these are expansions
from others, some often communicate with the joint, and some are
only occasionally present. That between the patella and the skin is
the one implicated in the affection called "house-maid's knee."
The Tibio-fibular Articulations are 3 in number, as follows, viz. —
SUPERIOR TIBIO-FIBULAR ARTICULATION, in an arthrodial joint, formed
by the contiguous surfaces of the bones. It has a Synovial Membrane
which is sometimes continuous with that of the knee-joint, and 3 liga-
ments, the —
Capsular, — a membranous bag surrounding the joint and much thicker
in front than behind.
Anterior and Posterior Superior Tibio-fibular (10), — which connect the
head of the fibula with the outer tuberosity of the tibia.
MIDDLE TIBIO-FIBULAR ARTICULATION. The shafts of these bones do
not touch each other, but are connected by an Interosseous Membrane
extending between their contiguous borders, and perforated, above for the
anterior tibial vessels, below for the anterior peroneal vessels.
INFERIOR TIBIO-FIBULAR ARTICULATION, is an amphiarthrodial joint, of
the subdivision syndesmosis, and is formed by the contiguous rough
surfaces on the lower ends of these bones. Its Synovial Membrane is
derived from that of the ankle-joint, and it has 4 ligaments, the —
Inferior Interosseous, — continuous with the interosseous membrane.
Anterior and Posterior Inferior Tibio-fibular, — from the margins of the ex-
ternal malleous to the front and back of the tibia.
Transverse, — posteriorly between the 2 malleoli.
The Ankle-joint is a ginglymus or hinge-joint articulation, formed by the
lower ends of the tibia and fibula and their malleoli, with the astragalus.
72 HUMAN ANATOMY
Its Synovial Membrane is prolonged upward between the tibia and fibula for
a short distance. Its Arteries are derived from the malleolar branches of
the anterior tibial and peroneal arteries; and its Nerves from the anterior
and posterior tibial nerves. It has 4 ligaments; the —
Anterior, — connecting the anterior margins of the tibia and astragalus
or talus.
Posterior, — a very thin band of transverse fibres, connecting the posterior
margins of the tibia and astragalus.
Internal Lateral or Deltoid Ligament (1. calcaneotibiale) , — from the
internal malleolus to the 3 adjacent tarsal bones.
External Lateral, — by anterior (1. talofibulare anterius), posterior (1.
talofibulare posterius) and middle (1. calcaneofibulare) fasciculi, from
the external malleolus to the astragalus and os calcis.
The Tarsal Articulations are connected by the following-named liga-
ments, viz., the —
Calcaneo-astragaloid 3, external, internal and posterior, — connecting the
os calcis with the astragalus.
Calcaneo-cuboid 4, superior, internal, long and short, — connecting the
os calcis with the cuboid.
Calcaneo-navicular 2, superior and inferior, — connecting the os calcis
with the scaphoid or navicular bone.
Astragalo-navicular, superior, — connecting the astragalus with the
scaphoid or navicular bone.
Dorsal and Plantar Ligaments, — connecting the scaphoid with the three
cuneiform and with the cuboid, the three cuneiform with each other,
and the external cuneiform with the cuboid.
Interosseous Ligaments, — connecting the os calcis with the astragalus,
the scaphoid with the cuboid, the cuneiform bones with each other,
and the external cuneiform with the cuboid.
Nerves. All the joints of the tarsus are supplied by the anterior tibial
nerve.
The Tarso-metatarsal Articulations are 5 arthrodial joints formed by
the bases of the metatarsal bones with the adjacent bones of the tarsus, the
2d metatarsal bone articulating with all 3 cuneiform in the recess formed
by the shortness of the second cuneiform. They are united by Dorsal,
Plantar, and 3 Interosseous Ligaments. The 2d metatarsal bone has 3
dorsal ligaments, i from each cuneiform bone. The interosseous ligaments
pass from the 2d and 3d metatarsal bones to the internal and external
cuneiform.
MUSCLES AND FASCIA 73
Synovial Membranes of the Tarsus and Metatarsus are 6 in number,
and are situated as follows, viz. —
First, — between the os calcis and the astra'galus, behind the interosseous
ligament.
Second, — between the same bones in front of the interosseous ligament,
also between the astragalus and the scaphoid.
Third, — between the os calcis and the cuboid.
Fourth, — between the scaphoid and the 3 cuneiform bones, running back-
ward between the scaphoid and the cuboid, forward between the
cuneiform bones, between the external cuneiform and the cuboid,
between the middle and external cuneiform and the bases of the 2d
and 3d metatarsal, passing also between the bases of these bones and
the 4th metatarsal.
Fifth, — between the internal cuneiform and the base of the ist metatarsal
bone.
Sixth, — between the cuboid and the 4th and 5th metatarsal bones, also
running forward between their bases.
The Metatarso -metatarsal Articulations. The metatarsal bones are
connected together, except the first, at their bases by Dorsal, Plantar, and
Interosseous Ligaments. The base of the first metatarsal is not connected
with the base of the second by any ligaments, resembling the thumb in this
respect.
Remaining Articulations of the Foot. The metatarso-phalangeal
and the phalangeal articulations are similar to those in the hand, each
having a Plantar and 2 Lateral Ligaments. The extensor tendons supply
the places of the posterior ligaments.
THE MUSCLES AND FASCLE
The Muscles are the active organs of locomotion, formed of bundles ol
reddish fibres endowed with the property of shortening themselves upon
irritation, which is called muscular contractility, and chemically consisting
of 75 per cent, of water, 20 of proteids, 2 of fat, i of nitrogenous extractives
and carbohydrates, and 2 per cent, of salts, mainly potassium phosphate
and carbonate.
The Muscles are divided into 2 great classes, — Voluntary, Striped, or
Muscles of animal life, comprise those which are under the control of the
will. Involuntary, Unstriped, or Muscles of organic life, are those which
are not under the control of the will.
Voluntary Muscular Fibre consists of fasciculi enclosed in a delicate
web, the perimysium, connected together by a delicate connective tissue,
74 HUMAN ANATOMY
the endomysium, aggregated into muscular fibres, from ^Oo inch to ^oo
inch in diameter, which are enclosed in tubular sheaths, the sarcolemma,
and are marked by fine stria *passing around them transversely or some-
what obliquely. The fasciculi are formed of longitudinal fibrillae or
sarcostyles, made up of successive portions called sarcomeres, each of which
consists of a central dark part the sarcous element, and a clear layer which
is most visible when the fibre is extended (Schafer).
Involuntary Muscular Fibre is made up of spindle-shaped cells, the
contractile fibre-cells, averaging ^50 inch long and ^40 oo inch broad, col-
lected into bundles and held together by a cement-like substance. These
are aggregated into larger bundles or flattened bands, bound together by
ordinary connective tissue. Involuntary muscular fibres are found in the
walls of the alimentary canal, in the posterior wall of the trachea, in the
bronchi, the ducts of certain glands, in the ureters, bladder, urethra,
genitalia of both sexes, walls of all arteries and most veins and lymphatics,
in the iris and ciliary muscle, and in the skin.
*j£ 7 Tendons and Aponeuroses. Tendons are white, glistening cords or
' bands formed of white fibrous tissue almost entirely, have few vessels and
no nerves in the smaller ones. They serve to connect the muscles with
the structures on which they act. Aponeuroses are fibrous membranes,
of similar structure and appearance, and serve the same purpose.
Fasciae are laminae of variable thickness which invest (fascia, a bandage)
the softer structures. The superficial fascia or subcutaneous tela consists
of two layers, a superficial fatty layer (panniculus adiposus) which is
closely adherent to the true skin, covering over almost the entire body.
Except on the eyelids, penis, and scrotum, it contains much fat. The
deep layer of the superficial fascia is a fibro-muscular layer (panniculus
carnosus) it envelops the entire trunk. On the sides of the neck and upper
part of the chest it is muscular and is there called the platysma, it is also
muscular in the scrotum where it is called the dartos. The deep fascia
is of aponeurotic structure, dense, inelastic, and fibrous, ensheathing the
muscles and affording some of them attachment, it also forms the sheaths
of the vessels and nerves, and binding down the whole into a shapely mass.
Muscles are attached to the periosteum and perichondrium of bone and
cartilage, to the subcutaneous areolar tissue, and to ligaments. In the
latter case only are their tendons in direct contact with the tissue on which
they are to act.
Double-bellied Muscles are 4 in number, the — occipito-frontalis,
digastric, omo-hyoid, and the diaphragm.
MUSCLES OF THE HEAD 75
MUSCLES OF THE HEAD
CRANIAL REGION
Occipito-frontalis (a) , arises/row the external two-thirds of the superior
curved line of the occipital bone and the mastoid process of the temporal;
also from the pyramidalis nasi, corrugator supercilii, and orbicularis pal-
pebrarum fibres; and is inserted into an aponeurosis or "galea capitis,"
which covers the vertex of the skull. Action, chiefly as a muscle of facial
expression. Nerves, the frontal portion (m. frontalis) by the facial nerve,
the occipital portion (m. occipitalis) by the posterior auricular branch
of the facial.
AURICULAR REGION
I Auricularis anterior, or Attrahens Auriculam,— from the lateral cranial
aponeurosis: into the helix of the ear anteriorly. Action, to draw the
pinna forward. Nerve, temporal branch of the facial.
? Auricularis superior, or Attollens Auriculam,— -from the occipito-frontalis
aponeurosis: into thejginna of the ear superiorly. Action, to raise the
pinna. Nerve, temporal branch of the facial.
Auricularis posterior, or Retrahens Auriculam, — from the mastoid process
of the temporal bone: into the concha. Action, to retract the pinna.
Nerve, posterior auricular branch of the facial.
PALPEBRAL REGION
Orbicularis Palpebrarum (m. orbicularis oculi), — from the internal
angular process of the irontal bone, the nasal process of the superior
maxillary, and the borders of the tendo oculi; into the skin of the
eyelids, forehead, temple, and cheek, blending with the occipito-frontalis
and the corrugator supercilii. Action, to close the eyelids. Nerve,
facial; perhaps also the 3d nerve.
Corrugator Supercilii,— /row the inner end of the superciliary ridge of the
frontal bone: into the orbicularis palpebrarum. Action, to draw eye-
brow downward and inward. Nerve, facial; perhaps by the 3d nerve.
Tensor Tarsi (is classed by some as a portion (pars lacrimalis) of the
orbicularis) it arises, — from the crest of the lacrimal bone into the
tarsal cartilages by two slips. Action, to compress the puncta lacri-
malia against the globe of the eye and to compress the lacrimal sac.
Nerve, facial; perhaps also the 3d nerve.
70 HUMAN ANATOMY
ORBITAL REGION
Levator Palpebrae Superioris (9),— from the lesser wing of the sphenoid:
into the upper tarsal cartilage. Action, to lift the upper lid. Nerve,
3d cranial, or motor oculi.
The fibrous ring (annulus tendineus communis) from which arise the
recti oculi muscles, is divisible into an upper common tendon and a
lower common tendon.
Rectus Superior (5), — from the superior common tendon (ligament of
Lock wood) : into the sclerotic coat. Action, to rotate the eyeball upward.
Nerve, 3d cranial.
Rectus Inferior (4), — from the inferior common tendon (ligament of Zinn) :
•c. into the sclerotic coat. Ac-
f Itj. 42.
lion, to rotate the eyeball
downward. Nerve, 3d
cranial.
•Rectus Interims (3),— from
the inferior common ten-
don (ligament of Zinn) : into
the sclerotic coat. Action,
to rotate the eyeball in-
ward. Nerve, 3d cranial.
Rectus Externus (or lateralis)
(2), — by 2 heads, the upper
from the superior common
tendon (ligament of Lock-
wood), the lower from the
inferior common tendon
(ligament of Zinn) and a
bony process at lower margin of the sphenoidal fissure: into the scle-
rotic coat. Action, to rotate the eyeball outward. Nerve, 6th cranial,
or abducens.
Between the 2 heads of the external rectus pass the 3d, nasal branch of the
5th, and 6th cranial nerves, and the ophthalmic vein.
Obliquus Oculi Superior (6),— from about a line above the inner margin
of the optic foramen, its tendon passing through a pulley (7) near the
internal angular process of the frontal bone and thence beneath the
rectus superior: into the sclerotic coat at right angles to the insertion of
the rectus superior. Action, to rotate the eyeball on its antero-posterior
axis. Nerve, 4th cranial, or patheticus.
MUSCLES OF THE HEAD
77
FIG. 43.
Obliquus Oculi Inferior (S),—from the orbital plate of the maxilla: into
the sclerotic coat below the insertion of the external rectus and at
right angles thereto. Action, to rotate the eye on its antero-posterior
axis. Nerve, 30! cranial.
NASAL REGION
Pyramidalis Nasi (m. procerus) (c), — from the occipito-frontalis: into
the compressor naris. Action, to depress the eyebrow. Nerve, facial.
Levator Labii Superioris Alaeque Nasi (caput angulare of the m.
quadratus labii superioris) (e), — from the nasal process of the maxilla
bone: into the cartilage of the ala of the nose and into the upper lip.
Action, to elevate the upper lip, and dilate the nostril. Nerve, facial.
Dilator Naris Anterior, — from the car-
tilage of the ala: into the border of
its integument. Action, to dilate
the nostril. Nerve, facial.
Dilator Naris Posterior, — from the
nasal notch of the maxilla and the
sesamoid cartilages: into the integu-
ment a,t the margin of the nostril.
Action, to dilate the nostril. Nerve,
facial.
Compressor Nasi (m. nasalis) (</), —
from the maxilla above the incisive
fossa: into the fibro-cartilage of the
nose, being continuous with its fellow
and the pyramidalis nasi aponeu-
rosis. Action, to dilate the nostril.
Nerve, facial.
Compressor Narium Minor,—; from
the alar cartilage: into the skin at the end of the nose.
dilate the nostril. Nerve, facial.
Depressor Alae Nasi (m. depressor septi), — from the incisive fossa of
the maxilla: into the septum and ala of the nose. Action, to contract
the nostril. Nerve, facial.
MAXILLARY REGION
Levator Labii Superioris (caput infra-orbitale of the m. quadratus labii
superioris) (/), — from the lower margin of the orbit: into the upper
lip. Action, to elevate the lip. Nerve, facial.
Action, to
78 HUMAN ANATOMY
LevatorAnguliOris (m. Caninus) (o),—fromthe canine fossa of the maxilla:
into the angle of the mouth. Action, as named. Nerve, facial.
Zygomaticus Major (m. zygomaticus) (h),—from the malar bone: into
the angle of the mouth. Action, to raise the lip outward. Nerve,
facial.
Zygomaticus Minor (caput zygomaticum of the m. quadratus labii
superioris) (g), — from the malar bone anteriorly: into the angle of the
mouth, blending with the levator labii superioris. Action, to raise
the lip outward. Nerve, facial.
Musculus Quadratus Labii Superioris (B. N. A.) comprises three muscles,
each one of which is called a head or caput. The three heads are called
respectively, caput angiilare, caput infra-orbitale, and caput zygo-
maticum. The regular names for these three heads, are, in the order
given, levator labii superioris alaequae nasi, levator labii superioris,
and zygomaticus minor.
MANDIBULAR REGION
Levator Menti (m. mentalis) (m), — from the incisive fossa of the mandible
bone: into the integument of the chin. Action, as named. Nerve,
facial.
Depressor Labii Inferioris (m. quadratus labii inferioris) (I),— from the
external oblique line of the mandible: into the lower lip. Action, as
named. Nerve, facial.
Depressor Anguli Oris (m. triangularis) (»), — from the external oblique
line of the mandible: into the angle of the mouth. Action, as named.
Nerve, facial.
BUCCAL REGION
Orbicularis Oris (&), — is the sphincter of the lips, the upper portion, in
the upper lip, is attached in the mid-line to the septum of the nose
(naso-labial band), laterally it is attached to the incisor fossa of the
maxilla (superior incisive bundle). The lower portion, in the lower
lip, is attached to the mandible immediately above the mental pro-
tuberance (inferior incisive bundle). At the corner of the mouth,
the upper and lower portions decussate with each other and, deeply,
with the buccinator. Action, to close the mouth. Nerve, facial.
Buccinator (j),—from the alveolar arches of both the maxillae and mandible
and from the pterygo-mandibular ligament: into the orbicularis oris.
It forms the lateral walls of the mouth; it is pierced by the parotid duct.
MUSCLES OF THE EAR 79
Action, to compress the cheeks. Nerves (motor) facial, and (sensory)
the long buccal branch of the mandibular.
Risorius, — from the fascia over the masseter muscle: into the angle of the
mouth. Action, the laughing muscle. Nerve, facial.
TEMPORO-MANDIBULAR REGION
Masseter (i), — from the anterior two-thirds and the inner surface of the
zygoma and the malar process of the maxilla: into almost all of the outer
surface of the angle, ramus, and coronoid process of the lower jaw.
A ction, to raise the back part of the lower jaw; a muscle of mastication.
Nerve, masticator portion of mandibular.
Temporal,— from the temporal fossa and temporal fascia: into the coronoid
process of the mandible. Action, to bring the incisor teeth together;
the biting muscle. Nerve, masticator portion of mandibular.
PTERYGO-MANDIBULAR REGION
External Pterygoid, — by 2 heads, the upper, from the pterygoid ridge on
the greater wing of the sphenoid, the lower from the external pterygoid
plate, and the tuberosities of the palate and maxilla: into a depression in
front of the condyle of the mandible, and the inter-articular fibro-
cartilage. Action, to draw the jaw forward; a triturating muscle of
mastication. Nerve, masticator portion of mandibular.
Between the two heads of the external pterygoid muscle passes the internal
maxillary artery.
Internal Pterygoid,— from the pterygoid fossa of the sphenoid bone, and
the tuberosity of the palate: into the angle and inner surface of the
ramus of the jaw, as high as the dental foramen. Action, raises and
draws forward the lower jaw; a triturating muscle of mastication.
Nerve, masticator portion of mandibular.
MUSCLES OF THE EAR
The muscles of the ear include those of the pinna and those of the tym-
panum. The former are divided into two sets: Extrinsic, — the attra-
hens, attollens and retrahens auriculam (see page 75); and the Intrinsic, as
follows: —
INTRINSIC MUSCLES OF THE PINNA
Helicis Major,— from the cauda helicis: into the anterior border of the
helix. Nerve, facial.
8o HUMAN ANATOMY
Helicis Minor, — an oblique fasciculus which covers the crus helicis.
Nerve, facial.
Tragicus, — a short, vertical band of muscular fibres, on the outer surface of
the tragus. Nerve, facial.
Antitragicus, — from the antitragus: into the cauda helicis and antihelix.
Nerve, facial.
Transversus Auriculae, — on the cranial surface of the pinna, from the con-
vexity of the concha: into the prominence corresponding to the groove of
the helix. Nerve, facial.
Obliquus Auriculae. — from the upper and back part of the concha: into the
convexity immediately above it. Nerve, facial.
MUSCLES OF THE TYMPANUM
i Tensor Tympani, — from the under surface of the petrous portion of the
temporal bone, the cartilaginous Eustachian tube, and its own osseous
canal: into the handle of the malleus. Action, to draw the membrana
tympani inward and tense. Nerve, branch from otic ganglion.
Laxator Tympani, — from the base of the alar spine of the sphenoid, its ten-
don passing through the petro-tympanic fissure to be attached to the
processus gracilis (anterior processus) of the malleus. Nerve, branch
from otic ganglion (see page 301 ).
Stapedius, — from the interior of the pyramid, through the orifice at its
apex: into the neck of the stapes. Action, to rotate the base of the
stapes and compress the contents of the vestibule. Nerve, tympanic
branch of the facial.
MUSCLES OF THE NECK
SUPERIOR CERVICAL REGION
/ Platysma Myoides (panniculus carnosus), — is a muscular fascia covering
the pectoral and cervical region; it is loosely attached to the lower jaw,
the angle of the mouth, the skin, and the cellular tissue of the face.
Action, to wrinkle the skin, and depress the mouth. Nerve, facial.
Sterno-cleido-mastoid (n), — by two heads from the sternum (12) and the
clavicle (13) at its inner third: into the mastoid process of the temporal
bone, and the outer half of the superior curved line of the occipital. Ac-
tion, to depress and rotate the head. Nerves, spinal accessory, and deep
branches of the cervical plexus.
MUSCLES OF THE NECK
8l
INFRA-HYOID REGION
Sterno-hyoid (14), — from the posterior surface of the sternum and the
sternal end of the clavicle: into the body of the hyoid bone. Action, to
depress the hyoid bone. Nerve, a branch from the communicating loop
(ansa hypoglossi) between the descendens and communicans hypoglossi.
Sterno-thyroid (m. sterno-thyreoideus) (i$),—from the posterior surface
of the sternum and the cartilage of the ist rib: into the oblique line on
the ala of the thyroid cartilage. Action, to depress the thyroid (thy-
reoid) cartilage. Nerve, a branch from the communicating loop (ansa
hypoglossi) between the descendens and communicans hypoglossi.
FIG. 44-
Thyro-hyoid (m. thyreohyoideus) (16), — from the oblique line on the thy-
roid cartilage: into the body and greater cornu of the hyoid bone.
Action, to depress the larynx and the hyoid bone. Nerve, hypoglossal.
Omo-hyoid (17, i8),—from the upper border of the scapula and the trans-
verse ligament: into the body of the hyoid bone. It has a tendon in its
centre which is bound down to the clavicle and the ist rib by a loop of the
deep cervical fascia. Action, to depress the hyoid bone, and draw it
backward. Nerve, branch from the communicating loop (ansa hypo-
glossi) between the descendens and communicans hypoglossi.
6
82 HUMAN ANATOMY
SUPRA-HYOID REGION
Digastric, — by 2 bellies, the posterior one (i) from the digastric groove of
the mastoid process of the temporal bone; the anterior (2) from a fossa
on the inner surface of the mandible near its symphysis: into a cen-
. tral tendon (3) which perforates the stylo-hyoid muscle, and is bound
down to the body of the hyoid bone by an aponeurotic loop. Action, to
raise the hyoid bone and tongue. Nerves, anterior belly is supplied by a
branch of the mylo-hyoid nerve, the posterior belly by the facial nerve.
Stylo-hyoid (4),— -from thestyloid process of the temporal bone near its
base: into the body of the hyoid bone. Action, to elevate and retract
the hyoid bone. Nerve, facial. This muscle is perforated by the
digastric.
Mylo-hyoid (5), — -from the mylo-hyoid ridge of the lower jaw: into the
body of the hyoid bone and a median fibrous raphe line running from the
hyoid bone to the lower jaw. Action, elevates the hyoid bone and draws
it forward, also forms the floor of the mouth. Nerve, mylo-hyoid branch
of inferior dental (inferior alveolar).
Genio-hyoid (6), — from the inferior genial tubercles (mental spines) of
the mandible into the body of the hyoid bone. Action, same as that of
the mylo-hyoid. Nerve, hypoglossal.
LINGUAL REGION
Genio-hyo-glossus (m. genioglossus), — from the superior genial tubercles
(mental spines) of the mandible: into the body of the hyoid bone, the
side of the pharynx, and the whole length of the under surface of the
tongue, forming a fan-like muscle. Action, to retract and protrude
the tongue. Nerve, hypoglossal.
Hyo-glossus (8),— from the side of the body of the hyoid bone, and the
whole length of its greater cornu: into the side of the tongue. Action, to
draw down the side of the tongue. Nerve, hypoglossal.
Chondro-glossus, — sometimes described as a part of the hyo-glossus, from
the lesser cornu and the body of the hyoid bone: into the intrinsic mus-
cular fibres of the tongue, between the hyo-glossus and the genio-hyo-
glossus. Action, as the hyo-glossus. Nerve, hypoglossal.
Stylo-glossus (9), — from the styloid process and the stylo-mandibular liga-
ment: into the side of the tongue and the hyo-glossus muscle. Action,
to elevate and retract the tongue. Nerve, hypoglossal.
MUSCLES OF THE PHARYNX 83
Palato-glossus (m. glossopalatinus), — is one of the muscles of the tongue,
serving to draw its base upward, but is described with the muscles of
the palatal region.
Lingualis (the tongue-muscle), in 4 strata, — longitudinalis lingua
superior, composed of fibres passing forward and outward; stratum
derived principally from the extrinsic muscles, the stylo-glossus, hyo-
glossus, etc.; tr answer sus lingua and verticalis lingua, the latter
found only at the borders of the fore part of the tongue; longitudinalis
lingua inferior and fibres from the stylo-glossus. Action, to give the
tongue its various forms. Nerve, the hypoglossal is the motor nerve of
the tongue.
PHARYNGEAL REGION
Inferior Constrictor, — from the sides of the cricoid and thyroid cartilages
into the fibrous raphe of the pharynx. Action, to contract the pharyn-
geal calibre. Nerves, branches from the pharyngeal plexus, external
laryngeal, recurrent laryngeal.
Middle Constrictor,— -from the cornua of the hyoid bone and the stylo-
hyoid ligament : into the fibrous pharyngeal raphe. Action, to constrict
the pharynx. Nerves, branches from the pharyngeal plexus.
Superior Constrictor,— from the lower third of the margin of the internal
pterygoid plate and its hamular process, the contiguous part of the
palate bone, the tendon of the tensor palati, the pterygo-mandibular
ligament, part of the alveolar process of the lower jaw and the side of the
tongue: into the fibrous pharyngeal raphe and the pharyngeal spine of
the occipital bone. Action, to constrict the pharynx. Nerves, branches
from the pharyngeal plexus.
Stylo-pharyngeus (io),—from the inner side of the base of the styloid proc-
ess: into the constrictor and palato-pharyngeus muscles, and the thy-
roid cartilage. Action, to elevate the pharynx. Nerve, glosso-pharyn-
geal nerve which crosses this muscle in passing to the tongue.
PALATAL REGION
Levator Palati (m. Levator veli palatini), — from the under surface of the
apex of the petrous portion of the temporal bone and from the Eusta-
chian tube: into the posterior surface of the soft palate. Action, to
elevate the soft palate. Nerve, pharyngeal plexus.
Tensor Palati (m. tensor veli palatini),— 'from the scaphoid fossa and the
spine of the sphenoid bone and the Eustachian tube, reflected around
the hamular process: into the anterior surface of the soft palate, and the
84 HUMAN ANATOMY
horizontal portion of the palate bone. Action, to make tense the soft
palate. Nerve, a branch from the otic ganglion.
Azygos Uvulae (m. uvulae),— from the posterior nasal spine of the palate
bone, and from the soft palate: into the uvula. Action, possibly to
raise the uvula. This muscle is wrongly named, as it is a double muscle.
Nerve, pharyngeal plexus.
Palato-glossus (m. glossopalatinus) (constrictor isthmi faucium), — front
the anterior surface of the soft palate on the side of the uvula: into the
side and dorsum of the tongue. Action, to constrict the fauces. It
forms the anterior pillar of the fauces. Nerve, pharyngeal plexus of the
spinal accessory.
Palato-pharyngeus (m. pharyngopalatinus) (posterior pillar of the fauces),
— from the soft palate: into the side of the pharynx and the posterior
border of the thyroid cartilage, having joined the stylo-pharyngeus.
Action, to close the posterior nares. Nerve, pharyngeal plexus.
Salpingo-pharyngeus, — from the Eustachian tube near its orifice: into the
posterior fasciculus of the palato-pharyngeus. A ction, to raise the upper
and lateral part of the pharynx. Nerve, pharyngeal plexus.
PREVERTEBRAL REGION
Rectus Capitis Anti'cus Major (m. longus capitis),— from the anterior
tubercles of the transverse processes of the 3d, 4th, 5th, and 6th cervical
vertebrae by 4 slips: into the basilar process of the occipital bone. Action,
to flex and rotate the head. Nerves, first cervical and the loop between
it and the second. This muscle seems to be a continuation of the
scalenus anticus.
Rectus Capitis Anti'cus Minor (m. rectus capitis anterior},— from the
anterior surface of the lateral mass of the atlas, and the root of its trans-
verse process, — into the basilar process of the occipital bone. Action,
to flex and rotate the head. Nerves, as the rectus capitis anticus major.
Rectus Capitis Lateralis,— from the upper surface of the transverse process
of the atlas: into the jugular process of the occipital bone. Action, to
draw the head laterally. Nerves, as the preceding muscles.
Longus Colli, 3 portions, — the superior oblique, from the anterior tubercles
of the transverse processes of the 3d, 4th, and 5th cervical vertebrae, into a
tubercle on the anterior arch of the atlas: — inferior oblique, from the
bodies of the first 2 or 3 dorsal vertebrae, into the transverse processes of
the 5th and 6th cervical: — vertical portion, from the bodies of the lower
3 cervical and upper 3 thoracic vertebrae, to the bodies of the 2d, 3d, and
MUSCLES OF THE LARYNX AND EPIGLOTTIS 85
4th cervical. Action, to flex and slightly rotate the cervical portion of
the spine. Nerves, branches from the anterior divisions of the lower
cervical nerves.
LATERAL VERTEBRAL REGION
Scalenus Anti'cus (m. scalenus anterior) (20),— from the transverse proc-
esses of the cervical vertebrae, from the 3d to the 6th inclusive: into
the scalene tubercle on the upper surface of the ist rib. Action, to
flex the neck laterally, or to raise the ist rib. Nerves, branches from the
lower cervical. (See Fig. 44.)
Scalenus Medius (22),— -from the transverse processes of the lower 6 cer-
vical vertebrae: into the upper surface of the ist rib, behind the subcla-
vian groove. Action, same as the scalenus anticus. Nerves, branches
from the lower cervical.
Scalenus Posti'cus (m. scalenus posterior) (21), — from the posterior tu-
bercles on the transverse processes of the lower 2 or 3 cervical vertebrae:
into the outer surface of the 2d rib, behind the serratus magnus. Action,
to flex the neck laterally, or to elevate the. 2d rib. Nerves, branches
from lower cervical.
MUSCLES OF THE LARYNX AND EPIGLOTTIS
MUSCLES OF THE VOCAL CORDS AND RIMA GLOTTIDIS
Crico-thyroid (m. cricothyreoideus),— 'from the front and side of thecricoid
cartilage (6) : into the lower and inner borders of the thyroid cartilage
(c). Action, to elongate and make tense the
vocal cords. Nerve, external laryngeal.
Crico-arytenoideus Posticus (posterior),—- from
the cricoid cartilage posteriorly : into the outer
angle of the base of the arytenoid cartilage.
Action, to rotate the arytenoid cartilages out-
ward and open the glottis, while keeping the
vocal cords tense. Nerve, recurrent laryngeal.
A small fasciculus, called Kerato-cricoideus, is
sometimes found below the arytenoideus, ex-
tending from the cricoid cartilage to the inferior
cornu of the thyroid. It occurs once in 5 cases,
usually on one side only, but occasionally on
both, and acts to fix the lower horn of the thyroid
cartilage backward and downward. [Sir Wm.
Turner.]
86 HUMAN ANATOMY
Crico-arytenoideus Lateralis (d)—from the upper border of the cricoid
cartilage laterally: into the outer angle of the base of the arytenoid
cartilage. Action, to rotate the arytenoid cartilages inward and close
the glottis. Nerve, recurrent laryngeal.
Arytenoideus, — from the posterior surface and outer border of one ary-
tenoid cartilage: into the corresponding parts of the opposite cartilage.
A single muscle which fills the posterior concave surface of these carti-
lages. Action, by approximating the arytenoids, to close the back part
of the glottis. Nerves, internal and recurrent laryngeal.
A fairly constant muscle, the Arytenoideus rectus, is found beneath the ary-
tenoideus, extending from the posterior surface of the arytenoid carti-
lage to the posterior surface of the cartilage of Santorini [Luschka].
•v Thyro-arytenoideus (e), — from the receding angle of the thyroid cartilage
and the crico-thyroid membrane: into the base and anterior surface of
the arytenoid cartilage. Action, to shorten and relax the vocal cords by
approximating the cartilages. Nerve, recurrent laryngeal.
MUSCLES or THE EPIGLOTTIS
Thyro-epiglottideus, — from the inner surface of the thyroid cartilage:
into the margin of the epiglottis and the aryteno-epiglottidean fold.
Action, a depressor of the epiglottis. Nerve, recurrent laryngeal.
Aryteno-epiglottideus Superior,— from the apex of the arytenoid carti-
lage : into the aryteno-epiglottidean folds. A ction, to constrict the supe-
rior laryngeal aperture. Nerve, recurrent laryngeal.
Aryteno-epiglottideus Inferior, — from the arytenoid cartilage anteriorly:
into the anterior surface of the epiglottis. Action, to compress the
sacculus laryngis. Nerve, recurrent laryngeal.
Another small muscle is frequently found, though rarely described in the
books, the Triticeo-glossus. It arises from the cartilaginous nodule in
the posterior thyro-hyoid ligament, and passes forward and upward to
enter the tongue along with the hyo-glossus muscle. [Bochdalek, jun.]
MUSCLES OF THE TRUNK
The muscles of the trunk may be arranged in four groups, corresponding
to the regions in which they are situated, viz. — those of the Back, the
Thorax, the Abdomen, and the Perineum.
MUSCLES OF THE BACK
The muscles of the back are in seven layers; these muscles can be
divided into two groups. First, those that are appsndicular, i.e,, those
MUSCLES OF THE BACK 87
that actuate the upper extremity, and second, those that are axial, i.e.,
those that act on the pelvis, ribs, vertebrae, and skull.
The First or Appendicular Group constitutes the first two layers of the
muscles of the back.
FIRST LAYER, —
Trapezius, and Latissimus Dorsi.
SECOND LAYER, —
Levator Anguli Scapula (m. leva tor scapulas).
Rhomboideus Minor.
Rhomboideus Major.
The, Second or Axial Group includes the remaining five layers, two that
are superficial and three that are covered in and surrounded by the
lumbo-dorsal fascia (vertebral aponeurosis).
THIRD LAYER, —
Serratus Posticus Superior (m. serratus posterior superior).
Serratus Posticus Inferior (m. serratus posterior inferior).
FOURTH LAYER, —
Splenius Capitis.
Splenius Cervicis (splenius colli).
LUMBO-DORSAL FASCIA OR VERTEBRAL APONEUROSIS
FIFTH LAYER, — consists of two distinct muscular masses, the sacro-
spinal mass and the semi-spinal mass both of which used to be in-
cluded by the term erector spinae mass.
The Sacrospinal Mass divides into three longitudinal bundles.
OUTER OR ILIO-COSTAL DIVISION, —
Ilio-costalis Lumborum (ilio-costalis or sacro-lumbalis).
Ilio-costalis Dorsi (accessorius ad ilio-costalem).
Ilio-costalis Cervicis (cervicalis ascendens).
MIDDLE OR LONGISSIMUS DIVISION, —
Longissimus Dorsi.
Longissimus Cervicis (trans versalis colli).
Longissimus Capitis (trachelo-mastoid).
INNER OR SPINAL DIVISION, —
Spinalis Dorsi.
Spinalis Cervicis (spinalis colli).
THE SEMI-SPINAL MASS, —
Semi-spinalis Dorsi.
Semi-spinalis Cervicis (semi-spinalis colli).
Semi-spinalis Capitis (complexus, the inner portion of which was
sometimes called the biventer cervicis).
88 HUMAN ANATOMY
SIXTH LAYER, —
Multifidus SpincB (m. multifidus).
Rotatores Spincz (mm. rotatores).
SEVENTH LAYER, —
Inter- spin ales.
Inter-transversalss (mm. inter-transversarii).
THE SUB-OCCIPITAL MUSCLES
Rectus Capitis Posticus Major (m. rectus capitis posterior major).
Rectus Capitis Posticus Minor (m. rectus capitis posterior minor).
Obliquus Capitis Inferior.
Obliquus Capitis Superior.
Rectus Capitis Lateralis.
FIRST LAYER
Trapezius (i),-^ro^the inner third of the superior curved line of the oc-
cipital bone, theligamentum nuchae (2), the spinous processes of the last
cervical and all the thoracic vertebrae, and the supra-spinous ligament :
into the outer third of the posterior border of the clavicle, the superior
margin of the acromion process, the whole length of the superior border
of the spine of the scapula (3), and a tubercle at its inner extremity.
Action, to draw the head backward. Nerves, spinal accessory (n.
accessorius) , cervical plexus.
Lie AMENTUM NUCHAE (2),— from the external occipital protuberance: to
the spines of the cervical vertebrae, from the 2d to the yth inclusive.
Latissimus Dorsi (4), — by an aponeurosis from the spines of the 6 lower
thoracic and the lumbar and sacral vertebrae, the supra-spinous ligament,
the crest of the ilium and the lower 3 or 4 ribs: into the bicipital groove of
the humerus. A ction, the cursor ani muscle, drawing the arm downward
and backward; or raising the lower ribs and drawing the trunk forward.
Nerve, the middle or long subscapular.
SECOND LAYER.
Levator Anguli Scapulae (m. levator scapulae) (10), — by 4 slips from the
transverse processes of the atlas and 3 upper cervical vertebrae: into the
vertebra^ border of the scapula. Action, as named. Nerves, branches
from the anterior divisions of the 3d, 4th and 5th cervical nerves.
Rhomboideus Minor (n), — from the ligamentum nuchae (2) and spines of
the 7th cervical and ist thoracic vertebrae: into the smooth surface at
the root of the spine of the scapula. Action, to draw the scapula back-
MUSCLES OF THE BACK 89
ward and upward. Nerve, branches from the anterior division of the
5th cervical.
Rhomboideus Major (12), — from the spines of the upper 4 or 5 thoracic
vertebrae and the supra-spinous ligament : into the scapula at the root of
FIG 46.
its spine and inferior angle, by a tendinous arch. Action, to draw the
scapula upward and backward. Nerve, anterior division of the 5th
cervical.
THIRD LAYER
Serratus Posti'cus Superior (m. serratus posterior superior) ,— from the
ligamentum nuchae (a), and spines of the yth cervical and upper 2 or 3
90 HUMAN ANATOMY
thoracic vertebrae: into the upper borders of the 2d, 36, 4th, and 5th
ribs, by 4 digitations. A ction, to raise these ribs in inspiration. Nerves,
external posterior branches of the upper thoracic nerves.
Serratus Posti'cus Inferior (m. serratus posterior inferior) (i6)—from
the spines of the last 2 thoracic and first 3 lumbar vertebrae: into the
lower borders of the lower 4 ribs, by 4 digitations. Action, to depress
these ribs in expiration. Nerves, external posterior branches of the
lower thoracic nerves.
FOURTH LAYER
Splenius (Capitis et Cervicis) (14), — from the lower half of the ligamentum
nuchae (2), the last cervical and upper 6 thoracic spines, and the supra-
spinous ligament: the S. capitis (13) into the mastoid process of the
temporal bone and a rough surface below the superior nuchal
line of the occipital bone, — the 5. cervicis or colli (14) into the transverse
processes of the upper 2 or 3 cervical vertebrae. Action, to draw the
head backward and the neck erect. Nerves, external posterior branches
of the cervical nerves.
Lumbo-dorsal Fascia or Vertebral Aponeurosis, — consists of three layers.
Posterior layer is the most extensive, it is attached to the spines of
sacral, lumbar, and thoracic vertebrae, its fibres pass out laterally to
blend in the lumbar region first with the middle layer and further out, at
the origin of the transversalis abdominis, it blends with the anterior
layer. The middle layer is in the interval between the sacro-spinal
mass and the quadratus lumborum. It is attached to the tips of the
transverse processes of the lumbar vertebras. The anterior layer forms
the front part of the sheath of the quadratus lumborum, it then passes
between that muscle and the psoas to become attached to the front of
the bases of the transverse processes of the lumbar vertebrae.
FIFTH LAYER. (See Fig. 47)
Sacro-spinalis or Erector Spinae (i), — from the sacro-iliac groove, and by
the lumbo-sacral tendon from the sacral, lumbar and lower 2 thoracic
spines, the iliac crest, and the posterior eminences of the sacrum : divides
into the ilio-costalis (2) and longissimus dorsi (3) muscles. Action, to
erect the spine and bend the trunk backward. Nerves, external pos-
terior branches of the lumbar nerves.
MUSCLES OF THE BACK QI
ILIO-COSTAL DIVISION
Ilio-costalis Lumbonun (sacro-lumbalis) (2), — the external portion of the
erector spinae: into the inferior borders of the angles of the lower 6 or 7
ribs. Action, as the erector spinae. Nerves, branches of the thoracic.
Ilio-costalis Dorsi or Musculus Accessorius ad Hio-costalem (2), — from
the angles of 6 lower ribs: into the angles of upper 6 ribs. Action, as the
erector spinae. Nerves, branches of the
thoracic.
Ilio-costalis Cervicis or Cervicalis Ascen-
dens (s),—from the angles of upper 4
or 5 ribs: into the transverse processes
of the 4th, 5th, and 6th cervical verte-
brae. Action, to keep the neck erect.
Nerves, branches of the cervical.
LONGISSIMUS DIVISION
Longissimus Dorsi (3). — is the middle
and largest portion of the erector spinae,
and is inserted into the transverse and
articular processes of the lumbar verte-
brae, into the tips of the transverse proc-
esses of all the thoracic vertebrae, and
into from lower 7 to n ribs between
their tubercles and angles. Action, as
the erector spinae. Nerves, branches of
the lumbar and thoracic nerves.
Longissimus Cervicis or Transversalis
Colli (6), — from the transverse processes
of the upper 6 thoracic vertebrae; into the
transverse processes of the cervical verte-
brae (9), from the 2d to the 6th inclusive.
Action, to keep the head erect. Nerves,
branches of the cervical.
Longissimus Capitis or Trachelo-mastoid
(7),— from the transverse processes of
the upper 5 or 6 thoracic vertebrae, and the articular processes of the
lower 3 or 4 cervical: into the posterior margin of the mastoid proc-
ess of the temporal bone. Action, to steady the head. Nerves,
branches of the cervical.
92 HUMAN ANATOMY
SPINAL MASS
Spinalis Dorsi,— from the last 2 thoracic and first 2 lumbar spines: into
all the remaining thoracic spines. Action, to erect the spinal column.
Nerves, branches of the thoracic.
Spinalis Cervicis or Spinalis Colli, — from the 5th, 6th and 7th cervical
spines, sometimes from the ist and 2d thoracic: into the spine of the axis
and occasionally into the spines of the next two vertebrae below. A ction,
to steady the neck. Nerves, branches of the cervical. [This muscle is
frequently absent.]
Semi -spinalis Capitis or Complexus (8), — by 7 tendons from the tips of
the transverse processes of the ;th cervical and upper 6 or 7 thoracic
vertebrae, and from the articular processes of the 4th, 5th, and 6th cer-
vical: into the inner depression between the curved (nuchal) lines of the
occipital bone. Action, to retract and rotate the head. Nerves, sub-
occipital, great occipital, and branches of the cervical nerves.
Bivenler Crevicis, — is the inner part of the Complexus, from the trans-
verse processes of upper 2 to 4 thoracic vertebrae: into the superior curved
line of the occipital bone. Action, as the complexus. Nerves, branches
of the cervical.
Semi -spinalis Dorsi (10), — from the transverse processes of the thoracic
vertebrae, from about the sth to the nth: into the last 2 cervical and
upper 4 thoracic spines. Action, to erect the spinal column. Nerves,
branches of the thoracic nerves.
Semi -spinalis Cervicis or Semi-spinalis Colli (n), — from the transverse
processes of the upper 5 or 6 thoracic vertebrae: into the 2d, 3d, 4th,
and 5th cervical spines. Action, to erect the spinal column. Nerves,
branches of the cervical.
SIXTH LAYER
Multifidus Spinae (m. multifidus) (i6],—from the back of the sacrum, pos-
terior superior spine of the ilium, posterior sacro-iliac ligaments, ar-
ticular processes of lumbar and lower 3 or 4 cervical vertebrae, and the
transverse processes of the thoracic: into the spines of the next 4 vertebrae
above. Action, to erect and rotate the spinal column. Nerves, branches
of the spinal nerves.
Rotatores Spinae (mm. rotatores),— from the transverse processes of the
thoracic vertebrae, from the 2d to the i2th inclusive: each into the
lamina of the next thoracic vertebrae above. Action, to rotate the
spinal column. Nerves, branches of the posterior thoracic.
SUBOCCIPITAL AND THORACIC MUSCLES 93
Inter-spinales, — placed in pairs between the spines of contiguous vertebrae,
6 pairs in the cervical region, 3 in the thoracic, 4 sometimes 6 in the
lumbar. Nerves, branches of the posterior spinal.
Extensor Coccygis,— from the last bone of the sacrum or first of the coccyx :
into the lower part of the coccyx, posteriorly. Action, as named.
Nerves, branches of the posterior sacral.
Inter -transversales (mm. intertransversarii) (18), — placed between the
transverse processes of contiguous vertebrae, 7 in the cervical region,
12 in the thoracic, and 4 in the lumbar. Nerves, branches of the pos-
terior spinal.
SUBOCCIPITAL MUSCLES
Rectus Capitis Posti'cus Major (m. rectus capitis posterior major) (13), —
from the spine of the axis: into the inferior curved or nuchal line of the
occipital bone and the surface below. Action, to rotate the head.
Nerves, suboccipital.
Rectus Capitis Posti'cus Minor (m. rectus capitis posterior minor) (12), —
from the tubercle on the posterior arch of the atlas: into a rough surface
between the foramen magnum and the inferior curved or nuchal line of
the occipital bone. Action, to draw the head backward. Nerves,
suboccipital.
Obliquus Capitis Inferior (15), — from the spinous process of the axis:
almost horizontally into the transverse process of the atlas. Action, to
rotate the atlas and cranium. Nerves, suboccipital.
Obliquus Capitis Superior (14), — from the transverse process of the atlas,
upward and inward into the occipital bone between the curved lines.
Action, draws the head backward. Nerves, suboccipital.
Rectus Capitis Lateralis, — from upper surface of lateral mass of atlas: into
under surface of the jugular process of the occipital bone. Action, to
flex the head laterally. Nerve, the anterior branch of the first cervical.
MUSCLES OF THE THORAX
External Intercostals, — each from the lower border of each rib: into
the upper border of the next rib below directed obliquely downward and
forward. Action, to raise and evert the ribs in inspiration. Nerves,
intercostal.
Internal Intercostals, — each from the ridge on the inner surface of each rib:
into the upper border of the rib below, directed obliquely downward and
HUMAN ANATOMY
backward. Action, at sides of thorax to depress the ribs in expiration;
anteriorly they raise the costal cartilages. Nerves, intercostals.
Infra -costales, — obliquely from inner surface of each rib: into the inner
surface of the ist, 2d, or 3d rib below. Action, muscles of inspiration.
Nerves, intercostal. [These muscles vary in number and length.]
Triangularis Sterni,— from the posterior surface of the ensiform cartilage
and lower third of the sternum, also from the sternal ends of the costal
cartilages of the lower 3 or 4 true ribs: into the lower border and inner
surfaces of the 2d, 3d, 4th, sth, and 6th costal cartilages. A ction, to draw
down the cartilages in expiration. Nerves, intercostal.
FIG. 48.
Levatores Costarum (17 Fig. 47), — each from the transverse process of the
7th cervical and upper n thoracic vertebrae: into the upper surface of
the next rib below, near its angle. Action, to raise the ribs. Nerves,
intercostal.
Diaphragm, — from the ensiform cartilage (4), inner surfaces of lower 6 or 7
ribs, ligamenta arcuata (5), and by its crura (8, 10), from the bodies of
the lumbar vertebrae: into the central or cordiform tendon (2, 3).
Action, the great muscle of respiration and expulsion. Nerves, the two
phrenic, lower intercostals and phrenic plexus of the sympathetic.
OPENINGS OF THE DIAPHRAGM, — include several small openings and 3 large
ones; the
MUSCLES OF THE ABDOMEN 95
Aortic (n), in the middle line posteriorly, and behind the diaphragm;
transmits the aorta, vena azygos major, and thoracic duct. (Esopha-
geal (12), in the muscular structure, transmits the oesophagus and pneu-
mogastric nerves. Opening for the Vena Cava (13) is the highest, and has
4 tendinous margins.
The Right Cms (8) transmits the greater and lesser splanchnic nerves of
that side: the Left Cms (10), the greater and lesser splanchnic nerves of
the left side and the vena azygos minor.
Descent of the Diaphragm. Its central tendon does not descend during
inspiration, being connected with the deep cervical fascia by the fibrous
pericardium.
MUSCLES OF THE ABDOMEN
Obliquus Abdominis Externus- or External Oblique (12), — from 8 lower
ribs by 8 fleshy digitations: into the anterior half of the outer lip of the
crest of the ilium, and by a broad aponeurosis (13) into the ensiform carti-
lage, linea alba, symphysis and spine of the pubes, and the ilio-pectineal
line. Its aponeurosis is continuous with that of the pectoralis major
above; below it forms Poupart's (1. inguinale) (14) and Gimbernat's
(1. lacunare) ligaments, and by the separation of its fibres the external
abdominal ring (15). Action, to compress the viscera, and flex the
thorax on the pelvis, and vice versa. Nerves, lower intercostal.
Obliquus Internus Abdominis or Internal Oblique (iS),—from the lumbo-
dorsal fascia, the anterior two-thirds of the middle lip of the crest of the
ilium, and the outer half of Poupart's ligament (1. inguinale) : into the
cartilages of 4 lower ribs; by its aponeurosis into the linea alba; and
leaving an arched border (20) over the spermatic cord, by the conjoined
tendon (falx aponeurotica inguinalis) (19) with the transversalis into the
pubic crest and the pectineal line. Its aponeurosis passes in front of
the rectus abdominis; the lowermost portion, from the level of the semi-
lunar fold of Douglas downward, is called the conjoined tendon because
it serves for the transversalis as well. It blends in the linea alba with
the tendons of its fellow of the opposite side and the external oblique
and transversalis of both sides. Action, same as the external oblique.
Nerves, lower intercostals, ilio-hypogastric, and sometimes from the
ilio-inguinal.
Cremaster,— from the inner part of Poupart's ligament (1. inguinale), form-
ing a series of loops along the outer side of the spermatic cord: into the
crest of the pubis and the front of the sheath of the rectus. Its origin
and insertion is precisely similar to that of the lower fibres of the internal
oblique, from which it is derived by the descent of the testicle. Action,
to raise the testicle. Nerve, the genital branch of the genito-crural.
96
HUMAN ANATOMY
Transversalis Abdominis or Transversalis,— from the outer third of
Poupart's ligament (1. inguinale), the anterior two-thirds of the inner
lip of the crest of the ilium, the cartilages of 6 lower ribs, and by its
dorsal aponeurosis (middle layer of the lumbodorsal fascia) from the
spines and transverse processes of the lumbar vertebrae: by its ventral
aponeurosis into the linea alba, and by the conjoined tendon (falx ap-
FIG. 49.
oneurotica inguinalis) (19) with the internal oblique, into the pubic crest
and the pectineal line. Its ventral aponeurosis passes behind the rectus
abdominis for about its upper three-fourths; the lower edge of this
tendon is the so-called "semilunar" fold of Douglas. Action, as the
external oblique. Nerves, as the internal oblique.
Rectus Abdominis (16), — by 2 tendons from the pubic crest and the liga-
ments covering the symphysis; into the cartilages of the 5th, 6th, an^
MUSCLES OF THE PELVIC OUTLET 97
7th ribs. It lies in a sheath formed by the aponeuroses of the internal
oblique and transversalis muscles for its upper three-fourths, and is
crossed by 3 tendinous lines, the Linece Transverse. At its outer border
is a similar line placed vertically, the Linea Semilunaris, formed by the
blending of the aponeuroses of the internal oblique and transversalis.
Action, to flex the thorax on the pelvis and vice versa, also to compress the
abdominal viscera. Nerves, lower intercostal nerves.
Pyramidalis (17), — lies in front of the rectus, but in the same sheath; arises
from the front of the pubic bone and the anterior pubic ligament:
into the linea alba, half-way to the umbilicus. Action, a tensor of the
linea alba. Nerves, lower intercostal nerves.
Quadratus Lumborum (19 Fig. 47), — from the ilio-lumbar ligament, and
the adjacent 2 inches of the crest of the ilium: into one-half of the lower
border of the last rib, and the transverse processes of the 4 upper lumbar
vertebrae. Action, to flex the thorax laterally on the pelvis and vice
versa. Nerves, anterior branches of the last thoracic and ist lumbar.
The Psoas Magnus, the Psoas Parvus and the Iliacus muscles may be con-
sidered deep muscles of the abdomen, but are described with the muscles
of the lower extremity.
MUSCLES OF THE PELVIC OUTLET
The muscles of this region are situated at the pelvic outlet in the ischio-
rectal region and the perinaeum.
MUSCLES OF THE ISCHIO-RECTAL REGION
Corrugator Cutis Ani, — A thin stratum of involuntary muscular fibre
around the anus, radiating from its orifice and serving to raise the skin
into ridges around the anal margin.
External Sphincter Ani (4),— from the tip of the coccyx and superficial
fascia: into the tendinous center of the perinaeum. Action, to close the
anus. Nerves, inferior hemorrhoidal branch of the internal pudic, also a
branch from the anterior division of the 4th sacral.
Internal Sphincter Ani, — an aggregation of the involuntary circular fibres
of the intestine, forming a muscular ring around the rectum about an
inch above the margin of the anus. Action, to occlude the anal aperture.
[A third sphincter, the Sphincter Tertius, — from the sacrum, encircling the
rectum about 4 inches above the anus, was demonstrated by Velpeau,
Nelaton and Hyrtl, but is denied by other anatomists.]
7
98 HUMAN ANATOMY
Levator Ani'(s),— -from the body and ramus of the pubis posteriorly, the
pelvic fascia and the spine of the ischium: into the tendinous centre of
the perinaeum, the sides of the rectum (and vagina), apex of the coccyx,
and a fibrous raphe extending from the coccyx to the anus. Action, to
support the lower end of the rectum and vagina and the bladder, and
assist in forming the floor of the pelvis. Nerves, branches from the 4th
sacral and pudic.
Coccygeus, — from the spine of the ischium and the lesser sacro-sciatic liga-
ment: into the margin of the coccyx and the side of the last sacral seg-
ment. Action, to support the
coccyx, and close the outlet of
the pelvis posteriorly. Nerves,
branches from the 4th and $th
sacral.
MUSCLES OF THE PERINEUM
IN THE MALE
Superficial Transversus Perinaei
(3),— from the tuberosity of
the ischium: into the central
tendon of the perinaeum. Ac-
tion, to draw tense the central
tendon. Nerve, perinea! branch
,of_the pudic.
Transversus Perinaei Profundus
(Compressor Urethrae),— from
the junction of the rami of the
pubis and ischium: into its
fellow of the opposite side after
encircling the membranous portion of the urethrae. Action, to com-
press the veins of the penis, the membranous urethra, and Cowper's
glands. Nerve, perineal branch of the pudic.
Bullo-cavernosus (Accelerator Urinae) (i), — from the central tendon of the
perinaeum and the median raphe anteriorly: the fibres spread over the
bulb, corpus spongiosum, corpus cavernosum and the dorsal vessels of
the penis. Action, to accelerate the flow of urine and erect the penis.
Nerve, perineal branch of the pudic.
ischio-cavernosus or Erector Penis (2), — from the tuberosity and ramus
of the ischium and the crus penis: into the crus penis laterally and infe-
MUSCLES OF THE UPPER EXTREMITY 99
riorly. Action, to maintain erection of the penis. Nerve, perineal branch
of the pudic.
FASCIAE OF THE PERINEUM, — are described under the title Perinaeum at
the end of the book.
MUSCLES OF THE PERINEUM IN THE FEMALE
Superficial Transversus Perinsei (3), — from the tuberosity of the ischium
internally: into the central point of the perinaeum, joining with its fellow
of the opposite side. Action, to fix the central tendinous point of the
perinaeum. Nerve, the perineal branch of the pudic.
Bulbo-cavernosus or Sphincter Vaginae, — surrounds the orifice of the va-
gina, and is analogous to the accelerator urinae of the male. Arising
from the central tendon of the perinaeum, its fibres are inserted into the
corpora cavernosa of the clitoris, a fasciculus crossing over the body of
the organ so as to compress the dorsal vein. Action, to diminish the
orifice of the vagina. Nerve, perineal branch of the pudic.
Ischio-cavernosus or Erector Clitoridis, — from the tuberosity andramus of
the ischium internally : into the crus clitoridis by an aponeurosis. A ction,
to erect the clitoris by retarding the return of its blood supply. Nerve,
perineal branch of the pudic.
Deep Transversus Perinsei or Compressor Urethras, — from the margin of
the descending ramus of the pubic bone: into its fellow in front of the
urethra and into the wall of the vagina behind the urethra. Action, as
indicated by its name. Nerve, perineal branch of the pudic.
MUSCLES OF THE UPPER EXTREMITY
MUSCLES OF THE THORACIC REGION
JL '/ Pectoralis Major (i, 2, 3), — from the sternal half of the clavicle, by an
/ / aponeurosis from the front of the sternum as low as the 6th or yth rib,
the cartilages of all the true ribs (5), and the aponeurosis of the external
oblique: the fibres converge, cross and are inserted by a flat tendon (4)
into the external bicipital ridge (crest of the great tubercle) of the hu-
merus, having crossed the bicipital groove (intertubercular sulcus).
Action, to draw the arm forward and downward; also to elevate the ribs
in forced inspiration. Nerves, anterior thoracic.
Pectoralis Minor (6),— from the 3d, 4th, and 5th ribs, and the intercostal
aponeurosis: into the coracoid process of the scapula. Action, to depress
100 HUMAN ANATOMY
the point of the shoulder, also to elevate the ribs in forced inspiration.
Nerves, anterior thoracic.
Subclavius (7), — from the cartilage of the ist rib: into a deep groove on the
under surface of the clavicle. Action, to draw the clavicle downward.
Nerve, a branch from the 5th cervical.
Serratus Magnus (m. serratus anterior), — by 9 digitations (10) from the
8 upper ribs (the 2d rib having 2) and from the intercostal aponeurosis:
into the whole length of the ventral aspect of the vertebral border of
the scapula. Action, to elevate the ribs in inspiration, also to raise the
point of the shoulder. In Lhe lower animals it is the great sling-muscle,
slinging the body between the upper extremities. Nerve, posterior
thoracic.
MUSCLES OF THE SHOULDER AND ARM
Deltoid (8),— from the outer third of the anterior and superior surfaces of
the clavicle, the outer margin and upper surface of the acromion, and the
lower border of the spine of the scapula: into a prominence on the outer
side of the shaft of the humerus, about its middle. Action, to raise the
arm. Nerve, circumflex (n. axillaris).
Subscapularis (15), — from the inner two-thirds of the subscapular fossa:
into the lesser tuberosity of the humerus. Action, to rotate the head of
the humerus inward. Nerves, subscapular.
MUSCLES OF THE UPPER EXTREMITY
101
Supraspinatus,— from the inner two-thirds of the supraspinous fossa and
the fascia covering the muscle: into the upper facet of the greater tuber-
osity of the humerus. Action, to support the shoulder- joint, and to
raise the arm. Nerve, suprascapular.
Infraspinatus,— from the inner two-thirds of the infraspinous fossa and the
covering fascia: into the middle facet on the greater tuberosity of the
humerus. Action, to rotate the humerus out-
ward. Nerve, suprascapular.
Teres Minor (14),— from the upper two-thirds of
the dorsal surface of the axillary border of the
scapula: into the lowest facet on the greater
tuberosity of the humerus, and the bone below.
Action, to rotate the humerus outward. Nerve,
circumflex (n. axillaris).
Teres Major, — from the dorsal aspect of the in-
ferior angle of the scapula: into the internal
bicipital ridge (crest of the small tubercle)
of the humerus. Action, to assist the latissimus
dorsi. Nerve, subscapular.
Coraco-brachialis (n), — from the apex of the
coracoid process (2) of the scapula: into a ridge
on the inner side of the shaft of the humerus,
about its middle. Action, elevates the humerus
forward and inward. Nerve, musculo-cuta-
neous, which perforates this muscle.
Biceps (15) (biceps flexor cubiti),— Long head (8)
from the upper margin of the glenoid cavity;
short head (12) from the apex of the coracoid
process (2), in common with the coraco-bra-
chialis : into the back of the tuberosity of the
radius, and the fascia (20) of the forearm.
Action, to flex and supinate the forearm, and
to make tense its fascia. Nerve, the musculo-
cutaneous.
Brachialis Anti'cus (m. brachialis) (17),— from
the lower half of the shaft of the humerus an-
teriorly and laterally, embracing the insertion of the deltoid (9) : into
the base of the coronoid process (19) of the ulna. Action, a flexor of
the forearm. Nerves, musculo-cutaneous and musculo-spiral (n.
radialis).
IO2 HUMAN ANATOMY
Triceps (16) (triceps extensor cubiti), — by three heads, the outer (lateral)
and inner (medial) from the posterior surface of the shaft of the humerus,
the outer above, the inner below the musculo-spiral (radial) groove;
the middle or long head from a depression (infra-glenoid tuberosity)
below the glenoid cavity of the scapula; by a common tendon into the
upper end of the olecranon process of the ulna. Action, to extend the
forearm. Nerve, musculo-spiral (n. radialis).
Sub-anconeus,— from the humerus above the olecranon fossa: into the
posterior ligament of the elbow- joint. Action, probably a tensor of the
ligament. Nerve, musculo-spiral (n. radialis).
MUSCLES OF THE FOREARM
Muscles of the Forearm, arranged in groups of 5 and 3. (Pancoast.)
ANTERIORLY, 5 flexors, 2 pronators, i tensor of palmar fascia: —
Flexor Carpi Radialis. . j Pronator Radii Teres (m. pronator
Flexor Carpi Ulnaris. \ Pronator Quadralus. teres).
Flexor Longus Pollicis. Palmaris Longus.
f Flexor Sublimis Digitorum.
1 Flexor Profundus Digitorum.
POSTERIORLY 12 muscles in 4 sets of threes: —
Brachio-radialis (Supinator Longus). Extensor Indicts.
Extensor Carpi Radialis Longior. Extensor Communis Digitorum.
Extensor Carpi Radialis Brevior. Extensor Minimi Digiti.
Extensor Ossis Metacarpi Pollicis. Extensor Carpi Ulnaris.
Extensor Brevis Pollicis. Anconeus.
Extensor Longus Pollicis. Supinator Brevis.
Pronator Radii Teres (m. pronator teres) (4), — by 2 heads, one from above
the medial or internal condyle of the humerus, the common tendon, fas-
cia, and the intermuscular septum; the other from the medial or inner
side of the coronoid process of the ulna: into a rough ridge on the radial
or outer side of the shaft of the radius, about its middle. Action, to
pronate the hand. Nerve, median, which passes between the 2 heads
of the muscle.
Flexor Carpi Radialis (5),— from the medial or internal condyle of the
humerus by "the common tendon, the fascia, and the intermuscular
septa: into the base of the metacarpal bone of the index finger. Action,
to flex the wrist. Nerve, median.
Palmaris Longus (6), — from the same origin as the flexor carpi radialis:
MUSCLES OF THE FOREARM
103
FIG. S3-
into the annular ligament (1. carpi transversum) and the palmar fascia
(9). Action, to make the palmar fascia tense. Nerve, median.
Flexor Carpi Ulnaris (8), — by 2 heads, one from the inner or medial con-
dyle of the humerus by the common tendon, the other from the inner
or medial margin of the olecranon, the upper two-thirds of the posterior
border of the ulna, and the intermuscular septum: into the pisiform
bone, the annular ligament (1. carpi transver-
sum), and the 5th metacarpal and unciform
(hamate) bones. Action, to flex the wrist.
Nerve, ulnar.
Flexor Sublimis Digitorum (Perforatus) (7), — by
3 heads, one from the medial or inner condyle
of the humerus by the common tendon, the
internal lateral or ulnar collateral ligament, and
the intermuscular septum; the second from the
inner side of the coronoid process of the ulna;
the third from the oblique line of the radius:
into the lateral margins of the second phalanges
by 4 tendons which are split for the passage of
the deep flexor tendons. Action, to flex the
second phalanges. Nerve, median.
Flexor Profundus Digitorum (Perforans),— -from
the upper three-fourths of the shaft of the ulna,
a depression on the inner side of the coronoid
process, and the interosseous membrane: into
the bases of the last phalanges, by 4 tendons
which perforate the tendons of the superficial
flexor. Action, to flex the phalanges. Nerves,
ulnar, anterior interosseous branch of the
median.
Flexor Longus Pollicis, — from the upper two-
thirds of the shaft of the radius and the in-
terosseous membrane: into the base of the last
phalanx of the thumb, which it flexes. Nerve, anterior interosseous
branch of the median.
Pronator Quadratus,— from the oblique line on the lower fourth of the
ulna, and the anterior border of the ulna: into the lower fourth of the
anterior border of the shaft of the radius. Action, to pronate the hand.
Nerve, anterior interosseous branch of the median.
104 HUMAN ANATOMY
Brachio-radialis or Supinator Longus (13), — from the upper two-thirds of
the lateral or external condylar ridge of the humerus, and the inter-
muscular septum; into the base of the styloid process of the radius.
Action, to supinate the hand. Nerve, musculo-spiral (n. radialis).
Extensor Carpi Radialis Longior (e),—from the lower third of the lateral or
external condylar ridge of the humerus, and the intermuscular septum:
into the base of the metacarpal bone of the index
FlG- 54- finger (g), on its radial side. Action, to extend
the wrist. Nerve, musculo-spiral (n. radialis).
Extensor Carpi Radialis Brevier (f),—from the
lateral or external condyle of the humerus by
the common tendon, the external lateral liga-
ment, and the intermuscular septa: into the
radial side of the base of the 3d metacarpal
bone (g). Action, to extend the wrist. Nerve,
posterior interosseous.
Extensor Communis Digitorum (h),—from the
lateral or external condyle of the humerus by
the common tendon, the deep fascia, and the
intermuscular septa: into the 2d and 3d
phalanges of all the fingers, by 3 tendons, one
of which divides into two. Action, to extend
the fingers. Nerve, posterior interosseous.
Extensor Minimi Digiti (m. extensor digiti quinti
proprius) (i),—from the common tendon and
the intermuscular septa: into the 2d and 3d
phalanges of the little finger, with the tendon
derived from the common extensor. Action, as
named. Nerve, posterior interosseous.
Extensor Carpi Ulnaris (j),—from the common
tendon, the middle third of the posterior border
of the ulna, and the deep fascia of the forearm:
into the base of the 5th metacarpal bone. Action,
to extend the wrist. Nerve, posterior interosseous.
Anconeus (£), — from the lateral or external condyle of the humerus, pos-
teriorly: into the side of the olecranon, and upper fourth of the posterior
surface of the shaft of the ulna. Action, to extend the forearm. Nerve,
the musculo-spiral (n. radialis).
MUSCLES OF THE HAND 105
Supinator Brevis (m. supinator)— from the external condyle of the hu-
merus, the external lateral and orbicular ligaments and an oblique line on
the ulna: into the inner surface of the neck of the radius, the outer edge
of its bicipital tuberosity, and the oblique line. Action, to supinate the
hand. Nerve, posterior interosseous, which pierces it.
Extensor Ossis Metacarpi Pollicis (m. abductor pollicis longus) (14), —
from the posterior surfaces of the shafts of the radius and ulna, and the
interosseous membrane: into the base of the metacarpal bone of the
thumb. Action, to extend the thumb. Nerve, posterior interosseous.
Extensor Bievis Pollicis (Extensor Primi Internodii Pollicis) (n), — from
the posterior surface of the shaft of the radius and the interosseous mem-
brane: into the base of the ist phalanx of the thumb. Action, to extend
the thumb. Nerve, posterior interosseous.
Extensor Longus Pollicis (Extensor Secundi Internodii Pollicis) (m), —
from the shaft of the ulna posteriorly and the interosseous membrane:
into the base of the last phalanx of the thumb. Action, to extend the
thumb. Nerve, posterior interosseous.
Extensor Indicis (m. extensor indicis proprius) ,— from the shaft of the
ulna posteriorly and the interosseous membrane: into the 2d and 3d
phalanges of the index finger with the tendon of the common extensor.
Action, to extend the index finger. Nerve, posterior interosseous.
FASCIAE OF THE HAND
Anterior Annular Ligament (1. carpi transversum), — from the pisi-
form and unciform (hamate) bones: to the tuberosity of the scaphoid
(navicular) and the ridge on the trapezium (great multangular).
Inserted into its anterior surface are parts of the tendons of the
palmaris longus and the flexor carpi radialis, and beneath it pass the
tendons of the superficial and deep flexors of the fingers and the
flexor longus pollicis, also the median nerve. It is continuous with
the palmar fascia and the deep fascia of the forearm.
Posterior Annular Ligament (1. carpi dorsale) (o),—from the ulna, cunei-
form and pisiform bones: to the margin of the radius and the ridges on
its posterior surface. It has 6 canals for the passage of the extensor
tendons, each lined by a synovial membrane. It is continuous with the
deep fascia of the forearm.
Deep Palmar Fascia,— ensheaths the muscles of the hand, and divides
into 4 slips for the four fingers, each slip dividing and forming tendinous
arches for the passage of the flexor tendons of the fingers.
106 HUMAN ANATOMY
MUSCLES OF THE HAND
Abductor Pollicis (m. abductor pollicis brevis) (n), — from the ridge of the
trapezium (great multangular) the tuberosity of the scaphoid (navicu-
lar) and the annular ligament (1. carpi transversum) : into the radial
side of the base of the ist phalanx of the thumb. Action, to draw the
thumb from the median line. Nerve, median.
Opponens Pollicis, — from the palmar surface of the trapezium (great mult-
angular) and the annular ligament (1. carpi transversum): into the radial
side of the metacarpal bone of the thumb, for its whole length. Action,
as a flexor ossis metacarpi pollicis. Nerve, median.
Flexor Brevis Pollicis (12), — the outer portion from the lower border of the
annular ligament (1. carpi transversum), the inner and deeper portion
from the ulnar side of the ist metacarpal bone: into both sides of the
base of the ist phalanx of the thumb, by two tendons, each having a
sesamoid bone in it. Action, to flex the thumb. Nerves, median and
ulnar.
Adductor Obliquus Pollicis (m. adductor pollicis), — from the os magnum,
the bases of the 2d and 3d metacarpal bones, the anterior carpal liga-
ments and the sheath of the tendon of the flexor carpi radialis: into the
ulnar side of the base of the ist phalanx of the thumb, having a sesamoid
bone in the tendon of insertion. Action, to draw the thumb toward the
median line. Nerve, ulnar.
Adductor Transversus Pollicis,—; from the lower two-thirds of the meta-
carpal bone of the middle finger: into the ulnar side of the base of the ist
phalanx of the thumb. Action, as the preceding muscle. Nerve, ulnar.
[The above-mentioned 5 muscles of the thumb occupy the radial side of
the hand and form the Thenar Eminence; the first 4 of the folio wing- men-
tioned muscles occupy the ulnar side of the hand and form the Hypothe-
nar Eminence.]
Palmaris Brevis (10), — from the annular ligament and palmar fascia: into
the skin on the ulnar border of the palm of the hand. Action, to corru-
gate the skin of the hand. Nerve, ulnar.
Abductor Minimi Digiti (m. abductor digiti quinti), — from the pisiform
bone and the tendon of the flexor carpi ulnaris: -into the ulnar side of
the base of the ist phalanx of the little finger and the aponeurosis of the
extensor minimi digiti. Action, as indicated by its name. Nerve,
ulnar.
Flexor Brevis Minimi Digiti (m. flexor digiti quinti brevis),— from the
hook of the unciform bone and the annular ligament (1. carpi trans-
MUSCLES OF THE LOWER EXTREMITY 1 07
versum) : into the base of the proximal phalanx of the little finger, with
the preceding muscle. Action, as named. Nerve, ulnar.
Opponens Minimi Digiti (m. opponens digiti quinti), — from the unciform
or hamate bone and the annular ligament (1. carpi transversum) : into
the whole ulnar margin of the 5th metacarpal bone. Action, a flexor
of the 5th metacarpal bone. Nerve, ulnar.
Lumbricales 4, — from the tendons of the deep flexor: into the expanded
tendons of the common extensor on the dorsi of the phalanges. Action,
to dorsiflex the proximal phalanges. Nerves, median and ulnar. These
muscles have no sheaths.
Dorsal Interossei 4, — by 2 heads from the adjacent sides of the meta-
carpal bones: into the bases of the proximal phalanges of the index,
middle, and ring fingers, the middle finger having two. Action, abduc-
tors of the fingers from the median line of the hand. Nerve, ulnar.
Palmar Interossei (mm. interossei volares) 3, —from the palmar surfaces
of the 2d, 4th, and 5th metacarpal bones: into the bases of the proximal
phalanges of the same fingers. Action, adductors of the fingers. Nerve,
ulnar.
MUSCLES OF THE LOWER EXTREMITY
MUSCLES AND FASCIAE OF THE ILIAC REGION
ILIAC FASCIA, — is an aponeurotic layer which lines the back of the abdom-
inal cavity and covers the psoas and iliacus muscles throughout their
whole extent. It is attached above to the ligamentum arcuatum inter-
num (medial lumbo-costal arch), internally by arched processes to the
bodies of the vertebrae, also to the sacrum and the brim of the true pelvis;
externally it is continuous with the lumbar fascia above and is attached
to the whole length of the inner border of the crest of the ilium; below
it is continuous with the fascia transversalis and the pubic part of the
fascia lata of the thigh, is intimately connected to Poupart's (1. inguinale)
ligament, and is prolonged backward and inward therefrom as a band,
the Ilio-pectineal Ligament, to the ilio-pectineal eminence. It descends
behind the femoral vessels into the thigh, forming the posterior wall of
the femoral sheath. Transversalis Fascia lines the anterior abdominal
wall.
Psoas Magnus (m. psoas major) (n},—from the bodies, transverse proc-
esses, and intervertebral substances of the last thoracic and all the
lumbar vertebrae: into the lesser trochanter of the femur, by a common
tendon with the iliacus. Action, to flex the thigh upon the pelvis, and
when the femur is fixed to bend the trunk forward. Nerves, anterior
branches of the 2nd and 3rd lumbar.
108 HUMAN ANATOMY
Psoas Parvus (m. psoas minor),— from the bodies of the last thoracic and
first lumbar vertebrae and the intervertebral substance: into the ilio-
pectineal eminence and the iliac fascia. Action, when present it is a
tensor of the iliac fascia. Nerve, anterior branch of the ist lumbar.
Iliacus (10), — from the iliac fossa, inner margin of the iliac crest, ilio-lum-
bar ligament, base of the sacrum, anterior spinous processes of the ilium
and the notch between them: into the outer side of the tendon of the
psoas magnus, and the capsule of the hip- joint. Action, the same as
that of the psoas magnus. Nerve, anterior crural.
MUSCLES AND FASCIJE OF THE THIGH
SUPERFICIAL FASCIA, — forms a continuous fatty covering over the whole
thigh, in which lie the superficial vessels and nerves. The superficial
layer is continuous above with Camper's fascia of the abdomen. The
deep fibrous layer (Scarpa's fascia) covers the saphenous opening in
the fascia lata (see below), where it is perforated for the internal
saphenous vein and numerous vessels, and is therefore called the Crib-
riform Fascia in this situation. It forms one of the coverings of
a femoral hernia.
FASCIA LATA, — the deep fascia of the thigh, extends from Poupart's liga-
ment to the prominent points around the knee-joint, and from the mar-
gin of the sacrum and coccyx around the limb to the pubic arch and
pectineal line. It sends two strong intermuscular septa down to the
linea aspera, and contains the Saphenous Opening (fossa ovalis), which
is formed by the reflected margins of its pubic and iliac portions. The
structure named PouparCs Ligament (1. inguinale) is made by the knife,
and is only the line of junction between the aponeurosis of the external
oblique muscle and the fascia lata; extending from the anterior superior
spine of the ilium to the spine of the pubic bone.
Tensor Vaginae Femoris (m. tensor fasciae latae) (4), — from the anterior
part of the outer lip of the iliac crest, the anterior superior spinous
process and part of the notch below it, also from the fascia covering
the gluteus medius: into the fascia lata, between its two layers, about
one-fourth down the outer side of the thigh. Action, a tensor of the
fascia lata. Nerve, superior gluteal.
Sartorius (5),— -from the anterior superior spine of the ilium (2) and half of
the notch below it : into the upper internal surface of the shaft of the tibia.
Action, to flex and cross the legs. Nerve, anterior crural.
Quadriceps Extensor (m. quadriceps femoris), — including the 4 remain-
ing muscles on the front of the thigh, — the rectus femoris, vastus exter-
MUSCLES OF THE THIGH
FIG. 55.
nus (m. vastus lateralis), vastus interims (m. vastus medialis), and the
crureus (m. vastus intermedius). Its tendon is inserted into the
patella. Action, the great extensor of the leg. Nerve, anterior crural.
Rectus Femoris (6), — by two tendons, the Straight
from the anterior inferior spine of the ilium, the
Reflected from a groove above the brim of the
acetabulum: into the patella by a flattened
tendon (9) which is common to this and the
next 3 muscles. Action, to extend the leg.
Nerve, anterior crural (n. femoralis).
Vastus Externus (m. vastus lateralis) (7),— from
the anterior border of the great trochanter and
part of the linea aspera of the femur: into the
outer border of the patella, by a flat tendon
which blends with the great extensor tendon.
Action, to extend the leg. Nerve, anterior
crural (n. femoralis).
Vastus Interims (m. vastus medialis) (8),— from
the anterior intertrochanteric line, the spiral
line, the linea aspera, the internalsupracondylar
line, the tendon of the adductor magnus and the
intermuscular septum: into the inner border of
the patella and the great extensor tendon.
Action, to extend the leg. Nerve, anterior crural
(n. femoralis).
Crureus (m. vastus intermedius), — from the upper
two-thirds of the shaft of the femur and the
intermuscular septum: into the great extensor
tendon. Action, to extend the leg. Nerve, an-
terior crural. This muscle and the vastus in-
ternus appear to be inseparably united, but
they can be separated.
Subcrureus (m. articularis genu), — often blended with the crureus : from
the lower part of the shaft of the femur anteriorly; — into the capsular
ligament behind the patella. Action, to draw up the capsular ligament.
Nerve, anterior crural.
Oracilis (15),— from the margin of the symphysis and the anterior half of
the pubic arch: into the inner surface of the shaft of the tibia below the
tuberosity ( medial condyle). Action, to flex theleg and rotate it in ward,
also to adduct the thigh. Nerve, obturator.
no
HUMAN ANATOMY
FIG. 56.
Pectineus (12),— -from the ilio-pectineal line, and the bone in front thereof,
also from the fascia covering the muscle: into the rough line extending
from the trochanter minor to the linea aspera. Action, to adduct the
thigh and rotate it outward. Nerves, accessory obturator, anterior
crural (n. femoralis).
Adductor Longus (13), —from the front of the os pubis: into the middle
third of the linea aspera. Action, to adduct the thigh powerfully.
Nerve, obturator.
Adductor Brevis, — from the body and descending ramus of the os pubis;
into the upper part of the linea aspera. Action,
to adduct the thigh. Nerve, obturator.
Adductor Magnus (14),— from the descending
ramus of the os pubis, the ramus of the ischium,
and the outer margin and under surface of the
tuberosity of the ischium: into the rough line
leading from the great trochanter to the linea
aspera, the whole length of the linea aspera, and
by a tendon into the tubercle on the inner
condyle of the femur. Action, to adduct the
thigh and rotate it outward. Nerves, obturator
and great sciatic. This muscle is pierced by 4
apertures for the 3 superior perforating and the
prof unda arteries, and about the lower one-third
of its insertion an angular interval is left
therein, the lower opening of Hunter's canal
(femoral canal), for the passage of the femoral
vessels into the popliteal space.
MUSCLES OF THE HIP
Gluteus Maximus (m. glutseus maximus) (b), —
from the posterior gluteal line of the ilium, the
crest behind it, the last piece of the sacrum, the
side of the coccyx, the great sacro-sciatic liga-
ment, the aponeurosis of the erector spinae and
the fascia covering the gluteus medius : into the
fascia lata and the rough line leading from the
great trochanter to the linea aspera. Action, to extend and abduct the
thigh and rotate it outward, also to maintain the trunk erect. Nerves,
inferior gluteal from the sacral plexus.
Gluteus Medius (m. glutaeus medius) (a},— from the ilium between the
MUSCLES OF THE HIP
III
posterior gluteal and the anterior gluteal lines, the crest between them,
and the fascia of the part: into the oblique lines on the great trochanter.
Action, its posterior fibres rotate the thigh outward, its anterior fibres
rotate inward. It also abducts the thigh and draws it forward, and
assists to maintain the trunk erect. Nerve, superior gluteal.
Gluteus Minimus (m. glutaeus minimus) (8) —from the ilium between the
anterior and inferior gluteal lines, and the margin of the great sacro-
sciatic notch: into the anterior border of the great trochanter. Action,
to rotate the thigh inward, also to abduct and draw it forward, and to
maintain the trunk erect. Nerve, superior gluteal.
Pyriformis (9), — by 3 digitations from the front of the sacrum, from the
margin of the great sacro-sciatic foramen and the great sacro-sciatic
ligament (1. sacro-tuberosum) : into the upper border of the great tro-
chanter (7), having passed through the great sacro-sciatic foramen.
Action, an external rotator of the
thigh. Nerves, first and second FIG. 57.
sacral.
Obturator Interims (n), — from the
posterior bony margin of the ob-
turator foramen and the inner sur-
face of the obturator membrane: into
the great trochanter (7), passing
through the lesser sacro-sciatic fora-
men. Action, an external rotator of
the thigh. Nerve, a special nerve
from sacral plexus to the obturator
internus.
Gemellus Superior (io),from the outer
surface of the spine of the ischium:
into the great trochanter, being
blended with the tendon of the ob-
turator internus. Action, an ex-
ternal rotator of the thigh. Nerve,
the special nerve to the obturator
internus from the sacral plexus.
Gemellus Inferior (12), from the tuberosity of the ischium: into the
tendon of the obturator internus and the great trochanter. Action,
an external rotator of the thigh. Nerve, the special nerve from the
sacral plexus to the quadratus femoris.
112 HUMAN ANATOMY
Quadratus Femoris (13),— from the tuberosity of the ischium: into the
upper part of the linea quadrata on the trochanter major posteriorly.
Action, an external rotator of the thigh. Nerves, a special branch of
the sacral plexus.
Obturator Externus, — from the anterior inner bony margin of the ob-
turator foramen, and the inner two-thirds of the anterior surface of the
obturator membrane: into the trochanteric or digital fossa of the femur.
Action, an external rotator of the thigh. Nerve, obturator.
Biceps (m. biceps femoris) (16), — by 2 heads, the Long Head (d) from the
tuberosity of the ischium posteriorly, the Short Head (e) from the outer
lip of the linea aspera, and the intermuscular septum: into the outer
side of the head of the fibula; its tendon embracing the external lateral
(fibular collateral) ligament of the knee-joint and forming the Outer
Hamstring, the tendons of the semi-tendinosus, semi-membranosus,
gracilis and sartorius forming the Inner Hamstring. Action, to flex
the leg and rotate it outward. Nerve, great sciatic.
Semi-tendinosus (f),—from the tuberosity of the ischium by a tendon
(4) common to it and the long head of the biceps, and from the adjacent
aponeurosis: into the shaft of the tibia at its upper and inner surface,
its tendon curving around the inner tuberosity (medial condyle).
Action, to flex the leg upon the thigh. Nerve, great sciatic.
Semi-membranosus (g), — from the tuberosity of the ischium above the
origin of the above-named two muscles: into the inner tuberosity (medial
condyle) of the tibia; its tendon of insertion giving off fibrous expan-
sions one to the outer condyle of the femur forming part of the pos-
terior ligament of the knee-joint, another to the fascia .covering the
popliteus muscle, and fibres to the internal lateral (tibial collateral)
ligament of the joint. Action, to flex the leg, and rotate it inward.
Nerve, great sciatic.
External Rotators of the Hip-joint are 13^, — the 3 adductors, pyriformis,
2 obturators, 2 gemelli, quadratus femoris, pectineus, psoas magnus,
iliacus, sartorius, and posterior half of the gluteus medius.
Internal Rotators of the Hip-joint are 2^, — the tensor vaginae femoris,
gluteus minimus, and the anterior half of the gluteus medius.
MUSCLES OF THE LEG
Tibialis Anti'cus (m. tibialis anterior) (3),— -from the outer tuberosity
(lateral condyle) and upper two-thirds of the shaft of the tibia externally,
the interosseous membrane, deep fascia, and intermuscular septum;
through the inner canal in the anterior annular ligament (11. transversum
MUSCLES OF THE LEG
PIG. 58.
et cruciatum cruris) : into the inner and plantar surface of the internal
cuneiform bone, and the base of the ist metatarsal. Action, to flex
the tarsus on the leg, and elevate the inner border of the foot. Nerve,
anterior tibial.
Extensor Proprius Hallucis (m. extensor hallucis longus) (5),— from the
middle two-fourths of the fibula anteriorly and the interosseous mem-
brane, through the 2d canal in the anterior annular ligament: (1. trans-
versum cruris et 1. cruciatum cruris) : into the base of the terminal or
distal phalanx of the great toe. Action, to
extend that toe. Nerve, anterior tibial (deep
peroneal nerve).
Extensor Longus Digitorum (m. extensor digi-
torum longus) (4), — from the outer tuberosity
(lateral condyle) of the tibia the upper three-
fourths of the extensor surface of the shaft of
the fibula anteriorly, interosseous membrane,
deep fascia, and intermuscular septa: into the
2d and 3d phalanges of the 4 lesser toes, by 4
tendons which pass over the dorsum of the
foot from the outer canal in the anterior an-
nular ligament (11. transversum et cruciatum
cruris). Action, to extend the lesser toes.
Nerve, anterior tibial (deep peroneal).
Peroneus Tertius (m. peronasus tertius) (6), —
from the outer lower fourth of the extensor
surface of the fibula, interosseous membrane
and intermuscular septum: into the base of
the 5th metatarsal bone. This muscle is a
part of the last-named, and passes through the
same canal in the annular ligament (11. trans-
versum et cruciatum cruris). Action, to dorsi-
flex the tarsus. Nerve, anterior tibial (deep
peroneal).
Gastrocnemius, — by 2 heads (9, 10), from the
condyles of the femur, and the supra-condylar
ridges: unites with the tendon of the soleus to form the tendo Achillis,
into the posterior tuberosity of the os calcis (calcaneus). Action, to
extend the foot or flex the calcaneus. Nerve, internal popliteal (n.
tibialis).
/ Soleus,— from the head and upper third of the flexor surface of the shaft
8
HUMAN ANATOMY
FIG. 59.
of the fibula posteriorly, the oblique line of the tibia, and the tendinous
arch: unites with the tendon of the gastrocnemius as the tendo A chillis
(see above). Action, to extend the foot and flex the heel. Nerves,
internal popliteal, posterior tibial (nn. tibialis).
Plantaris, — from the outer bifurcation of the linea aspera and the posterior
ligament of the knee-joint: by a very long, delicate tendon into the
posterior surface of the os calcis. Action, to extend the foot and flex the
heel. Nerve, internal popliteal (n. tibialis).
Popliteus (6 Fig. 59), — from a depression on the external (lateral) condyle
of the femur, and the posterior ligament of the knee-
joint: into the inner two-thirds of the triangular surface
on the shaft of the tibia (2) posteriorly and above the
oblique line. Action, to flex the leg. Nerve, internal
> popliteal (n. tibialis).
Flexor Longus Hallucis (m. flexor hallucis longus) (9), —
from the lower two-thirds of the flexor surface of the
shaft of the fibula, the interosseous membrane, fascia,
and intermuscular septum, its tendon passing through
grooves in the tibia, astragalus and os calcis: into the
base of the last phalanx of the great toe. Action, to
flex the great toe. Nerve, posterior tibial (n. tibialis).
Flexor Longus Digitorum (m. flexor digitorum longus)
(7) —from the shaft of the tibia posteriorly and below
the oblique line; its tendon passing behind the inner
I? malleolus in a groove (13) with the tibialis posticus
(m. tibialis posterior): into the bases of the last
phalanges of the lesser toes by 4 tendons which per-
forate the tendons of the flexor brevis digitorum.
Action, to flex the phalanges and extend the foot.
I Nerve, posterior tibial (n. tibialis).
Tibialis Posti'cus (m. tibialis posterior) (8), — by two
processes between which pass the anterior tibial ves-
sels, from the upper half of shaft of the tibia poste-
riorly, the upper two-thirds of the flexor surface of the
shaft of the fibula internally, the interosseous mem-
brane, deep fascia, and intermuscular septa; its ten-
don passes behind the inner malleolus in a groove (13) with the long
flexor: into the tuberosity of the scaphoid and internal cuneiform bones.
Action, to extend the tarsus and invert the foot. Nerve, posterior tibial
(n. tibialis).
MUSCLES OF THE LEG 115
Peroneus Longus (m. peronaeus longus) (io),—from the head of the fibula,
and the upper two-thirds of the peroneal surface of its shaft externally,
the deep fascia and intermuscular septa, passes behind the outer malleo-
lus in a groove with the peroneus brevis, through a groove in the cuboid
bone: into the outer side of the base of the metatarsal bone of the great
toe and the internal cuneiform bone, having crossed the sole of the foot
obliquely. Action, to extend and evert the foot and flex the heel.
Nerve, musculo-cutaneous branch of the external popliteal (n. peronaei
superficialis).
/Peroneus Brevis (m. peronaeus brevis) (n), — from the middle third of the
peroneal surface of the shaft of the fibula externally and the inter-
muscular septa: its tendon passes behind the external malleolus in a
groove with the long peroneal, into the dorsum of the base of the 5th
metatarsal bone. Action, to extend the foot. Nerve, musculo-cutane-
ous branch of the external popliteal (n. peronaei superficialis).
FASCIA OF THE FOOT
ANTERIOR ANNULAR LIGAMENT (11. transversum et cruciatum cruris)
(12 Fig. 58), — consists of vertical and horizontal portions, is attached
to the lower ends of the fibula and tibia, the os calcis and the plantar
fascia. It contains sheaths lined by synovial membranes for the ten-
dons of the extensor muscles (that of the extensor proprius hallucis
passing beneath it), as also the anterior tibial vessels and nerve.
INTERNAL ANNULAR LIGAMENT (1. laciniatum),— from the inner malleolus
to the os calcis (calcaneus), converting 4 bony grooves into canals lined
by synovial membranes for the flexor tendons and the posterior tibial
vessels and nerves.
EXTERNAL ANNULAR LIGAMENT (1. peronaei retinaculum superior),— front
the outer malleolus to the os calcis, binding down the peronei tendons
in one synovial sac.
i / PLANTAR FASCIA, — the densest in the body, divided into a central and two
lateral portions, and attached to the inner tuberosity of the os calcis,
f divides into 5 processes, i for each toe, and several intermuscular septa.
^ DORSAL FASCIA, — is a thin membranous layer continuous above with the
anterior margin of the annular ligament, and becoming gradually lost
opposite the heads of the metatarsal bones, and on each side blending
with the plantar fascia. It forms a sheath for the tendons on the dorsum
of the foot.
MUSCLES or THE FOOT
Extensor Brevis Digitorum (m. extensor digitorum brevis) (n Fig. 58), —
the only muscle on the dorsum of the foot, arises from the os calcis
Il6 HUMAN ANATOMY
externally, the calcaneo-astragaloid and the anterior annular ligaments
(1. cruciatum cruris): — by 4 tendons, i into the proximal phalanx of
the great toe, and the others into the outer sides of the long extensor
tendons of the 2d, 3d, and 4th toes. A ction, to extend the toes. Nerve,
anterior tibial (deep peroneal).
Muscles on the sole of the foot number 19; arranged by layers: —
ist Layer 3d Layer
Abductor Hallucis. Flexor Brevis Hallucis (m. flexor hallu-
cis brevis).
Flexor Brevis Digitorum (m. Adductor Obliquus Hallucis (caput obli-
flexor digitorum brevis). quum m. adductoris hallucis).
Abductor Minimi Digiti (m. Flexcr Brevis Minimi Digiti (m. flexor
abductor digiti quinti). digiti quinti brevis).
2d Layer Adductor Transfer sus Hallucis (caput
Flexor Accessorius (m. quad- transversum m. adductoris hallucis).
ratus plantae). 4th Layer
Lumbricales, 4. Interossei (4 Dorsal, 3 Plantar).
Abductor Hallucis,*- from the inner tubercle of the os calcis (calcaneus),
the internal annular ligament (1. laciniatum), plantar fascia, and inter-
muscular septum: into the inner side of the base of the ist phalanx of
the great toe. Action, to abduct the great toe. Nerve, internal plantar
(n. plantaris medialis).
Flexor Brevis Digitorum (m. flexor digitorum brevis),— from the inner
tubercle of the os calcis (calcaneus) (n), the plantar fascia and inter-
muscular septa: into the sides of the 2d phalanges of the lesser toes by 4
tendons (5) which are perforated for the long flexor tendons (2). Action,
to flex the lesser toes. Nerve, internal plantar (n. plantaris medialis).
Abductor Minimi Digiti (m. abductor digiti quinti),— from the tubercles
and under surface of the os calcis (calcaneus) (n), the plantar fascia and
the intermuscular septum: into the base of the proximal phalanx of the
little toe with the tendon of its short flexor. Action, to abduct the little
toe. Nerve, external plantar (n. plantaris lateralis).
Flexor Accessorius (m. quadratus plantae) (i), — by 2 heads, from the os
calcis (calcaneus) and the long plantar ligament : into the tendon of the
flexor longus digitorum. Action, accessory flexor of the toes. Nerve,
external plantar (n. plantaris lateralis).
Lumbricales (4), iour,from the long flexor tendons: each into the dorsum of
the proximal phalanx of the corresponding toe. Action, accessory
MUSCLES OF THE FOOT 1 17
flexors of the toes and to dorsiflex the proximal phalanges. Nerves, in-
ternal plantar (n. plantaris medialis) to the innermost lumbrical,
external plantar (n. plantaris lateralis) to the other three.
Flexor Brevis Hallucis (m. flexor hallucis brevis) (7),— -from the cuboid
and external cuneiform bones, and the prolonged tendon of the tibialis
posticus (m. tibialis posterior) : into both sides of the base of the proximal
phalanx of the great toe, by 2 portions, of which one blends with the
abductor hallucis, the other with the adductor ob-
liquus hallucis. Action, to flex the great toe.
Nerve, internal plantar (n. plantaris medialis).
Adductor Obliquus Hallucis (caput obliquum m.
adductoris hallucis), — from the tarsal ends of
the three middle metatarsal bones, and the
sheath of the tendon of the peroneus longus:
into the base of the proximal phalanx of the
great toe, externally. Action, to adduct the
great toe. Nerve, external plantar (n. plantaris
lateralis) .
Flexor Brevis Minimi Digiti (m. flexor digiti quinti
brevis) (6), — from the base of the 5th metatarsal
bone (9) and the sheath of the tendon of the pero-
neus longus: into the base of the proximal
phalanx of the little toe externally. Action, to
flex the little toe. Nerve, external plantar (n.
plantaris lateralis.)
Adductor Transversus Hallucis (caput transversum
m. adductoris hallucis) (Transversus Pedis),— from
the inferior metatarso-phalangeal ligaments of
the three outer toes and the transverse ligament of the metatarsus:
into the outer side of the proximal phalanx of the great toe, blending with
the tendon of the adductor obliquus hallucis. Action, to adduct the
great toe. Nerve, external plantar (n. plantaris lateralis).
Dorsal Interossei (4), — each by two heads from the adjacent sides of
two metatarsal bones: into the base of the proximal phalanx of the
corresponding toe. Action, to abduct the toes. Nerve, external plantar.
Plantar Interossei 3,— from the shafts of the 3d, 4th, and 5th metatarsai
bones: into the bases of the proximal phalanges of the same toes. Ac-
tion, to adduct the toes toward the median line. Nerve, external plantar
(n. plantaris lateralis).
Il8 HUMAN ANATOMY
THE BLOOD-VASCULAR SYSTEM
THE HEART OR COR
The Pericardium is a conical membranous sac, containing the heart and
the roots of the great vessels. It lies behind the sternum and between the
plurae, its apex upward, its base attached to the central tendon of the dia-
phragm. It is composed of an outer fibrous coat, and an inner serous one;
the former is prolonged on the outer surfaces of the great vessels, except
the inferior vena cava, and becomes continuous with the deep layer of the
cervical fascia; the latter consists of a parietal layer, lining the inner sur-
face of the fibrous coat, and a visceral layer, which is reflected over the
heart and vessels. The serous portion secretes a thin fluid, about i drachm
in quantity normally, for the lubrication of its surfaces. Arteries, are
derived from the internal mammary and its musculo-phrenic branch, and
from the descending thoracic aorta. Nerves, are branches from the vagus,
the phrenic and the sympathetic.
The Endocardium is a thin, smooth, transparent membrane, which lines
the internal surface of the heart; assisting by its reduplications in forming
the valves, and being continuous with the lining membrane of the great
blood-vessels.
JThe Heart (cor) is a hollow muscular organ, conoidal in shape, placed
obliquely in the chest between the lungs, base upward, apex to the left and
front, corresponding to the space between the 5th and 6th costal cartilages,
% inch inside of and i^ inch below the left nipple. In the adult its size
is about 5 inches by 3^ by 2%, and from 10 to 12 oz. in weight in the male,
8 to 10 oz. in the female.
The Cavities of the Heart are 4 in number, an atrium and ventricle on
each side of the heart; the cavities on one side being separated from those
of the other side by a longitudinal muscular septum. The division into 4
cavities is indicated on the external surface of the organ by grooves, named,
from their contiguous cavities, the auricula-ventricular groove transversely,
and the inter-ventricular grooves longitudinally.
Structure of the Heart. The muscular fibres forming the heart take
origin from four fibrous rings at the auriculo-ventricular and aortic open-
ings. The fibres of the auricles are arranged in two layers, a superficial
and a deep one, the latter having looped fibres and annular fibres. In the
ventricles the fibres are also superficial and deep, the latter being arranged
circularly, the former spirally, coiling inward at the apex of the heart into a
whorl-like form, the vortex.
THE HEART
IIQ
FIG. 61.
Vessels and Nerves. The Arteries are the right and left coronary from
theTaorta. The Veins accompany the arteries and terminate in the right
auricle. The Lymphatics, terminate in the thoracic and right lymphatic
ducts. The N> / are derived from the cardiac plexuses, which are
formed partly f vhe cranial nerves and partly from the sympathetic.
THE RIGHT HEART
The Right Auricle (atrium dextrum) is slightly larger than the left, its
walls somewhat thinner, being about one line in thickness; its cavity con-
tains about 2 fluidounces. It consists of two parts, a principal cavity, the
sinus venosus (i) or atrium,
situated posteriorly, and a
smaller portion, the appendix
auricula (auricula dextra) (2),
situated anteriorly. It re-
ceives the venous blood by
the superior (3) and inferior
(4) venae cavae and the coro-
nary sinus, and presents in-
teriorly the following points
for examination:—
Appendix Auricula (auric-
ula dextra) (n), — a con-
ical pouch projecting from
the sinus to the front and
left, its margins being
dentq,ted.
Openings — of the superior
and inferior venae cavae and the coronary sinus (7), the latter having
a valve in two segments.
foramina Thebesii (foramina venarum minimarum), — several minute
orifices, the mouths of veins from the substance of the heart.
Auricula-ventricular Opening (ostium venosum dextrum) (9), — com-
municates with the right ventricle, is oval, about i% inch broad,
surrounded by a fibrous ring, and is guarded by the tricuspid valve.
Fossa Ovalis (5), — a depression on the inner wall, corresponding to the
situation of the foramen ovale in the foetus.
Annulus Ovalis (limbus fossae ovalis [Vieussenii]), — the oval margin of
the fossa ovalis.
Musculi Pectinatij — muscular columns on the inner surface of the appen-
dix and the inner wall of the auricle.
120 HUMAN ANATOMY
Tubercle of Lower (tuberculum intervenosum [Lower!]), — a very small
projection on the right wall, supposed to influence the direction of the
blood-current.
Eustachian Valve (valvula venae cavae inferioris [Eustachii]) (6), — at
the anterior margin of the inferior vena cava; large in the foetus, to
direct the blood to the foramen ovale.
Coronary Valve (valvulae sinus coronarii [Thebesii]) (Valve of Thebe-
sius) (8), — a semicircular fold which protects the orifice of the
coronary sinus and prevents regurgitation of blood into the sinus.
The Right Ventricle (ventriculus dexter) (a) is triangular in form and
extends from the right auricle to near the apex of the heart. Its anterior
surface is rounded and convex and forms the larger part of the front of
the heart. Its under surface is flattened and rests upon the diaphragm.
Its cavity (b c) can contain about 3 fluidounces, and presents the following
points for examination: —
Tricuspid Valve (valvula tricuspidalis) (e, /), — consists of 3 triangular
segments connected by their bases with the auriculo-ventricular ori-
fice, and by their sides with each other, the largest being on the left
side.
Semilunar Valves (valvulse semilunares a. pulmonalis) (m), — are 3 in
number, and guard the orifice of the pulmonary artery; each about
the middle of its free margin has a fibrocartilaginous nodule, the
corpus Arantii (noduli valvarum semilunarum [Arantii]), which
more perfectly closes the orifice.
Opening of the Pulmonary Artery (ostium arteriosum pulmonis), — at the
superior and internal angle of the ventricle, the conus artericsus. It
is circular in form, surrounded by a fibrous ring, and is guarded by
three semilunar valves.
Sinuses of Valsalva, — are 3 pouches, one behind each valve, between it
and the commencement of the pulmonary artery.
Columns Ccrnece, (trabeculae carnae) (g), — muscular columns projecting
from the surface of the ventricle, of which 3 or 4, called musculi
papillares, give attachment to the chordae tendinae.
Chorda Tending (1), — delicate tendinous cords which connect the mar-
gins and lower surfaces of the tricuspid valve with the columnae.
THE LEFT HEART
The Left Auricle (atrium sinistrum) is smaller than the right, but has
thicker walls, being about i^ line. Like the right auricle it consists of a
principal cavity (i) or sinus (atrium) and an appendix auricula (auricula
THE HEART
121
sinistra, (2), which overlaps the root of the pulmonary artery. Internally
the auricle presents the following parts: —
Openings (3) of the Pulmonary Veins, — are 4 in number, sometimes 3, as
the two left veins (5) frequently end in a common opening. They
have no valves.
Left Auricula-ventricular Opening (ostium venosum ventriculi sinistri)
(6), — is smaller than the right one.
Musculi Peciinati, — on the inner surface of the appendix.
Depression, — corresponding to the fossa ovalis in the right auricle.
FIG. 62.
The Left Ventricle (ventriculus sin-
ister) (8) is longer, thicker and more
conical in shape than the right ven-
tricle (/O, and it forms a small part of V-
the anterior surface of the heart but
a considerable part of its posterior
surface. By its projection beyond
the apex of the right ventricle it
forms the apex of the heart. Its walls
are the thickest of those in the heart,
being thrice as thick as those of the
right ventricle. Its interior (9) pre-
sents the following: —
Left Auricula-ventricular Opening
(ostium venosum ventriculi sin-
istri),— is surrounded by a dense
fibrous ring (annulus fibrosus sin-
ister) and is guarded by the mitral
valve (valvula bicuspidalis).
Aortic Opening (ostium arteriosum), — is small and circular, placed in
front and to the right of the auriculo-ventricular, a segment of the
mitral (bicuspid) valve being between them. It is surrounded by a
fibrous ring, and guarded by the semilunar valves (valvulae semi-
lunares aortae).
Mitral Valve (valvula bicuspidalis) (a), — consists of two unequal-
sized segments, and is attached to the fibrous ring which surrounds
the auriculo-ventricular opening (ostium venosum ventriculi sinistri).
Its margins are connected with the ventricular walls by chordae
tendinae and musculi papillares.
Semilunar Valves (valvulae semilunares aortae), — 3 in number ggjuard the
aortic orifice, and are larger and stronger than those on the right side.
122 HUMAN ANATOMY
Sinus of Valsalva, — a pouch in the wall of the aorta opposite each seg-
ment of the semilunar valves.
ColumncB Carnea (6), — are smaller and more numerous than those on
the right side; the musculi papillares are but two in number, one con-
nected to the anterior, the other to the posterior wall.
THE ARTERIES
The Arteries are cylindrical tubular vessels which carry blood from the
ventricles of the heart to every part of the body. The Aorta and its
branches, together with the returning veins, constitute the greater or
systemic circulation. The Pulmonary Artery and its branches to the lungs,
together with the returning veins, constitute the lesser or pulmonic cir-
culation. The arteries anastomose or communicate freely with each
other everywhere throughout the body, permitting the establishment of
collateral circulations.
Structure of the Arteries. They are dense in structure, very elastic,
preserving their cylindrical form, and are composed of 3 coats, an Internal
or serous (tunica intima); a Middle (tunica media), composed of muscular
and elastic tissue; and an External (tunica externa or adventitia), com-
posed of connective tissue. They are generally included in a fibro-
areolar investment, the Sheath, which also encloses the accompanying veins.
The larger arteries are nourished by the Vasa Vasorum, blood-vessels
which ramify in the external and middle coats; and are supplied with
nerves, the Vaso-motor, derived from both the sympathetic and cerebro-
spinal systems, and forming intricate plexuses on the larger trunks.
The Capillaries are minute vessels forming a network throughout the
tissues of the body between the terminating arteries and the commencing
veins. Their average diameter is about the Hooo of an inch, average
length ^o of an inch and their walls consist of a transparent homoge-
neous membrane continuous with the innermost layer of the arterial
and venous walls.
THE PULMONARY ARTERY AND AORTA
The Pulmonary Artery (a. pulmonalis) alone of the arteries carries
venous blood, which it conveys from the right side of the heart to the
lungs. It is i^-i inch in diameter and only about 2 inches long, and all
within the pericardium; arising from the right ventricle in front of the
ascending aorta, passing upward and backward to the under surface of
the arch of the aorta, where it bifurcates, and is connected at its root to
THE AORTA 123
the aorta by a fibrous cord, the remains of the ductus artcriosus of the
foetus. Its terminal branches are the —
Right (ramus dexter a. pulmonalis) and Left (ramus sinister a. pulmonalis)
Pulmonary Arteries, — the latter being tne" shorter of the two; they pass
horizontally outward to the roots of their respective lungs, where each
divides into two branches, which again and again subdivide to ramify
throughout the lung tissue and end in the capillaries of those organs.
The Aorta (arteria magna) is the main trunk of the systemic arteries,
commencing at the aortic opening of the left ventricle of the heart, it arches
backward over the roof of the left lung into the thorax, where it descends
on the left of the spinal column, and after passing through the aortic
opening in the diaphragm, it terminates in the right and left common
iliac arteries opposite the 4th lumbar vertebra. It is divided into the
^Ascending Aorta (aorta asc'ehdens) (5), the Arch (arcus aortae) (6), and
the Ascending Aorta (aorta descendens) (12), the last-named being again
divided into the Thoracic Aorta (aorta thoracalis) and the Abdominal
Aorta (aorta abddnimalis) (described under Arteries of the Trunk).
Th*e" upper border of the arch is generally situated about an inch below
the upper margin of the sternum. The branches of the aorta are —
From the Ascending Aorta, — 2 Coronary Arteries (4).
From the Arch, — Innominate (a. anonyma) (7). Left Common Carotid
(10). Left Subclavian (n).
From the Thoracic, — Pericardia!. (Esophageal. 18 Intercostals.
Bronchial. Posterior Mediastinal.
From the Abdominal,— 2 Phrenic.
{ Gastric.
Cceliac Axis. { Hepatic.
( Splenic (a. lienalis).
2 Spermatic, in the male.
2 Ovarian, in female. Inferior Mesenteric.
Superior Mesenteric. 8 Lumbar.
2 Supra-renal. Sacra Media.
2 Renal. 2 Common Iliac.
The Coronary Arteries are 2 in number, a right and a left (4), arise from
the aorta in the sinuses of Valsalva behind the semilunar valves, and run in
the vertical grooves of the heart, the left artery in front, to supply the
tissue of that organ. Each artery divides into 2 branches, the transverse
and the descending, the latter anastomosing at the apex of the heart with
its fellow of the opposite side. The descending branch of the right coro-
124
HUMAN ANATOMY
FIG. 63.
nary sends off a marginal branch along the margin of the right ventricle,
and an infundibular branch to the conus ar-
teriosus of the same ventricle.
The Innominate Artery (a. anonyma) (7)
arises from the summit of the arch of the
aorta, is i^ inch long, and divides behind
the right sternoclavicular joint into the Right
Common Carotid (9) and Right Subdavian (8),
these arteries on the left side of the body (10,
n) arising directly from the arch of the aorta.
It sometimes sends off a small branch, the
Thyroidea ima, to the thyroid body; which
vessel may arise from the arch of the aorta,
the right common carotid, the subclavian, or
the internal mammary. The Innominate
artery is sometimes absent and not infre-
quently varies in length from }$ inch to 2 inches.
ARTERIES OF THE HEAD AND NECK
The Common Carotid Arteries
(Arterae Carotides Communes).
Arising differently (see above)
the two carotids are similarly
described, except that the left
is longer and deeper than the
right one. Their course is indi-
cated by a line drawn from a
point midway between the
angle of the lower jaw and the
mastoid process to the sterno-
clavicular articulation. At the
lower part of the neck they are
separated only by the width of
the trachea, and they are each
contained in a sheath of the
deep cervical fascia with the
internal jugular vein externally
and the pneumogastric nerve
(n. vagus) between the artery
and vein. On the front of the
sheath lies the descendens hypo-
Pic. 64.
ARTERIES OF THE HEAD AND NECK 125
glossi nerve (descending branch of the i2th or hypoglossal). The
artery lies beneath the inner border of the sterno-cleido-mastoid muscle,
and is crossed about its middle by the omo-hyoid muscle and the middle
thyroid vein. It is also crossed above by the facial, lingual, and su-
perior thyroid veins, below by the anterior jugular vein, and on the left
side often by the internal jugular vein. It bifurcates, at the level of the
upper border of the thyroid cartilage, into the External and Internal
Carotids, of which the internal is the more remote from the median line.
The External Carotid Artery (a. carotis externa) (2) (Fig. 64) commences
opposite the upper border of the thyroid cartilage, and passes upward,
forward and backward to the space between the neck of the condyle of the
lower jaw and the external meat us, where it divides into the temporal and
internal maxillary arteries. It has 8 branches, the —
Superior Thyroid (a. thyreoidea superior) (4), — arising below the greater
cornu of the hyoid bone; giving off —
Muscular. Hyoid. Superior Laryngeal.
Glandular. Superficial Descending. Crico-thyroid.
Lingual (a. lingualis) (5), — under the hyo-glossus muscle to the tongue;
giving off —
Hyoid. Dorsalis Linguae. Sublingual. Ranine.
Facial (a. maxillaris externa), should be called superficial facial (6),—
crosses the lower jaw at the anterior border of the masseter; giving
off-
Inferior (Ascending) Palatine. Submental (7). 2 Coronary (aa. la-
Tonsillar. Muscular. biales) (8, 9).
Submandibular. Inferior Labial. Lateralis Nasi.
Angular.
Occipital (a. occipitalis) (10), — lies in the occipital groove of the temporal
bone.
Muscular. Auricular. Arteria Princeps Cervicis
Sterno-mastoid. Meningeal. (13) (ramus descen-
dens a. occipitalis).
Posterior Auricular (a. auricularis posterior) (14), — ascends under cover of
the parotid gland.
Stylo-mastoid. Auricular. Mastoid. Muscular. Glandular.
Ascending Pharyngeal, (a. pharyngea ascendens), — lies on the rectus
capitis anticus major.
Prevertebral. Pharyngeal. Tympanic. Meningeal.
126
HUMAN ANATOMY
FIG. 65.
Superficial Temporal (a. temporalis superficialis) (15), — the smallest of the
termini of the external carotid, begins in the parotid gland, crosses the
zygomatic arch, and divides into anterior (13) and posterior temporal
(16). Its branches are the —
Parotid. Articular. Zygomatico-orbital. Frontal. Parietal.
Transverse Facial (15). Middle Temporal (17). Anterior Auricular.
Internal Maxillary (a. maxillaris in-
terna), should be called deep facial
(4), — the other terminal branch
of the external carotid (i), is di-
vided into three portions, Maxil-
lary (4), Pterygoid (5), and
Spheno- maxillary (6), which re-
spectively give off the following
branches (Fig. 65):
Maxillary
Deep Auricular, to the tragus
and canal.
Anterior Tympanic (7), enter-
ing the Glaserian (petro-tym-
panic) fissure.
Middle Meningeal (8).
Small or Accessory Meningeal (9).
Inferior Alveolar or Dental (10), divides into Incisor and Mental.
Pterygoid
Deep Temporal, ant. and poste-
rior.
Pterygoid Branches, to those
muscles.
Masseteric, to the masseter mus-
cle.
Buccal, to the buccinator
muscle.
S pheno-maxillary
Posterior Superior Alveolar (n).
Infra-orbital (12).
Descend. Palatine (13).
Vidian (a. canalis pterygoidea)
(16).
Pterygo-palatine (15).
Spheno-palatine or Naso-paia-
tine (14).
Pharyngeal.
The Internal Carotid Artery (a. carotis interna) commences at the
bifurcation of the common carotid and ascends in front of the transverse
processes of the three upper cervical vertebrae, and close to the tonsil,
traverses the carotid canal in the temporal bone, and after piercing the
INTERNAL CAROTID ARTERY 127
dura mater close by the anterior clinoid process, divides into its terminal
(cerebral) branches. It curves remarkably in different parts of its course,
in the carotid canal and alongside the body of the sphenoid bone it de-
scribes a double curvature resembling the italic letter S placed horizon-
. tally. In the cervical portion no branches are given off; in the petrous,
cavernous and cerebral portions it gives off the following: —
Tympanic (a. carotico- tympanic), — enters the tympanum from the
carotid canal, and anastomoses on the membrana tympani with the
tympanic branch of the internal maxillary and the stylo-mastoid.
Arteries Receptaculi (aa. cavernosae), — numerous small vessels going to
the walls of the sinuses, the Gasserian (semilunar) ganglion and the
pituitary body (hypophysis).
Anterior Meningeal, — a small branch to the dura mater of the anterior
fossa, after passing over the lesser wing of the sphenoid.
Ophthalmic^ — arises from the cavernous portion, enters the orbit through
the optic foramen, terminating at the inner angle of the eye into the
frontal and nasal branches. It gives off the following branches: —
Ocular Group Orbital Group
Art. Centralis Retinae. Lacrimal. Frontal.
Muscular. Supra-orbital. Nasal.
Anterior Ciliary. Posterior Ethmoidal. (the
Short Ciliary. Anterior Ethmoidal. terminal.
Long Ciliary. Internal Palpebral. branches).
•'**' Anterior Cerebral, — joined to its fellow by the Anterior Communicating
Artery, about 2 lines long; then runs alongside its fellow, terminating
by anastomosis with the posterior cerebral arteries, and giving off the
following branches: —
Antero-median Ganglionic or Basal.
Inferior Internal or Medial Frontal.
Ant. Internal or Medial Frontal.
Middle Internal or Medial Frontal.
Posterior Internal or Medial Frontal.
Middle Cerebral (a. cerebri media), — in the fissure of Sylvius; divides
into:—
Antero-lateral Ganglionic or Basal. Ascending Frontal.
Inferior External or Lateral Frontal. Ascending Parietal.
Parieto-temporal.
Posterior Communicating, — anastomoses with the posterior cerebral,
a branch of the basilar, and gives off the: —
128 HUMAN ANATOMY
Postero-median Ganglionic, branches supplying the optic thalami
and the walls of the 3rd ventricle.
Anterior Choroid,—to the hippocampus major, corpus fimbriatum, etc.
and ends in the choroid plexus.
[The vertebral Artery, a branch of the Subclavian, and the Basilar Artery,
formed by the junction of the two vertebrals, may be considered arteries
of the head and neck, but they are most conveniently described as branches
of the Subclavian Artery (see below.)]
THE CIRCLE OF WILLIS
The Circle of Willis (circulus arteriosus) is a remarkable anastomosis
at the base of the brain, formed by the branches of the vertebral and in-
ternal carotid arteries, and giving origin to the 3 trunks which supply
each cerebral hemisphere. Posteriorly, the two Vertebral arteries unite
to form the Basilar, which ends in the two Posterior Cerebral. Anteriorly,
each Internal Carotid gives off the Anterior Cerebral, these latter being
connected by the short Anterior Communicating artery. The circle is
completed by the Posterior Communicating arteries, one on each side,
which connect the posterior cerebral with the internal carotid.
The Circle of Willis gives off, — anteriorly, the anterior cerebral arteries;
antero-laterally, the middle cerebral; and posteriorly, the posterior cerebral;
each artery giving origin to two very different arterial systems: the Cen-
tral Ganglionic System, supplying the central ganglia of the brain; the
Cortical Arterial System, which ramifies the pia mater and supplies the
cortex and subjacent medullary substance. The two systems, though
having a common origin, do not communicate afterwards, and in their
distribution are entirely independent of each other. Hence, between the
parts supplied by each, there is a zone of diminished nutritive activity,
where softening may be especially liable to occur in the brains of old people.
By the Circle of Willis the cerebral circulation is equalized and provision
made for carrying it on if one or more of the branches should be
obliterated.
THE TRIANGLES OF THE NECK
Anterior Triangle of the Neck is bounded, in front, by a line extending
from the chin to the sternum; behind, by the anterior margin of the
sterno-mastoid muscle; its base, directed upward, is formed by the lower
border of the body of the jaw and a line extending from the angle of the
jaw to the mastoid process; its apex is below, at the sternum. It is
crossed by the digastric muscle above and the anterior belly of the omo-
hyoid below, dividing it into 3 smaller triangles, named from below up-
TRIANGLES OF THE NECK I 29
ward the Inferior Carotid, the Superior Carotid, and the Submaxillary
or Submandibular triangles.
Inferior Carotid Triangle, situated below the anterior belly of the omo-
hyoid, contains at it's posterior edge in a common sheath the lower portion
of the common carotid artery, the pneumogastric nerve and the internal
jugular vein, concealed by the sterno-mastoid muscle, also other structures,
which with the former may be summarized as follows: —
Muscles, — the sterno-hyoid and sterno-thyroid, covering the common
carotid artery.
Arteries, — the common carotid and the inferior thyroid.
Veins, — the internal jugular, as described above.
Nerves, — the pneumogastric (n. vagus) recurrent laryngeal, and
sympathetic, also filaments from the loop between the descendens and
communicans hypoglossi.
Other Structures, — the trachea, thyroid gland, and the lower part of the
larynx.
Superior Carotid Triangle, situated above the anterior belly of the omo-
hyoid, contains the upper part of the common carotid artery and its
bifurcation into the internal and external carotid, also other structures,
all summarized as follows: —
Muscles, — parts of the thyro-hyoid, hyo-glossus, inferior and middle con-
strictors of the pharynx.
Vessels, — the common carotid artery, the internal and external carotid
arteries, and the internal jugular vein; the superior thyroid, lingual,
facial (external maxillary), occipital and ascending pharyngeal
branches of the external carotid and the veins accompanying them.
Nerves, — the pneumogastric (n. vagus), spinal accessory (n. accesso-
rius), hypoglossal, descendens hypoglossi, sympathetic, internal and
external laryngeal.
Other Structures, — the upper part of the larynx, and the lower part of the
pharynx.
Sub-mandibular or Sub-maxillary Triangle, immediately below the
body of the jaw, and above the posterior belly of the digastric and the
stylo-hyoid; contains the following: —
Muscles, — the mylo-hyoid, hyo-glossus, stylo-glossus, and stylo-
pharyngeus.
Arteries, — the external and internal carotid; also the facial (external
maxillary), posterior auricular, temporal, internal maxillary, sub-
mental, and mylo-hyoid arteries.
Veins, — the facial and internal jugular,
o
130 HUMAN ANATOMY
Nerves, — the pneumogastric (n. vagus), glosso-pharyngeal, facial, and
mylo-hyoid.
Glands, — the parotid and sub-maxillary (sub-mandibular).
Posterior Triangle of the Neck is bounded, in front by the sterno-
mastoid muscle; behind, by the trapezius; its base corresponds to the
middle third of the clavicle, its apex is at the occiput. It is crossed by
the posterior belly of the omo-hyoid muscle about an inch above the
clavicle, subdividing it into two smaller triangles, the Occipital above, and
the Subclavian below.
Occipital Triangle, the larger division of the posterior triangle of the
neck, above the posterior belly of the omo-hyoid muscle, contains the
following: —
Muscles, — the splenius, levator anguli scapulae (m. levator scapulae),
middle and posterior scaleni.
Vessels, — the transversalis colli artery and vein.
Nerves, — the spinal accessory (n. accessorius), and descending branches
of the cervical plexus.
Glands, — a chain of lymphatic glands.
Subclavian Triangle, the smaller of the divisions of the posterior triangle
of the neck, situated below the posterior belly of the omo-hyoid muscle,
and above the middle third of the clavicle, contains the following: —
Vessels, — the subclavian artery, the Subclavian vein occasionally, the
transversalis colli and suprascapular arteries (a. transversa scapulae),
and veins, the external jugular and transverse cervical veins.
Nerves, — the brachial plexus, descending branches of the cervical plexus.
nerve to the subclavius muscle.
Glands, — a lymphatic gland.
ARTERIES OF THE UPPER EXTREMITY
The Subclavian Artery (Arteria Subclavia) arises on the right side from
the innominate, of the left side from the arch of the aorta, and is divided
into 3 portions by the scalenus anticus muscle, which crosses it just
external to the origin of the thyroid axis, viz. — the parts internal, behind,
and external to that muscle. At the outer border of the ist rib, the sub-
clavian becomes the Axillary Artery. Its upper border is a little above
the clavicle, and it is separated from the subclavian vein by the scalenus
anticus at its origin from the first rib. Its branches are all given from its
first portion, except the Superior Intercostal, which on the right side
arises from the second portion. Its branches are the —
SUBCLAVIAN ARTERY
FIG. 66.
VERTEBRAL (a. vertebralis) (6), — passing up the neck, through the fora-
mina in the transverse processes of six cervical vertebrae, enters the
skull by the foramen magnum, where it joins its fellow to form the
Basilar Artery. Its branches are-
Lateral Spinal Branches.
Muscular Branches.
Posterior Meningeal.
Anterior Spinal.
Posterior Spinal.
Posterior Inferior Cerebellar.
Bulbar.
The Basilar (a. basilaris), — formed
by the junction of the vertebrals,
gives off on each side a transverse,
anterior, and superior cerebellar,
and ends in the two posterior cere-
bral. (See Circle of Willis, pages
151 and 158.)
THYROID Axis (truncus thyreocervi-
calis) (8), — at once divides into the
three following branches.
Inferior Thyroid (a. thyreoidea inferior) (7), — to the thyroid gland,
giving off —
Inferior Laryngeal. CEsophageal Branches.
Tracheal. Muscular. Ascending Cervical (9).
2 Terminal.
Suprascapular (a. transversa scapulae) (12), — to the shoulder- joint
and the dorsum of the scapula, anastomosing there with the pos-
terior and subscapular.
Transversalis Colli (n), — divides beneath the margin of thetrapezius
into —
Superficial Cervical (ramus ascendens).
Posterior Scapular (ramus descendens).
INTERNAL MAMMARY (a. mammaria interna) (13), — arises opposite the
thyroid axis, descends behind the costal cartilages, and ends at the
6th interval, in the musculo-phrenic and superior epigastric, the
latter anastomosing with the deep epigastric branch of the external
iliac. Its branches are the —
132 HUMAN ANATOMY
Comes Nervi Phrenici Paricardiac. Perforating,
(pericardiaco-phrenic), Sternal. Musculo-phrenic.
or Superior Phrenic. Anterior Intercostal. Superior Epigastric.
/ Mediastinal.
'" SUPERIOR INTERCOSTAL (a. intercostalis suprema) (14), — gives off
branches in the intercostal spaces to the posterior spinal muscles
and to the spinal cord. One branch, the —
Profunda Cervids (a. cervicalis profunda) (10), — supplies the mus-
cles of the back of the neck, and anastomoses with the arteria
princeps cervicis (ramus descendens a. occipitalis) of the occipital.
This vessel occasionally arises from the subclavian artery.
1 The Axillary Artery (a. axillaris) (5), the continuation of the subclavian,
commences at the outer border of the first rib, and terminates at the lower
border of the tendon of the teres major muscle, where it becomes the
brachial artery. The pectoralis minor crosses it and marks its division
into three portions, — ist, above; 2nd behind, and 3rd below that muscle.
The brachial plexus is in close relation with the artery, surrounding it on
three sides in the second portion. Its branches are 7 in number as
follows: —
Superior Thoracic (a. thoracalis suprema), — from the first portion;
supplies the pectoral muscles and the walls of the thorax.
Acromial Thoracic (a. thoraco-acromialis), — from the first portion;
divides into the —
Thoracic (pectoral) Branches 2 or 3,— to the serratus magnus (m.
serratus anterior) and pectorals.
Acromial Branches, — to the deltoid muscles.
Descending or Humeral (deltoid), — to the pectoralis major and
deltoid.
Clavicular, — a very small branch, to the subclavius muscle.
Mar Thoracic, — from the second portion; to the glands and theareolar
tissue of the axilla.
Long Thoracic (a. thoracalis lateralis or external mammary), — from
" tlie second portion; to the serratus magnus (m. serratus anterior),
the pectoral muscles and the mammary gland.
Subscapular (a. subscapularis), — from the third portion; to the inferior
angle of the scapula, where it anastomoses with the long thoracic,
the intercostal and the posterior scapular (ramus descendens a.
transversalis Colli) arteries. It gives off small branches to the del-
toid and triceps muscles, and the
Dorsalis Scapulae (a. circumflexa scapulae), — a large branch, to
the subscapular fossa and the axillary border of the scapula.
ARTERIES OF THE UPPER EXTREMITY 133
Posterior Circumflex (a. circumflexa humeri posterior), — from the third
portion; winds around the neck of the humerus to the deltoid muscle
and the shoulder-joint, anastomosing with the anterior circumflex
and other arteries.
Anterior Circumflex (a. circumflexa humeri anterior), — from the third
portion; winds around the neck of the humerus, to the head of that
bone, the deltoid muscle and the shoulder-joint, anastomosing with
the posterior circumflex.
The Brachial Artery (a. Brachialis) is the continuation of the axillary
from the lower margin of the teres major tendon to its bifurcation into the
radial and ulnar, which is usually about half an inch below the bend of the
elbow. The median nerve crosses it from the outside to the inside about
its middle. Above its bifurcation it is crossed diagonally by the bicipital
fascia (lacertus fibrosus). The basilic vein lies on its inner side but sepa-
rated from it in the lower part of the arm by the deep fascia. Its branches
are the —
Superior Profunda (a. profunda brachii), — winds over the arm in the
spiral groove (sulcus radialis), giving off the posterior articular to
the elbow anastomosis, and a branch to anastomose with the recur-
rent branch of the radial, and a nutrient artery to the bone. This
artery supplies the triceps muscle.
Nutrient Branch, — enters the nutrient canal of the humerus.
Inferior Profunda (a. collateralis ulnaris superior), — to the elbow-joint
anastomosis.
- Anastomotica Magna (a. collateralis ulnaris inferior], — anastomoses
with the posterior articular, inferior profunda (superior ulnar col-
lateral) anterior and posterior ulnar recurrent.
Muscular Branches, — to the muscles in the course of the artery.
The Radial Artery (a. radialis) extends from the bifurcation of the
brachial to the deep palmar arch, and gives off the following branches: —
In the Forearm, —
Radial Recurrent, — to the supinators, the brachialis anticus and the
elbow joint, anastomosing with the terminal branches of the superior
profunda (a. profunda brachii).
*'- Muscular Branches, — to the muscles on the radial side of the forearm.
Anterior Carpal (ramus carpeus volaris), — anastomoses with the anterior
carpal of the ulnar artery, forming the Anterior Carpal Arch (rete
carpi volare).
Superficialis Voice, — to the muscles of the thumb.
134 HUMAN ANATOMY
In the Wrist,—
Posterior Carpal (ramus carpeus dorsalis), — anastomoses with the pos-
terior carpal of the ulnar artery forming the Posterior Carpal Arch
(rete carpi dorsale).
Metacarpal, — the first dorsal interosseous branch, divides into two
dorsal digital branches, supplying the adjoining sides of the index
and middle fingers.
7 Dor sales Pollicis 2, — along the sides of the thumb.
Dorsalis Indicis, — along the radial side of the index finger.
Ln the Hand, —
Princeps Pollicis, — along the sides of the palmar aspect of the thumb by
two branches forming an arch.
Radialis Indicis (a. volaris indicis radialis), — along the radial side of
the index finger to anastomose with the collateral digital and the
princeps pollicis, giving a communicating branch to the superficial
palmar arch (arcus volaris superficialis).
Perforating 3, — backward from the deep palmar arch to anastomose
with the dorsal interosseous arteries.
Palmar Interosseous 3 or 4, — from the deep palmar arch, on the inter-
ossei muscles to anastomose with the digital branches of the super-
ficial arch (arcus volaris superficialis).
Palmar Recurrent, — from the deep palmar arch to the carpal joints,
anastomosing with the anterior carpal arch (rete carpi volare).
The Ulnar Artery (a. ulnaris) extends from the bifurcation of the
brachial just below the bend of the elbow along the ulnar border of the
forearm to the wrist. Immediately beyond the pisiform bone it divides
into two branches which enter into the formation of the superficial and
deep palmar (volar) arches. Its branches are as follows: —
In the Forearm, —
Anterior Ulnar Recurrent (a. recurrentes ulnaris anterior), — anastomoses
in front of the inner condyle of the humerus with the anastomotica
magna (inferior ulnar collateral) and the inferior profunda (superior
ulnar collateral).
Posterior Ulnar Recurrent (a. recurrentes ulnaris posterior), — anasto-
moses behind the inner condyle of the humerus with the anastomotica
magna (inferior ulnar collateral), inferior profunda (superior ulnar
collateral) and interosseous recurrent.
Interosseous, — about % inch long, divides into two branches. The
Anterior Interosseous (volar interosseous) gives off the Median
Artery to the median nerve and a Nutrient branch to both bones of the
ARTERIES OF THE FOREARM AND HAND 135
forearm. The Posterior (dorsal) Interosseous gives off near its origin
the Interosseous Recurrent to the elbow-joint anastomosis.
Muscular,—- to the muscles on the ulnar side of the forearm.
In the Wrist, —
Anterior Carpal, (ramus carpeus volaris), — anastomoses with a cor-
responding branch of the radial artery in front of the carpus.
Posterior Carpal (ramus carpeus dorsalis), — anastomoses with a cor-
responding branch of the radial artery forming the posterior carpal
arch (rete carpi dorsale).
In the Hand, —
Deep or Communicating (ramus volaris profunda), — anastomoses with
the termination of the radial artery, completing the deep palmar
arch (arcus volaris profundus).
Superficial Palmar Arch (arcus volaris superficialis), — is the continua-
tion of the trunk of the ulnar artery in the hand.
Digital 4, — given off by the superficial palmar arch (arcus volaris
"superficialis).
- S V THE CARPAL ARCHES
The Anterior Carpal Arch (rete carpi volare) is formed by the anastomo-
sis of the anterior carpal of the radial with the anterior (volar) carpal
of the ulnar artery in front of the wrist. It is joined by branches
from the anterior (volar) interosseous above and by recurrent branches
from the deep palmar (volar) arch below, and gives off branches to
supply the articulations of the wrist and carpus.
The Posterior Carpal Arch (rete carpi dorsale) is formed by the
anastomosis of the posterior (dorsal) carpal of the radial with the posterior
(dorsal) carpal of the ulnar artery. It is joined by the termination of the
anterior (volar) interosseous artery and gives off dorsal interosseous
arteries for the third and fourth interosseous spaces, which divide into
dorsal digital branches which supply the adjacent sides of the middle,
ring and little fingers, and communicate with the digital arteries of the
superficial palmar (volar) arch, and at their origin with the perforating
branches from the deep palmar (volar) arch.
THE PALMAR ARCHES
The Superficial Palmar Arch (arcus volaris superficialis) is formed by
the part of the ulnar artery which lies in the palm of the hand, and is
completed by that artery anastomosing with a branch from theradialis
indicis, at the root of the thumb; sometimes with the superficialis volae
or the princeps pollicis of the radial. It gives off 4 Digital Collateral
136 HUMAN ANATOMY
branches to the sides of the fingers, except the radial side of the index
finger, which with the thumb is supplied from the radial artery.
The Deep Palmar Arch (arcus volaris profundus) is formed by the
palmar portion of the radial artery, and is completed by the anastomosis of
that artery with the deep palmar (communicating) branch of the ulnar.
It lies upon the carpal ends of the metacarpal bones and the interossei
muscles, about ^ inch nearer to the carpus than the superficial palmar
(volar) arch, from which it is separated by the transverse carpal ligament,
the flexor brevis minimi digiti, (m. flexor digiti quinti brevis) the super-
ficial flexor tendons and divisions of the median and ulnar nerves. From
it are given off the radialis indicis, palmar (volar) interosseous, perforating
and palmar (volar) recurrent branches of the radial artery.
ARTERIES OF THE TRUNK
THE DESCENDING AORTA (AORTA DESCENDENS)
The Descending Aorta is divided into two portions, the Thoracic Aorta
(aorta thoracalis) and the Abdominal Aorta (aorta abdominalis), cor-
responding to the two great cavities of the trunk in which they are
situated.
The Thoracic Aorta (aorta thoracalis) commences at the lower border of
the 4th thoracic vertebra on the left of the spine, and descends in the back
part of the posterior mediastinum, terminating at the aortic opening in the
diaphragm directly in front of the lower border of the last thoracic vertebra.
Its branches are —
Pericardia!, — irregular in origin, to the pericardium.
Bronchial, — vary in number and origin; generally one on the right side
and two on the left. They nourish the lungs, bronchial glands and
the oesophagus.
(Esqpjiageal, 4 or 5, — anastomose on the oesophagus with branches of the
inferiorThyroid, phrenic, and gastric arteries.
Posterior Mediastinal, — numerous small vessels supplying the glands and
the areolar tissue in the mediastinum.
Intercostals, — usuallvjj on each side, the two superior intercostal spaces
being supplied by the superior intercostal branch of the subclavian.
They run between the two layers of intercostal muscles, anastomose
with the anterior intercostal branches of the internal mammary, and
each gives off the following branches: —
Posterior or Dorsal, — to the muscles and skin of the back.
Spinal, — to the spinal cord and its membranes.
Collateral Intercostal, — along the upper border of the rib below.
ABDOMINAL AORTA
137
FIG. 67.
.The Abdominal Aorta (aorta abdominalis) begins where the thoracic
aorta ends (see p. 123) and terminates on the body of the 4th lumbar
vertebra, where it divides into the two common iliac arteries. Its branches
are as follows: —
2 Inferior Phrenic (i), — one on each side, but usually only one arises
from the aorta, the other springing from either the coeliac axis or the
renal artery. They go to the under surface of the diaphragm, where
each a rtery divides into two
branches, an external and an in-
ternal, the former to the side the
latter to the front of the thorax
and the diaphragm.
CCELIAC Axis (a. coeliaca) (2), arises
from the aorta, close to the margin
of the opening in the diaphragm,
runs forward for half an inch, and
divides into the Left Gastric, He-
patic, and Splenic (a. lienalis) arte-
ries, occasionally giving off one of
the phrenics. The —
Js'ft Gastric (a. gastrica sinistra) (3),
— supplies the stomach along its
lesser curvature, anastomosing
with the aortic cesophageal, splenic
(a lienalis), and hepatic branches.
JIe£atic (a. hepatica) (4), — forms the
lower boundary of the foramen of
Winslow (foramen epiploicum),
passes upward to the transverse
fissure (porta hepatis) of the liver
where it divides into two branches,
right and left, supplying the corre-
sponding lobes of that organ. Its
branches are the —
Pyloric (a. gastrica dextra), — to
the pyloric end of the stomach
and along the lesser curvature
of that viscus.
Gastro-duodenalis, — giving off the Gastro-epiploica Dextra along
the greater curvature of the stomach, and the Pancreatico-duo-
138 HUMAN ANATOMY
denalis Superior to the contiguous margins of the duodenum and
pancreas.
Right Hepatic, — to the right lobe of the liver, giving off the Cystic
Artery to the gall-bladder.
Left Hepatic, — to the left lobe of the liver.
Splenic (a. lienalis) (5), — the largest, branch of the cceliac axis, passes by
^""a very tortuous course to the spleen, giving off the following: —
Pancreaticae Parvae. Gastric (VasaBrevia) (a.a. gastricae breves)
to the stomach.
Pancreatica Magna. Gastro-epiploica Sinistra, to the stomach.
Terminal Branches, enter the hilum of the spleen.
Superior Mewnteric (a. mesenterica superior) (9), — supplies the small
intestine, caecum, ascending and transverse colon. Arising about
% inch below the cceliac axis it arches forward, downward, and to
the left, giving off the —
Inferior Pancreatico-duodenal. Ileo-colic.
Vasa Intestini Tenuis (aa. in- Colica Dextra and Media.
testinales), 12 to 15.
V0" Supra-renal (a. supra-renalis media) (6), — arise one on each side,
opposite the origin of the superior mesenteric, passing to the supra-
renal capsules.
2 Renal (aa. renales) (7), — one from each side, just below the preceding,
pass to the kidney, at its hilum having the middle place between the
ureter behind and the renal vein in front. U. A. V. (you 'ave!) •
2 Spermatic (aa. spermaticae internae) (10), — one on each side, in the male
through the inguinal canal to the testes; in the female it is called
Ovarian (a. ovarica), going to the ovaries, uterus and skin of the
labia and groins.
Inferior Mesenteric (a mesenterica inferior) (n), — supplies the descend-
ing colon, sigmoid flexure, and most of the rectum, giving off the
following branches: —
Colica Sinistra. Sigmoid (aa. sig- Superior Hemorrhoidal.
moidece).
Lumbar (aa. lumbales) (8), — usually 4 on each side, analogous to the
intercostals. They each divide into two branches, the —
Dorsal, giving off a spinal branch. Abdominal.
Middle Sacral (a. sacralis media) (12), — arises just at the bifurcation of
/
THE ILIAC ARTERIES 139
the aorta; it descends along the last lumbar vertebra and the front
of the sacrum to the upper part of the coccyx, giving off numerous
branches on each side to anastomose with the lateral sacral arteries.
It terminates in a minute branch which goes to the coccygeal gland
(Luschka), and sends off branches to the rectum.
THE ILIAC ARTERIES (ARTERLE ILIAC.E)
The Common Iliac Arteries (aa. iliacae communes) extend from the
bifurcation of the aorta at the 4th lumbar vertebra to the lumbo-sacral
articulation, where each divides into the External Iliac (15) and the
Internal Iliac (a. hypogastrica) (14); the former supplying the lower
extremity, the latter going to the viscera and walls of the pelvis. The
common iliac arteries are about 2 inches in length, the right being a little
longer than the left, and each is crossed by the ureter, just before its
bifurcation.
The Internal Iliac (arteria hypogastrica) (14) is about i% inches long,
extending from the lumbo-sacral articulation to the great sacro-sciatic
notch, where it divides into an anterior and a posterior trunk. From the
Anterior Trunk are given off, from above downward, the —
Superior Vesical (a. vesicalis superior), — the remaining previous part,
of the fcEtal hypogastric artery. It sends branches to the bladder
the vas deferens and the ureter; and one, the Middle Vesical, to the
base of the bladder.
Obturator (a. obturatoria), — through the canal in the obturator mem-
brane to the thigh, where it divides into an internal and external
branch. Within the pelvis it gives off an iliac, a vesical, and a pubic
branch. In one out of every 3^ cases this artery arises from the
deep epigastric (a. epigastrica inferior), in 2 out of every 3 from the
internal iliac (a. hypogastrica), in i out of 7^ by two roots from both
vessels and in about the same proportion from the external iliac.
Inferior Vesical (a. vesicalis inferior), — to the bladder, prostrate gland,
and vesiculae seminales. In the female this artery is called the
Vaginal (a. vaginalis).
Middle Hemorrhoidal (a. haemorrhoidalis medialis), — to the anus and
parts outside the rectum.
Uterine (a. uterina), — in the female, anastomosing with a branch
(ramus ovarii) from the ovarian. It gives off cervical branches to
the cervix uteri and the azygos arteries of the vagina.
Internal Pudic (a. pudenda interna), — the smaller of the terminal
branches of the anterior trunk, supplies the external generative
140 HUMAN ANATOMY
organs. Its muscular branches in the pelvis are numerous and small;
in the perineum they are the —
Inferior Hemorrhoidal (a. Artery of the Bulb (a. bulbi
haemorrhoidalis inferior). urethrae).
Superficial Perineal (a. Urethral (a. urethralis).
perinei). Artery of the Corpus Cavernosum
Transverse Perineal (a. (a. profunda penis).
trans versa perinei). Dorsal Artery of the Penis (a dor-
salis penis).
Sciatic (a. glutaea), — the other terminal branch, supplies the muscles on
the back of the pelvis. Its branches are the —
Muscular (internal), rami musculares.
Hemorrhoidal Brs.
Vesical Branches.
Coccygeal.
Cutaneous.
Comes Nervi Ischiadici, (a. comitans n. ischiadici).
Muscular (ext.), (rami musculares).
Anastomotic.
Articular.
THE POSTERIOR TRUNK gives off the following: —
Ilio-lumbar (a. ilio-lumbalis), — dividing into a lumbar and an ilica
branch.
Lateral Sacral (arteriae sacrales laterales), — superior and inferior on each
side.
Gluteal (a. glutaea superior), — the continuation of the posterior trunk,
divides into a superficial and a deep branch, to the glutei muscles,
the skin over the sacrum, and the hip-joint. Before dividing it gives
a nutrient branch to the ilium, and some muscular branches.
The External Iliac (a. iliaca externa) extends to beneath the centre of
Poupart's ligament (l.inguinale), where it enters the thigh and becomes the
Femoral Artery; lying between the femoral vein on the inside and the
anterior crural nerve (n. femoralis) on the outside — V.A.N. Its branches
are small muscular and glandular, and the — -
Deep Epigastric (a. epigastrica inferior), — which arises a few lines above
Poupart's inguinal ligament, passes between the peritoneum and the
transversalis fascia, to the sheath of the rectus which it enters
and ascends behind that muscle, to anastomose by numerous branches
with the terminal branches of the internal mammary and inferior
intercostal. It gives off the —
THE FEMORAL ARTERY 141
Cremasteric (a. spermaticainthe male; a. ligament! teres uteri in
the female).
Pubic. Muscular Branches (rami musculares).
Deep Circumflex Iliac (a. circumflexa ilium profunda), — arises opposite
to the epigastric, passes along the crest of the ilium to about its
middle, where it pierces the transversalis and runs backward between
that muscle and the internal oblique to anastomose with the ilio-
lumbar, gluteal (a. glutaea superior), lumbar and epigastric ateries.
^'5*4 ARTERIES OF THE LOWER EXTREMITY
The Femoral Artery (arteria femoralis) extends from Poupart's liga-
ment (1. inguinale) to the opening in the adductor magnus, where it
becomes the popliteal artery. Its course corresponds to a line drawn
from a point midway between the anterior superior spine of the ilium and
the spine of pubis, to the inner side of the inner condyle of the femur.
It lies in a strong fibrous sheath with the femoral vein, but divided from
the latter by a fibrous partition. It may be divided into two portions,
the Common Femoral and the Superficial Femoral, for convenient de-
scription, as follows: —
The Common Femoral Artery, — about 2 inches long, is very superficial,
rests on the inner margin of the psoas muscle, which separates it from
the capsular ligament of the hip-joint, and is covered by the skin,
superficial fascia, superficial inguinal glands, iliac portion of the fascia
lata, and the anterior part of the sheath of the vessels.
The Superficial Femoral Artery, — is only superficial in Scarpa's triangle
(femoral trigone), being deeper in Hunter's canal (adductor canal).
It lies above on the femoral vein and the profunda artery and vein;
below, on the adductor longus and adductor magnus muscles. The
internal saphenous nerve crosses it from without inward.
Branches of the Femoral Artery, are as follows: —
Superficial Epigastric (a. epigastrica superficialis) (c), — through the
saphenous opening (fossa ovalis) to ascend on the abdomen, giving
off branches to the skin, the superficial fascia and the superficial
inguinal glands.
Superficial Circumflex Iliac (a. circumflexa ilium superficialis) (;'), — to
the crest of the ilium, supplying the skin of the groin, the superficial
fascia, and the superficial inguinal glands.
Superficial External Pudic (a. pudenda externa superficialis) (d),—
through the saphenous opening (fossa ovalis) to the skin of the
abdomen, the penis and the scrotum (and the labium in the female).
142
HUMAN ANATOMY
FIG. 68.
Deep External Pudic (a. pundenda externa profunda) (d), to the skin of
the scrotum and perinseum (and the labium in the female).
Muscular (rami musculares).
Profunda Femoris (Deep Femoral Artery) (e), — arises posteriorly about
i or 2 inches below Poupart's (inguinal) ligament, and descends to
the lower third of the back of the thigh, giving off the following
branches: —
Ext. Circumflex (a. circumflexa femoris
lateralis) (g).
Int. Circumflex (a. circumflexa femoris
medialis) (/).
3 Perforating (aa. perforantes) (h).
Terminal or 4th perforating.
Muscular Branches (rami musculares) (&), —
to the sartorius and vastus internus.
Anastomotica Magna (a. genu suprema), —
arises from the femoral in Hunter's (ad-
ductor) canal and divides into a super-
ficial and a deep branch, the latter anas-
tomosing around the knee-joint with the
superior external and internal articular
arteries, and the recurrent branch of the
aniecior tibial.
Scarpa's Triangle (Trigonum Femorale) is
a triangular space in the thigh which cor-
responds to the depression seen immediately
below the fold of the groin. Its apex is down-
ward, its base formed by Poupart's (inguinal)
ligament, and its sides externally by the sar-
torious, internally by the adductor longus.
Its floor is formed by the iliacus, psoas, pec-
tineus and adductor longus muscles, from
without inward. It is bisected vertically by
the femoral vessels, which extend from the middle of its base to its apex.
It also contains the anterior crural nerve (n. femoralis) external to the
vessels, together with lymphatic vessels and glands and some fat.
Hunter's Canal (Canalis Adductorius) is the interval between the ad-
ductor magnus and the vastus internus (m. vastus medialis) in the middle
third of the thigh, extending from the apex of Scarpa's triangle to the
femoral opening in the adductor magnus muscle, and lying beneath the
ARTERIES OF THE LEG 143
sartorius. It contains the femoral vessels in their sheath, the vein lying
behind and to the outer side of the artery; also the long saphenous nerve, at
first external to and then in front of the vessels.
The Popliteal Artery (a. Poplitea), the continuation of the femoral,
extends from the opening in the adductor magnus, passing behind the
knee-joint, to the lower border of the popliteus muscle, where it divides into
the Anterior and Posterior Tibial Arteries. It is crossed by the popliteal
vein and the internal popliteal nerve (n. tibialis), and gives off the follow-
ing-named branches, which are distributed around the knee-joint in a free
anastomosis; except the Azygos Articular, which pierces the posterior
ligament of the joint to reach the internal ligaments and the synovial
membrane. Branches are named as follows: —
i Superior Muscular Branches.
Inferior Muscular, or Sural.
Cutaneous Branches.
Superior Articular, internal (a. genu superior medialis) and external
(a. genu superior lateralis).
Azygos Articular (a. genu media).
Inferior Articular, internal (a. genu inferior medialis) and external
(a. genu inferior lateralis).
The Anterior Tibial Artery (a. Tibialis anterior) extends from the
bifurcation of the popliteal to the front of the ankle-joint, where it be-
comes the Dorsal is Pedis. It passes between the two heads of the tibialis
posticus (m. tibialis posterior) over the upper edge of the interosseous
membrane and along its anterior surface, resting on the tibia for its lower
third. It is accompanied by the anterior tibial nerve (n. peronaeus pro-
fundus) close to it externally, and is crossed below by the tendon of the
extensor proprius hallucis. Its branches are named the —
Posterior Recurrent Tibial (a. recurrens tibialis posterior).
Superior Fibular.
Anterior Recurrent Tibial (a. recurrens tibialis anterior).
^ Muscular (rami musculares).
Internal Malleolar (a. malleolaris anterior medialis).
External Malleolar (a. malleolaris anterior lateralis).
The Dorsalis Pedis Artery, the continuation of the anterior tibial, ex-
tends from the front of the ankle-joint along the tibial side of the foot, to
the back part of the ist intermetatarsal space, where it terminates in the
Dorsalis Hallucis and the Communicating (ramus plantaris profundus).
The anterior tibial nerve lies close to its outer side. Its branches are as
follows: —
144 HUMAN ANATOMY
* Tarsal (a. tarsalis lateralis), — passing outward along the tarsus.
-•) Metatarsal (a. arcuata), — giving off 3 Interosseous (aa. metatarseae
dorsales), and the 7 Digital branched (aa. digitales dorsales).
Dorsalis Hallucis, — to the great toe and the inner side of the second toe
by its 3 digital branches.
; Communicating (ramus plantaris profundus), — dips down into the sole
of the foot in the ist interosseous space of the metatarsus, to inosculate
with the external plantar, completing the plantar arch. Its plantar
digital branch, the arteria magna hallucis, supplies the inner side
of the great toe and the adjacent sides of the great and second toes,
on their plantar surfaces.
The Posterior Tibial Artery (A. Tibialis Posterior) is a large vessel,
extending from the bifurcation of the popliteal along the back of the tibia
to the fossa below the inner malleolus, where it divides into the Internal
(medial) and External (lateral) Plantar. The posterior tibial nerve crosses
it a short way below its origin and then lies near its outer side for the rest
of its course. Its branches are as follows: —
/ Peroneal (a. peronaea) , — along the fibular side, giving off the following : —
Muscular (rami musculares).
Nutrient of the fibula (a. nutrica fibulae).
Anterior Peroneal (ramus perforans).
Communicating (ramus communicans).
Posterior Peroneal.
External Calcanean (ramus calcaneus lateralis).
Nutrient of the Tibia (a. nutrica tibiae), — the largest nutrient artery of
bone in the body.
Muscular Branches (rami musculares), — to the posterior muscles of the
leg.
' Communicating (ramus communicans), — to join a similar branch of the
peroneal artery.
Internal Calcanean Branches (rami calcanei mediales), — to the heel and
sole of the foot.
Internal Malleolar (a. malleolaris posterior medialis).
The Internal Plantar Artery (a. plantaris medialis), the smallest of the
terminal branches of the posterior tibial, passes along the inner side of the
foot and great toe.
The External Plantar Artery (a. plantaris lateralis) sweeps across the
plantar aspect of the foot in a curve, the convexity of which is directed
outward and forward; and at the interval between the bases of the ist
and 2d metatarsal bones it inosculates with the communicating branch
IMPORTANT ARTERIAL ANASTOMOSES 145
frortl the dorsalis pedis, completing the Plantar Arch (arcus plantaris")
or the Stirrup Anastomosis. It gives off numerous muscular branches,
and the —
Posterior Perforating (rami perforantes posteriores), — 3 small branches
which ascend through the 3 outer interosseous spaces between the
heads of the dorsal interossei muscles.
Digital Branches (aa. digitales plantares), 4, — supplying the sides of the
3 outer toes and the outer side of the 2d toe; its inner side, together
with the great toe, being supplied by the communicating branch of
the dorsalis pedis.
ARTERIAL ANASTOMOSES
The Anastomosis around the Shoulder- joint is formed by the following
8 arteries, viz.—
Posterior Scapular (ramus descendens a. trans versa colli).
Subscapular (a. circumflexa scapulae) br. of axillary.
Dorsalis Scapula (a. circumflexa scapulae) br. of subscapular.
Infraspinous, br. of dorsalis scapulae.
S upr as ca pular (a. transversa scapulae), br. of thyroid axis.
Ant. Circumflex (a. circumflexa humeri anterior), br. of axillary.
Post. Circumflex (a. circumflexa humeri posterior), br. of axillary.
Acromial, br. of acromial thoracic.
The Anastomosis around the Elbow-joint is formed by the —
Superior Profunda, (a. profunda brachii), br. of brachial.
Posterior Articular, br. of superior profunda.
Radial Recurrent, br. of radial.
Interosseous Recurrent, br. of posterior interosseous.
Inferior Profunda (a. collateralis ulnaris superior), br. of brachial.
Anastomotica Magna (a. collateralis ulnaris inferior), br. of brachial.
A nterior Ulnar Recurrent, br. of ulnar.
Posterior Ulnar Recurrent, br. of ulnar.
The Anastomotica Magna is the vessel most engaged in this anastomosis,
the only part in which it is not employed being that in front of the ex-
ternal condyle of the humerus.
The Anastomosis around the Hip-joint is formed by the —
Gluteal (superior gluteal), Ilio-lumbar, and Circumflex Iliac, with the Ex-
ternal Circumflex.
Obturator and Sciatic (inferior gluteal), with the Internal Circumflex.
Comes Nervi Ischiadici, with the Perforating branches of the Profunda.
10
146 HUMAN ANATOMY
The Arteries Anastomosing around the Knee-joint are the —
Descending, br. of ext. circumflex. Sup. Int. Articular, br. of popliteal.
Anastomotica Magna (a. genu su- Inf. Ext. Articular, br. of popliteal.
prema), br. of femoral. Inf. Int. Articular, br. of popliteal.
Inferior Perforating, br. of profunda. Ant. Recurent, br. of anterior tibial.
Superior Ext. Articular, br. of popliteal.
This anastomosis is sometimes called the deep plexus of the Circum-
patellar Anastomosis; a superficial arterial plexus being situated between
the fascia and skin around the patella.
.The Crucial Anastomosis is formed behind the junction of the neck of
the femur with the great trochanter, between the adductor magnus and
quadratus femoris muscles, by the anastomosis of the following-named
arteries: —
Transverse branch of Ext. Circumflex (from profunda), externally.
Terminal branch of Int. Circumflex (from profunda), internally.
First Perforating branch of the Profunda Femoris, below.
Anastomotic branch of the Sciatic (from. int. iliac), above.
The Longest Anastomosis in the Body is that between the subclavian
and the external iliac by the anastomosis of the Superior Epigastric, br.
of the internal mammary, with the Deep Epigastric, br. of the external
iliac.
[The circle of Willis has been described on page 128; the palmar and
plantar arches on pages 135 and 145 respectively; and the anastomosis
of the membrana tympani on page 298.]
The Collateral Circulation, after Ligature of the Common Carotid
Artery, is established by the free communication existing between the
carotid arteries of opposite sides both within and without the cranium,
and by enlargement of the branches of the subclavian artery on the ligated
side. Outside the skull the principal communication takes place by
the following anastomoses: —
Superior Thyroid, br. of the external carotid, with the Inferior Thyroid,
br. of the thyroid axis (from the subclavian).
Arteria Princeps Cervicis, br. of the occipital (from the external carotid),
with the Vertebral, br. of the subclavian, and the Profunda Cervicis,
br. of the superior intercostal (from the subclavian).
After Ligature of the Subclavian in its first part, the Collateral Circu-
lation is carried on by the following anastomoses: — i, that between the
Superior and Inferior Thyroid arteries (see above); 2, that between the two
Vertebrals; 3, that between the Internal Mammary, the Deep Epigastric
and the Aortic Intercostals; 4, the Superior Intercostal with the Aortic
ARTERIAL SYSTEM TABULATED 147
Intercoslals; 5, the Profunda Cervicis with the Princeps Cervicis; 6, the
Scapular branches of the thyroid axis with branches of the Axillary; 7,
the Thoracic branches of the Axillary with the Aortic Intercostals.
TABLES AND PLATES
OF THE
ARTERIAL SYSTEM
NOTE. — The arteries in the following plates should be colored red, by painting
them over with ordinary crimson ink, or water-color paint, using a fine camel's-
hair brush for the purpose.
Figures in parentheses in these tables refer to the number of another table, thus —
Ext. Carotid (3) means Table No. 3 of the External Carotid Artery.
THE ARTERIAL SYSTEM
i. .1 Numerous branches through-
Pulmonary Artery. ^ p^Zv' ART Pat 3 f°Ut "» PU'm°nary
(Plate i.) 3) J carrying venous blood.
HUMAN ANATOMY
THE ARTERIAL SYSTEM.— Continued
R. CORONARY 1
2.
Arch of Aorta.
(Plate i.)
L. CORONARY J
INNOMINATE
to the muscular tissue of the heart.
R. COMMON CAROTID
R. SUBCLAVIAN
[ becomes Axillary
(8)
Ext. Carotid (3).
Int. Carotid (4).
Vertebral (5).
Thyroid Axis (6).
Int. Mammary (7).
Sup. Intercostal.
L. COMMON CAROTID, . . Same as R. Common Carotid.
L. SUBCLAVIAN, . . Same as R., continuing as Axillary (8).
External Carotid.
(Plate i.)
Superior
Thyroid.
Lingual
Submental
Facial or Ex-
ternal Max-
illary.
Muscular and Glandular branches.
Hyoid, along lower border of os hyoides.
Superf. Descending, crosses Com. Carotid.
Sup. Laryngeal, to larynx and epiglottis.
Crico-thyroid, crosses Crico-thyroid membrane.
( Hyoid, along upper border of bone.
I Dorsalis Linguae, to tongue, tonsil, palate, etc.
I Sublingual, to gland, mouth, gums.
( Ranine, under surface of tongue, to tip.
Inf. (Asc.) Palatine, to soft palate and tonsil.
Tonsillar, to tonsil and root of tongue.
Submandibular, to gland, skin, muscles.
Superf. Br. anas. inf. labial.
Deep Br. to the lip.
Muscular, to pterygoid, masseter, buccinator.
Inf. Labial, anas, with br. of ?th and sth N.
Inf. Coronary or labial, anas, with br. of inf.
dental art.
Sup. Coronary, f Art. of Septum Nasi.
or labial. \ Br. to ala of nose.
Lateralis Nasi, to ala and dorsum of nose.
A ngular, termination of facial trunk.
Muscular, to digastric, stylo-hyoid, etc.
Sterno-mastoid, to that muscle.
Auricular, to back part of concha.
Occipital •( Inf. Meningeal, to dura mater in post, fossa.
Superf. Br. anas, superf.
cervical, of trans, colli.
Princeps Cervicis \ Deep Br. anas, vertebral,
and deep cerv. br of
sup. intercostal.
ARTERIES OF THE HEAD AND NECK.
Plate
' i
GOHTINUED
Potter, del..
T4Q
150
HUMAN ANATOMY
THE ARTERIAL SYSTEM.— Continued
Post. A uricular. .
Branches (small), to muscles and glands.
Stylo-mastoid, to tympanum, mastoid cells, etc.
Auricular, to cartilage of ear.
Mastoid, to scalp above ear.
j Prevertebral, brs. to muscles and nerves.
Ascending I Tympanic, to inner wall of tympanum.
Pharyngeal. ] Meningeal Branches, to dura mater.
[ Pharyngeal Branches, 3 or 4 in number.
3-
Superficial
External
Temporal.
Carotid.
(Contin-
ued.)
INTERNAL
i.
MAXILLARY.
Divisions:
i. Maxillary.
2. Pterygoid.
3. Spheno-
maxillary.
Transverse Facial, lies on the masseter.
Anterior Auricular Branches, to pinna, etc.
Middle Temporal, supplies that muscle.
Anterior Temporal, to the forehead.
Posterior Temporal, along side of head.
_, . / to memb. tympani, anas, with Stylo-
j. ympanic\ . , ,. __. -.
( mastoid and Vidian arteries.
Deep Auricular, to outer surface of the mem-
brana tympani.
Mid. Meningeal, to dura and cranial bones.
Small or Accessory Meningeal, to dura and Gas-
serian gang.
Inferior Dental L*n*Ual' to m'm' of mouth"
I Mylo-hyoid, in that groove.
M^Tl l Tern"nal Brs-
Mandibular
j Deep Temporal, 2, under temporal muscle.
I Pterygoid Brs., to pterygoid muscles.
I Masseteric to deep surface of masseter.
( Buccal, a small br. to buccinator.
A Iveolar
Dental, to molars, bicuspids.
Branches, to antrum, gums, etc.
(several brs. to the orbit.
Ant. Dental, to front teeth, an-
trum.
Post. (Desc.) Palatine, to palate, glands, etc.
Vidian, to Eustachian tube and pharynx.
Ptery go- palatine, to Eustach. tube and pharynx.
Artery of Septum, to septum.
External Branches 3, to the
nares, antrum, ethmoid and
sphenoid cells.
Spheno- palatine
ARTERIAL SYSTEM TABULATED
THE ARTERIAL SYSTEM.— Continued
Tympanic, to tympanum by foramen in carotid canal.
Arteria Receptaculi (several), in cavernous sinus.
Ant. Meningeal, to dura mater of ant. fossa.
r Lacrimal, to that gland, lid, etc.
Supraorbital, the largest sub-branch.
. , ,/ Meningeal, to dura.
Post-Eihmotdal \NasalBrs., to nose.
i. •
Ant. Ethmoidal, has same branches.
Sup. Palpebral, arch on margin of lid.
OPHTHALMIC.
Inf. Palpebral, margin of lower lid.
Groups:
Frontal, to muscles, skin 1
i. Orbital.
/ Transverse, [Terminal Branches.
4.
2. Ocular.
* \DorsolisNasi. J
Internal
(Plate 4.
Carotid.
Pig. 2.)
Art. Centralis Retina, to the retina.
(Plate i.)
( Ant. Ciliary, to the iris.
Muscular \ Superior, to ocular muscles.
2. '
[ Inferior, to ocular muscles.
Short Ciliary, 6 to 12, around optic n.
Long Ciliary 2, to circles on iris.
A nlerior Cerebral
( Ant. Communicating, 2 lines long.
' ' \ Ganglionic and Frontal branches.
Middle Cerebral
/ Ganglionic, Frontal, Parietal, and Parieto-
\ temporal branches.
Posterior Communicating,
anas, with Post. Cerebral of Basilar, to
form the Circle of Willis.
Anterior Choroid, to the choroid plexus, etc.
BASILAR
Post. Cerebral Post. Commun.
THE CIRCLE OF WILLIS
I^TERNAL
CAROTID.
Ant. Cerebral
ral \
Post. Cerebral Post. Commun.
Ant' Cerebral
Ant.
Commun.
152
HUMAN ANATOMY
THE ARTERIAL SYSTEM.— Continued
s.
VERTEBRAL
(Plate i.)
Lateral Spinal
Anterior Spinal
Br. to spinal cord and membranes.
Br. to bodies of Vertebras posteriorly.
Muscular Branches, to deep cervical muscles.
Post. Meningeal, ramify between dura mater and skull.
joins its fellow to form Ant. Median Artery of the
spinal cord.
Posterior Spinal, to spinal cord and membranes, laterally.
/ Internal \ to cerebellum, and choroid plexus
Post. Inf. Cerebellar s _ , > ,, .v-ir^-i
( External J of the 4th Ventricle.
Bulbar, minute branches to the medulla oblongata.
/ to Pons Varolii, etc.
Transverse s T . ,. , .
( Int. Auditory, to that canal.
, „ /to the cerebellum, anas, with post.
Ant. Inf. Cerebellar \ . , ... f ,, . , .
( inf. cerebellar of Vertebral.
Superior Cerebellar, to pia mater, pineal gland, etc.
Post. Choroid, to choroid plexus
Ganglionic, to post, lobes.
Posterior Cerebral •{ Ant. Temporal,
•n m I terminal
Post. Temporal, }• ,
_ . . . branches.
Occipital,
Inf. Laryngeal, to post, muscles of larynx.
Tracheal Brs. to trachea, anas. Bronchial.
(Esophageal Brs. to oesophagus.
Ascending Cervical, to muscles, spinal cord.
Muscular, to muscles of hyoid bone and of the
pharynx.
Superficial Cervical, beneath Trapezius.
Posterior Scapular, along post, border.
Supra-acromial, anas. Acromial Thoracic.
Supra-scapular. . . . I Supra-sternal, to skin of the chest.
1 Muscular, to sterno-mastoid, etc.
I Nutrient, to the clavicle.
6.
THYROID
Axis.
(Plate i.)
Inferior Thyroid.
Transversalis Colli.
Comes Nervi Phrenici (Superior Phrenic), to Diaphragm.
Mediastinal Brs. to tissue and glands, ant. mediastinum.
Pericardiac Brs. to upper part of pericardium.
Sternal Brs. to sternum and Triangularis sterni.
INTERNAL Anterior Intercostals, to 5 or 6 upper intercostal spaces.
MAMMARY. Perforating, to Pectoralis major, mammary gland, etc.
(Plate i.) •»*..„,..!„ ^i.^a^;^ / Ant. Intercostals, to lower intercostal spaces.
Brs. to lower pericardium, Diaphragm, etc.
f anas, with deep Epigastric of Ext. Iliac.
\ supplies abdominal muscles and skin.
Musculo-phrenic
Superior Epigastric
ARTERIAL SYSTEM TABULATED
Axillary.
(Plate 2.)
i from ist part,
i " 2d "
3 " 3d "
THE ARTERIAL SYSTEM.— Continued
j Superior Thoracic, to Pectoral muscles and wall of thorax.
( Brs. to Pectorals and Deltoid.
[ Acromio Thoracic -| Descending, to both these muscles.
[ Clavicular, to the Subclavius.
( Alar Thoracic, to glands of axilla.
\ Long Thoracic, to Serratus, Pectorals and glands.
Subscapular
A nterior Circumflex
[ Subscapular.
Dorsalis Scapulce \ Infra-spinous.
{ Median.
Main trunk to inf. angle of the scapula.
f around neck of humerus, to Deltoid.
1 Br. to shoulder-joint.
Posterior Circumflex
\ around neck of humerus, to Deltoid
\ muscle and shoulder-joint.
Becomes BRACHIAL (10), at lower margin of tendon of the Teres major
muscle.
(Post. Articular, to elbow-joint anastomosis
and inner side of arm.
Main trunk, in spiral groove of the hu,
merus, to Deltoid, Triceps, etc.
9. Nutrient, to nutrient canal of the humerus.
Brachial. • Inferior Profunda (sup. uln. collat.) to the elbow-joint anastomosis.
(Plate 2.) Anastomotica Magna (inf. uln. collat.), transversely inward on
Brachialis anticus muscles to the elbow, where it anastomoses
with several arteries.
Muscular, 3 or 4, to muscles in course of artery.
Bifurcates into RADIAL (10) and ULNAR (n).
( Radial Recurrent, anas, branches of Sup. profunda.
J Muscular Brs. to muscles on radial side of arm.
Ant. Carpal, to wrist-joints, anas. Ant. Carpal of Ulnar.
Superficialis Voice, to muscles of the thumb.
Post. Carpal
to wrist-joints, anas. Post. Carpal of Ulnar.
Dorsal Interosseous, for 3d and 4th spaces.
Metacarpal, is the First Dorsal Interosseous Branch.
Dor sales Pollicis 2, laterally on dorsum of thumb.
Dorsalis Indicts, on radial side of index dorsum.
10.
Radial.
(Plate 2.) 2.
1. In forearm.
2. In wrist.
3. In hand.
Princeps Pollicis, 2 Brs. forming arch on last phalanx.
Radialis Indicts, along radial side of index ringer.
Perforating 3 between heads of last Dorsal Interossei.
/ 3 or 4 along Interossei muscles, given
Palmar Interossea{ - . „ %> 1
\ off by Deep Palmar Arch.
Palmar Recurrent, to the carpal articulations.
Forms DEEP PALMAR ARCH in the hand, completed by inosculation with
the Deep Palmar (Communicating) from the Ulnar Artery.
154
HUMAN ANATOMY
THE ARTERIAL SYSTEM.— Continued
Anterior Ulnar Recurrent, ascends in front of inner condyle
Posterior Ulnar Recurrent, ascends behind inner condyle.
pierces Interosseous mem-
brane, descending to back
of wrist.
Anterior • Muscular Branches.
Interosseous Nutrient, of both bones.
Br. on Pronator quadratus.
Interosseous \ [ Median, along median n.
11.
Ulnar.
(Plate 2.)
1. In forearm.
2. In wrist.
3. In hand.
3.
Posterior
Interosseous
to back of wrist.
Interosseous Recurrent, to
elbow-joint anastomosis.
Muscular, to muscles on ulnar side of arm.
Anterior Carpal, to joints, anas. Carpal of Radial.
| to joints of wrist, anas. Carpal of Radial.
Posterior Carpal j forming the Post. Carpal Arch.
[ Metacarpal, to little finger.
!anas. with termination of Radial
Artery, completing the Deep
Palmar Arch.
from convexity of Superf. Palmar Arch, to the
sides of the fingers, except the radial side of
the index finger and thumb (supplied from
the radial).
Digital 4
Forms SUPERFICIAL PALMAR ARCH in palm of hand, by inosculating with
a branch from the Radialis Indicis of the Radial Artery.
Pericardiac Branches, distributed to the pericardium.
Bronchial Arteries 3 nutrient vessels of the lungs.
12. (Esophageal, 4 or 5, anas. brs. Inf. Thyroid, Phrenic, Gastric.
Thoracic ^ Posterior Mediastinal, (several) to glands, etc., in mediastinum.
Aorta. I Posterior (Dorsal), to muscles of back.
(Plate 3). Intercostals. I Spinal, to the spinal cord and its membranes.
1 8. | Collateral Intercostal, along upper border of the
1 next rib below.
ARTERIES OF THE
UPPER EXTREMITY.
\
Potter del
156
HUMAN ANATOMY
THE ARTERIAL SYSTEM.— Continued
l Internal, to front of thorax and Diaphragm.
Phrenic | External, to side of thorax.
to cardiac orifice of stomach, cardiac end.
- rin rfW f t
then along lesser curvature to pylorus,
where it anas, with Pyloric Br. of Hepatic
Art.
Pyloric, to pylorus, anas. Gastric Art.
f Gastro-epiploica
\ Dextra
Gastro-duodenalis < D * ,
Pancreatico-duo-
CcELIAC
{ denalis Superior.
Axis.
Hepatic •
TT ) to right lobe.
Right Hepatic, < -,
\ Cystic, to gall-bladder.
Left Hepatic, to left lobe of liver.
Pancreaticce Parva \
> to the pancreas.
Pancreatic Magna )
Splenic
Gastric Vasa Brevia, 5 to 7, to the greater
or
curvature of stomach.
Lienal
Gastro-epiploica Sinistra, along the greater
curvature, from left to right.
Terminal Brs. enter hilum of Spleen.
13-
Inferior Pancreatico-duodenal, to those organs.
Abdominal
Vasa Intestini Tenuis 12 to 15, form arches in mesen-
Aorta.
tery, in several series, from terminal arches branches
(Plate 3.)
ramify on intestines.
Superior
Mesenteric.
/ Inferior, anas. Vasa intes. ten.
Ileo-colic < 0 . „ .. , ,
^ Superior, anas. Colica dextra.
/ Desc. Br. \ Arches branching to ascend-
Cohca Dextra \ . _ > .
1 Asc. Br. ) ing colon.
/ Right \ Arches, branching to trans-
Colica Media < _ * > .
\ Left ) verse colon.
Supra-renal, to supra-renal capsule.
. / Brs. to substance of kidney.
Renal \
{ Small Brs. to capsule, ureter, etc.
Spermatic (or Ovarian) to testes or ovaries, uterus, etc.
Inferior
(Asc. \ Arches branching to descend-
Colica Sinistra < ^ V
[ Desc. J ing colon.
Mesenteric.
Sigmoid, across Psoas to that flexure of colon.
(Plate A }
( KY tn ricrlit 1
^i late 4v
Sup. Hemorrhoidal, < ' ^ > side of rectum.
to muscles, etc., of back.
Spinal, to canal s „ ' \ Arches.
Abdominal, between abdominal muscles.
Middle Sacral, to coccyx, anas. Lateral Sacral.
/ RIGHT COM. ILIAC, R. Int. and Ext. Iliac (14, 15).
Bifu.rc3.t6S s
Bifurcation occurs at 4th Lumbar Vertebra, opposite Umbilicus.
BRANCHES OF THE AORTA
Plate 3.
Potter.del
157
HUMAN ANATOMY
THE ARTERIAL SYSTEM.— Continued
Superior Vesical
Obturator.
\ Art. of Vas Defer ens, to that organ.
\ Middle Vesical, to base of bladder.
14 a.
Internal Iliac or
Uterine, <
Hypogastric. ,
I
ANTERIOR
Vaginal, analog
TRUNK.
(Plate 4.)
Internal
Pudic, or
Pudendal.
Sciatic or
Inf. Gluteal.
Iliac, to iliac bone and Iliacus muscle.
Vesical, backward to the bladder.
Pubic, on the back of the pubic bone.
Internal, along inner margin obturator foramen.
External / outer margm obturator foramen.
\ Br. to hip-joint by cotyloid notch.
Inferior Vesical, to base of bladder, prostate gland, etc.
Middle Hemorrhoidal, to anus, anas, other hem. arteries,
f Br. to the bladder. ]
Br. to the ureter.
Cervical, to neck of uterus.
Azygos, of the vagina.
In the female.
Inferior Hemorrhoidal, 2 or 3 to the anus.
Superficial Perinaal, to the scrotum, etc.
Transverse Perinceal, to muscle of same name.
Artery of the Bulb, large but very short.
Artery of the Corpus Cavernosum, to that body.
Dorsal Artery of the Penis, or clitoris.
Muscular Brs. within the pelvis.
Hemorrhoidal Brs. to the rectum.
Vesical Brs. to base and neck of bladder.
Coccygeal, to back of coccyx.
Inf. Gluteal 3 or 4, to Gluteus maximus.
Comes Nervi Ischiadici, along sciatic nerve.
Muscular Brs. to back of hip.
Anastomotic, to the crucial anastomosis.
Articular Brs. to capsule of the hip- joint.
ARTERIES or THE PELVIS AND THIGH. Plate 4
FIG. 2
BRANCHES Ot OPHTHALMIC ARTtRY.
Potter .del
159
i6o
HUMAN ANATOMY
THE ARTERIAL SYSTEM.— Continued
14 b.
Internal Iliac or
Hypogastric.
POSTERIOR
TRUNK.
(Plate 4.)
Ilio-lumbar,
Iliac, to Iliacus internus and Ilium.
/ to Psoas and Quad, lumborum.
Lumbar,
\ Spinal Br. to cord and membranes.
Superior Lateral Sacral, to dorsum of sacrum.
Inferior Lateral Sacral, to front of sacrum, and coccyx, anas
with Sacra media, etc.
Gluteal,
Muscular Brs. within the pelvis.
Nutrient, of the Ilium.
Superficial, to Gluteus maximus, etc.
Superior, to ant. sup. spine of Ilium.
Inferior, to glutei and hip-joint.
Deep
Muscular Brs. several, to Psoas and glands.
15. [ Cremasteric, to cremaster muscle.
External Iliac. • Epigastric, -I Pubic, to inner side of femoral ring.
(Plate 4.) ( Muscular, to abdominal muscles and skin.
„. ,, rf. \ between Transversalis and Int. oblique.
Circumflex Iliac, < _ . . T , , _ . .
( Br. anas, with Lumbar and Epigastric.
Becomes FEMORAL (16) at Poupart's Ligament.
Superficial Epigastric, in superf. fascia, to umbilicus.
Superf. Circumflex Iliac, outward to iliac crest.
Superf. Ext. Pudic (pudendal) , inward to skin of penis, scrotum
etc.
Deep Ext. Pudic (pudendal), inward to skin of perineum, etc.
Asc. Brs. outer side of hip.
Ext. Circumflex, •{ Transverse, to back of hip.
Descending, as far as knee.
16.
Femoral.
(Plate 4.)
Profunda
Femoris,
I Ascending, to Adductors, etc.
Int. Circumflex, -j Descending, to Adductors, etc.
[ Articular, to head of femur,
f Superior, pierces Adductor magnus.
Perforating,^, Middle, < Nutrient of Femur.
{ Inferior, pierces Adductor magnus.
Muscular 2 to 7, along artery, to Sartorius, Vastus internus, etc.
j Superficial Br. to integument.
Anastomotica Magna,} Deep Br. to inner side of knee and joint,
or Genu Suprema. anas, with Sup. Articulars and Recur-
[ rent br. of Anterior Tibial.
Becomes POPLITEAL (17), at opening in Adductor magnus.
ARTERIES OF THE LEG. |
Plate 5
Potter.dei
II
161
HUMAN ANATOMY
THE ARTERIAL SYSTEM.— Continued
17-
Popliteal.
(Plate 4.)
Muscular
/ Superior Brs. to Vastus ext. and flexor muscles.
\ Inferior or Sural 2, to Gastrocnemius and Plantaris.
Cutaneous Brs. to integument of calf.
Superior Internal Articular, to Vastus int. and joint.
Superior External Articular, to Vastus ext. and joint.
Azygos Articular, to synovial membrane of joint.
Inferior Internal Articular, to head of tibia and joint.
Inferior External Articular, to front of knee-joint.
. , / ANTERIOR TIBIAL (i 8) \at lower border of Popliteus
Bifurcates into | pOSTERIOR TlBIAL (lp) | musde
Post. Recurrent Tibial, to the Popliteus muscle.
Superior Fibular, to the Soleus and Peroneus longus.
Ant. Recurrent Tibial, to the knee-joint anastomosis.
18. Muscular Brs. numerous to muscles of leg.
Anterior I Internal Malleolar, beneath tendon of Tibialis anticus.
Tibial. j External Malleolar, to outer ankle.
(Plate 5.) Tar sal, to tarsal joints and Ext. brev. digit.
7 Digital
branches.
Dorsalis Pedis
Metatarsal, < 3 Interossea,
Dorsalis Hallucis
Communicating,
Ends in the PLANTAR ARCH.
Brs. to great toe.
Br. to inner side of 2d toe.
anas. Ext. Plantar (Arch).
2 Digital Brs.
Peroneal,
Anterior Peroneal, pierces interosseous membrane.
Posterior Peroneal, to the os calcis.
Nutrient* Artery of the fibula.
Muscular, several brs. in its course.
/ joins similar branch of the poste-
Commumcating {
\ nor Tibial.
Ext. Calcanean, the terminal branches.
19. Muscular, to Soleus, etc., on back of leg.
Posterior I Nutrient of Tibia, the largest nutrient artery of bone.
Tibial. Communicating Br. to a similar br. of the Peroneal.
(Plate 5.) Internal Calcanean Brs. to the heel, and sole of foot.
Internal Plantar, along inner side of foot and great toe.
( Brs. to muscles, fascia and skin.
Posterior Perforating 3 Branches.
4 Digital, { Ant. Perforating Branches.
k I
Ends as the PLANTAR ARCH, anas, with Commun. Br. of Dorsalis Pedis.
External Plantar,
THE VEINS 163
THE VEINS
Veins are vessels which return the blood from the capillaries of the body
to the heart. Their walls, like those of the arteries, are composed of 3
coats — an internal serous (tunica intima), a middle muscular (tunica
media), and an external one (tunica externa or adventitia) of connective
tissue. Their middle coat is weaker than that of the arteries, so that they
do not stand open when divided, as the arteries do. They all carry carbon-
ized (venous) blood, except the pulmonary veins, which bring oxygenated
blood to the left side of the heart. The deep veins accompany the arteries,
generally in the same sheath, and are given the same names. The second-
ary arteries, as the radial, ulnar, brachial, etc., have each two veins, called
Vena Comites. The superficial veins are usually unaccompanied by
arteries, and lie, as a rule, between the layers of the superficial fascia,
terminating in the deep veins. Many veins are so irregular in their
origin that they cannot be accurately described; they all anastomose with
each other much more freely than do the arteries.
Venous Sinuses are venous channels, differing from veins in structure,
but answering the same purpose. Those of the cranium are formed by
the separation of the layers of the dura mater.
The Veins are divided into the Pulmonary, Systemic, and Portal Sys-
tems; the latter being an appendage of the systemic, its capillaries ramify-
ing in the liver.
Veins having no valves are the venae cavae, hepatic, portal, renal,
uterine, ovarian, cerebral, spinal, pulmonary, umbilical, and the very small
veins.
The Pulmonary Veins alone of the veins carry arterial blood, beginning
in the capillaries of the lungs, forming a single trunk for each lobule, which,
uniting into a single trunk for each lobe, form two main trunks from each
lung which open separately into the left auricle. Sometimes the three lobe-
trunks of the right lung remain separate to their termination in the auricle,
and not infrequently a common opening serves for the two left pulmonary
veins.
VEINS OF THE HEAD AND NECK
Exterior Veins of the Head and Face are as follows, —
Frontal Vein, — begins on the anterior part of the skull by a venous plexus
converging to a single trunk near the middle line of the forehead, which
joins the supra-orbital vein at the root of the nose to form the angular
vein.
Supra-orbital Vein, — begins on the forehead and joins the frontal (see
above) to form the angular vein.
1 64 HUMAN ANATOMY
Angular Vein, — formed as described above, runs downward and outward
on the side of the root of the nose, communicates with the ophthalmic
vein, and ends in the —
Facial Vein, — a direct continuation of the angular, begins at the side of the
root of the nose, descends obliquely across the masseter muscle and
over the body of the lower jaw to unite with the ant. division of the
temporo-maxillary to form the common facial vein, which enters the
internal jugular.
Temporal Vein, — begins on the vertex and side of the skull, by anterior and
posterior branches which unite and are joined by the middle temporal
above the zygoma to form the trunk, which descends through the parotid
gland and unites with the internal maxillary to form the temporo-
maxillary vein.
Internal Maxillary Vein, — is formed by branches corresponding to those of
the internal maxillary artery, forming the pterygoid plexus. The trunk
passes backward behind the neck of the lower jaw and unites with the
temporal to form the —
Temporo-maxillary Vein, — descends in the parotid gland and divides into
an anterior branch, which joins the facial, and a posterior branch which
is joined by the posterior auricular and becomes the external jugular.
Posterior Auricular Vein, — begins on the side of the head, descends behind
the external ear and joins the posterior division of the temporo-maxillary,
forming the external jugular.
Occipital Veins, — begin in a plexus at the back of the head and terminate
in the internal jugular.
Veins of the Diploe and Interior of the Cranium, —
- Veins of the Diploe, — a number of tortuous canals lying between the two
tables of the skull, and divided into frontal (empties into supra-orbital),
anterior temporal (empties into either the spheno-parietal sinus or ante-
rior deep temporal), posterior temporal and occipital branches which
empty into either the occipital vein or the lateral sinus (sinus
transversus) .^
Cerebral Veins, — have no muscular coat and no valves. They are divided
into superficial and deep sets. The deep cerebral are formed by the
union of the vena cor ports striati (vena terminalis) and the choroid vein
on either side, and receive the basilar vein, forming the great cerebral
vein (veins of Galen).
Ccrcbcllar Veins, — on the surface of the cerebellum, are disposed in 3 sets,
superior, inferior and lateral.
Superior Longitudinal Sinus (sinus longitudinalis vel sinus sagittalis
DURAL SINUSES 165
superior), — occupies the attached margin of the falx cerebri, begins at
the foramen caecum, and ends in the torcular Herophili (confluens
sinuum), or confluence of the sinuses.
Inferior. Longitudinal Sinus (sinus sagittalis inferior), — in the free margin
of the falx cerebri posteriorly, terminates in the —
Straight Sinus (sinus rectus or tentorial sinus), — at the junction of the falx
cerebri with the tentorium, terminates in the lateral sinus (sinus trans-
versus) of the opposite side.
Lateral Sinuses (sinus transversi), — in the attached margin of the ten-
torium cerebelli, terminate in the internal jugular vein.
,~" Occipital Sinuses (sinus occipital es), — in the attached margin of the falx
cerebri, terminate in the torcular Herophili.
Cavernous Sinuses (sinus cavernosi), — one on each side of the sella turcica,
receive the ophthalmic vein and open behind into the petrosal sinuses.
Circular Sinus (sinus circularis), — is formed by two transverse vessels, the
anterior and posterior intercavernous sinuses, connecting the two
cavernous sinuses, and forming a venous circle around the pituitary
body.
Superior Petrosal Sinus, — connects together the cavernous and lateral
sinuses of each side.
Inferior Petrosal Sinus, — begins at the termination of the cavernous sinus,
and joins the lateral sinus to form the internal jugular vein.
Transverse or Basilar Sinus (plexus basilaris], — connects the two inferior
petrosal sinuses over the basilar process of the occipital bone.
Emissary Veins (emissaria), — pass through apertures in the cranial wall
from the sinuses inside to the veins outside; the principal ones being 8
in number.
1. Frontal through foramen caecum.
2. Parietal (two) through parietal foramina.
.3. Occipital through foramen in occipital protuberance (occasional).
4. Post-condylar (condyloid) through foramen behind occipital condyle.
5. Emissary plexus through foramen ovale.
6. Vein of Vesalius through foramen of Vesalius.
7. Plexus through internal carotid canal.
8. Plexus through anterior condylar canal (hypoglossal canal).
Veins of the Neck, draining those above-mentioned, are the —
External Jugular (6), — terminating in the subclavian vein (4).
Posterior External Jugular, — opens into the external jugular.
Anterior Jugular (7), — enters the subclavian vein near the external jugular.
Internal Jugular (5), — formed by the junction of the two last-named
i66
HUMAN ANATOMY
sinuses at the jugular foramen, and uniting with the subclavian vein to
form the innominate, at the root of the neck. In its course it receives
the facial, lingual, pharyngeal, superior and middle thyroid veins, and
the occipital.
Vertebral, — descends the foramina in the transverse processes of the cervical
vertebrae, and empties into the innominate vein. In its course it
receives the anterior and posterior vertebral and many other veins.
VEINS OF THE UPPER EXTREMITY
Veins of the Hand, Forearm, and Arm are in two sets, superficial and
deep. The superficial set lies in the superficial fascia, begin in the hand
by external and internal dorsal and superficial galmar veins, and are
continued as follows, the basilic continuing as the axillary, which receives
the cephalic just below the clavicle.
Radial (cephalic B.N.A.) ./i^.^ \ f
. . > Cephalic
Median Cephalic }
Profunda
Median Basilic
Dorsal.
Palmar.
Dorsal.
Median (median
cubital)
I Anat. Ulnar
! (basilic B.N.A.
| Post. Ulnar
{ (basilic B.N.A.
Common Ulnar
(basilic B.N.A.)
Basilic
AXIL-
LARY
VEIN.
The deep veins follow the arteries, generally as venae comites, beginning
in the hand as Digital, Interosseous and Palmar veins, they unite in the
Deep Radial and Deep Ulnar, which join to form the Vena Comites of
the brachial artery at the bend of the elbow. The Brachial Veins lie
one on each side of the brachial artery and join the Axillary Vein. These
deep veins have numerous anastomoses, not only with each other but also
with the superficial ones.
Axillary Vein (v. axillaris), — the continuation of the basilic, lies on
the inside of the artery and terminates beneath the clavicle at the
outer border of the ist rib, where it becomes the —
Subclavian Vein (v. subclavia), — the continuation of the axillary,
extends from the outer border of the ist rib to the inner end of the
clavicle, where it unites with the internal jugular to form the in-
nominate vein. At the angle of junction enters the thoracic duct on
the left side of the body and the right lymphatic duct on the right
side. In its course it receives the external and anterior jugular
veins and a branch from the cephalic.
The Innominate Vein (vena anonyma) is formed by the union of the
VEINS OF THE THORAX
i67
subclavian and the internal jugular. The two innominates unite just
below the ist costal cartilage to form the superior vena cava. The
Right Innominate (v. anonyma dextra) (3) is
about i inch long, and receives, besides its FIG. 69.
constituent branches, the right internal mam-
mary, right inferior thyroid, and right superior
intercostal veins. The Left Innominate (v.
anonyma sinistra) (2) is about 2^ inches long;
in its course it receives the vertebral, inferior
thyroid, internal mammary, and superior inter-
costal veins of the left side.
VKIXS OF THE THORAX
The Veins of the Thorax include the follow-
ing vessels: —
,* Internal Mammary, (mamariainterna), — two to
each artery, unite into a single trunk which
terminates in the innominate vein.
Inferior Thyroid (vv. thyreoideae inferiores), —
2 to 4, form a plexus in front of the trachea,
which gives off the left and right inferior
thyroid veins, these receiving cesophageal,
tracheal and inferior laryngeal veins and
opening into the innominate veins.
Superior Intercostal, — the right vein (v. inter-
costalis suprema dextra) opens into the vena
azygos major, the left vein (v. intercostalis
suprema sinistra) into the left innominate.
Azygos Veins, — are described below.
* Bronchial, — return the blood from the lung
substance; the right one opens into the vena
azygos major, the left into the left superior
intercostal or the left upper azygos vein.
Spinal, — are described below.
Vena Cavce^ — are described below; the Superior Vena Cava under the
Veins of the Thorax, the Inferior Vena Cava under the Veins of the
Lower Extremity.
The Azygos Veins supply the place of the venae cavae in the region
where these trunks are deficient, being connected with the heart.
Vena Azygos Major (v. azygos) (17), — begins by a branch from the right
lumbar veins usually, passes through the aortic opening in the
l68 HUMAN ANATOMY
diaphragm, and ends in the superior vena cava, having drained 10
right lower intercostals, the vena azygos minor, (v. hemiazygos),
the right bronchial, cesophageal, mediastinal, and pericardial veins.
Left Lower Azygos (vena azygos minor or v. hemiaz3'gos) (18), — begins
by a branch from the left lumbar or renal, passes through the left
crus of the diaphragm, crosses the vertebral column and ends in the
right azygos, having drained 4 or 5 lower intercostals.
Left Upper Azygas (v. hemiazygos accessoria), — drains 3 or 4 left
intercostals and empties into either of the other two. It is often
wanting, its place being filled by the left superioi intercostal vein (21).
The Spinal Veins may be arranged in 4 sets, as follows: —
Qor si- spinal, — form a plexus around the spines, processes, and laminae
of all the vertebrae. They empty into the vertebral, intercostal, lumbar,
and sacral veins in their respective regions.
Meningo-rachidian, — in two longitudinal plexuses, anterior and posterior,
running the whole length of the spinal canal. The posterior join the
dorsi-spinal veins, the anterior empty into the vertebral, intercostal,
lumbar, and sacral veins in their various regions.
Vena Basis Vertebrarum—the veins of the bodies of the vertebrae, are
contained in large, tortuous channels in the substance of the bones, and
join the transverse trunk connecting the anterior longitudinal veins.
Medulli-spinale, — the veins of the spinal cord, lie in plexus form between
the pia mater and arachnoid. They unite into 2 or 3 small trunks near
the base of the skull, which terminate in the inferior cerebellar veins
or in the inferior petrosal sinuses.
The Superior Vena Cava (i) is a short trunk about 2^ or 3 inches in
length, formed by the union of the two innominate veins, thereby re-
ceiving all the blood from the upper half of the body, and opening into the
right auricle of the heart. It is half covered by the pericardium, and
receives the vena azygos major and small pericardiac and mediastinal
veins.
VEINS OF THE LOWER EXTREMITY
The Veins of the Lower Extremity are in two sets, superficial and deep.
The superficial are the —
Internal or Long Saphenous (saphena magna), — on the inside of the
leg and thigh, enters the femoral at the saphenous opening i >£ inch
below Poupart's ligament (1. inguinale). In its course it receives: —
Cutaneous Branches. Superficial Circumflex Iliac.
Superficial Epigastric. Communicating Branches.
Ext. Pubic, (venae pudendae externae).
VEINS OF THE PELVIS AND ABDOMEN 1 69
External or Short Saphenous (v. saphena parva), — formed by branches
from the dorsum and outer side of the foot, it ascends behind the
outer malleolus, up the middle of the back of the leg, and empties into
the popliteal vein, between the heads of the gastrocnemius muscle.
The deep veins are the vence comites of the arteries, beginning in the foot
as the external (lateral) and internal (medial) Plantar, which unite to form
the Posterior Tibial (venas tibiales posteriores). The vena comites of
the dorsalis pedis artery continue upward as the Anterior Tibial veins
(venae tibiales anteriores), which join the posterior tibial, forming the —
Popliteal, — which becomes the Femoral, and it the External Iliac, in
the same manner as the respectively named arteries.
VEINS OF THE PELVIS AND ABDOMEN
The Veins of the Pelvis, except the middle sacral, open into the internal
iliac vein. The middle sacral opens into the left common iliac.
The Internal Hiac Vein (vena hypogastrica) (10) is formed by the
venae comites of the branches of the internal iliac artery, and terminates
with the external iliac, at the sacro-iliac articulation, to form the common
iliac vein (v. iliaca communis). It receives the following veins: —
From the exterior of the pelvis, the —
Gluteal, (v. glutaea superior).
Sciatic (v. glutaea inferior).
Internal Pudic (vv. pudendae internae).
Obturator.
From the organs in the pelvic cavity the —
Hemorrhoidal Plexus. \ . Uterine Plexus. \ .
,, . , J . „, > in the male. ,,.,„, > in the female.
Vesico- pro static Plexus. J Vaginal Plexus. J
The Dorsal Vein of the Penis enters the prostatic plexus.
The Veins of the Abdomen include the Portal System, the Lumbar,
Spermatic, Renal, Suprarenal, Phrenic, Hepatic, External Iliac, Common
Iliac and the Inferior Vena Cava.
The External Iliac Vein commences at the termination of the femoral
beneath Poupart's ligament, and terminates opposite the sacro-iliac syn-
chondrosis by uniting with the internal iliac to form the common iliac
vein. It receives the Deep Epigastric (v. epigastrica inferior) and Deep
Circumflex Iliac, also a small pudic vein.
The Common Iliac Veins (n) are each formed by the union of the two
iliac veins as above described, and unite between the 4th and 5th lumbar
vertebras to form the inferior vena cava, the right common iliac being the
shortest of the two, Each receives the Ilio-lumbar, sometimes the Lateral
1 70 HUMAN ANATOMY
Sacral, and the left one in addition the Middle Sacral Vein, which some-
times ends in the vena cava.
The Inferior Vena Cava (8) extends from the junction of the two
common iliac veins, passing along the front of the spine, through the tendin-
ous centre of the diaphragm, to its termination in the right auricle of the
heart. It receives the following veins:
/ Lumbar (12), — 4 on each side, receive dorsal and abdominal tributaries,
also veins from the spinal plexuses, and terminate in the inferior vena
cava. They are connected together by the ascending lumbar, which
passes in front of the transverse processes of the lumbar vertebrae.
;,, Right Spermatic (13). — The spermatic veins arise from the testis and
epididymis, forming the spermatic or pampiniform plexus, which forms
the chief mass of the spermatic cord, and unite into 3 or 4 veins which
enter the abdomen through the internal ring, form 2 veins, then a
single one which opens on the right side into the inferior vena cava, on
the left side into the left renal vein. In the female they are called
Ovarian and terminate in the same way as in the male.
^ Renal (15), — are large veins, placed in front of the renal arteries, and
terminating in the inferior vena cava. The left is longer than the
f right and passes in front of the aorta.
•T Supra-renal, — on the right side ends in the vena cava, on the left side in
f^ the left renal or phrenic vein.
Phrenic 2, — the superior ends in the internal mammary, the inferior ends
oh "the right side in the vena cava, on the left side in the left renal vein.
Hj&atic Veins (16), — begin in the capillary terminations of the portal
vein and hepatic artery in the substance of the liver, uniting into 3
large veins from the right and left lobes and the lobulus Spigelii, which
open into the inferior vena cava. They have no valves.
The Portal System is formed by the Superior and Inferior Mesenteric,
Splenic, and Gastric Veins, which collect the blood from the digestive vis-
cera, and by their union behind the head of the pancreas form the Portal
Vein, which enters the transverse fissure of the liver, where it divides into 2
branches. These again subdivide, ramifying throughout the organ,
therein receiving blood also from the branches of the hepatic artery.
Its minute ramifications end in capillaries, from which the blood of the
portal system, together with that brought by the hepatic artery, is carried
by the hepatic veins to the inferior vena cava. The portal vein generally
receives the Cystic Vein, which sometimes terminates in the right branch
of the portaT
THE LYMPHATIC SYSTEM 17 1
VEINS OF THE HEART ITSELF
The Cardiac Veins return the blood from the tissue of the heart into the
right auricle. They are the —
. Great Cardiac Vein,
Right or Small Coronary Vein (v. coronaria ventriculi).
Posterior Cardiac Vein. S Anterior Cardiac Veins.
Coronary Sinus is a dilatation of the great cardiac vein, receiving the
Left Cardiac Veins. -^ Ven(B Thebesii.
Coronary Sinus is a dilatation of the great can
* posterior cardiac and an oblique vein from the left auricle.
THE LYMPHATIC SYSTEM
Lymphatics are very delicate, transparent vessels; the larger having 3
coats like the arteries and veins, the smaller having 2 coats, the external
and internal, but no middle muscular-elastic coat. Lymphatics are found
in nearly every texture and organ of the body which contains blood-
vessels, but are absent in the non-vascular structures, as cartilage, nails,
cuticle and hair. They are nourished by blood-vessels distributed to their
outer and middle coats, in which also many non-medullated nerve-fibres
have been traced. They possess valves of semilunar form, placed at
much shorter intervals than are the valves in the veins. They convey
lymph to the blood, and possess the property of absorbing certain materials
from the tissues and conveying them into the circulation; hence they are
also called absorbents. They discharge their contents into the blood at
two points, the junctions of the subclavian and internal jugular veins, on
the left side by the thoracic duct, on the right side by the right lymphatic
duct.
Lacteals are the lymphatic vessels of the small intestine, conveying chyle
to the blood during the process of digestion.
Lymphatic Glands (lymphoglandulas) are small, solid, glandular bodies,
placed in the course of the lymphatic and lacteal vessels, and found
chiefly along the great blood-vessels, at the root of the lungs, in the lumbar
and cceliac regions of the abdomen, in the mesentery, the mediastina, the
head, neck, axilla, groin, and popliteal space. They are named after the
respective regions in which they are situated, as axillary glands, the
inguinal, cceliac, bronchial, mesenteric, etc. They consist of a fibrous
capsule, from which trabecula are prolonged inward, dividing the gland
into alveoli or open spaces containing lymphoid tissue, the proper gland-
substance, which is so placed as to leave a channel (sinus), the lymph-
172 HUMAN ANATOMY
path, all around it. The glands are nourished by blood-vessels supported
on the trabeculae, and some fine nerve filaments are traced into them.
Before entering a gland the lymphatic (or lacteal) divides into several
small branches, the afferent vessels, of which the endothelial layer only enters
the gland, to form in its lymph-sinuses a plexus of vessels which unite into
a single efferent vessel. The external coat of the afferent vessels becomes
continuous with the capsule of the gland, and is received upon the efferent
vessel as it emerges.
Haemal Lymph Glands, — resemble ordinary lymph glands in all respects
save that some of their sinuses contain blood.
Haemal Glands, — all of their sinuses contain blood, otherwise they do
not differ from regular lymph glands. Both Haemal glands and Haemal
Lymph glands are more numerous in the retro-peritoneal tela along the
line of the aorta.
f/ . 3^ The Thoracic Duct (ductus thoracicus) is the main channel for the lymph
and chyle from the whole body except the right arm and lung, right side
of the head, heart, neck, and thorax, and the convex surface of the liver.
It begins in the abdomen by a triangular dilatation, the —
Receptaculum Chyli (cisternachyli), in front of the zd lumbar vertebra,
passes through the aortic opening in the diaphragm, and opposite the 7th
cervical vertebra it curves forward, outward and downward over the
subclavian artery, so as to form an arch, and terminates in the left sub-
clavian vein at its angle of junction with the left internal jugular vein. In
the thorax it lies in the posterior mediastinum in front of the vertebral
column, between the aorta on its left and the vena azygos major on its
right. It has numerous valves throughout its course, and a pair of valves
at its termination to prevent the passage of venous blood into its cavity.
The Right Lymphatic Duct (ductus lymphaticus dexter) is a short trunk,
about 2^2 inch in length and i% line in diameter. It terminates in the
right subclavian vein at its angle of junction with the right internal
jugular, its orifice being guarded by two semilunar valves against the
passage of venous blood into its cavity. It receives lymph from those
parts which are not connected with the thoracic duct, namely — the right
upper extremity, the right lung, the right side of the head, neck, heart
and thorax, and part of the convex surface of the liver.
LYMPHATICS OF THE HEAD AND NECK
Lymphatic Glands of the Head and Neck, are as follows: — •
Occipital (lymphoglandulae occipitales), i or 2, — at the back of the head,
close to the artery.
LYMPHATICS OF THE UPPER EXTREMITY 173
Posterior Auricular or Mastoid (lymphoglandulae auriculares posteriores),
2, — near the mastoid process.
Anterior Auricular (lymphoglandulae auriculares anteriores), — external to
the parotid gland.
Parotid (lymphoglandulae parotideae), — some in and others around the
parotid gland.
Buccal, i or more, — on the surface of the buccinator muscle.
Submandibular (lymphoglandulae submaxillares), — beneath the ramus of
the jaw.
Lingual (lymphoglandulae linguales), 2 or 3, — on the hyo-glossus and
genio-hyo-glossus muscles.
Retro-pharyngeal (lymphoglandulae retropharyngeae) 2, — one on each side
of the middle line.
Superficial Cervical (lymphoglandulae cervicales superficiales), — consisting
of the submaxillary, 8 to 10, the suprahyoid, i or 2, and the cervical
(many) in the course of the external jugular vein.
Deep Cervical (lymphoglandulae cervicales profundae superiores et infe-
riores), — forming a chain along the sheath of the carotid artery and in-
ternal jugular vein, in two sets, an upper, 10 to 20, and a lower, 10
to 15.
Lymphatic Vessels of the Head and Neck are — the/ Temporal and
; Occipital, in the scalp, respectively accompanying the temporal jand oc-
cipital arteries; the 'Meningeal an^ Cerebral, in the cranium; the Super-
ficial and the Deep, in the face; also those of the orbit, the temporal and
zygomatic fossae, the nose, tongue, pharynx, larynx and thyroid body.
In the neck these vessels are continuations of those on the cranium and
face.
LYMPHATICS OF THE UPPER EXTREMITY
Lymphatic Glands of the Upper Extremity (lymphoglandulae cubitales
superficiales et profundae) are in two sets, the Superficial, which are few
and small, and ih^Deep, in the forearm, the "arm and the axilla. The
Axillary Glands, 10 to 12, are of large size, situated around the axillary
vessels, in the tissue of the axilla, and in chains along the lower border of
the pectoralis major muscle and the lower margin of the posterior wall of
the axilla, they are grouped as follows: —
1. Brachial or lateral.
2. Subscapular or posterior.
3. Pectoral or anterior.
4. Central.
5. Subpectoral.
174 HUMAN ANATOMY
6. Infraclavicular.
7. Interpectoral.
8. Deltopectoral. (Robinson.)
Lymphatic Vessels of the Upper Extremity are the Superficial, beginning
on the sides of the fingers and accompanying the veins; the^Deep, occurring
in 4 sets corresponding with the radial, ulnar, and anterior and posterior
interosseous arteries.
LYMPHATICS OF THE LOWER EXTREMITY
Lymphatic Glands of the Lower Extremity are the — -Superficial Inguinal,
8 to 10, in two sets, an upper oblique set (lymphoglandulae inguinales)
along Poupart's ligament (1. inguinale), and an inferior vertical set (lympho-
glandulae subinguinales), 2 to 5, around the saphenous opening in the fascia
lata; Deep Glands are the anterior tibial popliteal (lymphoglandulae
popliteae), deep inguinal (lymphoglandulae subinguinales profundae),
gluteal and ischiatic.
Lymphatic Vessels of the Lower Extremity are in two sets, superficial
and deep. The Superficial lie in the superficial fascia in two groups, an
internal and an external, along the internal and external saphenous veins
respectively. The Deep are few in number and accompany the deep blood-
vessels.
LYMPHATICS OF THE PELVIS AND ABDOMEN
Lymphatic Glands are the external iliac, internal iliac, and sacral, in the
pelvis; and the lumbar and cceliac glands in the abdomen. The Lumbar
Glands are numerous, situated in front of the lumbar vertebrae, and sur-
round the common iliac vessels, the aorta and the vena cava. The Cceliac
Glands 20, surround the cceliac axis and lie in front of the aorta, receiving
the lymphatic vessels from a large part of the liver, the spleen, pancreas
and stomach.
Lymphatic Vessels of the Pelvis and Abdomen are in 3 sets, the super-
ficial, the deep, and those of the viscera. The Superficial follow the course
of the superficial blood-vessels, and include the lymphatics of the gluteal
region, the penis, scrotum and perinaeum. The Deep follow the course of
the principal blood-vessels. Those of the Viscera are the lymphatics of
the various organs contained in these cavities — the bladder, rectum,
uterus, kidney, liver, stomach, spleen and pancreas, and include those of
the testicles.
LYMPHATICS OF THE INTESTINES
Lymphatic Glands of the Intestines are those of the large intestine,
which are few in number, especially along the transverse colon; and those
LYMPHATICS OF THE THORAX 175
of the small intestine, 100 to 150, which lie between the layers of the
mesentery and are called the Mesenteric Glands (lymphoglandulae mesen-
tericae).
Lymphatic Vessels of the Intestines are those of the large intestine,
some of which enter the mesenteric glands, others the lumbar glands; and
those of the small intestine, called the Lacteals, from the milk-white fluid
(chyle) which they usually contain. The lacteals are in two sets, super-
ficial and deep, the latter occupying the submucous tissue and coursing
transversely around the intestine.
LYMPHATICS OF THE THORAX
Lymphatic Glands of the Thorax are those of the thoracic walls (lym-
phoglandulae sternales et intercostales) and those of the viscera. The
former are the intercostal, the internal mammary, and the anterior and
posterior mediastinal (lymphoglandulae mediastinales anteriores et
posteriores) glands; the latter are the bronchial and the superior medias-
tinal or cardiac glands. The —
Bronchial Glands (lymphoglandulae bronchiales), 10 to 12, — are situated
around the bifurcation of the trachea and the roots of the lungs.
Superior Mediastinal or Cardiac Glands, — are numerous and large, lie in
front of the transverse aorta and the left innominate vein, and receive
the lymph from the pericardium, the heart, and the thymus gland.
Lymphatic Vessels of the Thorax are the superficial, the deep and those
of the viscera in the thoracic cavity. The Superficial converge to the
axillary glands; the Deep are the intercostal, the internal mammary and the
diaphragmatic; those of the Viscera are the lymphatic vessels of the lungs,
heart, thymus gland and oesophagus.
THE NERVOUS SYSTEM
/ i. Brain.
i. Central part < _. . . _ ,
[ 2. Spinal Cord.
J i. Cranial Nerves.
.. Penpheral part
" \ 2. Sympathetic System ( '" £anglia' .
( 2. Communicating Branches.
Nervous Tissue is formed of two different structures, viz. Gray or cineri-
tious substance, in which nervous impressions and impulses originate; and
White or fibrous substance, by which the impressions and impulses are
conducted. Chemically, nervous tissue consists of proteids, neurokeratin,
i76
HUMAN ANATOMY
nucleiii, protagon, lecithin, cerebrosides, cholesterin, nitrogenous ex-
tractives and salts, with some gelatin and fat, and water; the latter varying
in different parts of the system, from 60 per cent, in the sciatic nerve, to
70 per cent, in the white matter of the cerebrum, and 83 per cent, in the
gray matter of the same region.
Gray Nervous Substance, the essential constituent of all the ganglionic
centres, is composed of nerve-cells or ganglionic corpuscles, containing nuclei
FIG. 70.
SHOWING SOME OF THE VARIETIES OF THE CELL-BODIES OF THE NEURONES OF
THE HUMAN NERVOUS SYSTEM, INCLUDING THE DENDRITES AND SMALLL PORTIONS
OF THE AXONES. AxoNE SHEATHS NOT INCLUDED. (Morris' Anatomy.)
A, From spinal ganglion. B. From ventral horn of spinal cord. C. Pyramidal
cell from cerebral cortex. D. Purkinje cell from cerebellar cortex. E. Golgi cell of
type II from spinal cord. F. Fusiform cell from cerebral cortex. G. Sympathetic.
a, axone; d, dendrites; c, collateral branches; ad, apical dendrites; bd, basal den-
drites; c, central process ; p, peripheral process.
and nucleoli. The cells are imbedded in a ground substance, neuroglia,
which consists of fibres and cells, and is a connective tissue in function
though not in development. A neurone is a nerve-cell together with all
of its processes. Nerve-cells vary in size and shape, and possess one or
more processes, according to the number of which they are grouped into
unipolar, bipolar and multipolar cells. Of these processes one is called the
THE NERVOUS SYSTEM 177
axone or axis-cylinder process, because it becomes the axis-cylinder of a
nerve- fibre; the others are termed dendrltes or protoplasmic processes.
White Nerve Substance or Nerve-fibre, contains two kinds of fibres,
the medullated or white and the non-medullated or gray. Medullated
Fibres contain a central core or axis-cylinder, the essential part of the
nerve-fibre, and regarded as a direct prolongation of a nerve-cell. This is
surrounded by the medullary sheath, or white substance of Schwann, com-
posed of fatty matter in a fluid state, which insulates and protects the
axis-cylinder. These are enclosed in the primitive sheath or neurilemma,
sometimes called the tubular membrane or sheath of Schwann, which is
absent in the fibres found in the brain and spinal cord. A bundle or
funiculus, of such fibres, held together by endoneurium, is surrounded by
perineurium, both formed of delicate connective tissue; and several funic-
uli are collected into larger bundles, fasciculi, which are bound together
by a common membrane, the epineurium, and then are called a Nerve,
The whole arrangement is precisely analogous to that of a submarine tele-
graph cable. The nerve is nourished by a minute system of capillary
blood-vessels, and has certain medullated fibres in the epineurium, termed
the nervi nervorum, or nerves of the nerves.
The Non-medullated Fibres, also called gray or gelatinous nerve-fibres, or
fibres of Remak, consist of a central core- or axis-cylinder enclosed in a
nucleated sheath. They constitute most of the sympathetic nerves and
include some of the cerebro-spinal.
Terminations of Nerves. Their origin or central termination occurs
from the nerve centre by one or two roots, in the latter case sometimes
widely apart from each other. The efferent nerve-fibres originate in
the cells of the gray substance, the afferent fibres branch among the cells
without uniting with them. The peripheral termination of sensory nerves
seems to be in minute primitive fibrilla or networks thereof; that of motor
nerves in special terminal organs, variously named, as the end-bulbs
of Krause, the tactile corpuscles of Wagner, the Pacinian corpuscles,
the neuro-tendinous and neuro-muscular spindles, and the motorial end-
plates of the striped or voluntary muscular fibre.
Ganglia are separate small aggregations of nerve-cells, connected with
each other, with the cerebro-spinal axis, and with nerves in various
situations. They consist of a collection of nerve-cells and nerve-fibres,
invested by a membranous envelope, which is continuous with the peri-
neurium of the nerves, and sends processes into the interior of the ganglion
to support the blood-vessels supplying its substance. They are found on
the posterior roots of all the spinal nerves, on the posterior (sensory) root
12
178 HUMAN ANATOMY
of the 5th cranial nerve; on the facial, auditory, glosso-pharyngeal and
pneumogastric nerves; also in a connected series along each side of the
vertebral column anteriorly, forming the trunk of the sympathetic, and
on the branches of that nerve.
THE BRAIN
Development of the Brain. At an early period of embryonic life the
cerebro-spinal axis consists of a thin-walled tube, the neural tube, which,
while still open at its caudal end, becomes enlarged at its cephalic end,
where constrictions appear, dividing this end into 3 primary vesicles,
the anterior, middle and posterior. From these vesicles are developed the
ventricles of the brain, the rest of the neural tube forming the central
cavity of the spinal cord. Thickenings of the wall of the neural tube
form the substance of the brain and spinal cord. The — •
Anterior Primary Vesicle, Prosencephalon, — divides into an anterior
(telencephalon) and a posterior (diencephalon] secondary vesicles.
From the telencephalon are developed the cerebral hemispheres;
corpora striata; corpus callosum; fornix; lateral ventricles;
olfactory lobe; front part of the third ventricle; front part of the
tuber cinereum; infundibulum; and the posterior lobe of the pituitary
body (hypophysis). From the diencephalon are developed, the optic
thalami (thalamus); corpora geniculata (metathalamus) ; pineal
body, the posterior part of the tuber cinereum; posterior part
of the third ventricle; corpora mammillaria; optic nerve and
optic tracts.
Middle Primary Vesicle, Mesencephalon, — its cavity becomes the
aqueduct of Sylvius, and with the parts developed around it con-
stitutes the mesencephalon or mid-brain. From the mesencephalon
are developed, corpora quadrigemina; pedunculi (crura) cerebri;
and aquaeductus cerebri (aquaeduct of Sylvius).
The constricted communication between the middle primary vesicle
and the posterior primary vesicle is known as the isthmus rhomben-
cephali, from it are developed the superior cerebellar peduncles
(brachia conjunctiva) and the valve of Vieussens (anterior medullary
velum).
Posterior Primary Vesicle, Rhombencephalon, — by constriction forms
an anterior secondary vesicle, metencephalon; and a posterior second-
ary vesicle, myelenccphalon.
From the metencephalon are developed the cerebellum; pons varolii
(pons) ; and front part of the fourth ventricle.
THE BRAIN 179
From the myelencephalon are developed the medulla oblongata and
the posterior portion of the fourth ventricle.
Structure of the Cerebrum. The cerebrum is composed of gray and
white matter, the former disposed in two great groups, — that of the cere-
bral cortex and that in the basal ganglia.
The Gray Matter of the Cortex is composed of 6 alternating white and
gray layers. The cortex is made up of nerve-cells and nerve-fibres. The
Nerve-cells are arranged in 5 layers, named, from the surface inward, as
follows: the fmolecular layer, the outer layer /'.of polymorphous cells, the
layer of small pyramidal cells, the layer of large pyramidal cells, the inner
layer of polymorphous cells. In certain parts of the cortex this arrange-
ment is variously departed from, as many as 9 layers being described in
the cuneus. The Nerve-fibres are either medullated fibres or naked axis-
cylinders embedded in a matrix of neuroglia.
The Basal Ganglia are a series of gang! ionic masses in the base of each
cerebral hemisphere, subjacent to the island of Reil, they and it constitut-
ing the oldest part of the hemisphere, the first to appear in the order of
development. They are semi-detached local thickenings of the gray
cortex, and are named as follows: —
Corpus Striatum, — composed of two nuclei, the caudate and the len-
ticular (lentiform) (described on page 191). Closely associated with
it are certain fasciculi of white matter, the — / £3cr/
Internal Capsule (page 192).
External Capsule (page 192).
Anterior Commissure (page 192).
Tania Semicircularis (stria terminalis) (page 190).
Claustfum, — a thin band of gray matter, described under the corpus
striatum on page 191.
Nucleus Amygdala, — a thickening of the cortex of the apex of the
temporal lobe, producing a bulge, the amygdaloid tubercle, in the roof
of the extremity of the descending cornu of the lateral ventricle.
The Optic Thalamus, though in close proximity to the corpus striatum,
is not placed among the basal ganglia of the hemispheres, being considered
part of the diencephalon or inter-brain.
The White Matter consists of medullated fibres in bundles, arranged in
the following 3 systems: —
PROJECTION FIBRES (peduncular), — connecting the hemispheres with
the medulla oblongata and the cord. They originate in the cells of
the cerebral cortex from whence they proceed, forming the corona
radiata as they converge to enter the internal capsule when they are
l8o HUMAN ANATOMY
collected into the several bundles which are continued as the crusta
(basis) of the crura (pedunculi) cerebri.
TRANSVERSE OR COMMISSURAL FIBRES, — connect the two hemispheres.
They are the transverse fibres of the corpus callosum, and the anterior
and posterior commissures of the 3d ventricle.
ASSOCIATION FIBRES, — connect different structures in the same hemi-
sphere; the short connecting adjacent convolutions; and the long,
connecting distant structures, as follows, the—
Uncinate Fasciculus, — from the frontal to the temporal lobe,
across the bottom of the fissure of Sylvius, (fissura cerebri
lateralis).
Cingulum, — antero-posteriorly in the convolution of the corpus
callosum, from the anterior perforated substance to the hook
of the uncinate gyrus (anterior end of the sup. occipito-temporal
gyrus).
Superior Longitudinal Fasciculus, — connects the frontal lobe with
the occipital and temporal lobes.
Inferior Longitudinal Fasciculus, — connects the temporal with the
occipital'lobe. It runs the entire length of both lobes and con-
nects their convolutions.
Perpendicular Fasciculus, — connects the inferior parietal lobule with
the inferior occipito-temporal convolution (gyrus fusiformis).
Fornix, — connects the hippocampal convolution (superior occipito-
temporal) with the corpora albicantia (corpora mammillaria)
and the optic thalamus..
THE MENINGES
Membranes of the Brain are the dura mater, the arachnoid membrane,
and the pia mater.
— 3 7 The Dura Mater is a dense fibrous membrane lining the interior of the
skull. It consists of two layers which are coalesced throughout the
greater part of their extent. The inner layer which is produced into the
intervals between parts of the brain forming partitions, and the outer
layer which is strongly attached at the base of the cranial cavity and
along the cranial sutures into which it sends processes. The outer
layer forms the internal periosteum of the cranial bones. It is con-
tinuous with the dura mater of the spinal cord, with the pericranium,
and the periosteum of the orbit; being prolonged to the outer surface of
the skull through the various foramina at its base. It sends 4 processes
into the cavity of the skull for the support of the different parts of the
brain, also several tubular processes and prolongations through orifices and
THE MENINGES l8l
foramina in the skull for the protection of nerve trunks and vessels. The
Cerebral dura mater derives its nerve supply from the 4th and 5th cranial
nerves, and from the sympathetic (Whitaker). It presents the following
points for examination —
Tht Mcningeal Arteries, — are on, or close to, the outer surface, whereas
the veins are deeply placed between the two layers and form
sinuses (see page 164).
Falx Cerebri, — an arched process into the longitudinal fissure of the brain
vertically; contains in its upper and lower margins the superior and
inferior longitudinal sinuses.
Tentorium Cerebelli, — a lamina of dura mater supporting the posterior
lobes of the brain, and covering the upper surface of the cerebellum.
It incloses the lateral and superior petrosal sinuses.
Falx Cerebelli, — projects between the lateral lobes of the cerebellum,
from the tentorium to the foramen magnum.
Diaphragma Sella, — a horizontal process forming a small circular fold
which almost covers the pituitary body and constitutes a roof for the
sella turcica.
Pacchionian Bodies (granulationes arachnoideales), — clusters of white
granulations situated on both the outer and inner surface of the dura
mater near the larger sinuses, and in the interior of the larger sinuses
(see page 182).
The Arachnoid Membrane is a delicate single-layer envelope which
covers the brain, lying between the dura mater and the pia mater, although
throughout a large part of its extent it is not distinct from the pia mater.
It is separated from the dura mater by the superficial cerebral veins. It
dips into the great longitudinal fissure of the brain and into the interval
between the cerebrum and cerebellum but it does not enter the fissures
between the convolutions of the brain. Processes of it are prolonged
around the cranial nerves as far as their points of exit from the skull. It
is supplied probably by the 5th, 7th and nth cranial nerves (Whitaker).
Subdural Space (cavum subdurale), — is the space between the arach-
noid and the dura mater. It contains a small amount of fluid of the
nature of lymph.
Subarachnoid Space (cavum subarachnoidalis), — is the interval between
the arachnoid and pia mater, forming the two large spaces, mentioned
below, at the base of the brain, but small on the surface of the hemi-
spheres. It is occupied by a spongy connective tissue, in the meshes
of which the cerebro-spinal fluid is contained. It communicates with
the genera] ventricular cavity of the brain by 3 openings, one of
1 82 HUMAN ANATOMY
which, the foramen of Magendie (metapore), is in the middle line at
the lower end of the roof of the 4th ventricle.
Anterior Subarachnoidean Space (cisterna interpeduncularis), — is the
interval between the arachnoid and the pia mater at the base of the
brain, where the former membrane extends across between the two
temporal lobes.
Posterior Subarachnoidean Space (cisterna cerebellomedullaris), — is a
similar interval between the hemispheres of the cerebellum and the
medulla oblongata. These two spaces communicate with each other
across the inferior cerebellar peduncles (corpores restiformes).
Cerebro-spinal Fluid, — occupies the subarachnoid space of the brain and
spinal cord, and also the ventricular cavities of the brain. Its
average quantity is about 2 oz., being most abundant in old persons.
It forms a water-bed for the protection of the nervous centres from
the effects of concussions.
Granulationes Arachnoideales or Pacchionian bodies, — are numerous,
small, granulations, which are not glandular in structure but
enlarged normal villi of the arachnoid; found on the outer and
inner surfaces of the dura mater, in the superior longitudinal sinus,
and on the pia mater. They are not usually found until after the
7th year of age, and are occasionally wanting.
The Pia Mater is a vascular membrane, supplied by branches of the in-
ternal carotid and vertebral arteries. It covers the surface of the brain,
dipping down into all the sulci, and forms the velum interpositum (tela
chorioidea ventriculi tertii) and choroid plexus (plexus chorioideus
ventriculi lateralis) of the lateral and 4th ventricles. It consists of a
minute plexus of blood-vessels, held together by a very fine areolar tissue;
and contains numerous lymphatic vessels and nerves, the latter being
derived from both the cerebro-spinal and sympathetic systems. Its
nerve supply is derived from 3d, 5th, 6th, 7th and 8th cranial nerves and
from the sympathetic (Whitaker).
Weight of the Brain. Its average weight in the male adult is from 1360
(Smith) to 1400 (Spitzka) grammes; in the female 1250 grammes (Spitzka),
of which the cerebrum is about seven-eighths.
Divisions of the Brain. The Brain may be divided into the Cerebrum,
the Cerebellum, the Pons Varolii (pons) and the Medulla Oblongata; but
for the descriptive purposes it is best considered under the following 5
divisions, viz. the —
Cerebral Hemispheres or Telencephalon, — comprising the various lobes,
the lateral and 5th ventricles, and the basal ganglia.
THE BRAIN 183
Inter-brain or Diencephalon, — the region of the 3d ventricle, including
also the optic thalami and the pineal gland.
Mid-brain or Mesen-cephalon, — comprising the crura cerebri, the corpora
quadrigemina, the corpora geniculata, and the aqueduct of Sylvius
(aquaeductus cerebri).
Hind-brain or Melencephalon, — comprising the pons Varolii, the cere-
bellum, and the upper half of the 4th ventricle.
Medulla Oblongata or Myelencephalon, — including the lower half of the
4th ventricle.
The Cerebrum or Telencephalon. The cerebrum presents an ex-
ternal surface of gray matter called the cortex, the large upper part
of which is called the Pallium or Mantle; the smaller lower or basilar
part is called the Rhinencephalon. The surface of the brain presents
numerous clefts; some of these clefts cause a corresponding projec-
tion into the cavities of the interior of the brain and are called
Fissures (fissurae) in order to distinguish them from the others called
Sulci, which are those clefts which separate lobes (or lobules) from each
other. Clefts that separate the lobes from each other are called
inter-lobular sulci, while those that divide lobes into convolutions or
gyri are known as intra-lobular sulci. The cerebrum is divided into
two hemispheres by the Great Longitudinal fissure (fissura longi-
tudinalis cerebri).
THE CEREBRAL HEMISPHERES
Lobes in each Hemisphere, are as follows: —
Frontal Lobe, — bounded internally by the longitudinal fissure, below by the
fissure of Sylvius (fissura cerebri lateralis), and posteriorly by the
fissure of Rolando (sulcus cerebri centralis).
Parietal Lobe, — extending down to the fissure of Sylvius (fissura cerebri
lateralis), and antero-posteriorly from the fissure of Rolando (sulcus
cerebri centralis) to the external parieto-occipital fissure.
Occipital Lobe, — behind the parieto-occipital fissure.
Temporal Lobe, — lying in the middle fossa of the skull, and bounded in
front by the fissure of Sylvius (fissura cerebri lateralis).
Central Lobe, or Island of Reil (Insula), — lies in the fissure of Sylvius
(fissura cerebri lateralis) covered by the frontal and temporal lobes.
Limbic Lobe, — arches around the corpus callosum and the hippocampal
fissure; is well developed in animals having a keen sense of smell.
Olfactory Lobe, — situated on the under surface of the frontal lobe, and
divided into the olfactory bulb, the olfactory tract, the trigonum, and
184 HUMAN ANATOMY
the posterior olfactory lobule (ant. perforated space or substantia per-
forata anterior).
Fissures of the Cerebrum are as follows: —
Longitudinal Fissure (fissura longitudinalis cerebri), — extends from the
front of the cerebrum to the back, separating it into two hemispheres,
which are connected in the middle portion by the central commissure,
the corpus callosum (10), forming the floor of the fissure in this part of
its length.
Syhian Fissure, or Fissure of Sylvius (fissura cerebri lateralis), — on each
side at the base and lateral side of the brain. Starting at the anterior
perforated substance it passes outward to the external surface of the
hemisphere, where it divides into a short anterior limb (ramus anterior
horizontalis), a short ascending limb (ramus anterior ascendens), and
a horizontal limb (ramus posterior). It lodges the middle cerebrav
artery.
Fissure of Rolando (sulcus cerebri centralis) (i), — on the superior surface
of each hemisphere, extending from the longitudinal fissure about it?
centre, downward and forward toward the fissure of Sylvius, separating
the frontal and parietal lobes. This fissure is said to be found only in
man and the higher primates.
Parieto-occipital Fissure, — extends from the longitudinal fissure outward
for about an inch between the parietal and occipital lobes.
Calloso-marginal Fissure (sulcus cinguli), — above the gyrus fornicatus
(gyrus cinguli) on the inner surface of each hemisphere.
Internal Parieto-occipital Fissure, — extends downward and forward to join
the calcarine fissure, on 'a level with the hinder end of the corpus cal-
losum.
Calcarine Fissttre (fissura calcarina), — begins close to the posterior extrem-
ity of the hemisphere, runs horizontally forward, joined by the parieto-
occipital fissure, and terminates a little below the posterior end of the
corpus callosum (u).
Collateral Fissure, — below and external to the preceding, runs forward
from the posterior extremity of the brain nearly as far as the tip of the
temporal lobe.
Dentate or Hippccampal Fissure, — commences behind the posterior end
of the corpus callosum (n) and runs forward to the recurved part
(uncinate gyrus) of the hippocampal gyrus (posterior horizontal part
of the sup. occipi to- temporal convolution).
Transverse Fissure, — a horse-shoe shaped gap or cleft at the base of the
brain, extending from the foramen of Munro on each side to the termina-
THE BRAIN
FIG. 71.
tion of the descending cornu of the lateral ventricle. One-half the
fissure is in each hemisphere, and it admits an invagination of the pia
mater, which forms the choroid plexus in the lateral ventricle and the
velum interpositum (tela chorioidea ventriculi tertii) in the 3d ventricle.
It gives exit to the venae Galeni.
Parallel Fissure, formerly called the first temporo-sphenoidalfisstire, — on the
lateral surface of the hemisphere below the fissure of Sylvius (fissura
cerebri lateralis).
Cerebral Convolutions. The superior and inner surfaces of each hemi-
sphere are formed of convolutions (gyri) with intervening fissures and de-
pressions (sulci) of various depths,
the gyri and sulci being both
formed of gray matter thus ar-
ranged to enable it to present a
great extent of surface. The con-
volutions are not uniform in all
brains as to arrangement, nor are
they symmetrical in the two
hemispheres. The principal con-
volutions are the following-
named : —
On the Frontal Lobe are 8, ex-
t e r n a 1 1 y — the ascending
(gyrus centralis anterior)
(2), superior (4), middle (5)
and inferior (6) frontal; in-
feriorly the internal, anterior
and posterior orbital. The
inferior frontal on the left
side is named the convolution
of Broca and is the language
centre.
On the Parietal Lobe., are 4,
externally — the ascending
(gyrus centralis posterior)
(3), superior and inferior
parietal, and the quadrate or
precuneus, internally. The inferior parietal is subdivided into the
supramarginal, the angular, and postparietal gyri, the latter (2) lying
around the posterior end of the superior temporal sulcus (parallel
fissure) (see above).
1 86 HUMAN ANATOMY
The Occipital Lobe has 4, externally — the superior (7), middle (8) and
inferior (9) occipital; and internally the cuneate lobule or cuneus.
Temporal Lobe has 5 gyri, — externally, the superior, mfddle, and
inferior temporal gyri; below on the tentorial surface, the superior
occipito-temporal (gyrus lingualis or subcalcarine), and the inferior
occipi to- temporal (gyrus fusiformis). Part of the inferior temporal
gyrus also shows on this surface. On the upper surface, two or three
indefinite gyri can be seen. The superior occipito-temporal lobe is by
some considered to be two lobes, in which case, its anterior, upwardly
hooked portion is called the uncinate gyrus, the posterior horizontal
portion being called the hippocampal gyrus.
The Central Lobe or Island of Reil (insula), is subdivided by the sulcus
centralis into the precentral lobe (pars frontalis) and the postcentral
lobe (pars occipitalis). The insula is pyramidal in shape and consists
of 5 or 6 convolutions called gyri operti.
Under Surface of the Base of the Brain, from before backward, ex-
cluding the vessels and the cranial nerves, shows the following points for
examination. In the middle line are the —
Longitudinal Fissure, — its anterior portion separating the frontal lobes,
and its posterior portion between the occipital lobes.
Corpus Callosum, — the great transverse commissure, seen in the longi-
tudinal fissure, and showing its peduncles, one on each side, to meet
the corresponding outer root of the olfactory tract.
Lamina Cinerea, — a thin, triangular, gray layer, continuous with the
anterior perforated space (locus perforatus anterior). In the mid-
line it is divided into a right and a left portion by a very thin almost
transparent portion — the lamina terminalis, which forms the anterior
and inferior boundary of the 3d ventricle.
Optic Commissure, — formed by the junction of the optic tracts.
Tuber Cinereum (17) — a gray lamina behind the optic commissure, form-
ing part of the floor of the third ventricle. From it projects the —
Infundibulum, — a hollow process, its canal connecting the pituitary
cavity with the 3d ventricle in the foetus.
Eminentia Saccularis, — between the corpora albacantia or mammillaria
and the tuber cinereum, it is a trefoil-shaped eminence homologous
with the saccus vasculosus of the lower vertebrates.
The Pituitary Body or Gland (Hypophysis Cerebri), — is a small oval body
depending by the infundibulum from the tuber cinereum in the floor
of the third ventricle. It occupies the pituitary fossa (fossa hypo-
physeos) in the sella turcica of the sphenoid bone. It consists of two
THE BRAIN
FIG. 72.
27
THE BASE OF THE BRAIN
i. Olfactory Bulb. 2. Second, or Optic Nerves. 3. Anterior Perforated Space.
4. Optic Tract. 5- Crus Cerebri. 6. 3d Nerve. 7. 4th Nerve. 8. sth Nerve. 9.
6th Nerve. 10. Pyramid, n. Olivary Body. 12. Vertebral Artery. 13. Anterior
Spinal Artery. 14. Anterior Cerebral Artery. 15. Lamina Cinerea. 16. Middle
Cerebral Artery. 17. Tuber Cinereum. 18. Corpora Albicantia. 19. Posterior
Perforated Space. 20. Posterior Cerebral Artery. 21. Superior Cerebral Artery.
22. Pons Varolii. 23. Inferior Cerebellar Artery. 24. 7th and Sth Nerves. 25.
9th, loth and nth Nerves. 26. I2th Nerve. 27. Cerebellum.
1 88 HUMAN ANATOMY
lobes. Anterior (buccal or glandular) lobe is the larger, it secretes
a colloid substance much like that of the thyroid gland (glandula
thyreoidea). Its structure is much like that of the para-thyreoid
bodies. It consists of compartments which are lined with cuboidal
cells of two varieties. The principal cells are the more numerous;
they are small cells with very granular cytoplasm. The large cells
are chromophile cells. The anterior lobe is derived from the primitive
buccal cavity (stomatodaeum). Posterior or cerebral lobe is the
smaller and is connected by the infundibulum to the tuber cinereum,
but is not known to be functional. It is composed chiefly of neu-
rogliar connective tissue and blood-vessels, throughout which are
interspersed numerous branched cells. It has no organized structure.
It is derived from the hypophyseal diverticulum of the diencephalon.
The hypophysis gets its blood supply from the hypophyseal branches
of the internal carotid artery, it is classed as one of the ductless glands.
Corpora Albicantia (corpora mammillaria) (18), — two round, white
eminences, united together; they are the anterior crura of the fornix
folded on themselves.
Posterior Perforated Space (Pans Tarini or Substantia Perforata Posterior}
(19), — perforated for vessels to the optic thalami; forms part of the
floor of the 3d ventricle.
Pons Varolii (pons) (22), — a broad band of white fibres, passing from
one cerebellar hemisphere to the other described on page 203.
Medulla Oblongata (13), — pyramidal in form, emerges from the posterior
border of the pons Varolii. It is described on page 208,
On each side of the middle line are seen the —
Frontal Lobe, — its under surface (see ante, page 185); lying thereon is
the—
Olfactory Lobe, — consisting of the olfactory bulb (i), the olfactory
tract, the trigonum olf actorium, and the posterior olfactory lobule or
anterior perforated space (3).
Anterior Perforated Space (substantia perforata anterior), (3) or pos-
terior olfactory lobule, — at the commencement of the fissure of Sylvius
(fissura cerebri lateralis); is perforated for small arteries going
to the corpus striatum.
Fissure of Sylvius (fissura cerebri lateralis), — is described on page 184.
Optic Tract (4), — runs obliquely across the crus cerebri as a flat band,
and enters into the optic commissure.
Crus Cerebri or Cerebral Peduncle (5), — a thick bundle of white matter
in front of the anterior border of the pons, passing forward and out-
ward to enter the undfir surface of the hemisphere. The two crura
THE BRAIN 189
connect the cerebrum with the cerebellum, medulla oblongata and
spinal cord. With the optic tracts they form the boundaries of the
inter -peduncular space.
Temporal Lobe, — its under surface (see page 186).
Cerebellum (27), — covering the occipital lobe of the cerebrum. It is
described separately on page 206.
Ventricles of the Brain are 5 in number, of which the two lateral and
the 5th belong to the cerebral hemispheres, the 3d is the cavity of the
interbrain, and the 4th belongs to the cerebellum and the medulla oblon-
gata. They are situated as follows: —
Two Lateral Ventricles, (ventriculi laterales), — within the substance of
the hemisphere, one in each; they are connected with the 3d
ventricle and indirectly with each other by the foramina of Munro
(foramina interventricularia) and the 3d ventricle.
Third Ventricle (ventriculus tertius), — a narrow crevice between the
optic thalami, lying below the lateral ventricles and communicating
with them by the foramina of Munro (foramina interventricularia).
It is connected with the 4th ventricle by the iter a tertio ad quartum
ventriculum or aqueduct of Sylvius (aquaeductus cerebri).
Fourth Ventricle (ventriculus quartus), — between the cerebellum and
the medulla oblongata.
Fifth Ventricle (cavum septi pellucidi), — between the two laminae
of the septum lucidum (septum pellucidum), between the two lateral
ventricles. It is not a true ventricle.
The Lateral Ventricles are two irregular cavities in the cerebral hemi-
spheres, separated from each other by a partition, the septum lucidum,
(or pellucidum), and each having a central cavity and 3 prolongations or
cornua, the anterior in the frontal lobe, the middle in the temporal lobe
and the posterior in the occipital lobe. They communicate with each
other and with the 3d ventricle by the foramina of Munro (foramina
interventricularia). The central cavity (pars centralis) is situated in the
parietal lobe and is bounded as follows: —
Roof, — the under surface of the corpus callosum.
Floor, — from before backward, the caudate nucleus of the corpus
striatum, taenia semicircularis (stria terminalis), optic thalamus,
choroid plexus, the thin sharp free edge of the lateral half of the
fornix and its posterior pillar.
Internally, — the septum lucidum (septum pellucidum), separating it
from the opposite ventricle.
Externally, in front and behind, — brain-substance.
190 HUMAN ANATOMY
Structures named above are briefly described as follows: —
Corpus Callosum, — the great transverse commissure, arching backward
to become continuous with the fornix, reflected below, forming the
peduncles at the entrance of the fissure (lateral cerebral) of Sylvius;
and marked above by a depression, the Raphe, and longitudinal ele-
vations, the stria longitudinales, mediates and laterales, or nerves of
Lancisi.
Septum Lucidum (septum pellucidum), — consists of 2 layers of white
and gray matter, lined by epithelium; is placed vertically between the
lateral ventricles, from the raphe of the corpus callosum above to
the fornix below. The cavity in its centre is the 5th ventricle (or
cavum septi pellucidi).
Fornix, — is a commissure situated beneath the corpus callosum, but
continuous with it posteriorly, the septum lucidum (s. pellucidum)
separating them in front. It is composed of association fibres
which are axis-cylinder processes connecting different parts of the
same hemisphere. It is of triangular form with the apex in front.
Its anterior pillars curve downward to the base of the brain, are there
reflected, forming the corpora atticantia (corpora mammillaria),
and end in the optic thalami. Its posterior pillars (crura fornicis)
pass down the descending horns of the lateral ventricles, along the
concavities of the hippocampi majores, and are each continued as the
corpus fimbrialum or t&nia hippocampi, into the uncus or hook of
the hippocampal convolution. The Lyra (psalterium) is a series of
markings on its under surface.
Foramina of Munro (foramina inter ventricularia), — together form a
Y-shaped opening situated between the anterior pillars of the fornix
in front and above and the anterior extremities of the optic thalami
below and behind. Each is crescentic in outline and by it the lateral
ventricles communicate with the 3d ventricle and with each other.
Tania Semicircular is (Stria Terminalis), — consists of commissural
fibres passing between the corpus striatum and the optic thalamu?.
Choroid Plexus of Veins, — is the margin of a fold of pia mater which
enters at the transverse fissure, passes up the descending cornu,
through the foramen of Munro, and as the Velum Interpositum
(tela chorioidea ventriculi tertii) spreads out over the roof of the 3d
ventricle.
Corpus Striatum, — is described on page 191.
Optic Thalamus, — is described on page 193.
Cornua of the Lateral Ventricles. The Anterior Cornu (cornu anterius)
curves over the anterior end of the corpus striatum into the frontal lobe.
THE BRAIN 191
The Posterior Cornu (cornu posterius) curves downward and inward in
the occipital lobe, and contains a smooth eminence, the Hippocampus
Minor, which is caused by the calcarine fissure; below thisis a slight eleva-
tion called the calcar avis. As the calcar avis and the hippocampus
diverge from each other they leave a triangular interval called the tri-
gonum collaterals. The Middle Cornu (cornu inferius) descends into
the temporal lobe to the transverse fissure at the base of the brain,
curving backward, outward, downward, forward, and inward (initials
of the directions form the mnemonic word BODFI). On its floor are the
following: —
Hippocampus Major, — a white eminence, about 2 inches long, formed
by the infolding of the cerebral cortex to produce the dentate or hippo-
campal fissure.
Pes Hippocampi, — the scolloped end of the hippocampus.
Pes Accessorius (Eminentia Collateralis] , — between the hippocampi, at
the junction of the middle and posterior cornua, it is caused by the
collateral fissure.
Corpus Fimbriatum, — a continuation of the posterior pillar of the fornix
(crus fornicis).
Choroid Plexus of Veins, — a process of pia mater (see page 190).
Dentate Convolution (fascia dentata), — a band of gray matter, just
below the fimbria, its free border is notched by the branches of the
choroid artery.
Transverse Fissure (fissura chorioidea), — at the extremity of the cornu,
extending to the foramena of Munro (foramena interventricularia).
It is described on page 184.
The Fifth Ventricle (cavum septi pellucidi) is a narrow chink situated
between the layers of the septum lucidum (septum pellucidum), and there-
fore lies between the lateral ventricles. In the ftetus it communicates
with the 3d ventricle by an opening between the anterior pillars of the
fornix (columnar fornicis). Originally it was part of the longitudinal
fissure and was shut off by the union of the hemispheres in the formation
of the corpus callosum above and the fornix below. It usually contains
fluid, of the nature of lymph.
The Corpus Striatum is a body of gray matter imbedded in the white
substance of each hemisphere, and is partly seen in the lateral ventricle
and its anterior cornu, this part being the —
Nucleus Caudatus (caudate nucleus), — the intra-ventricular portion; a
pear-shaped mass having its narrow end on the outer side of the optic
thalamus.
IQ2 HUMAN ANATOMY
Nucleus Lentiformis (lenticular nucleus), — the extra- ventricular por-
tion, only seen in sections of the hemisphere. It is divided by the
white external and internal laminae into three portions, the two medial
portions together constitute the globus pallidus, the remaining part
is much the larger and is called the putamen.
Internal Capsule, — a curved lamina of white matter separating the
caudate nucleus from the lenticular (lentiform) posteriorly. It is
formed by projection fibres from the crus cerebri, the corpus stria-
turn and the optic thalamus. [Projection fibres are axis-cylinder
processes connecting cells in the gray matter of the hemispheres
with other cells at lower levels in the cerebro-spinal axis.] Its
anterior limb (pars frontalis) is the portion in front of the curve
or genu, its posterior limb (pars occipitalis) lying behind the genu.
External Capsule, — a lamina of white matter bounding the putamen of
the lenticular (lentiform) nucleus externally, and made up of asso-
ciation fibres from the anterior commissure and the subthalamic
region.
Claustrum, — a thin layer of gray matter on the outer surface of the
external capsule, regarded as a detached portion of the gray matter
of the island of Reil (insula).
THE INTER-BRAIN
The Inter -brain or Thalamen-cephalon (Diencephalon) is the region
of the 3d ventricle, and is connected in front and above with the cerebral
hemispheres, behind with the mid-brain or mesencephalon. Its upper
surface is covered by iheforrrix; inferiorly it reaches the base of the brain,
it comprises the following structures, — optic thalami, corpora geniculata
(metathalamus), pineal body (corpus pineale), posterior part of the
tuber cinereum, posterior part of the third ventricle, corpora albicantia
(corpora mammillaria), optic nerve, and optic tract.
The Third Ventricle (ventriculus tertius) is a mere fissure, situated
in the mid-line, between the optic thalami. It communicates with the
lateral ventricles above by the foramina of Munro (foramina interven-
tricularia) and with the 4th ventricle behind by the iter a terio ad
quartum ventriculum (aquaeductus cerebri). It is crossed by 3 bands,
the anterior, middle, and posterior commissures, the middle one being of
gray matter, the others of white.
Anterior Commissure, — is composed of commissural fibres, it appears to
connect together the corpora striata; its fibres are traced into the
temporal lobes, and include fibres from the olfactory tract of the
THE BRAIN 193
opposite side. Commissural fibres are axis-cylinder processes which
connect identical parts of the two hemispheres.
Middle Commissure (massa intermedia), — is composed of gray matter
and connects the two optic thalami.
Posterior Commissure, — is composed of commissural fibres (see above); it
stretches across from one optic thalamus to the other, and contains
fibres connecting the two thalami, besides decussating fibres from
various parts of the mid-brain.
Boundaries of the Third Ventricle are as follows: —
Roof, — the velum interpositum (tela chorioidea ventriculi tertii), and
above it the fornix.
Floor, — the parts comprised in the interpeduncular space at the base of
the brain, viz. — the tuber cinereum, with its infundibulum and
pituitary body, corpora albicantia (corpora mammilaria), posterior
perforated space (substantia perforata posterior). Eminentia sac-
cularis, and chiasma optica.
Anteriorly, — the anterior pillars of the fornix (columnae fornicis), and
the lamina terminalis which joins the right and left half of the lamina
ceneria.
Posteriorly, — the pineal gland (corpus pineale), posterior commissure
and the iter a terio ad quartum ventriculum (cerebral aqueduct).
Laterally, — the optic thalami and the peduncles of the pineal body.
The Optic Thalami are two large, oblong masses, composed mainly of
gray matter and situated on either side of the 3d ventricle, between the
diverging portions of the corpora striata. Their outer and inferior
surfaces are blended with contiguous parts of the brain; their upper, inner
and posterior surfaces are free. They are intimately connected, by com-
municating fibres, with the tegmenta of the crura cerebri, the optic tract,
the cerebral cortex, the corpora striata and the corpora albicantia (corpora
mammillaria). Each optic thalamus terminates anteriorly as a rounded
point —
Anterior Tubercle, — containing the anterior nucleus.
As they pass backwards the optic thalami diverge outwards from
each other and each terminates as a rounded swelling, the
Posterior Tubercle or Pulvinar to which is attached laterally the external
geniculate body (corpus geniculatum laterale).
Corpora Geniculata (metathalamus) four oval eminences, a pair of
which is situated below and external to the pulvinar of the thalamus
on each side of the brain.
External Geniculate Body (corpus geniculatum laterale) the larger of the
IQ4 HUMAN ANATOMY
pair, is at a higher level and is slightly anterior as well as external
or lateral to the internal geniculate body (corpus geniculatum
mediale). The external geniculate body (corpus geniculatum
laterale) belongs to and is properly a part of the optic thalamus, it
receives the outer or lateral limb of the optic tract.
Internal Geniculate Body (corpus geniculatum mediale) receives the
outer part of the inner or medial limb of the optic tract. These
fibres do not however enter the eye, they originate in one of the
inferior corpora quadrigemina (colliculus inferior) on one side of the
brain, run forwards, cross by way of the optic chiasm, and then run
backwards to the internal (lateral) genicutate body and inferior
colliculus of the side opposite to that of their origin, this constitutes
what is known as the commissure of Gudden.
Pineal Body (corpus pineale), or epiphysis cerebri, is a small oval,
reddish vascular body (or gland), situated in front of the anterior
corpora quadrigemina (colliculi superiores) in the mid-line, just
over the opening of the aquaeductus cerebri (Sylvius) into the third
ventricle. It derives its blood supply from the velum interpositum
(tela chorioidea ventriculi tertii) to which it is firmly attached. It
has two peduncles which run forwards, one on each side of the third
ventricle, on the inner or medial surfaces of the optic thalami, to join
the anterior pillars of the fornix (columnae fornicis).
The pineal body, classed as one of the ductless glands, is not com-
posed of nervous elements but consists of numerous follicles which are
lined by epithelium. Some of the follicles are filled with a very viscid
liquid containing many epithelial cells constituting what are known as
corpora amylacea, some contain sabulous concretions of lime, magnesia,
and ammonia salts (brain sand) constituting what is known as the acervulus
cerebri. The pineal body is homologous to the so-called "pineal eye" of
some reptiles and some of the other lower vertebrates.
Trigonum Habenulae, a small triangular space with the apex pointing
forward, and its base corresponding to one of the anterior corpora
quadrigemina (colliculus superior). It is the interval between one
of the crura or peduncles of the pineal body and the optic thalamus of
the same side. In this triangle is a cluster of nerve cells forming the
ganglion habenulce.
The Mesencephalon or Mid-brain is the so-called isthmus cerebri.
It is the constricted portion which connects the pons (varolii) with the
diencephalon (inter-brain or thalamen-cephalon) and the cerebral hemi-
spheres. Comprised in it, on its ventral surface are the two crura (pedun-
THE BRAIN I 95
culi) cetebriy and on its dorsal surface are the four corpora quadrigemina
(colliculi). It is traversed by the eqtusductus cerebri (Sylvius). Above
and in front, it is continuous with the diencephalon or inter-brain, and
below with the pons Varolii.
The Crura Cerebri (pedunculi cerebri), two thick conical stalks
which constitute the stems of the cerebral hemispheres, are the upward
continuation of the medulla oblongata. Their parallel portions are
blended and held together by a mesial raphe which is indicated in front
or ventrally by a longitudinal groove. This portion is covered in front
or ventrally by the pons Varolii. The crura (peduncles) as they emerge
above the upper border of the pons Varolii, diverge laterally from
each other, enlarging as they ascend.
Each crus (pedunculus) then passes beneath the optic thalamus and
enters a cerebral hemisphere and continues to the internal capsule. As
seen from in front or ventrally, the interval between the divergent crura
(pedunculi) cerebri is called the inter-peduncular space.
In this space are the corpora albicantia (corpora mammillaria) .
The floor of the space is formed by the substantia perforata posterior also
called the posterior perforated space. The inner or medial sides of the
crura (pedunculi) cerebri are grooved by the superficial origin of third or
oculo-motor nerves. Winding forward around the outer or lateral
sides of the crura (pedunculi) cerebri are the optic tracts and below them,
the fourth or trochlear nerves. On the dorsal surface of the crura
(pedunculi) cerebri are the corpora quadrigemina (colliculi) supported
by the lamina quadrigemina covering in the aquaeductus cerebri
(Sylvius).
Upon cross section, each crus (peduncle) will be found to consist of
two portions which are separated from each other by a darker colored
portion called the substantia nigra, the portion that is in front of or
ventral to the substantia nigra is the Crusta or Pes (Basis Pedunculi)
Cerebri; the portion that is behind or dorsal to the substantia nigra is the
Tegmentum.
The Crusta (Basis Pedunculi) Cerebri constitutes the anterior or ventral
part of the crura (pedunculi) cerebri. It is composed entirely of longi-
tudinal fibres which descend from the cerebral hemisphere (corticifugal
fibres) most of which are continuous with the pyramidal tracts of the
medulla. Three principal tracts or bundles are recognized: ist, pyramidal
tracts in the middle and inner portions of the crusta, the inner part being
the geniculate fasciculus and the outer the pyramidal tracts proper; 2df
cortico-pontine; and 3d, caudate-cerebellar tracts.
196 HUMAN ANATOMY
The pyramidal (cerebro-spinal) tracts are direct motor strands com-
posed of descending cortico-spinal projection fibres which originate in the
following way. As the axis-cylinder processes descend from cells in the
precentral cerebral cortex, they form the corona radiata by converging as
they approach the internal capsule. They then proceed through the
genu and the anterior two-thirds of the posterior limb (pars ocdpitalis} of
the internal capsule to be continued as the pyramidal tracts in the crusta
(basis) of the crus (pedunculus) cerebri. Here they are differentiated
into an inner and an outer portion.
The inner portion is the part of the pyramidal tract that came down
through the genu of the internal capsule, it is continued as the gen-
iculate fasciculus, the fibres of which terminate in the nuclei of the
5th, yth, and i2th cranial nerves.
The outer portion of the pyramidal tract is the part that traversed the
anterior two-thirds of the pars ocdpitalis (posterior limb) of the in-
ternal capsule, it is continued as the, —
i. Pyramidal Tract Proper through the pons Varolii into the anterior
pyramid (ventral area) of the medulla where its fibres are differenti-
ated into three strands, the crossed, the direct, and the uncrossed.
Crossed Pyramidal Tract (fasciculus cerebro-spinalis lateralis).
Most of the fibres of the pyramidal tract proper decussate in the
medulla (inferior pyramidal motor decussation) and are then con-
tinued downwards as the crossed pyramidal tract (lateral cerebro-
spinal fasciculus) in the lateral column (funiculus lateralis) of the
spinal cord (medulla spinalis), on the side opposite to that of their
origin, to ultimately become connected with the anterior roots of
the spinal nerves.
Direct Pyramidal Tract (fasciculus cerebro-spinalis anterior) or
fasciculus of Tiirck, is composed of fibres of the pyramidal tract
proper which do not decussate in the medulla but continue downwards
in anterior column (funiculus anterior) of the spinal cord (medulla
spinalis), on the same side as that of their origin, where at various
levels its fibres cross through the gray matter of the cord to become
connected with anterior nerve roots of the opposite side.
Uncrossed Pyramidal Tract comprises those fibres of the pyramidal
tract proper which do not decussate either in the medulla or in the
cord but continue downwards in the lateral column (funiculus lateralis)
of the spinal cord (medulla spinalis), on the same side as that of their
origin, where they mingle with the fibres of the crossed pyramidal
tract (fasciculus cerebro-spinalis lateralis) and become connected
with anterior nerve roots on the same side as that of their origin.
THE BRAIN IQ7
2. The Cortico-pontine Tracts are the first link of the neurone chain
constituting the indirect motor tract, the complete series being
cerebral cortex; cortico-pontine tract; nucleus points; cerebellar
cortex; dentate nucleus; superior peduncle (brachium conjunctevum)
of cerebellum; red nucleus (nucleus ruber); rubro-spinal tract;
spinal gray matter; spinal nerve to muscle. There are two groups
of cortico-pontine fibres, —
Fr onto- p online tract, during its passage through the cerebral peduncle
lies medial to the geniculate fasciculus of the pyramidal tract. Origi-
nating in the mid-frontal cortex, its fibres pass through the back
part of the anterior limb (pars frontalis) of the internal capsule con-
tinuing by way of the crusta (basis) pedunculi cerebri to the nucleus
pontis.
Temporo-pontine tract which lies posterior and lateral to the principal
portion of the pyramidal tract during its course through the crus
(pedunculus) cerebri. Originating in the cortex of the two lowermost
temporal gyri, its fibres pass inwards under the lenticular (lentiform)
nucleus, traverse the postero-inferior part of the posterior limb
(pars occipitalis) of the internal capsule, continuing by way of
the crusta (basis) of the crus (pedunculus) cerebri to the nucleus
pontis.
3. Caudate-cerebellar Tract (stratum intermedium) occupies the interval
•""between the substantia nigra which is posterior, and the pyramidal
and cortico-pontine tracts which surround it in front and laterally.
It is made up of fibres running from the caudate nucleus to the
cerebellum.
Substantia Nigra, — is a dark band of pigmented gray matter, semi-
lunar in cross section. It divides the basilar (crusta) portion of the
cerebral peduncle (crus) from the tegmental portion.
Tegmentum, — of the cerebral peduncle (crus) consists of network of
transverse and longitudinal fibres among which are enmeshed many
scattered nerve cells and two well-defined clusters of nerve cells.
The gray matter (substantia grisea) of the tegmentum is continu-
ous with the formatio reticularis of the pons and medulla, the prin-
cipal nuclear clusters are, —
1. Stratum Griseum Cenlrale, — which is the gray matter surrounding
the aquasductus cerebri (Sylvius).
2. Red Nucleus (nucleus tegmenti ruber), — consists of multi-polar
cells, it is situated beneath the anterior corpus quadrigeminum
(colliculus superior).
It is the termination of the superior cerebellar peduncles (brachia
198 HUMAN ANATOMY
conjunctiva). Some of the fibres originating in it run up to the
ventro-lateral nucleus of the thalamus, others descend in the rubro-
spinal tract.
While Matter (substantia alba), — of the tegmentum consists both of
transverse and longitudinal fibres. Its transverse fibres mostly
enter into the formation of oculo-motor and trochlear nerves, q. v.
Its longitudinal fibres are mostly sensory and ascend towards the
brain cortex (corticipital). They are differentiated into the follow-
ing main bundles.
i. Medial Lemniscus (medial fillet). The tegmental and pontine
portion consists of ascending (corticipital) sensory nerve fibres after
they have emerged from the superior pyramidal sensor.y decussation
which is just above the nucleus gracilis and nucleus cuneatus in the
back part of the medulla oblongata. They convey sensory impulses
from muscles, bones, and joints. The medial lemniscus is formed by
the combination of fibres arising from the nuclei of the fasciculus
gracilis and fasciculus cuneatus. They originate in the following
way, — The sense-organs in muscles, bones, and joints are connected
by the peripheral processes (dendrites) to the ganglion cells (ist
neurones of the chain) in the ganglia on the posterior roots of the spinal
nerves, by way of which, the central processes (axones) of those cells
enter and then run upwards in the posterior column (funiculus
posterior) of the spinal cord (medulla spinalis) on the same side as
that of their origin. All those coming from spinal nerves below the
8th thoracic, are combined to form the Fasciculus Gracilis (column
of Goll) occupying the medial portion of the posterior column (funicu-
lus posterior) of the cord, in which position it continues as it runs
upwards to the medulla where it terminates in an expansion enclosing
the nucleus gracilis, this upper portion being known as the clava.
The Fasciculus Cuneatus (column of Burdach) originates in exactly
the same way from all of the spinal nerves above the Qth thoracic.
It runs upwards, laterally to the fasciculus gracilis, in the posterior
column (funiculus posterior) of the cord until it reaches the medulla
in which it terminates as an expansion enclosing the nucleus cuneatus.
The 2d neurones of the chain after leaving the nucleus gracilis or
nucleus cuneatus, may go by way of the inferior cerebellar peduncle
(corpus restifcrme) to the cerebellar cortex of the opposite side, or
they may decussate in the medulla (superior Pyramidal sensory
decussation) and then proceed as medial lemniscus or fillet by way of
the pons through the tegmentum of the crus (pediculus) cerebri of
the side opposite to that of their origin; then through the thalamus,
THE BRAIN 1 99
or through the posterior limb (pars occipitalis) of the internal capsule,
to the cerebral cortex.
2. Lateral Lemniscus (lateral fillet), is the upward continuation of
the cochlear division of the central auditory tract. Its fibres are
derived in the following way, — The cochlear nerve arises from the cen-
tral processes of the T-shaped cells (ist neurone of the chain) in the
spiral ganglion of the cochlea, it then passes backwards and
enters the medulla, beneath the lower border of the pons on
the outer side of the restiform body. Its fibres then divide into
ascending and descending branches. The fibres of the ascending
branch terminate in the cells of the ventral cochlear nucleus, which
lies in front of the restiform body in the interval between the cochlear
and vestibular divisions of the auditory nerve (n. acusticus). The
fibres of the descending branch terminate in the cells of the dorsal
cochlear nucleus, which lies beneath the trigonum acusticum, behind
the restiform body and between it and the flocculus of the cerebellum.
The axones of the cells (2d neurone) in the dorsal and ventral
cochlear nuclei form two bundles, of which the dorsal bundle or striae
medullares cross the floor of the 4th ventricle to the medial plane in
which they penetrate the tegmentum and decussate, some of the
fibres entering the lateral lemniscus of the opposite side, others enter-
ing the trapezoid body (corpus trapezoideum).
The axones in the ventral bundle (trapezia!) enter the trapezoid body
where some of them terminate in the large cells (3d neurone) constituting
the nucleus trapezoideus. Most of these trapezial axones decussate before
terminating in the superior olive. The axones leaving the superior olive
(4th neurone) are joined by the axones of the dorsal bundle (strife medul-
lares) so constituting the lateral lemniscus (lateral fillet) which bends
upwards and is again interrupted by the nucleus lemnisci lateralis (5th
neurone) whence it proceeds by way of the tegmentum to the nucleus of
the posterior quadrigeminal body (colliculus inferior) (6th neurone) and
to the medial geniculate body (;th neurone) from which arise axones that
pass through the sub-lenticular portion of the internal capsule, then by way
of the temporal portion of the corona radiata to the auditory area in the
cortex of the superior and transverse temporal gyri. A few fibres reach the
posterior corpora quadrigemina (colliculi inferiores) without having
decussated.
3. Ventral Longitudinal Fasciculus (tecto-spinal or mesencephalo-
spinal tract, or sulco-marginal fasciculus), — is composed of axones
descending from the anterior corpora quadrigemina (colliculi supe-
riores). These fibres immediately commence to decussate ( optic
200 HUMAN ANATOMY
acoustic reflex path") and as they descend, continue to decussate
through the medial raphe on each side of which they lie. During the
course of this tract through the pons and medulla many of its fibres
terminate in the nuclei of all of the motor cranial nerves, the tract it-
self enters the anterior column (funiculus anterior medullas spinalis)
of the cord on the side opposite to that of its origin. Continuing down-
wards, between the direct pyramidal tract (ventral cerebro-spinal
fasciculus) and the anterior medial fissure, its fibres terminate in
cells of the anterior horn (columna anterior).
4. Medial Longitudinal Fasciculus (posterior longitudinal bundle), — is
composed mostly of short association fibres. It originates in a special
nucleus of its own that is situated in that part of the floor of the 3d
ventricle which is immediately behind, or above, the corpora albicantia
(corpora mammillaria); it passes downwards, close to the mid-line,
between the medial lemniscus (medial fillet) and the gray matter
(substantia griesea centralis) of the aquaeductus cerebri (Sylvius),
where it becomes intimately connected with the nuclei of the 3d,
4th, and 6th cranial nerves, and the cells of the anterior corpus quad-
rigeminum (colliculus superior) It continues downwards close to the
mid-line immediately in front of the gray matter forming the floor of
the 4th ventricle where it becomes connected with the nuclei of the
7th and vestibular portion of the 8th cranial nerves. It gives off
and receives many collaterals in the formatio (substantia) reticularis
as it traverses the pons and medulla in order to enter the anterior
column (funiculus anterior medullae spinalis) of the cord where its
fibres terminate in the cells of the anterior horn (columnae anterior).
This tract seems to be made up mostly of fibres which have decussated.
Throughout its entire course it always lies close to the mid-line
immediately in front of the central gray matter, of whatever structure
it traverses.
5. Spino-thalamic Tract, — is composed of direct ascending fibres which
transmit sensation of pain, heat and cold, pressure and touch, from the
skin on one side of the body to the opposite side of the brain. The
sensory end-organs of the skin are connected with the peripheral
processes (dendrites) of cells in the ganglia of the posterior roots of
the spinal nerves. The central processes (axones) of these cells are
connected with cells in the gray matter of the posterior horn (columna
posterior) of the cord (medulla spinalis) from which axones pass
forwards and cross by way of the anterior white commissure to the
opposite side of the cord (medulla spinalis) where they ascend, at
first loosely scattered, in the antero-lateral funiculus, they ultimately
THE BRAIN 2OI
become condensed into a distinct tract or fasciculus which ascends
in the lateral side of the medulla, continues upwards through the pons,
medial to the olivo-cerebellar and rubro-spinal tracts, then, along
with the medial lemniscus, it traverses the tegmentum and the
posterior limb (pars occipitalis) of the internal capsule to terminate
in the thalamus.
6. Superior Peduncles (brachia conjunctiva) of the Cerebellum, — consists
of fibres originating in the dentate nuclei of the cerebellum. They
are two white bands, a right and a left, which emerge, widely apart,
from the front of the cerebellum. As they run upwards and for-
wards they converge forming the lateral boundaries and a small por-
tion of the roof of the front or upper half of the 4th ventricle. They
join each other in the mid-line, decussate and then pass upwards
under cover of the posterior pair of corpora quadrigemina (colliculi
inferiores) each one terminating in the red nucleus (nucleus tegmenti
ruber) of the side opposite to that of its origin.
7. Rubro-spinal tract (pre-pyramidal or Monakow's tract), — is a
descending crossed motor strand which seems to be the downward
continuation of some of the fibres of the superior peduncles (brachia
conjunctiva) of the cerebellum which having come from the dentate
nucleus and crossed to the red nucleus of the opposite side, are by
means of the rubro-spinal tract connected to their original side of the
spinal cord. The fibres of the rubro-spinal tract originate in the red
nucleus (nucleus tegmenti ruber) just beneath the anterior corpus
quadrigeminum (colliculus superior) they cross the medial plane to
the opposite side, descend close to the lateral lemniscus behind the
trapezium in the pons, becoming superficial in the medulla, where
they lie in the furrow of the lateral area or pyramid between the olive
and the spinal tract of the trigeminal nerve, they enter the lateral
column (funiculus lateralis) of the spinal cord (medulla spinalis)
where they continue downwards immediately in front of the crossed
pyramidal tract (fasciculus cerebro-spinalis lateralis) which is in-
vaded by some of the fibres, the others terminating in the cells of the
anterior horn (columna anterior).
8. Descending (Mesencephalic) Root of the Trigeminal Nerve, — enters
into the composition of the Masticator Nerve (motor portion of the
fifth). Its fibres originate in the giant pyramidal cells in the lower
part of the somaesthetic (sensory-motor) area of the cerebral cortex.
These pyramidal fibres traverse the genu of the internal capsule,
continue through the tegmentum, medial to the superior peduncle
(brachium conjunctivum) of the cerebellum, then decussate before
202 HUMAN ANATOMY
terminating in accessory motor nucleus of the fifth nerve. This
nucleus is also known as the Mesencephalic Nucleus of the Masticator
Nerve, it is a column of gray matter lateral to the gray matter (stra-
tum griseum centrale) surrounding the cerebral aqueduct (Sylvius).
9. Olivary Fasciculus (thalamo-olivary or central tegmental tract), —
is composed of fibres that originate both in the lenticular (lentiform)
nucleus and the thalamus, traverse the central portion of the tegmen-
tum and continue in the pons, behind the medial lemniscus in the
formatio reticularis to the inferior olivary nucleus, being continued
from the olive to the opposite cerebellar hemisphere by way of the
cerebello-olivary fibres.
Corpora Quadrigemina (colliculi) are 4 rounded eminences placed in
pairs, 2 in front and 2 behind, on the dorsal surface of the mid-brain
(mesencephalon) immediately behind the 3d ventricle and beneath the
posterior border of the corpus callosum. All 4 collectively are often called
the Tectum or Tectum Mesencephali, e.g., in names such as uteclo-spinal.n
The upper or anterior pair were called the nates (colliculi superiores), the
lower pair the lestes (colliculi inferiores). They are connected by 4 bands,
the brachia, with the corpora geniculata, those of the anterior corpora
quadrigemina (colliculi superiores) being continued directly into the optic
tract. They are composed of white matter externally and gray matter
internally. The anterior pair contain the —
Stratum Zonale, — a thin stratum of white matter on the surface.
Stratum Cinereum (stratum griseum colliculi superioris), — next below,
a layer of gray matter.
Stratum Opticum, — the upper gray- white layer, having many fine nerve-
fibres intersecting the gray matter.
Stratum Lemnisci, — the deep gray-white layer, consisting of nerve-
fibres and nerve-cells of large size.
Aqueduct of Sylvius, or Her a tertio ad quartum ventriculum (aquaeductus
cerebri) is a narrow canal, about ^ inch long, connecting the 3d ventricle
with the 4th, and situated between the corpora quadrigemina (colliculi)
and the tegmentum. It is surrounded by a layer of gray matter (stratum
griseum centrale) which is continuous with the gray matter of the 3d and
4th ventricles, and contains groups of cells which are connected with the
roots of the 3d, 4th and 5th cranial nerves.
The Hypo-thalamic Region (right or left), — is the forward prolongation
of the tegmentum becoming blended with the under surface of the thala-
mus, it consists mainly of the upward and forward production of the red
nucleus (nucleus tegmenti ruber), medial lemniscus (fillet), and the sub-
THE BRAIN
203
stantia nigra which is here expanded laterally by an additional cluster of
nerve cells forming the Nucleus Hypothalamicus.
The Rhombencephalon morphologically comprises: i. isthmus rhom-
bencephali, 2. metencephalon, and 3. myelencephalon.
Isthmus Rhomb encephali (isthmus of the hind-brain) comprises:
a. Superior Peduncles (brachia conjunctiva) of the cerebellum (see
page 201).
b. Superior Medullary Velum (valve of Vieussens) is triangular in shape
with the apex pointing forwards. It forms the roof of the anterior
or upper half of the 4th ventricle by filling up the interval between
the two superior peduncles (brachia conjunctiva) of the cerebellum.
It consists of a lamina of white matter which is crossed on its upper
surface by several transverse bands of gray matter which collec-
tively are known as the lingula cerebelli.
The Metencephalon or the Hind-brain, — comprises the pons Varolii,
the Cerebellum, and the upper half of the 4th Ventricle. The latter is
described with its lower half, under the Medulla Oblongata, in the next
section.
FIG. 73.
13
17
The Pons Varolii (6), is the bond of union of the various parts of the
brain, connecting the cerebrum with the cerebellum (3) and the medulla
oblongata (9). It is about i^ inch wide and i inch long and thick, and is
situated between, the hemispheres of the cerebellum above the medulla
oblongata and below the crura (pedunculi) cerebri. It consists of — a
ventral or anterior portion (pars ventralis) (7), containing layers of trans-
•)
4
jj
4
2CH HUMAN ANATOMY
verse and longitudinal fibres, also a small quantity of gray matter, a
tegmental, dorsal, or posterior portion (pars dorsalis), which is a continua-
tion of the reticular formation of the medulla, most of its constituents
being continued into the tegmentum of the crura (pedunculi) cerebri.
The Gray Matter of the Pons consists of the following important
collections of nerve-cells: —
Superior Olivary Nucleus (nucleus olivarius superior), — an isolated mass
of gray matter situated on the dorsal surface immediately above the
inferior olivary nucleus (nucleus olivarius inferior) of the medulla.
Nuclei of the $th Nerve 2, — one for the motor (12) and one for the sensory
root (13), the latter external to the former.
Nucleus of the 6th Nerve, — beneath the floor of the 4th ventricle, close
to the root of the facial nerve; its fibres pass through the pons and
emerge at its lower margin (14).
Nucleus of the Facial (jth) Nerve, — situated deeply below the floor of the
4th ventricle; its roots follow a tortuous course in the pons, emerging
at its lower border (15), external to those of the abducent nerve.
Nuclei of the Auditory (Sth) Nerve 2, — are dorsal and ventral, both lying
chiefly in the medulla but prolonged into the pons; the roots emerging
at its lower border (17), in the groove between the olivary body (oliva)
and the restiform body (corpus restiforme).
Nuclei Pontis, — small masses of gray matter in the ventral or anterior
portion of the pons.
Substantia Gelalinosa (of Rolando), — which is continuous with that of
the spinal cord and medulla.
Locus Cceruleus, a slate-colored bluish spot on the upper part of the
floor of the 4th ventricle.
The White Matter of the Pons consists of 4 sets of medullated nerve
fibres, superficial transverse, superficial longitudinal, deep transverse and
deep longitudinal.
The Superficial Transverse Fibres, — are on the ventral surface of the
pons, they continue laterally into the middle peduncles (brachia
pontis) of the cerebellum.
The Superficial Longitudinal Fibres of the pons comprise, — •
1. Upward continuation of the anterior pyramids (ventral area) of
the medulla (see page 209).
2. Cortico-pontine Tracts (see page 197).
3. Stratum Intermedium or Caudate-cerebellar Tract (see page 197).
The Deep Transverse Fibres, — form the trapezium (corpus trapezoideum)
and then pass laterally into the middle peduncles (brachia pontis)
THE BRAIN 205
of the cerebellum (see lateral lemniscus, page 199, and acoustic nerve,
page 220).
The Deep Longitudinal Fibres, — of the pons constitute a portion of the
reticular formation in which the following distinct bundles can be
traced, —
1. Olivary Fasciculus, Thalamo-olivary or Central Tegmental Tract
(see page 202), lies in the reticular formation dorsal to the medial
lemniscus.
2. Descending or Mesencephalic Root of the Trigeminal Nerve (see
page 201).
3. Fasciculus Teres, is composed of fibres of the facial nerve which, by
looping upwards behind the nucleus of the abducens nerve and then
running forwards and upwards, forms the eminentia teres or medialis
(colliculus facialis) which lies in the floor of the anterior or upper
half of the 4th ventricle, immediately lateral to the mid-line.
4. Medial Lemniscus or Fillet (see page 198), which comprises the
fasciculus gracilis (column of Goll) and the fasciculus cuneatus
(column of Burdach).
5. Lateral Lemniscus or Fillet (see page 199), composed of the cochlear
fibres of the central auditory path.
6. Ventral Longitudinal or Sulco-marginal Fasciculus (Tecto-spinal
or Mesencephalo-spinal Tract) (see page 199).
7. Medial Longitudinal Fasciculus (Posterior Longitudinal Tract)
(see page 200).
8. Rubro-spinal Fasciculus (Pre-pyramidal or Monakow's Tract) (see
page 201).
9. Ascending Antero-lateral Tract of Cowers, comprises a direct
and an indirect path through which sensation of pain, temperature,
pressure, and touch reaches the brain.
a. Spino-thalamic Tract is the direct path (see page 200).
b. Ventral Spino-cerebellar Tract (Superficial Ventro-lateral
Spino-cerebellar Fasciculus) is the indirect path. The term
"Cowers' Tract" is limited by some to this tract only. It
originates in the following way, the sensory end organs are con-
nected with the peripheral processes (dendrites) of cells in the
ganglia of the posterior roots of spinal nerves, the central proc-
esses (axones) of these cells are connected with cells in the
base of the lateral horn (columna lateralis), known as"Stillings'
Nucleus," and with cells in the lateral horn (columna lateralis)
of the spinal cord (medulla spinalis). The axones of these cells,
both of the same and the opposite side, are agminated into a
206 HUMAN ANATOMY
bundle, the Ventral Spino-cerebellar Tract (Superficial Ventro-
lateral Spino-cerebellar Fasciculus) which travels upwards in the
lateral column (funiculus lateralis) of the spinal cord (medulla
spinalis). It maintains this position as it traverses the medulla
until it reaches the pons where it runs forwards and upwards as
high as the level of the trigeminal nerve, it then runs backwards
and downwards, enters the superior peduncle (brachium conjunc-
tivum) of the cerebellum, and terminates in the lingula of the
superior vermis cerebelli of its own side.
The Cerebellum consists of gray matter (substantia corticalis) on the
surface and white matter (corpus medullare) in the interior. Its surface
is not convoluted like that of the cerebrum, but is traversed by curved
fissures and furrows (sulci), the latter separating the laminae (folia or gyri)
of which it is composed. It lies in the inferior occipital fossae of the skull,
beneath the occipital lobes of the cerebrum, from which it is separated by
a process of dura mater, the tentorium cerebelli. It is divided into a cen-
tral portion or lobe, the Vermis Cerebelli or Vermiform Process (i), and two
lateral Hemispheres; all continuous with each other and- substantially the
same in structure. It presents the following primary fissures: —
Great Horizontal Fissure (10), — horizontally round the free margin,
from the pons in front to the median line behind, giving origin to the
secondary fissures.
Incisura Cerebelli Anterior, or Anterior Cerebellar Notch, — a broad,
shallow, vertical notch, separating the hemispheres in front.
Incisura Marsupialis (2), or Posterior Cerebellar Notch, — a deep notch,
separating the hemispheres from each other behind.
Vallecula, — a deep depression on the inferior surface, containing the
lower extremity of the vermis (vermis inferior).
Secondary Fissures of the Cerebellum are 8 in number, 4 superiorly and
4 inferiorly. They pass in a curved direction from side to side across the
cerebellum, beginning (except one) and ending in the great horizontal
fissure. They are named from before backward as follows:
On the upper surface of the cerebellum, the —
Pre-central. Post-central. Anterior Semilunar or Pre-clival.
Posterior Semilunar or Post-clival.
On the lower surface of the cerebellum, the —
Post-nodular. Retro-tons illar or Pre- pyramidal.
Anterior Inferior or Post-pyramidal. Posterior Inferior or Post-gracile.
The post-gracile is a branch of the post-pyramidal, and ends in the
great horizontal fissure.
THE BRAIN 207
Lobes of the Cerebellum. The 3 primary lobes, the Vermis or Worm
and the Hemispheres, are divided by the above-named secondary fissures
into 19 lobes, named as follows: —
On the upper surface of the Worm (vermis superior), from before
backward 5, the —
Lingula. Lobulus Centralis. Culmen Monticuli.
Diclive or Clivus Monticuli. Folium Cacuminis or Commissura Simplex.
On the upper surface of the Hemispheres, from before backward 5, the —
Vinculum Lingualce or Freenulum. Ala Lobuli Centralis.
A nterior Semilimar or Crescentic Lobe. Posterior Semihmar or
Crescentic Lobe.
Superior Semilunar or Posterior Superior Lobe.
On the lower surface of the Worm, from before backward 4, the —
Nodule. Uvula. Pyramid. Tuber Valvula.
On the lower surface of the Hemispheres, from within outward 5, the — •
Flocculus (5). Tonsil or Amygdala (4). Biventral Lobe (3).
Cradle or Slender Lobe (3). Inferior Semilunar Lobe (3).
White Matter (Corpus Medullare) of the Cerebellum includes the
peduncular fibres and the fibres proper. The former are projection fibres
and are arranged in 3 peduncles on each side, which arise from the anterior
part of the hemispheres, and connect the cerebellum with itself and with
the rest of the brain, as follows: —
Superior Peduncles (brachia conjunctiva), — in part form the roof of
the 4th ventricle; they pass from the corpus dentatum under the
corpora quadrigemina, below which their fibres decussate, going to
the red nucleus of the tegmentum, and by a relay through the optic
thalamus to the cerebral cortex. Stretching from one peduncle to
the other is the —
Valve of Vieussens, or Superior Medullary Velum (see page 203), — a
thin lamina of white matter, which with the superior peduncles forms
part of the roof of the 4th ventricle (see page 211).
Middle Peduncles (brachia pontis) (8), — comprise most of the transverse
fibres of the pons, and are chiefly commissural fibres connecting the
cerebellar hemispheres with each other. All are connected with the
nucleus pontis of the same or the opposite side, those that are not
commissural are the continuation of the cortico-pontine tracts (see
page 197).
Inferior Peduncles (corpora restiformes), — connect the cerebellum
with the medulla oblongata.
Fibra Proprice, the proper fibres of the cerebellum, — are of 2 kinds; the
208 HUMAN ANATOMY
commissural, connecting the hemispheres, and the association or
arcuate fibres, connecting adjacent laminae.
Cortical Gray Matter (Substantia Corticalis) of the Cerebellum is
situated on the surface, forming the cortex, a section of which presents a
characteristic foliated appearance, named the Arbor Vita, due to the
branching of the laminae given off from the central white matter to the
cortical portion. The gray matter of the cortex consists of three layers,
as follows:
Molecular or External Gray Layer, — consists of fibres and cells.
Middle Layer Containing the Cells of Purkinje, (the characteristic cells
of the cerebellum), an incomplete stratum of flask-shaped cells, their
bases resting on the granular layer, their necks giving off numerous
dendrites to the molecular layer.
Granular or Internal rust-colored Layer of Turner, — contains numerous
small nerve-cells or granules of reddish-brown color, also many nerve-
fibrils, among which are the axones of the Purkinje cells. This layer
also contains larger cells, known as the Golgi cells, situated in its outer
part.
Central Gray Matter of the Cerebellum is disposed on each side in 4
centres, one of which, the dentate nucleus is large; the others being of small
size. They are situated in the middle of the white matter of the organ, and
are as follows: the —
Dentate Nucleus, or Ganglion of the Cerebellum, — an irregularly folded
lamina of gray matter, having an opening anteriorly, the hilum, from
which emerge most of the fibres of the superior peduncle (brachium
conjunct! vum.)
Nucleus Emboliformis, — lies to the inner side of the dentate nucleus,
partly covering its hilum. It is probably part of the dentate nucleus.
Nucleus Globosus, — an elongated mass on the inner side of the preceding.
Nucleus Fastigii, or Roof Nucleus of Stilling, — is close to the middle line
at the anterior end of the vermiform process (vermis) and imme-
diately over the roof of the 4th ventricle. The fibres of the ves-
tibular nerve terminate in this nucleus after having decussated in the
vermis.
THE MEDULLA OBLONGATA
The Medulla Oblongata, or Myelencephalon, formerly called the Spinal
Bulb, is thelowermost division of the brain and is continuous with the spinal
cord. It extends from the lower margin of the pons Varolii (5) to the
inferior pyramidal (motor) decussation (12) corresponding to the lower mar-
gin of the foramen magnum. Its ventral surface rests on the basilar
THE BRAIN 209
groove of the occipital bone, its dorsal surface is in the fossa between the
cerebellar hemispheres. It is i inch long, % inch broad above, and ^ inch
thick; and of pyramidal form, its broad end upward. On its surface are
the anterior and posterior median fissures; the former terminating just
below the pons in a cul-de-sac, the foramen ccecum; the latter expanding
into the 4th ventricle about the middle of the medulla. On each side the
medulla presents the following parts: —
Pyramid (7), — a bundle of white matter alongside the anterior median
fissure, formed by the upward continuation of the direct tract (fas-
ciculus cerebro-spinalis anterior) of the anterior column (funiculus
anterior) and the crossed tract (fasciculus cerebro-spinalis lateralis)
of the lateral column (funiculus lateralis) of the spinal cord. As the
latter tract ascends it decussates with its fellow of the opposite side
across the fissure, forming the inferior decussalion of the pyramids
(8). Each pyramid is bounded by the antero-lateral sulcus which is
continuous with that of the cord.
Olive (Olivary Body) (9), — an ovoid projection on the outer side of the
pyramid and immediately below the pons. In the groove between the
olive and pyramid, the hypoglossal nerve fibres (27) emerge; in that
between the olive and restiform body (inferior cerebellar peduncle)
emerge the glosso-pharyngeal
(24), pneumogastric (n. vagus)
(25) and spinal accessory (n.
accessorius) (26) nerves. The
Inferior Olivary Nucleus or corpus
denlatum is a thin, wavy lamina
of gray matter, open at its upper
and inner part. Three accessory
nuclei (dorsal, medial and
lateral) are also situated in the
olive.
Fasciculus of Rolando (10), — a
slight, longitudinal prominence
on the outer side of the olivary
body. It corresponds to a mass
of gray matter, substanlia gelatinosa, continuous with the posterior
horn of the gray matter of the cord.
Lateral Column, — hidden above by the olivary body but showing below
it; is the continuation of the lateral column (funiculus lateralis) of
the cord in part.
Restiform Body (inferior cerebellar peduncle), — between the lateral
14
210 HUMAN ANATOMY
column and the fasciculus cuneatus; contains the arcuate fibres,
external and internal, and the dorsal spino-csr Cellar fasciculus (direct
cerebellar tract). The two restiform bodies diverge as they ascend,
assist in forming the lateral walls of the 4th ventricle, and enter the
cerebellar hemispheres as the inferior peduncles of the cerebellum.
Dorsal S pino-cerebellar Fasciculus (direct cerebellar tract of Flechsig),
— arises from cells in the dorsal nucleus (Clark's column) which occu-
pies the base (cervix) of the posterior horn (columna posterior) of
the cord from the level of the 3d lumbar to that of the 7th cervical
nerve. The axones arising in these cells pass to the dorso-lateral
periphery of the lateral column (funiculus lateralis) up which they
continue until they reach the medulla, then they run up behind the
origins of the Qth, loth and nth cranial nerves, and then bend out-
wards and forwards, entering the restiform body (inferior cerebellar
peduncle) in which they continue to the cells in the cortex of the
cerebellar hemisphere of th2 same side as that of their origin.
External or Superficial Arcuate Fibres, are in two sets. The anterior set
of fibres are the more numerous, they arise from cells in the nucleus
gracilis and nucleus cuneatus, run forwards, and decussate in the medial
raphe, emerge in the anterior medial fissure and run outwards across
the surface of the pyramid and lower part of the olive, then turn
upwards and enter the restiform body (inferior cerebellar peduncle) of
the side opposite to that of their origin.
The posterior set of fibres also arise from the cells in the cuneate and
gracile nuclei; they run outwards, forwards, and upwards directly into
the restiform body (inferior cerebellar peduncle) of the same side as
that of their origin.
Internal or Deep Arcuate Fibres form an intricate network situated
between the olives and behind the pyramids. Some of these fibres,
the olivo-cerebellar and cerebello-olivary :, enter the restiform body (infe-
rior cerebellar peduncle) . The remaining fibres are association or com-
missural fibres connected with the nuclear cells in the formatio
reticularis of the tegmentum and the nuclei of the sensory cranial
nerves.
Fasciculus Cuneatus, — between the restiform body and the funiculus
gracilis; is the continuation of the postero-lateral column of the cord
(see lateral lemniscus, page 198).
Fasciculus Gracilis (posterior pyramid), — a narrow, white band, parallel
to and alongside the posterior fissure; is the continuation of the pos-
tero-median column of the cord. Its enlarged upper extremity is
club-shaped and called the clava (see lateral lemniscus, page 198).
THE BRAIN 211
Other Structures in the Medulla. Internally the medulla is composed
of longitudinal bundles of nerve-fibres, masses of gray matter constituting
nerve nuclei, and nerve-fibres originating from the nuclei. The —
Independent Nuclei, — are those of the 5th, 8th, gih, loth, nth and i2th
cranial nerves, which arise in or near the floor of the 4th ventricle;
also the nucleus of the fasciculus teres (eminentia medialis or teres),
that of the olivary body, the accessory olivary nuclei, and the tractus
solitarius or trineural tract, the ascending root of the gth nerve.
Raphe or Medial Septum, — is situated in the middle line of the medulla
above the decussation of the pyramids, and consists of fibres having
different directions and of multipolar nerve-cells.
Formatio Reticularis, — is a coarse network, situated within the anterior
and lateral regions of t^e medulla, and is formed by the breaking up of
the anterior gray matter by the white fibres of the crossed pyramidal
(cerebro-spinal) tracts.
The Fourth Ventricle, or Ventricle of the Cerebellum, is a diamond-
shaped cavity lying between the cerebellum and the posterior surface of
the pons Varolii and medulla oblongata. Its upper angle is on a level with
the upper border of the pons, it corresponds with the lower opening of the
cerebral aqueduct of Sylvius, by which this ventricle communicates with the
3d ventricle. Its lower angle is on a level with the lower border of the
olivary body (oliva), it is continuous with the central canal of the spinal
cord, and is called the calamus scriptorius, from its resemblance to the
point of a pen. The ventricle is closed posteriorly by a layer of pia mater,
the tela choroidea inferior, with its choroid plexuses, in which layer are 3
openings; the foramen of Magendie (metapore), just above the calamus
scriptorius in the median line, and the foramina of Key and Retzius at the
extremities of the lateral angles. Through these foramina the ventricles of
the brain communicate with the subarachnoid space of the brain and
spinal cord. The fourth ventricle is bounded as follows: —
Roof, — is tent-shaped and formed by superior peduncles of the cere-
bellum, the superior medullary velum or valve of Vieussens, the tela
choroidea inferior (see above) and its choroid plexus, the obex, and the
inferior medullary velum.
Floor, — is formed by the posterior surface of the pons above and the
medulla below. It contains the median furrow, on each side of which
are — the fasciculus teres (eminentia medialis or colliculus facialis),
striae acusticae (striae medullares), conductor sonorus (striae obliquae),
fovea superior, fovea inferior, alacinerea, tuberculum acusticum, locus
caeruleus, taenia violacea, and the eminences of origin of certain nerves
(seepages 212 and 213).
212 HUMAN ANATOMY
Laterally, — in the upper part are the superior peduncles of the cere-
bellum; in the lower part, the inferior peduncles (restiform bodies)
fringed by the funiculi graciles, their clavae and the ligulae.
Parts named above, and heretofore undescribed, are the — •
Sulcus Longitudinalis Medianus, — the vertical median fissure; from the
centre of which on each side emerge the — •
Strife Medullares or Stria Acusticce, — white fibres crossing the floor of
the ventricle transversely, dividing it into two triangles, and passing
outward to the auditory nerve. They are the axons of the nerve-
cells of the tuberculum acusticum.
Conductor Sonorus (striae obliquae), — a whitish band of fibres in no way
differing from the striae medullares except that they run from the mid-
line obliquely outward and forward instead of transversely. They
are not constant.
Inferior Medullary Velum, — a thin layer of white matter, stretching over
the ventricle toward its lateral angles.
Obex and Lingula,—<are, respectively the inferior and superior parts of a
little irregular ridge, which runs from the clava of the funiculus gracilis
to its fellow of the opposite side.
Eminentia Teres (colliculus facialis), — the prominent centre of a spin-
dle-shaped eminence made by an underlying bundle of white fibres,
the fasciculus teres, formed in part by the fibres of the facial nerve.
Fovea Superior, — an angular depression, external to the fasciculus teres
and above the striae medullares.
Locus Cceruleus, — a bluish depressed area above the fovea superior.
Fovea Inferior, — an angular groove, its apex at the striae, its limbs diverg-
ing below, enclosing the —
Ala Cinerea or Trigonum Vagi, — a triangular area, corresponding with
the nuclei of the vagus and glosso-pharyngeal nerves.
Eminentia Cinerea, — a prominent elevation of the ala cinerea.
Trigonum Hypoglossi, — a triangular area, internal to the inner limb of
the fovea inferior, and corresponding to the tract of nerve-cells from
which the hypoglossal nerve originates.
Trigonum Acustici, — a triangular area, external to the outer side of the
fovea inferior, having at its base a prominence, the tuberculum
acusticum,
Nuclei of Origin, in the floor of the 4th Ventricle, comprise the nuclei of
the cranial nerves from the 5th to the i2th inclusive, also vaso-motor,
cardiac ancj respiratory centres, Near the ventricle, in the anterior wall
THE SPINAL CORD 21^
of the aqueduct of Sylvius, are the nuclei for the 3d and 4th nerves.
Those in the floor itself are as follows: —
$lh Nerve (trigeminus), — two groups of cells, extending the length of the
medulla and alongside the aqueduct of Sylvius, the nuclei lying close to
the lateral recesses of the ventricle.
6th Nerve (abducens), — in the upper part, close to the median line.
^th Nerve (facial), — below and external to the 6th.
8th Nerve (auditory), 2 nuclei, one beneath the striae, the other just
outside the ventricle.
gth Nerve (glosso-pharyngeal) and loth Nerve (vagus), — in the upper part
of the ala cinerea, near the inferior angle of the ventricle.
nth Nerve (spinal accessory), — below the preceding, in the lower part of
the ala cinerea, and running down into the cord as low as the 6th cer-
vical vertebra.
1 2th Nerve (hypoglossal) , — internal to the gth and loth beneath the
fasciculus teres, and in the trigonum hypoglossi.
THE SPINAL CORD (MEDULLA SPINALIS)
The Spinal Cord is that part of the cerebro-spinal axis which is situated in
the spinal canal. Its length is about 17 or 18 inches, terminating at the
lower border of the ist lumbar vertebra in thefilum terminate (16). It is
cylindrical in general form, with 2 enlargements, one in the cervical region,
the other in the lumbar. It is composed of gray and white matter, the
gray being inside (instead of outside, as in the cerebrum), and arranged so
as to present a crescentic appearance in horizontal section, joined by a
transverse commissure, and the extremities forming the Anterior and Pos-
terior Horns (columnae), from which regions respectively the anterior and
posterior roots of the spinal nerves have their apparent origin. The —
Membranes, — of the cord are 3, as in the brain: the dura mater, arach-
noid, and pia mater. The Dura Mater represents only the meningeal
or supporting layer of the cranial dura mater. It is not adherent to
the spinal column, but is connected thereto by fibrous tissue. The
Arachnoid is arranged as on the brain, its sub-arachnoid space being
filled with its fluid, for the protection of the cord. The Pia Mater has
a fibrous band on each side, the ligamentum denticulatum (9), con-
necting it to the dura mater by 21 serrations.
Fissures, — number 6, the anterior and posterior median, and on each
side the postero-lateral (n) and the posterior intermediate.
Columns (funiculi),— are 4 in number, 2 on each side of the cord; a
small posterior column, and a large antero-lateral column, separated
from each other by the postero-lateral fissure. The posterior col-
214
HUMAN ANATOMY
FIG. 75-
umn is further divided in its upper part, into a postero-median and a
postero-lateral column, which are separated from each other by the
posterior intermediate septum.
Central Canal, — a minute canal, barely visible to the naked eye, extends
the whole length of the cord, originating above
in the lower angle of the 4th ventricle (i) and
terminating below in a somewhat dilated
extremity.
White Substance of the Cord consists of medul-
lated fibres, mostly disposed longitudinally, but
some obliquely and transversely, also blood-vessels
and neuroglia. The Neuroglia supports the fibres
and cells of the gray substance as well as the fibres
of the white, and is accumulated in three situa-
tions; on the surface of the cord, beneath the pia
mater; around the central canal, as the substantia
gelatinosa centralis; as a cap over the posterior
horn of gray matter, forming the substantia cinerea
gelatinosa.
Nerve-tracts in the white substance of the cord,
shown by investigation of pathological lesions, as
extending along various portions of the cord and
into or from the brain, are 8 in number, as
follows: —
In the antero-lateral column (funiculus antero-
lateralis) are 6, the —
Direct Pyramidal Tract (fasciculus cerebro-
spinalis anterior), — next to the median fissure
and in the upper part of the cord; consists
of descending fibres from the motor area of
the cerebral cortex of the same side, passing
through the pyramid of the medulla, crossing in the anterior white
commissure of the cord, and disappearing about the middle of its
thoracic region (see page 196).
Crossed Pyramidal Tract (fasciculus cerebro-spinalis Jateralis), — in the
hinder part of the column; consists of descending fibres from the
motor area of the cortex on the opposite side, through the pyramid
of the medulla, crossing in the decussation of the pyramids (see
page 196).
Antero-lateral Ascending (Gower's) Tract (anterior spino-cerebellar
THE SPINAL CORD 215
fasciculus), — in the anterior part of the column; consists of ascending
fibres arising from cells in the posterior horn, crossing in the anterior
gray commissure, and passing upward through the medulla and pons
to the cerebellum through its superior peduncles (brachia conjunc-
tiva) (see page 205).
Direct Cerebellar Tract (dorsal spino-cerebellar fasciculus), — behind
the preceding, commencing in the lumbar region; consists of fibres
from cells in the posterior gray matter, ascending through the resti-
form body to the cerebellum (see page 210).
Tract of Lissaucr (fasciculus postero-lateralis) — a small tract, formed by
some of the fibres of the posterior roots of the spinal nerves, running
upward for a short distance and entering the posterior horn of gray
matter.
Antero-lateral Ground Bundle (fasciculus proprius anterior et fas-
ciculus proprius posterior), — is the remaining part of the column,
situated next to the gray matter of the cord; contains — longitudinal
association fibres, uniting cell-groups of the gray matter with each
other; fibres crossing the anterior commissure from the gray matter
of the opposite side; horizontal fibres belonging to the anterior roots of
the spinal nerves.
In the Posterior Column (funiculus posterior) are 2 tracts, the —
Tract of Goll (fasciculus gracilis), — next to the posterior fissure; con-
sists of fibres from the posterior roots of the spinal nerves, ascend-
ing to the medulla where they end in the nucleus gracilis (see page
198).
Tract of Burdach (fasciculus cuneatus), — between the preceding and
the gray matter; consists of fibres from the posterior roots of the spinal
nerves, some ascending a short distance and entering the gray matter,
others entering Coil's tract and passing to the medulla (see page
198).
Gray Substance of the Cord occupies the central portion, a transverse
section showing it in the form of two crescents joined by the gray commis-
sure (commissura grisea). Each crescent has an anterior and a posterior
cornu or horn (columna) ; a lateral horn being also seen in the upper thoracic
region. The gray substance consists of nerve-fibres, nerve-cells, blood-
vessels and connective tissue. The —
Nerve-fibres, — are found as a dense interlacement of minute fibrils,
formed of the axons and dendrons of the nerve-cells and nerves of
larger size.
Nerve-cells* — some form columns of cells placed longitudinally, and
some are scattered throughout the gray matter.
2l6
HUMAN ANATOMY
FIG. 76.
Clarke's Posterior Vesicular Column (nucleus dorsalis), — is a group of
nerve-cells at the base of the posterior horn on its inner side, extend-
ing from the yth cervical nerve to the 3d lumbar.
The Spinal Nerves are transmitted from each
side of the spinal cord through the intervertebral
foramina of the spinal column, in 31 pairs, of
which the cervical number 8, the thoracic 12, the
lumbar 5, the sacral 5, and the coccygeal i.
Each nerve arises by two roots; an anterior (13)
or motor root, and a posterior (10) or sensory
root, the latter being distinguished by a ganglion,
the spinal ganglion (12). These nerves are de-
scribed separately infra, after the description of
the cranial nerves. The —
Cauda Equina (ly) (horse's tail), — is a sheaf of
nerves composed of the elongated roots of
the 4 upper sacral nerves, passing downward
to reach their respective foramina of exit
from the spinal canal.
THE CRANIAL NERVES (NERVI
CEREBRALES)
The Cranial Nerves number 12 pairs, those
from the 5th to the i2th inclusive having their
deep origin wholly or in part from the floor of the
4th ventricle, and all, except the first two, origi-
nating in or near that situation. Their super-
ficial or apparent origin is their connection with
the surface of the brain, their deep or real origin lies
in some special nucleus of gray matter deeply
situated in the brain. After emerging from the surface the nerves pass
through tubular prolongations of the dura mater in various foramina at
the base of the skull, to their final distribution.
1st Nerve, Olfactory (n. olfactorius) (Plate 6), nerves of smell (fila),
about 20 in number, composed of non-medullated fibres, — arise from the
under surface of the olfactory bulb (see page 188); deeply by 2 white roots,
the medial root from the area of J3roca and the ^callosal and sub-callosal
gyrus; the lateral root from the anterior perforated space (substantia
perforata anterior) and from the union of the temporal and uncinate gyri,
THE CRANIAL NERVES
217
and by the middle gray root (trigonum olfactorium) from thej3ptic thala-
by numerous foramina in the cribriform plate of the ethmoid
bone; to form a plexiform network over the upper third of the nasal septum,
the superior turbinal process and the adjacent surface of the ethmoid
bone, from which branches are distributed to the Schneiderian membrane
of the nose.
2d Nerve, Optic (n. opticus) nerve of sight (Plate 6), — arises from the
optic commissure (chiasma opticum) (16) and tracts (15); deeply from the
external geniculate body (corpus
geniculatum laterale), the pulvinar
of the ojytk: thalamus, and the upper
quadrigi-minal body (colliculus su-
perior) these being the lower visual
centres; also from the^neate and
lingual lobules of the occipital lobe
(cortical visual centres); exit by the
optic foramen; to the retina of the
eye. [This nerve and the optic tract
are more fully described under the
sub-title Nerves of the Eye.]
20.
3d Nerve, Motor Oculi (n. oculo-
motorius) (Plate 6), motor nerve of
the eye-ball,-^omes from the inner
side of the crus (peduncle) cerebri
(17), in front of the pons (5); deeply
from a nucleus in the floor of the
aqueduct of Sylvius (aquaeductus
cerebri) ; exit by the sphenoidal (su-
perior orbital) fissure; to all the mus-
cles of the orbit except the superior
oblique and external rectus, also
through the ciliary ganglion to the sphincter of the iris and the ciliary
muscle.
4th Nerve, Trochlear or Pathetic (n. trochlearis) (Plate 6), motor of
the eye-ball, — arises from the outer side of the crus (jpeduncle) cerebri (18),
in front of the pons; deeply from a nucleus in the floor of the aqueduct of
.Sylvius, below that of the 3d nerve decussates in the superior medullary
velum with its companion nerve \jgU • by the sphenoidal (superior orbital)
fissure; to the superior oblique (trochlear) muscle of the eye-ball of the side
opposite to that of its origin.
218
HUMAN ANATOMY
5th Nerve, Trifacial or (n. trigeminus) (Plate 7), nerve of sensation
and motion, — arises by 2 roots (19) from the side of the pons Varolii; deeply
from a nerve-tract in the medulla oblongata and the locu^caeruleus (sen-
sory root), the floor of the 4th ventricle and the wall of the cerebral aque-
duct of Sylvius (motor root or masti-
cator nerve); exit in 3 divisions by
the sphenoidal fissure, the foramen
rotundum and the foramen ovale
respectively. The Gasscrian or semi-
lunar ganglion (5) is situated on its
sensory root at the origin of the
three divisions. This nerve resem-
bles a spinal nerve in arising by two
roots, in having a ganglion on its pos-
terior (sensory) root, and in its com-
pound function. It is the great sen-
sory nerve of the head and face,
and the motor nerve of the muscles
of mastication. Its divisions are
the ophthalmic, the maxillary and
the mandibular as follows: —
OPHTHALMIC (n. ophtf almicus)
(6), a sensory nerve, — exit by the
sphenoidal (superior orbital) fissure;
to the eye-ball, lacrimal gland, mu-
cous lining of the eye and nasal fossae, and the skin of the forehead, eye-
brow and nose. Its branches are the —
Frontal (9)
Nasal (n)
or naso-
ciliary
f Supra-orbital.
\ Supra-trochlear. Lacrimal (10)
Branches to the gland,
the conjunctiva, and
the eyelid.
Ganglionic, to the ciliary ganglion.
Ciliary, to the ciliary muscles, iris and cornea.
Infra-trochlear, to the skin of the eyelids and side of the
nose, the conjunctiva, lacrimal sac and caruncula
lacrimalis.
MAXILLARY (7), a sensory nerve, — exit by the foramen rotundum; to
the temple, cheek, lower eyelid, nose, lip, upper teeth and the spheno-
palatine ganglion, thence to the palate. Its branches are the —
THE CRANIAL NERVES 2IQ
Meningeal (n. meningeus medius).
f Temporal (ramus zygomaticotem-
Orbital (n. zygomaticus) (20) ( poralis).
[ Malar (ramus zygomaticofacialis).
2 Spheno- palatine (nn. sphenopalatini).
2 Posterior Sup. Dental (16) (rami alveolares superiores posteriores).
Middle Superior Dental (ramus alveolaris superior medius).
Anterior Sup. Dental (18) (ramus alveolaris superior anterior).
Palpebral (rami palpebrales inferiores).
Nasal (rami nasales interni).
Labial (rami labiales superiores).
MANDIBULAR (8), includes the masticator nerve or motor root of the 5th,
and is a nerve of motion, common sensation and special sense (taste). Its
exit is by the foramen ovale. Its recurrent branch goes to the dura
mater and the lining of the mastoid cells; its motor filaments to the muscles
of mastication; its sensory ones to the teeth and gums of the lower jaw, the
skin of the temple and external ear, the lower face and lip, and the anterior
% of the tongue. Its branches are the —
Recurrent or meningeal (n. spinosus).
Internal Pterygoid (masticator).
Masseteric (masticator). Auriculo-tem-
Deep Temporal 2 (masticator), poral (26)
Buccal (n. buccinatorius).
External Pterygoid (masticator).
Br. to the facial nerve.
Br. to otic ganglion.
Ant. Auricular 2.
Brs. to meatus auditorius 2
Articular.
Parotid.
Superior Temporal.
Lingual or Gustatory (23), — to the tongue, mouth, gums and sub-lingual
gland: communicates with the facial, inferior dental and hypoglossal
nerves and the sub-mandibular ganglion.
I Mylo-hyoid (masticator) (28), to that muscle
Inferior alveolar or and digastric.
Dental (24) { Dental Brs. to the molar and bicuspid teeth.
Incisive, to the canine and incisor teeth.
Mental (25), to the chin and lower lip.
6th Nerve, Abducent (n. abducens) (Plate 10), motor of the eyeball, —
arises from the pyramid of the medulla oblongata, close to the pons (20, Fig.
76); deeply from the floor of the 4th ventricle, beneath the eminentia teres;
exit by the sphenoidal (superior orbital) fissure; to the external rectus
muscle of the eyeball.
22O HUMAN ANATOMY
yth Nerve, Facial, Portio Dura (n. facialis) (Plate 8), is the motor nerve
of the face, the stapedius, the muscles of the external ear and other mus-
cles. The Pars intermedia (glosso-palatine nerve) is a sensory nerve to the
palate and its chorda tympani branch is the nerve of taste for the anterior
2a of the tongue, and the vaso-dilator of the sub-mandibular and sub-
lingual glands. Cashes, from the upper part of the medulla oblongata, in
the groove between the olivary and restiform bodies (21, Fig. 76) ; deeply in
the floor of the 4th ventricle, from a nucleus in the lower part of the pons
near that of the 6th nerve; the Pars Intermedia takes its deep origin from
the Solitary Tract; exit by the internal auditory meatus, through the
aqusductus (canalis facialis) Fallopii and the stylo-mastoid foramen; to
the muscles of expression of the face, those of the ear, etc., and to the
tongue. Behind the ramus of the jaw its diverging branches form the pes
anserinus or goose's foot. It communicates with the meningeal sympa-
thetic plexus by the external superficial petrosal nerve; with the spheno-
palatine and otic ganglia, by the large and small superficial petrosal nerves ;
with the auditory, great auricular, auriculo-temporal, pneumogastric (n.
vagus), glosso-pharyngeal, small occipital, and superficial cervical nerves,
the three divisions of the 5th nerve, and the carotid plexus. The petrosal
nerves mentioned above are given off by the geniculate ganglion, a swelling
on the ;th nerve in the aquaeductus (canalis facialis) Fallopii (described
separately). Its branches of distribution are the —
Tympanic, — to the stapedius muscle.
Chorda Tympani, — nerve of taste, etc. (see above).
Posterior Auricular, — dividing into Auricular and Occipital.
Digastric, — to that muscle.
Stylo-hyoid, — to that muscle.
j Temporal Brs. to the temporal region.
Temporo-facial { Malar Brs. to the occip.-frontalis and the lower eyelid.
[ Infra-orbital / Superficial Brs.
\ Deep Brs.
{Buccal Brs. to the mouth and cheek muscles.
Mandibular Brs.
Cervical Brs.
8th Nerve, Auditory, Portio Mollis (n. acusticus) (Plate 10), the special
nerve of the sense of hearing, is soft in texture and destitute of neurilemma.
-arises from the groove between the pons and medulla, between the resti-
form body and the 7th nerve (22, Fig. 76); deeply from thejSflQr of the ^th
ventricle by 2 roots, one from the trigonum acustici, the other from the ac-
THE CRANIAL NERVES 221
cessory nucleus and the tuberculum acusticum. Goes by the internal
auditory meatus; to the internal ear. It is the only cranial nerve which
does not leave the cranium. Its branches are two, the —
Vestibular, to the vestibule. Qochlear, to the cochlea (see page 309).
2J* j 9th Nerve, Glosso-pharyngeal (n. glosso-pharyngeus) (Plate 9) ^sensory
* nerveTand nerve of taste, — arises by 3 or 4 filaments from the medulla
oblongata in the groove between the olivary and restiform bodies (24, Fig.
76); deeply from a nucleus in the floor of the 4th ventricle and the tractus
or fasciculus solitarius in the lower part of the medulla; exit by the jugular
.foramen; to the mucous membrane of the fauces and base of the tongue,
and the mucous glands of the mouth and tonsil. It communicates with the
facial, pneumogastric (vagus) and sympathetic nerves. Its branches of
distribution are the —
Tympanic or Jacobson's Nerve, — described under Ear (see page 302).
Carotid Branches, — along the internal carotid artery.
Pharyngeal, — to the pharyngeal plexus.
Muscular, — to the stylo-pharyngeus muscle.
Tonsillar Branches, — forming the tonsillar plexus, thence to the soft
palate and fauces.
Lingjiql 2,— one to the base, the other to the posterior half of the tongue,
being distributed to the mucous membrane, the papillae and the fol-
licular glands.
loth Nerve, Pneumogastric (n. vagus) (Plate 9), — the auriculo-laryngo-
pharyngo-cesophago-tracheo-pulmono-cardio-gastro-hepatic nerve (Pan-
• coast), is composed of both motor and^ensory fibres. It arises by 8 or 10
filaments from the medulla oblongata (25, Fig. 76) , between the olivary and
restiform bodies; deeply from the nucleus vagi in the floor of the 4th ven-
tricle, the tractus or fasciculus solitarius and the nucleus ambiguus in the
medulla; exit by the jugular foramen; and is distributed to the parts and
organs named in the afjove euphonious appellation; supplying sensory and
motor fibres to the organs of voice and respiration, and motor fibres alone
to the pharynx, cesophagus, stomach and heart. It has a ganglion on its
root and another on its trunk, thereby communicating with the 7th, gth,
nth and i2th cranial nerves, the ist and 2nd cervical nerves and the sym-
pathetic. Its branches of distribution are the—
Meningeal (ramus meningeus), — a recurrent filament to the dura mater.
Auricular (ramus auricularis) or Arnold's Nerve, — to the external ear.
Pharyngeal (ramus pharyngeus), — to the pharyngeal plexus.
Superior Laryngeal (n. laryngeus superior), — a nerve of sensation to the
larynx, dividing into the External (ramus externus) and Internal
(ramus internus) Laryngeal.
222 HUMAN ANATOMY
Recurrent Laryngeal (n. laryngeus inferior), — the motor nerve of the
larynx; gives off cesophageal, tracheal and pharyngeal branches.
Cervical Cardiac Branches (rami cardiaci superiores), — to the cardiac
plexuses.
Thoracic Cardiac Branches (rami cardiaci inferiores), — 10 the deep car-
diac plexus.
Anterior Pulmonary Branches, — to that plexus.
Posterior Pulmonary Branches, — to that plexus.
(Esophageal Branches (rami cesophagei), — to the cesophageal plexus.
Gastric (rami gastric), — on the left side to the anterior surface of the
stomach, on the right side to the posterior surface; some filaments
going to the hepatic plexus.
i ith Nerve, Spinal Accessory (n. accessorious) (Plate 9), a motor nerve;
consists of the two parts, the accessory (ramus internus) to the vagus and
the spinal portion (ramus externus). The Accessory or Bulbar portion
(ramus internus) arises by 4 or 5 filaments from the medulla below the
vagus (26, Fig. 76); deeply from the nucleus ambiguus and the column
of cells underneath the ala cineria in the floor of the 4th ventricle; exit
by the jugular foramen; to the pharyngeal and superior laryngeal branches
of the vagus and through the former probably supplying the muscles of
the soft palate. The Spinal portion (ramus externus) arises by several
filaments from the lateral tract of the cord behind the anterior roots of the
upper five cervical spinal nerves; deeply from the dorso-lateral gray tract
of the cord from the olive down to the level of the 5th cervical nerve; exit
by the jugular foramen, having first entered the skull by the foramen mag-
num; to the sterno-mastoid and trapezius muscles, forming plexuses with
the 2d, 3d and 4th cervical nerves.
1 2th Nerve, Hypoglossal (n. hypoglossus), Nonus or Ninth of Willis
(Plate 10), the motor nerve of the tongue, — arises by 10 to 15 filaments
from the medulla oblongata in the groove between the pyramid and the
olivary body (2 7, Fig. 76); deeply from the trigonum hypoglossi in the floor
of the 4th ventricle; exit by the anterior condylar foramen (canalis hypo-
glossi) in two bundles; to certain muscles of the tongue and other muscles;
communicating with the vagus, sympathetic, ist and 2d cervical and the
lingual. Its branches of distribution are the —
Meningeal Branches, — to the dura mater.
Descendens Hypoglossi (ramus descendens), — to the sterno-hyoid,
sterno-thyroid and omohyoid muscles; joins the communicans hypo-
glossi branch of the cervical plexus.
Thyro-hyoid (ramus thyreohyoideus), — to the thyro-hyoid muscle.
GANGLIA OF CRANIAL NERVES 223
Muscular Branches, — to the stylo-glossus, hyo-glossus, genio-hyoid and
genio-hyo-glossus muscles, and to the intrinsic muscles of the tongue
(rami linguales).
Nerves entering the Cranium before passing out of it, are the spinal
portion (ramus externus) of the spinal Accessory (n. accessorius), and the
Nasal branch (n. nasociliaris) of the Ophthalmic division of the 5th nerve.
The first enters by the foramen magnum, and leaves by the jugular fora-
men. The second enters from the orbit by the anterior ethmoidal fora-
men (canalis ethmoidale anterius), and leaves by the nasal slit at the side
of the crista galli.
GANGLIA OF THE CRANIAL NERVES
Ganglia are on and connected with several of the cranial nerves. Those
connected with the 5th nerve have each motor, sensory and sympathetic
roots. The various ganglia are named and connected as follows: —
With the $d Nerve, — the ophthalmic, lenticular, or ciliary ganglion (gan-
glion ciliare).
On the Fifth Nerve, — the Gasserian or semilunar ganglion.
With the 5/A Nerve, — the ophthalmic (ganglion ciliare), the spheno-
palatine (Meckel's), the otic, and the sub-mandibular or sub-maxil-
lary ganglia.
On the ith Nerve, — the geniculate ganglion (ganglion geniculi) or intu-
mescentia ganglioformis.
With the ith Nerve, — the spheno-palatine (Meckel's) ganglion, and the
otic ganglion.
With the Cochlear portion (radix cochlearis] of the 8th Nerve, — the spiral
ganglion.
With the Vestibular portion (radix vestibularis] of the &th Nerve, — the
vestibular ganglion (Scarpa's).
On the Qth Nerve, — the jugular (ganglion superius) and petrous (ganglion
inferius) ganglia.
On the loth Nerve, — the jugular or ganglion of the root (ganglion
jugulare), and the inferior or ganglion of the trunk (ganglion nodo-
sum).
With the nth Nerve, — the jugular ganglion (ganglion jugulare) of the
loth nerve is connected with the accessory portion (ramus internus)
of the nth.
Gasserian or Semilunar Ganglion (Plate 7), on the sensory root of the
5th nerve, is situated near the apex of the petrous portion of the temporal
bone. It communicates with the carotid plexus of the sympathetic by
filaments on its inner side. Its branches are the 3 divisions of the sth
224 HUMAN ANATOMY
nerve, the ophthalmic, maxillary, and mandibular, the latter trunk being
joined by the motor root (masticator nerve) of the nerve outside the cra-
nium. The ganglion also gives off minute branches to the tentorium
cerebelli and the dura mater in the middle cranial fossa.
Ophthalmic, Ciliary, or Lenticular Ganglion (ganglion ciliare) (Plate
6), is about the size of a pin's .head, and is situated at the back of the
orbit. Its roots are 3 in number, — a sensory (radix longa ganglii ciliaris),
from the nasal branch (n. nasociliaris) of the ophthalmic; a motor root
(radix brevis ganglii ciliaris), from the 3d nerve; and a sympathetic root
(radix sympathetica ganglii ciliaris), from the cavernous plexus. Its
branches are the short ciliary nerves (nn. ciliares breves), to the ciliary
muscle, the iris and the cornea.
^3¥
Spheno-palatine or Meckel's Ganglion (Plate 7), the largest of the
cranial ganglia, is situated in the spheno-palatine or pterygo-maxillary
fossa, close to the spheno-palatine foramen. Its roots are — a sensory,
from the maxillary nerve; a motor, from the facial, through the large
superficial petrosal (n. petrosus superficialis major); and a sympathetic
root, from the carotid plexus, through the large deep petrosal (n. petrosus
profundus); the two last-named joining to form the Vidian nerve (n.
canalis pterygoidei) before entering the ganglion. Its branches are the —
Ascending Branches (rami orbitales), — to the orbit.
Anterior or Large Palatine (n. palatinus anterior), — to the gums and
hard palate.
Middle or External Palatine (n. palatinus medius), — to the uvula, tonsil
and soft palate.
Posterior or Small Palatine (n. palatinus posterior), — to the levator
palati and azygos uvulae muscles, the soft palate, tonsil and uvula.
Superior Nasal Branches (rami nasales posteriores superiores), — to the
mucous membrane of the superior and middle turbinal processes and
that lining the posterior ethmoidal cells.
Naso-palatine (n. nasopalatinus), — to the mucous membrane behind
the incisor teeth, and that of the septum of the nose.
Pharyngeal or Ptery go- palatine, — to the mucous membrane of the upper
part of the pharynx.
Posterior Nasal Branches (rami nasales posteriores inferiores), — to
the mucous membrane at the back of the roof of the mouth, and
that of the septum and superior meatus of the nose.
Otic Ganglion (ganglion oticum), Arnold's (Plate 7), is situated on the
inner surface of the mandibular nerve, immediately below the fora-
men ovale. Its roots are — a sensory, from probably the glosso-pharyngeal;
GANGLIA OF CRANIAL NERVES 225
a motor, from probably the facial; both through the small superficial
petrosal (n; petrosus superficial minor) continued from the tympanic
plexus; and a sympathetic root from the middle meningeal plexus. It
communicates also with the internal pterygoid branch of the mandibular,
and with the auriculo-temporal. Its branches are — a filament (n. tensoris
tympani) to the tensor tympani muscle, one (n. tensoris veli palatini) to
the tensor palati, and one to the chorda tympani nerve.
Sub -mandibular or Sub-maxillary Ganglion (Plate 7) is situated above
the sub-maxillary gland. Its roots are — a sensory (rami communicantes
cum n. linguali), from the lingual branch of the mandibular; a motor,
from the facial by the chorda tympani; and a sympathetic root from the
facial plexus. Its branches (rami sub-
maxillares) are 5 or 6 in number, dis- IG> 79>
tributed to the mucous membrane of
the mouth, Wharton's duct (ductus
sub-maxillaris), and thesub-mandibular
or sub-maxillary gland.
Geniculate Ganglion (ganglion gen-
iculi) (2) or Intumescentia Ganglio-
formis (Plate 8), is a reddish, gangli-
form swelling on the yth or facial
nerve, situated in the aquasductus
Fallopii (canalis facialis), above the
tympanum and near the Gasserian
ganglion (ganglion semilunare). It
communicates with the spheno-pala-
tine ganglion, the otic ganglion and
the meningeal plexus of the sympathetic, by the 3 superficial petrosal
nerves, which are seen on removing the Gasserian ganglion (ganglion semi-
lunare) (7), as follows: —
Large Superficial Petrosal (3), — passes through the hiatus Fallopii
(hiatus canalis facialis), thence across the foramen lacerum medium
to the Vidian canal (canalis pterygoidei) where it joins the large deep
petrosal from the carotid plexus, to form the Vidian nerve (n. canalis
pterygoidei), as which it goes to Meckel's ganglion (ganglion spheno-
palatinum) (page 224), forming its motor root.
Small Superficial Petrosal (4), — immediately external to the preceding,
going from the geniculate ganglion of the yth to the otic ganglion,
lying directly over the tensor tympani muscle.
External Superficial Petrosal (5), — going from the 7th nerve to the
sympathetic plexus on the middle meningeal artery (6).
IS
226 HUMAN ANATOMY
The Vidian Nerve (n. canalis pterygoidei) (Plate 8), is a short nerve
of communication, between the facial and sympathetic on the one hand,
and the spheno-palatine ganglion on the other, supplying that ganglion
with its motor and vaso-motor roots. It is formed by the junction of
the—
Large Superficial Petrosal, br. of the facial (p. 220), with the —
Large Deep Petrosal, br. of the carotid plexus (p. 237), which tunnels the
cartilage filling in the foramen lacerum medium (p. 41). It then en-
ters the Vidian canal (canalis pterygoidei) (p. 25) in the pterygoid
process of the sphenoid bone, passing through which it finally joins
the posterior part of the spheno-palatine ganglion (p. 224).
Ganglia of the pth Nerve (Plate 9). The Jugular Ganglion (ganglion
superius) is regarded as a segmentation from the petrous ganglion (gan-
glion inferius) below. The Petrous Ganglion (ganglion inferius) is situated
in a depression on the lower border of the petrous portion of the temporal
bone. From it arise the filaments which connect the gth nerve with the
loth and the sympathetic; and it communicates also with the yth nerve.
Its branches of distribution are the tympanic, carotid, pharyngeal, muscu-
lar, torisillar, and lingual branches of the gth nerve (see page 221).
Ganglia of the loth Nerve (Plate 9). The Ganglion of the Root (gan-
glion jugulare) is connected by filaments with the accessory portion
(ramus internus) of the nth nerve, with the petrous (inferior) ganglion
of the 9th, with the yth, and with the sympathetic. The Ganglion of the
Trunk (ganglion nodosum) involves all the fibres of the nerve, as also the
accessory portion (ramus internus) of the nth, which passes through it.
It is connected with the 1 2th nerve, the superior cervical ganglion of the
sympathetic, and the loop between the ist and 2d cervical nerves.
THE SPINAL NERVES (NERVI SPINALES)
The Spinal Nerves number 31 pairs, of which the cervical number 8,
the thoracic 12, the lumbar 5, the sacral 5, and the coccygeal i. All the
cervical nerves escape above the corresponding vertebrae except the 8th
which emerges between the jth cervical and ist thoracic vertebrae, each
of the others below the corresponding vertebrae, through the intervertebral
foramina. Each nerve arises by 2 roots, — an anterior motor root (effer-
ent), and a posterior sensory one (afferent), the latter having a ganglion
on it, the spinal ganglion, situated in the intervertebral foramen. The
roots unite, and the spinal nerve thus formed divides into 2 divisions (rami),
each having motor and sensory fibres. Just before this division takes
THE SPINAL NERVES 227
place, each nerve gives off a minute gray ramus communicans, which
after being joined by a branch of the sympathetic, re-enters the spinal
canal and is distributed to the spinal cord (medulla spinalis) and its
meninges, these are called recurrent meningeal nerves. The posterior
divisions (rami) are small and generally unimportant; they supply the
muscles and integument of the back. The anterior divisions (rami)
supply the neck, front, and sides of the trunk, and the extremities; unit-
ing in various regions to form plexuses, from which important nerve-
trunks originate. Each anterior division (ramus), from 2d thoracic to 2d
lumbar inclusive, is connected by a slender filament with the sympathetic.
These are called splanchnic branches or "white rami communicantes ; there
is a second set of them given by the 2d and 3d or by the 3d and 4th sacral
nerves.
THE CERVICAL NERVES
The Cervical Nerves (Plate n), are 8 in number. The anterior divi-
sions of the 4 upper form the cervical plexus; the anterior divisions of the
lower 4, together with the ist thoracic, form the brachial plexus. The
posterior division (ramus) of the ist cervical, the suboccipital nerve,
differs from the others in not dividing into internal and external branches.
It gives off a communicating branch, to the second cervical, and 5 muscular
branches. The posterior division (ramus) of the 2d cervical is much
larger than the anterior, it is called the Great Occipital (n. occipitalis
magnus), a cutaneous nerve.
The Cervical Plexus (plexus cervicalis) (Plate n), is formed by the
anterior divisions of the upper 4 cervical nerves. It is situated opposite
the upper 4 cervical vertebrae, resting on the levator anguli scapulae (m.
levator scapulae) and scalenus medius muscles and covered in by the sterno-
mastoid. Its branches number 10, of which the first 4 are superficial and
the last 6 are deep, as follows:
Occipitalis Minor (n. occipitalis minimus), — ascending to the back of
the side of the head.
( Facial, to the skin over the parotid gland.
Auricularis Magnus \ Auricular, to the skin of the pinna, concha, etc.
I Mastoid, to the integument behind the ear.
Superficial Cervical (n. cutaneous colli), — by 2 branches to the skin of
the neck.
228 HUMAN ANATOMY
Supraclavicular
Suprasternal (nn. supraclaviculares anteriores), — to
the skin of that region.
Supraclavicular (nn. supraclaviculares medii), — to
the skin over the pectoral and deltoid.
Supra-acromial (nn. supraclaviculares posteriores), —
to the skin of the shoulder.
Communicating, — brs. to the loth (vagus), i2th (hypoglossal) and
sympathetic nerves.
Muscular, — to the anterior recti and rectus lateralis muscles.
Communicantes Hypoglossi 2, join the descendens hypoglossi nerve.
Phrenic, — is described below.
Deep Communicating, — to the spinal accessory nerve.
Deep Muscular, — to the sterno-mastoid, trapezius, levator anguli
- ^scapulas (m. levator scapulae) and scalenus medius muscles.
The Phrenic Nerve (nervus phrenicus), or Internal Respiratory of Bell,
arises by 3 heads from the 3d, 4th, and 5th cervical, descends across the
front of the scalenus anticus (m. scalenus anterior), crossing the sub-
clavian and internal mammary arteries in the middle mediastinum, and is
distributed to the inferior surface of the diaphragm. It sends filaments
to the pericardium and pleura, and communicates with the solar and
phrenic plexuses of the sympathetic in the abdomen. On the right side
of the body it is situated more deeply, and is shorter and more vertical in
direction than on the left side. In the thorax each phrenic nerve is
accompanied by the comes nervi phrenici artery, a branch of the internal
mammary.
The Brachial Plexus (plexus brachialis) (Plate 12), is formed by the
union of the anterior division of the four lower cervical nerves and the first
thoracic. The 5th, 6th and 7th cervical unite into one trunk externally
to the scalenus medius, as also do the 8th cervical and ist thoracic behind
the same muscle. Below the line of the clavicle both these trunks bifur-
cate; the two adjacent branches unite behind the axillary artery making
the Posterior Cord, and the remaining 2 form the Outer (lateral) and Inner
(medial) Cords, as referred to the artery. Each of these cords bifurcates,
but the 2 adjacent branches of the outer and inner cords unite over the
artery, to form the Median Nerve, leaving 4 other branches, — the Ulnar,
derived from the inner cord, iheMusculo-cutaneous (n. musculocutaneus),
from the outer cord, and the Musculo-spiral (n. radialis) and Circumflex
(n. axillaris) from the posterior cord. (See Plate 12.)
THE BRANCHES of the brachial plexus are as follows: —
Above the clavicle are given off 4, the —
THE SPINAL NERVES 2 29
/J Communicating, — completing the phrenic nerve.
* / Musctttar, to The longus colli, scaleni, rhomboidei, and subclavius
/ muscles. The branch actuating the rhombcidei and levator anguli
scapulae (n. levator scapulae) is sometimes called the posterior
. scapular (n. dorsalis scapulae).
/ Posterior, or Long Thoracic (n. thoracalis longus), external respiratory
' nerve of Bell, — -to the serratus magnus, arising from the 5th, 6th and
. 7th cervical.
/ Suprascapular, — from the ist trunk of the plexus, to the supra- and in-
fra-spinatus muscles and the shoulder-joint.
Below the clavicle are 12, namely, the —
/) Anterior Thoracic 2, — external (lateral) and internal (medial) from the
outer (lateral) and inner (medial) cords, to the pectoral muscles.
Subsca pular 3, — from the posterior cord, to the subscapularis, teres
major and latissimus dorsi muscles. The long sw&scapular is also
called nervus thoracodorsalis.
2, j Circumflex (n. axillaris), — from the posterior cord, to the muscles and
integument of the shoulder, and the shoulder-joint.
JMusculo-cutaneous (n. musculocutaneus), — from the outer cord, to
the forearm externally, piercing the coraco-brachialis muscle. Its
cutaneous branch is also called nervus cutaneus antibrachii lateralis.
' Internal Cutaneous (n. cutaneus antibrachii medialis), — from the inner
cord, to the arm and forearm.
Lesser Internal Cutaneous (n. cutaneus brachii medialis) nerve of Wris-
berg, — from the inner cord, to the back of the arm. Is sometimes
. wanting, sometimes connected with the intercosto-humeral.
V : Median (n. medianus), — from outer (lateral) and inner (medial) cords,
passes between the two heads of the pronator radii teres (m. pronator
teres), supplying the pronators, flexors, first 2 lumbricales, and the
integument of the thumb, 2^ fingers, and the radial side of the palm.
Its branches are all in the forearm, except its terminals in the palm of
the hand, and are named the —
Muscular.
Anterior Interosseous (n. interosseus antibrachii volaris).
Palmar Cutaneous (n. ramus cutaneus palmaris n. mediani).
. f Br. to thumb muscles.
\ Digital, (nn. digitales volares communes) to thumb and index.
J Digital (nn. digitales volares proprii) to thumb, and 2^
lntcrn.3,1 \ /.
( fingers.
Ulnar, — from the inner (medial) cord, passes between the two heads of
230 HUMAN ANATOMY
the flexor carpi ulnaris at the inner condyle of the humerus, supplying
the elbow- and wrist-joints, several muscles, and the palmar and dorsal
integument of the little finger and half of the ring finger. Branches
are the —
Articular (elbow). Dorsal Cutaneous. Superficial Palmar.
Muscular. Articular (wrist). Deep Palmar.
Cutaneous.
. I Musculo-spird (n. radialis), — from the posterior cord, accompanies the
/ superior profunda artery and vein in the spiral groove of the humerus,
and in front of the outer (lateral) condyle it divides into the radial
(ramus superficialis n. radialis) and posterior interosseous (ramus
prof undus n. radialis) nerves. Its branches are —
Muscular (rami musculares n. radialis) divided into internal (medial)
posterior, and external (lateral).
Cutaneous (rami collaterals n. radialis) one internal (n. cutaneus
brachii posterior) and two external (n. cutaneous brachii posterior,
ramus proximalis et ramus distalis).
Radial (ramus superficialis n. radialis) divides into an external and an
internal branch, the latter giving off 4 digital, to the ulnar side of the
thumb and the adjacent sides of 2^ fingers. Communicating branch
to ulnar (ramus anastomoticus ulnaris).
Posterior Interosseous (ramus prof undus n. radialis), supplies all the
muscles of the radial side and back of the arm, except 3, also the liga-
ments and articulations of the carpus.
TABLE OF THE CORDS OF THE BRACHIAL PLEXUS
Outer or Lateral Cord (superior)
Musculo-cutaneous (n. musculotaneus) . derivation 5, 6, C.
External (lateral) Anterior Thoracic derivation 5, 6, 7, C.
Outer (lateral) head of Median 'derivation 6, 7, C.
Inner or Medial Cord (inferior)
Inner (medial) head of median derivation 8, C. i, T.
Internal (medial) Anterior Thoracic.. . .derivation 8, C. i, T.
Internal Cutaneous (n. cutaneus anti-
brachii medialis) derivation 8, C. i, T.
Lesser Internal Cutaneous (n. cutaneus
brachii medialis) derivation i, T.
Ulnar derivation 8, C. i, T.
THE SPINAL NERVES 231
Posterior Cord
Upper Subscapular derivation 5, 6, C.
Long Subscapular (n. thoraco-dorsalis). derivation 5, 6, 7, C.
Lower Subscapular derivation 5, 6, C.
Circumflex (n. axillaris) derivation 5, 6, C.
Musculo-Spiral (n. radialis) derivation 5,6, 7,8.C. (i, 7\).
THE THORACIC NERVES (NERVI THORACALES)
The Thoracic Nerves (Plate 12) are 12 in number on each side. Their
posterior divisions pass backward beneath the transverse processes, and
divide into internal and external branches, supplying the muscles and in-
tegument of the back. Their anterior divisions, the intercostal nerves, are
distributed to the walls of the thorax and abdomen, separately from each
other, without plexiform arrangement. The upper 6, except the ist and
the intercosto-humeral (intercosto-brachial) branch of the 2d, are lim-
ited in their distribution to the parietes of the chest. The lower 6 supply
the walls of the chest and abdomen, the last one sending a cutaneous fila-
ment to the buttock. The Lateral Cutaneous nerves are derived from the
intercostals, midway between the vertebrae and the sternum; they pierce
the external intercostal and serratus magnus (m. serratus anterior) mus-
cles, and divide into anterior and posterior branches. Peculiar among the
thoracic nerves and their branches are the —
First Thoracic, — divides into 2 branches, one entering into the brachial
plexus, the other forming the ist intercostal nerve.
Intercosto-humeral (n. Intercostobrachialis), — is the lateral cutaneous
branch of the 2d intercostal (anterior division of the 2d thoracic); it
pierces the external intercostal muscle and crosses the axilla, joining
with a filament from the lesser internal cutaneous (n. cutaneus
brachii medialis) (nerve of Wrisberg), supplying the skin of the upper
half of the inside and back of the arm, and communicating with the
internal cutaneous (n. cutaneus brachii posterior) branch of the mus-
culo-spiral nerve (n. radialis).
Last Thoracic, — is larger than the other thoracic nerves. Its anterior
division runs along the lower border of the last rib, and communicates
with the first lumbar nerve by the thoraco-lumbar branch, also with
the ilio-hypogastric branch of the lumbar plexus. One of its
branches, the —
Lateral Cutaneous- of the i2th Thoracic, — is also of large size, and is dis-
tributed to the integument over the front part of the gluteal region,
some of its filaments extending as low as the trochanter major of the
femur.
232 HUMAN ANATOMY
THE LUMBAR NERVES
The Lumbar Nerves are 5 in number on each side. Their roots are large
and descend vertically in the spinal canal to reach their respective inter-
vertebral foramina of exit. Their posterior divisions pass backward
between the transverse processes, and divide into internal (medial)
branches, supplying the deep muscles of the back; and external (lateral)
branches are mostly cutaneous. Their anterior divisions pass outwardly
behind the psoas magnus muscle or between its fasciculi. The anterior
divisions of the upper 4 nerves are connected by anastomotic loops, form-
ing the lumbar plexus; that of the 5th with a branch of the 4th forms the
lumbo-sacral cord (truncus lumbosacralis), which joins with the anterior
divisions of the upper 3 sacral nerves and part of the 4th to form the sacral
plexus. (See Plate 14.)
The Lumbar Plexus (plexus lumbalis) (Plate 14), is formed by loops
from the 1 2th thoracic and the upper 4 lumbar nerves. It is situated in the
substance of the psoas magnus muscle in front of the transverse processes
of the lumbar vertebrae. Its branches are given off by the connecting
loops, and are as follows: —
Ilio-hypo gastric, — from the ist lumbar nerve, to the integument of the
gluteal and hypogastric regions.
Ilio-inguinal, — from the ist lumbar nerve, gives off muscular branches
to the internal oblique as it pierces it. It then accompanies the
spermatic cord, or round ligament, divides into anterior scrotal or
anterior labial to the integument of the upper and inner thigh and to
the scrotum or labium majus.
Genito-crural (genito-f emoral) , — from the ist and 26. lumbar nerves,
gives off genital branch (n. spermaticus externus), to the cremaster
muscle or round ligament, and a femoral branch (n. lumbo-inguinalis)
to the integument over the anterior superior part of the thigh.
External Cutaneous (n. cutaneus femoris lateralis), — from the 2nd and
3rd lumbar nerves, to the integument of the anterior, outer and pos-
terior parts of the thigh.
Obturator (n. obturatorius), — from the 2nd, 3rd, and 4th lumbar nerves,
through the obturator foramen, to the obturator externus and adduc-
tor muscles of the thigh, the hip- and knee-joints, and occasionally the
integument of the thigh and leg.
Accessory Obturator (n. obturatorius accessorius) (often absent), — from
the 3rd and 4th lumbar nerves, to the pectineus muscle and the
hip-joint.
THE SPINAL NERVES 233
Anterior Crural (n. femoralis), — from the 2nd, 3rd, and 4th lumbar
nerves, to the iliacus and pectineus muscles, all the muscles on the
front of the thigh except the tensor fasciae femoris, the hip- and knee-
joints, and the integument on the front and inner side of the thigh. It
descends through the psoas magnus muscle, passing beneath Pou-
part's inguinal ligament to the thigh, where it divides into an interior
and a posterior division. Its branches are —
Muscular, within the abdomen, to the iliacus muscle.
Arterial, within the abdomen, to the femoral artery.
Middle Cutaneous, to the skin on the front of the thigh.
Internal Cutaneous, to the skin on the knee and leg.
Muscular, to the pectineus and sartorius muscles.
Long Saphenous (n. saphenus), to the skin over the patella and that on
the front and inner side of the leg.
Muscular, to the quadriceps extensor muscle.
Articular Branches, to the hip- and knee-joints.
THE SACRAL AND COCCYGEAL NERVES
The Sacral Nerves number 5, the Coccygeal i, on each side. Their roots
are long and descend vertically in the spinal canal as the cauda equina or
horse's tail, to reach their respective foramina of exit. Their posterior divi-
sions are small; they supply the multifidus spinae muscles and the skin of
the gluteal region; those of the lower 2 sacral and the coccygeal supplying
the extensor coccygis and the skin over the coccyx. Their anterior divisions
communicate with the sacral ganglia of the sympathetic; those of the 3
upper sacral, with the lumbo-sacral cord (truncus lumbo-sacralis) and a
branch from the 4th sacral, unite to form the sacral plexus. The anterior
division of the 4th sacral divides into visceral and muscular branches, the
former supplying the pelvic viscera, the latter the levator ani, sphincter
ani, and coccygeus muscles. The anterior division of the 5th sacral and
the coccygeal supply the coccygeus muscle and the skin over the coccyx.
The Sacral Plexus (Plexus Sacralis) (Plate 14), — is formed by the union
of the anterior divisions of the upper 3 and part of the 4th sacral nerves (c),
with the lumbo-sacral cord (truncus lumbo-sacralis) (a) derived from the
4th and 5th lumbar nerves. The plexus lies upon the pyriformis muscle, is
covered by the pelvic fascia, communicates with the sympathetic, and
gives off 2 great nerve-trunks or cords, the upper cord being prolonged as the
great sciatic nerve, the lower cord becoming the pudic nerve, both passing
out of the pelvis by the great sacro-sciatic foramen. The branches of the
sacral plexus are as follows: —
234
HUMAN ANA10MY
FIG. 80.
Muscular Branches, — to the pyriformis, obturator interims, the 2 gemelli
and the quadratus femoris.
Superior Gluleal (n. glutaeus superior) (b), — from the lumbo-sacral cord,
to the gluteus medius and minimus muscles
and the tensor fasciae femoris.
Inferior Gluleal (n. glutaeus inferior), — from the
lumbo-sacral cord and the ist and 26. sacral
nerves, to the gluteus (glutaeus) maximus muscle.
Small Sciatic (n. cutaneus femoris posterior) (/), —
from the 2d and 3d sacral nerves, to the integu-
ment of the perineum and back part of the thigh
and leg, by gluteal, perineal and femoral cuta-
neous branches.
Perforating Cutaneous (n. clunium inferior medialis),
sometimes classed as a branch of the "pudendal
plexus," — from the 2d and 3d sacral nerves,
perforating the great sacro-sciatic (sacro-tu-
berous) ligament, to the skin over the gluteus
maximus muscle.
Pudic (n. pudendus), sometimes classed as a branch
of the "pudendal plexus" (e),— from the 3d and
4th sacral nerves, escapes by the great sacro-
sciatic foramen, crosses the spine of theischium,
and re-enters the pelvis through the lesser sacro-
sciatic foramen, to supply the perineum, anus
and genitalia. Its branches are the —
Inf. Hemorrhoidal (n. haemorrhoidalis inferior).
Perineal (n. perinei), dividing into 2 super-
ficial perineal cutaneous branches and mus-
cular branches to all of the perineal muscles.
Dorsal Nerve of the Penis (n. dorsalis penis vel
clitoridis).
Great Sciatic (n. ischiadicus) (g), — the largest ner-
vous cord in the body, and the continuation of
the upper cord of the sacral plexus, arises from
the lumbo-sacral cord and the upper 4 sacral
nerves, and escapes by the great sacro-sciatic
foramen to the back of the thigh, giving off —
Articular Branches (rami articulares), to the hip-joint.
Muscular Branches (rami musculares), to the flexor muscles of the
THE SPINAL NERVES 235
leg, viz. — the biceps, semitendinosus and semimembranosus, also
to the adductor magnus.
External (n. peronaeus communis) (K) and Internal (n. tibialis) (i)
Popliteal, the terminal branches, generally arising at the lower
third of the thigh.
The Internal Popliteal Nerve (n. tibialis) (i), the larger of the two ter-
minal branches of the great sciatic, descends along the back of the lower
thigh and the middle of the popliteal space, to the lower part of the
popliteus muscle, where it becomes the Posterior Tibial Nerve (&). Its
branches are the —
Articular (rami articulares) 3, — supplying the knee-joint.
Muscular (rami musculares) (j), 4 or 5, — to the gastrocnemius, plantaris,
soleus and popliteal muscles.
Communicant Tibialis (ramus anastomoticus tibialis), — joins the com-
municans peronei from the external popliteal nerve to form the —
External or Short Saphenous (n. cutaneus surae medialis) (/»), — descends
to the outer malleolus and is distributed to the skin of the outer side of
the foot and the little toe.
The Posterior Tibial Nerve (&), the continuation of the internal popliteal
descends along the back of the leg to behind the inner malleolus, where it
divides into the External (lateral) and Internal (medial) Plantar nerves (/).
Its branches are the —
Muscular (rami musculares), — to the soleus, tibialis posticus, flexor
longus digitorum and flexor longus hallucis.
Calcaneo- plantar or Internal Calcaneal (rami calcanei mediales), — to the
skin of the heel and inner side of the sole of the foot.
Articular (ramus articularis ad articulationem talocrualem), — to the
ankle-joint.
Internal Plantar (n. plantaris medialis), — to the inner plantar muscles,
sole of the foot, and the plantar integument of the inner 3^ toes (nn.
digi tales plantares communes).
External Plantar (n. plantaris lateralis), — to the external plantar mus-
cles, and the plantar integument of the outer ij^j toes (nn. digitales
plantares communes).
The External Popliteal or Peroneal Nerve (n. peronaeus communis) (h),
the smaller of the two terminal branches of the great sciatic (n. ischiadicus),
descends from the bifurcation of the latter nerve, obliquely along the outer
side of the popliteal space, winds around the neck of the fibula, and about
an inch below the head of that bone it divides into the Anterior Tibial
or Deep Peroneal (n. peronaeus profundus) (m) and Musculo-cutaneous or
236 HUMAN ANATOMY
Superficial Peroneal (n. peronaeus superficialis) (n) nerves. Its branches
are —
Articular (rami articulares), 3, — to the front and outer side of the knee.
Cutaneous (n. cutaneus surae lateralis), 2 or 3, — to the integument along
the back and outer side of the leg. One of these branches, the —
Communicant Peronei (ramus anastomoticus peronaeus), — joins with the
communicans tibialis (ramus anastomoticus tibialis) (see above)
to form the external saphenous nerve (n. cutaneus surae medialis).
Anterior Tibial or Deep Peroneal (n. peronaeus profundus) (m), — sup-
plying the extensor muscles, the ankle-joint, and the integument of
the adjacent sides of the great and 26. toes.
Musculo-cutaneous or Superficial Peroneal (n. peronaeus superficialis)
(n), — by 2 branches (0) (internal and external) to the peroneal
muscles, the integument of the ankles, and the dorsal integument
(n. cutaneous dorsalis medialis) and sides of all the toes, except the
outer side of the little toe and the adjoining sides of the great and 2d
toes, the former being supplied by the external saphenous (n. cuta-
neus surae medialis), and the latter by the internal (medial) branch of
the anterior tibial.
THE SYMPATHETIC SYSTEM
The Sympathetic Nervous System consists of — a series of ganglia,
connected together by intervening cords, one series on each side of the
median line of the body, partly in front and partly on each side of the
vertebral column, beginning in the ganglion of Ribes on the anterior com-
municating artery and ending in the ganglion impar in front of the coccyx;
three great gangliated plexuses, situated in the thoracic, abdominal, and
pelvic cavities respectively; smaller ganglia, in relation with the abdominal
viscera; and numerous communicating and distributing nerve fibres.
(See Plate 16.)
Ganglia in the Cranium. Besides the ganglia of the cranial nerves
(described on page 223), all of which are connected with the sympathetic,
there are in the cranium or in its immediate vicinity certain ganglia belong-
ing to the sympathetic system, as follows: —
Carotid Ganglion, — on the internal carotid artery.
Ganglion of Bochdalek, — above the canine tooth at the junction of a
branch from the spheno-palatine ganglion with the middle superior
alveolar and anterior superior alveolar nerves.
Ganglion of Valent ine, —situated at the juncture of the middle superior
alveolar and the posterior superior alveolar nerves.
THE SYMPATHETIC SYSTEM 237
The Carotid Plexus is situated on the outer side of the internal carotid
artery, as it lies by the side of the body of the sphenoid bone, and is formed
by filaments from the outer branch of the superior cervical ganglion. It
communicates with the Gasserian ganglion (ganglion semilunare) and the
6th nerve; also with the tympanic branch of the gth by two branches, the
small deep petrosal and the carotko-tympanic; and with the spheno-pala-
tine ganglion by the large deep petrosal, which joins the great superficial
petrosal to form the Vidian nerve (n. canalis pterygoidei) before entering
the ganglion (see page 226).
The Cavernous Plexus is situated in the upper portion of the cavernous
sinus, below the last bend of the internal carotid artery, and is formed
chiefly by the internal division of the ascending branch from the superior
cervical ganglion. It communicates with the 3rd, 4th, ophthalmic divi-
sion of the $th, and the 6th nerves, also with the ophthalmic ganglion. It
sends filaments to the wall of the internal carotid artery, which are pro-
longed into plexuses around the cerebral and ophthalmic arteries. The
filaments on the anterior communicating artery form the ganglion of Ribes,
which here connects the sympathetic of the two sides of the body.
«tf THE GANGLIATED CORD (TRUNCUS SYMPATHETICUS)
" '
The Cervical Ganglia are 3 in number on each side of the neck, the supe-
rior, middle and inferior cervical; of which the superior is the largest and is
probably formed by the coalescence of four ganglia corresponding to the
upper four cervical nerves. They are as follows: —
Superior Cervical Ganglion, — of fusiform shape, situated behind the
carotid sheath opposite the transverse processes of the 2d and 3d
cervical vertebrae. Its branches form the carotid, cavernous, and
pharyngeal plexuses; one of its internal branches unites with the
superior laryngeal nerve, and another is the superior cervical cardiac
nerve going to the cardiac plexuses.
Middle Cervical Ganglion, — on the inferior thyroid artery, opposite the
6th cervical vertebra gives off the middle cardiac nerve to the deep
cardiac plexus, also many communicating branches.
Inferior Cervical Ganglion, — on the superior intercostal artery, between
the neck of the ist rib and the transverse process of the 7th cervical
vertebra. It gives off several communicating branches and the
inferior cardiac nerve to the deep cardiac plexus.
The Thoracic Ganglia are 1 1 or 1 2 in number on each side of the spine,
resting against the heads of the ribs and covered by the pleura costalis,
238 HUMAN ANATOMY
except the last two, which are placed on the side of the bodies of the nth
and 1 2th thoracic vertebrae. Occasionally two ganglia coalesce into one,
and the first is frequently blended with the last cervical ganglion. They
are connected together by cords prolonged from their substance. They
receive branches (white rami communicantes) from the thoracic nerves.
They give off central branches (gray rami communicantes) connecting with
the thoracic spinal nerves; and peripheral branches from the upper 5 or 6
ganglia to the thoracic aorta, etc., from the 3rd and 4th ganglia to the
posterior pulmonary plexus, and from the lower 6 or 7 ganglia to form by
their union the three splanchnic nerves, as follows: —
Great Splanchnic, — from branches of the 5th to the loth inclusive, con-
necting with the upper 5, passes through the posterior mediastinum,
perforates the crus of the diaphragm, to the semilunar (coeliac)
ganglion of the solar (cceliac) plexus.
Lesser Splanchnic, — from the loth and nth, passes through the dia-
phragm with the great splanchnic, to the renal and solar (cceliac)
plexuses.
Least or Renal Splanchnic, — from the last thoracic ganglion, also per-
forates the diaphragm, and ends in the renal plexus; it is not always
present.
The Lumbar Ganglia consist usually of 4 small ganglia on each side,
connected together by intervening cords, and situated in front of the ver-
tebral column. Their central branches (gray rami communicantes) com-
municate with the lumbar spinal nerves. Of their peripheral branches
some help to form the aortic plexus, others go to the hypogastric plexus,
and all give off numerous filaments to the bodies of the lumbar vertebrae
and the ligaments connecting them. The lumbar ganglia receive branches
(white rami communicantes) from the ist, 2d and sometimes 3d lumbar
nerves.
The Pelvic Ganglia are 4 or 5 small ganglia on each side, connected to-
gether by intervening cords, and situated in front of the sacrum. The
lower cords of each side converge below and unite on the front of the coccyx
in the coccygeal ganglion or ganglion coccygeum impar. Their central
branches (gray rami communicantes), 2 from each ganglion, communicate
with the sacral nerves. Of the peripheral branches, some pass to the pelvic
plexus, others go to a plexus on the middle sacral artery and all communi-
cate on the front of the sacrum with the corresponding branches of the
other side. The sacral portion of the sympathetic trunk receives one with
rami communicantes.
THE SYMPATHETIC SYSTEM 239
THE GREAT PLEXUSES (Plate 16)
The Great Plexuses of the Sympathetic are large aggregations of nerves
and ganglia, situated in the tkpracic, abdominal, and pelvic cavities, and
named the Cardiac Plexus, the Coeliac or Solar Plexus, and the Hypo-
gastric Plexus. Their branches form secondary plexuses which supply the
viscera of the cavities, as described below.
The Cardiac Plexus is situated at the Jjase of the heart, and is divided
into a superficial portion and a deep portion, both of which are closely con-
nected with each other. They form by their branches the anterior and
posterior coronary plexuses and the anterior pulmonary plexus.
The Superficial Cardiac Plexus is formed by the left superior cardiac
nerve, the left inferior cervical cardiac branches of the pneumogastric, and
filaments from the deep cardiac plexus. At the junction of these nerves a
small ganglion, the cardiac ganglion of Wrisberg, is occasionally found, situ-
ated immediately beneath the arch of the aorta on the right side of the
ductus arteriosus (ligamentum arteriosum). This plexus lies in the con-
cavity of the arch of the aorta, and in front of the right pulmonary artery.
Branches from it pass to the —
i Right Anterior Coronary Plexus, — formed chiefly from the preceding,
also from the deep cardiac plexus. It passes forward between the
aorta and the pulmonary artery. It follows the ramifications of the
right coronary artery on the anterior surface of the heart.
Right and Left Anterior Pulmonary Plexuses, — are formed by filaments
from the superficial and deep cardiac plexuses and the anterior pul-
monary branches of the vagus nerve. Branches from them accompany
the ramifications of the bronchial tubes throughout the lungs. The
Right and Left Posterior Pulmonary Plexuses are formed by the pos-
terior pulmonary branches of the vagus and branches from the 3rd
and 4th thoracic ganglia of the sympathetic. They are not con-
nected with the cardiac plexuses. They are situated on the pos-
terior aspect of the roots of the lungs, and their branches accompany
the ramifications of the bronchial tubes.
The Deep Cardiac Plexus is formed by the cardiac nerves derived
from the cervical ganglia of the sympathetic and the cardiac branches of
the recurrent laryngeal and pneumogastric nerves. The only cardiac
nerves which do not enter into its formation are those forming the super-
Seta! cardiac plexus, namely — the left superior cardiac and the inferior
. cervical cardiac branches of the vagus. This plexus lies in front of the
bifurcation of the trachea and behind the arch of the aorta. Its branches
240 HUMAN ANATOMY
on the right side pass in front and behind the right pulmonary artery
to the anterior pulmonary plexuses, the anterior (right) and posterior
(left) coronary plexuses, and the right auricle; those on the left side give
filaments to the superficial cardiac and anterior pulmonary plexuses and
the left auricle, and then form the greater part of the —
Left or Posterior Coronary Plexus, — is formed by filaments from both
sides of the deep cardiac plexus. It surrounds the branches of the
left coronary artery at the back of the heart, and its filaments are
distributed with those vessels to the muscular substance of the
ventricles.
Ganglia, — are found on the cardiac nerves, both on the surface of the
heart and in its muscular substance.
' The Epigastric (Cceliac) or Solar Plexus, sometimes called the abdomi nal
brain, consists of a great network of nerves and ganglia, situated behind
the stomach and in. front of the aorta and the crura of the diaphragm,
surrounding the cceliac axis and the root of the superior mesenteric artery.
Its principal ganglia are the two Semilunar (coeliac) Ganglia, irregular
gangliform masses, formed by the aggregation of smaller ganglia with
interspaces between them, situated one on each side of the plexus, and
in front of the crura of the diaphragm, close to the supra-renal capsules.
This plexus and its connected ganglia receive the great and small splanch-
jiic nerves of both sides, and some filaments from the right pneumogastric.
It distributes filaments over all the branches from the front of the
abdominal aorta, forming the following plexuses: —
/ Phrenic or Diaphragmatic Plexus, — arises from the upper part of the
semilunar ganglion, and receives one or two branches from the phrenic
nerve. It accompanies the phrenic artery and supplies the dia-
phragm, some filaments going to the supra-renal capsule. At its
junction with the phrenic nerve on the right side is the —
Ganglion Diaphragmaticum, — a small ganglion at the juncture with
the right phrenic nerve, it is situated on the under surface of the
diaphragm, near the right supra-renal capsule.
. Supra-renal Plexus, — is formed by branches from the solar plexus, the
semilunar ganglion, the phrenic and great splanchnic nerves. Its
branches are large, and supply the supra-renal capsule.
Renal Plexus, — is formed by filaments from the solar plexus, the serai-
lunar ganglion, the aortic plexus, and the lesser and smallest splanch-
nic nerves, some 15 or 20 in all, which have numerous ganglia
on them. They accompany the branches of the renal artery into the
kidney, some filaments going to the inferior vena cava and to the
spermatic plexus.
THE SYMPATHETIC SYSTEM 241
Spermatic Plexus— is derived from the renal plexus and receives fila-
ments from the aortic plexus. It accompanies the spermatic vessels
to the testes. In the female it is called the Ovarian Plexus, and is
distributed to the ovaries and the fundus of the uterus.
Superior Gastric or Coronary Plexus, — joins with branches from the
left pneumogastric nerve, and accompanies the gastric left artery along
the lesser curvature of the stomach, being distributed to that viscus.
Hepatic Plexus, — receives filaments from the left pneumogastric and
the right phrenic nerves, accompanies the hepatic artery, and ramifies
in the substance of the liver upon the branches of that artery and those
of the portal vein. It gives off branches to all the divisions of the
hepatic artery, forming pyloric, gastro-duodenal, gastro-epiploic
(inferior gastric), and cystic plexuses, on the arteries similarly named.
/Splenic or Lienal Plexus, — is formed by branches from the cceliac plexus,
the left semilunar ganglion, and the right pneumogastric nerve.
It accompanies the splenic artery and its branches to the substance
of the spleen, and gives off filaments to the pancreas and the left
gastro-epiploic plexus.
Superior Mesenteric Plexus, — is a continuation of the solar plexus, and
receives a branch from the right pneumogastric nerve. It surrounds
the superior mesenteric artery, and divides into pancreatic, intes-
tinal, ileo-colic, right colic, and middle colic branches, which are
distributed to all the parts supplied by that artery. Its nerves have
numerous ganglia upon them near their origin.
Aortic Plexus, — on the sides and front of the aorta, between the origins
of the superior and inferior mesenteric arteries; is formed by branches
from the solar (cceliac) plexus and semilunar (cceliac) ganglia, and
receives filaments from the lumbar ganglia. It sends branches to
the spermatic, inferior mesenteric, and hypogastric plexuses, also
some filaments to the inferior vena cava. A part of it is the —
Inferior Mesenteric Plexus, — divides into left colic, sigmoid, and superior
haemorrhoidal plexuses, and supplies the descending colon and the
rectum.
The Hypogastric Plexus is formed by filaments from the aortic plexus
and the lumbar ganglia, and is situated in front of the promontory of the
sacrum between the two common iliac arteries. It contains no evident
ganglia, and bifurcates into two lateral divisions, the Pelvic or Inferior
Hypogastric Plexuses, one on ea,ch side of the rectum, which receive branches
from the 2nd, 3rd, and 4th sacral nerves, and the first two sacral ganglia.
They give off numerous branches along the branches of the internal iliac
16
242 HUMAN ANATOMY
arteries to the pelvic viscera, forming the following secondary plexuses,
viz. —
Inferior Hamorrhoidal Plexus, — to the rectum.
Vesical Plexus, — to the bladder, vesiculae seminales, and vas deferens.
Prostatic Plexus, — to that gland and the vesiculae seminales, also to the
erectile tissue of the penis as the large and small cavernous nerves.
Vaginal Plexus, — to the vagina, gives off anteriorly the cavernous plexus
of the clitoris from which arise the greater and lesser cavernous
nerves of the clitoris.
Uterine Plexus, — to the uterus and Fallopian tube.
TABLES AND PLATES
OF THE
NERVOUS SYSTEM
NOTE. — The folio-wing Tables are of original arrangement, and are designed to
show the origin, formation and distribution of each nerve. They are self-explana-
tory with the aid of the accompanying Plates.
244
HUMAN ANATOMY
THE CRANIAL NERVES
I Ethmoidal foramina, 20,
ist NERVE, — Olfactory. Function, — smell. Exit, — •< in cribriform plate of
(See page 216) [ Ethmoid bone.
Ext. Root, Posterior division of the Rhin- |
encephalon or "Limbic lobe." istN.
Mid. Root, Optic thalamus. [ and
Int. Root, Posterior division of the Rhin- | Bulb.
encephalon or "Limbic lobe."
Ext. Filaments, to Schneiderian
membrane over sup. turbin-
al and ethmoid bones.
Int. Filaments, to Septum
(upper third).
Exit, — Optic foramen.
2nd NERVE, — Optic. Function, — sight.
(See page 217)
This table is too long for the width of the page, and breaks at the Optic Commissure,
which is repeated again where the table continues below.
Optic thalamus
Ext. geniculate
Corp. quad. ant.
Corp. quad. ant. |
Optic thalamus J
| Longitudinal
Fibres -j Decussating
[ Commissural
\ Commissural
Left Optic Tract
( Longitudinal J
OPTIC
COMMISSURE
or CHIASM.
OPTIC
COMMISSURE
or CHIASM.
[ Longitudinal, to temporal li of retina
Optic N. \ Decussating, fr. opp. tract to nasal Yt of ret. \ L. Eye.
[ Inter-retinal, fr. opp. retina to retina.
2d
f Inter-retinal, fr. opp. retina to retina.
Optic N. \ Decussating, fr. opp. tract to nasal te of ret. }• R. Eye.
[ Longitudinal, to temporal J-i of retina.
3d NERVE,— Motor Oculi.
(See page 217)
Nucleus in 1
floor of the 1 . „.
Aqued.ofSyl. j 3
Crus cerebri. J
Function, — motion. Exit, — Sphenoidal fissure.
fSup. Branch, to Lev. palp, sup., Rectus superior.
. / to Rectus int., Rect. Inf., Inf. oblique.
Inf. Branch s L ' ... '
( motor root to Ciliary Ganglion.
Supplies all the muscles of the orbit (except the superior oblique and ext. rectus) , also
the sphincter of the iris and the ciliary muscle through the ciliary ganglion.
Function, — motion.
Exit, — Sphenoidal fissure.
4th NERVE,— Trochlear.
(See page 217)
f to Sup. Oblique on upper (orbital) surface.
4th N. \ Branch to Cavernous Plexus of Sympathetic.
I Recurrent Branch, to lateral sinus.
Aq. of Sylvius.
Crus cerebri.
Is the smallest cranial nerve, with the longest nerve-course in the cranial cavity.
THE CRANIAL NERVES
Plate 6
longitudinal Fibres
Decussating Fibres
Conuni&sura/Fibres _.
fnter-reiinul Fibr&r
PoKerdeL
245
246
HUMAN ANATOMY
$th NERVE, — Trigeminus.
(See page 218.)
Functions, Sensation, Motion.
(i) OPHTHALMIC
by Sphenoidal
fissure.
Frontal <
Lacrimal, to
Supraorbital.
Supratrochlear.
gland, etc.
Ganglionic.
Long Ciliary.
Nasal.
Infratrochlear.
Int. Nasal.
Ext. Nasal.
Meningeal.
Origin.
Nucleus and
/-> i'A t / Temporal.
Orbital, < ,,
[ Malar.
Locus Cae-
Spheno-palatine.
rul. in the
(2) MAXILLARY
Post. Sup. Denial.
medulla
oblongata
by For. rotund.
Mid Sup. Denial. \ .
Ant. Sup. Denial. / 'n canal-
for the
Palpebral, }
Sensory Root.
Nuclei in floor
of 4th Ven-
5th N.
Trigeminus
or Trifacial.
Nasal, > on the face.
Labial, J
Recurrent.
tricle, and
( Ant. Br. *
Aq. of Syl-
Int.Pterygoid, j pQgt B^.
vius, for the
Masseteric. *
Motor Root or
( Ant. Br. *
Masticator
Deep Temporal j pos^ ]}r>«
Nerve.
Buccal.
Ext. Plerygoid.*
Br. to facial n.
(3) MANDIBU-
LAR. (including
masticator) by
For. Ovale.
A uriculo-
Temporal.
Br. to otic g.
Ant. Auricular.
to Meat. Aud.
to articulation.
Parotid.
Sup. Temporal.
Lingual
Br. of Comm'n.
Br. of Distrib'n.
Mylo-hyoid. *
Inferior
Dental Brs.
Dental.
Incisive. \ . . .
A , > terminal
Mental. J
Motor Branches (Masticator Nerve), going to the muscles of mastication.
T r XT Plate7
THE CRANIAL NERVES.
5l.h Nerve,-Trigeminus.
iotter.del
247
248
HUMAN ANATOMY
7th NERVE, — Facial, or Portio Dura.
(See page 220.)
Function, — Motion, Special Sense (taste)
In auditory '
canal.
> Br. to Auditory nerve.
Large Superf. Petrosal, to Meckel's
ganglion.
.
Small Superf. Petrosal, to otic
.0
In Aqueduct
ganglion.
1
of Fallopius.
Ext. Superf. Petrosal, to menin-
'%
geal plex.
a
§
Br. to Auricular of pneumogas-
g
tric.
o
O
Origin.
Nucleus in
floor of the
•8
1
At exit from
the Stylo-
Br. to Great Auricular (cerv.
plex.).
Br. to Auriculo-Temporal (sth).
4th Ventricle,
and groove
o
a
rt
Foramen.
Br. to Pneumogastric.
Br. to Glosso-pharyngeal.
between
Olivary and
7th N.
Facial
W
Behind the
ear.
> Br. to small Occipital.
Restiform
facial
On the face.
Brs. to 3 divisions of the sth nerve.
bodies of
medulla
In the neck.
Br. to Superficial Cervical.
oblongata.
Solitary
Tympanic Nerve, to Stapedius
Tract.
In Aqueduct ^
muscle.
e
of Fallopius.
Chorda Tympani Nerve (glosso-
|
palatine) , to the tongue and palate.
s .
"o
Near Stylo- 1
mastoid <
Foramen.
'/ Auricular.
Post. A uncular < _ . . .
\ Occipital.
Br. to Digastric muscle.
Br. to Stylo-hyoid muscle.
C/3
0)
•S
( Temporal.
d
2
f
Temporo-facial •< Malar.
pq
1
{ Infra-orbital.
On the face. * \
(Buccal.
I
Mandibular.
r
Cervical.
* Forming the Pes A nserinus, or Goose's-foot, as these branches are named.
THE CRANIAL NERVES.
71'1 Nerve -Facial, or Portia Dura.
PlateS
References
1 LargeSuperf. Petrosal.toform V«Jlan wit
2 Small Supe^ PetrosaUo Optic Ganghor
3 External Superf. Fetrosal, to Plaus on M
4 Tympanic Br to Stapedius.etc.
3 Br n-om Carotid Plexus.Making Vidia^with NOf
). 7. Eirs to Aur.culo -Temporal £ 5
V Br to Auricular of
24Q
250
HUMAN ANATOMY
9th NERVE, — Glossopharyngeal. Functions, — Sensation, Special Sense.
(See page 221.)
Communica- j
Large Petrosal.
Small Petrosal.
ting Brs. to 1
Carotid Plexus.
Clrioiti ^
1 ympantc or
LJrigin.
Tractus soli-
tarius and floor
pth Nerve
Glosso-
Jacobson's N.
Distributing I
Fenestra vestibuli.
Fenestra cochlea?.
of 4th vent.
pharyn-
Brs. to
Eustachian tube.
and the
geal, by
Carotid Branches,— along Int. Carotid artery.
medulla oblong.
Jugular
Pharyngeal Br. — to Pharyngeal Plexus.
behind the
Foramen.
Muscular Br. — to Stylo-pharyngeus.
olivary body.
Tonsillar Brs.— to Tonsillar Plexus.
Lingual Brs. — to base and posterior ^ of tongue;
nerve of taste.
loth NERVE, — Pneumogastric, or Vagus. Function, — Motion, Sensation.
(See page 221.)
Meningeal, to dura mater.
Auricular (Arnold's Nerve), to external ear.
Pharyngeal, to that plexus.
Origin.
Funic. soli-
Sup. Laryngeal < T Xt'T aryng'
( Int. Laryng.
crico-thyroid).
supplies all the
tarius, nucleus
laryngeal
ambiguus, floor
loth Nerve
Recurrent Larynpf-f-l •
muscles except
of 4th ventricle
Vagus, by
Cervical Car-
crico-thyroid and
and the medulla
Jugular
diac.
to cardiac
arytenoideus.
oblongata be-
Foramen.
Thoracic Car-
plexus.
tween olivary
diac.
and restiforn
bodies.
Ant. Pulmonary. \
-. „ , /-to pulmonary plexus.
Post. Pulmonary. }
(Esophageal, to that plexus.
Gastric Brs., to the stomach.
Hepatic, to the hepatic plexus.
terminal brs.
Gives sensation to external ear and larynx, motion to other parts, also vaso-
motor, inhibitory, trophic and secretory influences. A nerve of deglutition, phona-
tion, respiration, circulation, and digestion. The Auriculo-Laryngo-Pharyngo-
CEsophago-Tracheo-Pulmono-Cardio-Gastro-Hepatic Nerve.
nth NERVE, — Spinal Accessory (N. ACCESSORIUS).
(See page 222.)
Function, — Motion.
Origin.
Floor of 4th
ventricle, and
gray horn of
cord, down to
6th Cervical N.
nth Nerve,
by Jugu-
lar Fora-
men.
Branches, to Pharyngeal and Sup. Laryngeal of
Vagus.
Internal, anastomosing with Vagus, is probably
the Recurrent Laryngeal Br. of the latter nerve.
/ Sterno-mastoid.
External, or Muscular, tos _
^ Trapezius.
A motor nerve to the muscles named, and probably to the larynx also.
Plate 9
a, THE CRANIAL NERVES.
9'.* or Glosso- pharyngeal,
I0l.h or Pneumo gastric,
II fc.h or Spinal Accessory.
References.
IJugular Ganglion of 3th Nerve
Z.Petroui Ganglion of 9th Nerve
3.Ganglion of the Vagu5 Rook.
4. Ganglion of the Vagus Trunk.
5. Medullary part OF IP* Nerve.
6.Spinal part of ||f." Nerve.
7 Sup Cardiac Br JOINING Cardiac of 5ympafhetic
8.5ubclavian Artery on right side, Arch of the
Aorla on left side of the body.
9.Foramcn Magnum, receiving 5pinaf part of
the Spinal Accessory.
10. Jugular Foramen.transmitl'ng all three Nerves
II Branches to the Hypooloisal Sympathetic
cervical fierves '
12. Olivary body, (in broken line).
Potter.del.
251
252
HUMAN ANATOMY
6th NERVE, — Abducens (see page 219).
Origin. — A nucleus
in floor of 4th ven-
tricle, and the ^6th Nerve, Abducens.
pyramid of the
medulla oblongata.
Function, — Motion.
Exit by sphenoidal fissure to the
Ext. Rectus muscle of the eyeball.
Branch, to the sympathetic.
8th NERVE, — Auditory, OR ACUSTIC.
Function, — Special Sense.
Origin. — Striae in
floor of the 4th
ventricle, and
groove between
the pons and
medulla.
8th Nerve,
Auditory.
f 2 Semi-circ. canals.
Vestibular, toj Utricle.
[ Saccule.
J Post. Semi-circ. canal.
Cochlear, to \ Saccule and Utricle.
1 Cochlea, and Organ of Corti.
A nerve of special sense (hearing), described on page 220, ante. It goes by the
Internal Auditory Meatus, through the Internal Auditory Canal, to the internal ear.
It is the only cranial nerve which does not leave the cranial wall.
i2th NERVE, — Hypoglossal (NONUS OR QTH OF WILLIS).
(See page 222.) Function, — Motor of tongue, etc.
Brs. to
Origin. — Floor of
4th ventricle, and
groove between
the pyramid and
olivary body of
medulla. J
1 2th Nerve,
Hypoglossal.
Descendens
Hypoglossi.
/ Lingual of 5th.
Communicating I Symphatic.
I i, 2 Cervical.
( Vagus.
IBr. to Sterno-hyoid.
Br. to Sterno-thyroid.
Br. to Omo-hyoid.
Joins Communicans Hypo-
glossi.
Thyro-hyoid, to that muscle.
Muscular, to
j Stylo-glossus.
I Hyo-glossus.
I Genio-hyoid.
[ Genio-hyo-glossus.
Exit, by Ant. Condylar foramen (Canalis hypoglossi).
THE CRANIAL NERVES.
6th Nerve,- Abducens.
to RectErter
Plate 10
riaal .Nerve^ of^
J& ^
1 2** Nerve, -
Hypoglossal
(Nonus or 9^ of Willis)
.5**'
Infra.
. 3upnz-, ,
4 Aunculo-temporal.SW
5 Lachry
7.
.,
9. Ibstertor Auricular??*
V
Rjtter del
253
and 0mo-
254
HUMAN ANATOMY
THE SPINAL NERVES
8 CERVICAL, 12 THORACIC, 5 LUMBAR, 5 SACRAL, i COCCYGEAL
N. B. — Read from the Black Type outwards to left and right
Brs
3, to Recticap. Muscles.
Post Div. of 2d N.
2 Cerv. N.
Post M. of head, etc. POST. ] ist Cerv
cal | ANT. Commun'g Vagus N.
Complexus Muscle. Div. \ Nerve.
j Div. Brs. to | Hypogl. N.
Skin of occiput.
J Sub-occij
pital (
Sup. Cerv.
Gang.
Br.
to Occip-atloid artic'n.
Splenius
Cerv. ascendens
Transv.-colli
Ext. Branch
Br. to Spinal accessory
Trach-mastoid
supplying
Fil.to Sterno-mastoidM.
Complexus
POST.
. ANT.
Cervical
Asc. Br. to ist Cerv. N.
Desc. Br. to 3d Cerv. N.
to ist Cerv. N.
)lnt. Br. or
Nerve.
Fil. to Commun. Hyp.
Skin of occiput.
Great Occip.
Occipitalis Minor N.
Auricular.
Auric. Magnus N.
Splenius
A seen
Superf. Cervical N.
Cerv. ascend.
Ext. Br.
Br.
Br. to 2d Cerv. N.
Trans, colli
supplies
Br. to Spinal-ac.
Trach-mast.
POST. 1 . 3d
n.,, Cervic
, ANT. •
al I Div.
Fil. to 4th Nerve.
] Int. Br. ""' 1 Nerv
Integument 1
of occiput. J
J supply
e. J Descen. Fil. to Lev. ang. scap.
Br. Supra-clavicular.
Fil. to Com. Hypogl.
Fil. to Phrenic N.
Fil. to 3d Cerv. N.
. / POST. \ 4th Cervi
Muscles of the Back, f ^_ > XT
-al f ANT FU" tO 5th CerV' N>
D.v 1 FiL to Phrenic N"
^ i-»iv. j nerve.
Fil. to Scalenus medius.
I Fil
to Supra-clavic. N.
A nterior
Divisions of
ist Cerv. N.
2d Cerv. N.
3d Cerv. N.
4th Cerv. N.
Cervical
Plexus.
Superficial
Deep Brs.
(See page 227.)
Occipitalis Minor, to head.
I Facial.
Auricularis Magnus j Auricular.
( Mastoid.
Superficialis Colli, has 2 branches.
I Vagus.
Communicating to j Hypoglossus.
| Sympathetic.
Muscular, to ant. rectus and rect. later.
Communicans Hypoglossi N. 2.
Phrenic Nerve, to the diaphragm.
Muscular 4, to Sterno-mastoid, etc.
[ Communicating, to Spinal accessory.
THE SPINAL NERVES. Hate 11
Cervical Plexus.
Potter .del
/lCfo/r/fff{
The Cervical Plexus
i... iu ( Scalenus Medius and \ .
lies upon the Muscles
ILevator anguli Scapulae I
is covered by the Sterno-Cleido-Mastoid Muscle
255
256
HUMAN ANATOMY
o
THE BRACHIAL PLEXUS
(See page 228.) Communicating Br. to phrenic nerve.
Post, or Long Thoracic, I to
the Ext. Respiratory I Serrat.
N. of Bell. { mag.
, f Supra-spinatus.
Supra-scapular, T , .
^ < Infra-spmatus.
I Shoulder-joint.
Rhomboidei (5, 6, Cerv.)
Subclavius (5, 6. Cerv.)
Scaleni (6, 7, Cerv.)
Long, colli (6, 7, Cerv.)
Lev. ang. scap. (5, Cerv.)
Ant. Div.
5th
Cervical
Nerve.
Ant. Div.
6th
Cervical
Nerve.
Ant. Div.
7th
Cervical
Nerve.
Ant. Div.
8th
Cervical
Nerve.
Ant. Div.
ist
Thoracic
Nerve.
UPPER
PRI-
MARY
CORD.
LOWER
PRI-
MARY
Brach-
ial
Plexus, i
OUTER
or LAT-
ERAL
CORD.
to
Muscu-
lar, to
POSTERIOR
CORD.
INNER or
MEDIAL
CORD.
f Br. to Post. Cord of Brachial Plexus.
External Ant. Thoracic, to Pect.
major.
f Muscular.
Musculo-cutaneous. I Anterior.
(No. 2.) | Posterior.
[ Articular.
Median Nerve (outer head) (No. 3).
ist Sub scapular, to Subscap. M.
2d Subscapular, to Lat. dorsi.
3d Scapular, to Teres major.
Circumflex, to Deltoid and skin.
(n. Axillaris.)
Musculo-spiral f Muscular<
(No. 6).
(n. Radialis.)
Cutaneous.
Muscular,
to
Post. Interosseous.
[ Scaleni (8, Cerv.)
| Long, colli (8 Cerv.)
I Above Clavicle.
Br. to Post. Cord of Brachial Plexus.
Int. Ant. Thoracic, to Pectoral
muscles.
Internal Cutaneous (No. 8) (medial
Anti-brachial cutaneous).
Lesser Int. Cutan. (N. of Wrisberg)
(medial brachial cutaneous).
Median Nerve (inner head) (No. 3).
Ulnar Nerve (No. 10).
Note. — Nos. i, 2, 3, etc., refer to the next two tables.
THE SPINAL NERVES
Brachial Plexus
Ulament from
Plate 12
Cv
/. Three <Sub- scapular JVerm.
2. Internal Ant. Thoracic.
Potter del
Jtfusculo-cutaneous
'Median.
Wnar
Jnternal-culaneouj
The Brachial Plexus is
in the Neck and the Axilla,
lym^ between the Anterior
and Middle Scaleni muscles
at first- then below the Sub-
clavius and upon the 1^
serration of theSerratus
Magnus and Subscapulans.
It is on both sides of. and
behind the Axillary Artery
in its 2nd Portion, external
.thereto in its Ist Portion.
17
257
258
HUMAN ANATOMY
NERVES OF THE UPPER EXTREMITY
TERMINAL BRANCHES OF THE BRACHIAL PLEXUS
(i) EXTERNAL ANTERIOR THORACIC, to Pectoralis major muscle.
f Coraco-brachialis.
Muscular, to.. •{ Biceps.
[ Brachialis anticus.
i
f Skin of forearm (front).
8
Anterior Br. -1 Skin of ball of thumb.
1
(2) MUSCULO-
{ Joins Radial Nerve.
CUTANEOUS.
a
Skin of forearm (back).
1
Posterior Br.
Joins Radial Nerve.
Joins Ext. Cutan. Br. of Musculo-
3
spiral N.
-8
Articular Br., to Elbow- joint.
o
f Pronator radii teres.
|
Muscular, to . .
Flex, carpi radialis.
Palm, longus.
' 6
Flex. subl. digitorum.
\
1
c
A nterior
Interosseous.
to Flex. long, pollicis.
to Flex. prof, digit. (Ext. H).
to Pronat. quadratus.
Palmar I Skin of palm.
Cutaneous. \ Skin of ball of thumb.
(3) MEDIAN, from
both outer and
to Abduct, pollicis.
inner cords.
to Opponens pollicis.
•A
External Br...
to Flex. brev. pollicis.
§
Digital, to thumb.
W
Digital, to ist finger.
V
a
c
Digital, to contiguous sides of in-
M
Internal Br. ..
dex, middle and ring fingers.
Filaments, to two outer Lum-
bricales.
THE SPINAL NERVES. Piste 13.
250
26o
HUMAN ANATOMY
NERVES OF THE UPPER EXTREMITY. — Continued.
ist, Upper, to Subscapular muscle.
U)SuBSCAPULAR3 { 2d, Long, to Latiss. dorsi.
3d, L'ower, to Teres major.
(5) CIRCUMFLEX
(n. Axillaris).
/ Deltoid.
Superior Br..to < „, . ,
\ Skin of i
Skin of shoulder.
Teres minor.
Inferior Br..to -j Deltoid (posteriorly).
Skin of shoulder.
(6) MUSCULO-
SPIRAL (n.
Radialis).
Muscular ... to
f Triceps. Anconeus.
I Brach. anticus.
I Supin. longus.
[ Extensor carpi long.
Cutaneous, to skin of arm.
f External Br. to skin of thumb.
Radial,
] Internal Br.
I to ulnar side of thumb and ad-
\ jacent sides of 2^ fingers.
ito all muscles on back of forearm,
except Anconeus, Sup. long, and
Extensor carpi longior.
Filaments to wrist-joints.
(7) INTERNAL ANTERIOR THORACIC, to both Pectoral muscles.
(8) INTERNAL CUTANEOUS ( Anterior Br. to skin of forearm, inner side,
(med. Ant. Brach. Cuta.) \ Posterior Br. to skin of forearm, inner side.
(9) LESSER INTERNAL CUTANEOUS, f Is often wanting, Intercosto-humeral
(N. of Wrisberg.) -j taking its place, to post, surface of
(medial Brach. Cutan.) 1 lower H of skin of arm.
Articular, . .
. . to Elbow-joint.
i
Muscular, . .
f Flex. carp, ulnaris.
' ° \ Flex. prof. dig. (inner }£)
8
£ '
c
Cutaneous, to skin of front wrist, and palm of hand.
Dorsal Cutaneous, to skin of back wrist, and iji fingers.
(10) ULNAR
Articular, . . .
. to Wrist-joint.
i
rt
a
i— i
Superficial
Palmar, , . .
( Palmaris brevis.
to\ Skin of iH fingers.
(Muscles of little finger.
2 inner Lumbricales.
InterosseL
Dt.r.t "Pn.lm.nv
Adduc. pollicis.
Flex. brev. poll, (inner headV
THE THORACIC NERVES
26l
THE THORACIC NERVES
N. B.—Read from the Black Types outwards to left and right
Transv. colli.
Muscu- { Intercos.
Longis. dorsi.
lar. \ Tri. Ster.
Trachelo-mast.
Ext. Brs.
Levat. costar.
<— to
Skin of
Sacro-lumbal.
{ Each of 1
ANT.
Lateral
Chest,
Aocessorius.
POST.) Upper 6 1
Div.
Cutane-
Breast.
Div. | Thoracic |
Thoracic
ous.
Side,
I Nerves. J
Inlercostals.
Back.
Semi-sp. dorsi.
r Int. Brs.
A nterior
f Skin of
Multif. Spinae. •
«— tO
Cutane- <
Chest,
Skin of back.
ous.
, Breast.
Muscu- ( Intercos.
Same as above.
. Z7..J D— -
ANT.
lar. \ Abdom. M.
Skin of back.
* iLxt. &rs.
Div. or
(Each of 1
Thorac-
Lateral ( Skin of
Lower 6 1
ico-ab-
Cutane- j
Abdomen,
Thoracic J
dominal
ous. { etc.
Same as above.
\,
Nerves. J
Inter-
No. br. of skin. >
> Int. Brs.
costal*.
Anterior ( Recti M.
Cutane- j Skin of
ous.
Abdomen.
1 2th
Thoracic
•ANT. Div.
/Also sends a branch to
1 the Lumbo-sacral Cord.
262
HUMAN ANATOMY
THE LUMBAR AND SACRAL NERVES
(See page 232)
(DISTRIBUTION SHOWN ON THE NEXT TWO TABLES)
An | 1
[ Nos.
^^ Branch, g Ist Lumbar / Ant. i, 2, 3,
sending filaments > [ Div. | Comm. Br.
to the Erector g J
( to 2d Lum.
spinae and o
Intertransversales JB 1
Nos.
muscles, and the ^
skin of the gluteal ° ^ Lumba,
. f Ant. 3, 4, 7,
\ Div. Comm. Br.
region, posteriorly. ^ J
to 3d Lum.
Lumbar Plexus.
3
Branches:
1 1
{Part of
(i) Ilio-hypogastric.
5, 6. 7,
(2) Ilio-inguinal.
Internal Branch, -J3 | 3
Comm. Br.
(3) Genito- crural.
sending filaments Q J
to 4th Lum.
(4) Ext. Cutaneous.
to the Multifid. ^
(5) Obturator.
spinae, and Inter- -g
f Part of
(6) Accessory
spinales, and the -g
skin over spinal £ j- 4th Lumba
/Ant. r5'V
r. < ^. Lumbo-
Obturator.
(7) Anterior Crural.
vertebras. <u
* 1V' 5acra/
e J
Cord
\
r A., f Joins the '
g [ 5th Lumbar. < ""T { Lumfeo-
4« - J
[ Sacra/ Cora1
External Branch,
forming loop on £
f Joins the
sacrum and great c
/ Ant Lumbo-
Sac-Sciat. lig. to g ist Sacral.
1 nj^ Sacra/ Cord
supply skin over £
I •L'lv. j
and
glutei. "3
2d Sacral.
* [ad Sacral.
"8
/ Ant. / Joins with
\ Div. \ ist Sacral.
Sacral Plexus.
Branches:
a
(i) Sup. Gluteal.
An 1
f Joins with
(2) Inf. Gluteal.
Internal Branch, > I
to Multifidus Spinae S |3d
2d Sacral
and part
(3) Muscular.
(4) Articular.
and skin of the £ J
[ of the 4th.
(5) Small Sciatic.
gluteal region; the %
(6) Pudic.
lower nerve to g
Br. to
(7) Great Sciatic.
Extensor Coccygis &
f Ant PleXUS>
and skin over the jg 4th Sacral.
i Div Visc'Brs-
coccyx.
Mus. Brs.
J
Fil. to 5th. .
Join together in
loops over back Post. \
of sacrum, Div./5* SaCraL
/ Ant. ( Br. to skin of coccyx.
\ Div. j Br. to Coccygeus M.
sending fila-
[ Br. to Cocc. Nerve.
ments to skin
over coccyx Post. \ _
f Ant. / A delicate filament, going to skin
and Extensor Div. /
\ Div. \ over coccyx.
Coccygis.
Plate 14
THE SPINAL NERVES.
lumbar & Sacral Plexuses.
The lumbar Plexus lies in the Substance of the Psoas Muscle
( Lies upon the Pyr iformis Muscle in the Pelvis
The Sacral Plexus {and is covered by the Pelvic Fascia, and the
V Sciatic and Pudic Arteries.
Potter, del
264
HUMAN ANATOMY
ILIO-HYPOGASTRIC,
from ist Lumbar.
DISTRIBUTION OF THE BRANCHES
FROM THE 7 GREAT TRUNKS OF THE LUMBAR PLEXUS
(A CONTINUATION OF THE TABLE ON PAGE 261)
f Iliac, to skin of gluteal region.
j Hypogastric, to skin of that region.
( Communicating Br., with I2th thoracic nerve.
ILIO-INGUINAL,
from ist Lumbar.
Branch, to ilio-hypogastric nerve.
to Internal Oblique muscle.
to skin of upper and inner thigh, scrotum.
GENITO-CRURAL, \ Genital, to Cremaster, scrotum, round ligament,
or GENITO-FEMORAL <j Crural, to skin of upper and front thigh,
from ist, 2nd Lumbar. [ Branch, to femoral artery.
EXTERNAL CUTANEOUS, ( Ant. Br. to skin of ant. and outer thigh,
from 2nd, 3d Lumbar. \ Post. Br. to skin of post, and outer thigh.
OBTURATOR,
from 2d, sd
4th Lumbar.
Ant. I" Articular Brs. to hip-joint.
Br. j Muscular Brs. to Adductors, Gracilis and Pectineus.
[ Anastotnotic Brs. with Int. Cutan. and Int. Saphenous.
Post. \ Articular Brs. to knee-joint.
Br. \ Muscular Brs. to Adduc. mag. and Obturator externus.
ACCESSORY OBTURATOR,
from 3d, 4th Lumbar.
Muscular Br. to Pectineus.
Articular Br. to hip- joint.
f often absent.
Cutaneous Br. to skin of thigh and leg. J
Muscular Brs. to Iliacus muscle.
Arterial, to the femoral artery.
> within abdomen.
ANTERIOR
Mid. Cutaneous.
to Sartorius, and skin of ant. thigh
as low as the knee.
FEMORAL or
Ant.
Ext. Br. to skin, lateral of knee.
CRURAL,
Div.
Int. Cutaneous.
Post. Br. to skin of inner thigh and
from 2d, 3d,
leg.
4th Lumbar.
Long Saphenous.
to skin of knee and of front and
inner leg and foot.
p | Muscular Brs. to the 4 parts of the Quadriceps Extensor
*£T j muscle.
V' [ Articular Brs. 2, to capsules of knee- and hip-joints.
The Lumbar Plexus lies in the substance of the Psoas muscle, in front of the trans-
verse processes of the lumbar vertebrae.
THE SPINAL NERVES.
Plate 15
Potter, del
266
HUMAN ANATOMY
DISTRIBUTION OF THE BRANCHES OP THE SACRAL PLEXUS
[CONTINUATION OF TABLE ON PAGE 261]
SUPERIOR GLUTEAL,
from Lumbo-sacral cord. I Inf. Br.
Sup. Br. to the Gluteus medius muscle.
to the Gluteus medius and minimus,
to the Tensor vaginae femoris.
INFERIOR GLUTEAL,. .to the Gluteus maximus muscle.
MUSCULAR BRANCHES, to
Pyriformis, Obturator internus, the two Gemelli, and
the Quadratus femoris muscles.
ARTICULAR BRANCHES, to the hip- joint.
SMALL SCIATIC,
or POSTERIOR
FEMORAL
CUTANEOUS,
from 2d, 3d Sac-
ral.
Gluteal Cutaneous, to skin over Gluteus maximus.
Perineal Cutaneous, *° ^ * "Pf ^ and finner thigh'
[ Inf. Pudendal, skin of scrotum.
Femoral Cutaneous
0 back °f thigh, popliteal space, and
upper part of the leg.
PERFORATING f
CUTANEOUS, 1 to skin covering lower part of Gluteus maximus muscle: passes
from 2d, 3d Sac- ] through the sacro-sciatic ligament.
ral.
PUDIC or
PUDENDAL,
from 3d, 4th
Sacral.
GREAT SCIATIC
(n. ischiadicus),
from lumbo-sac-
ral cord, 4 upper
sacral.
Inferior Hemorrhoidal,
to Sphincter ani muscle,
to skin of anal region.
(to Skin of anus, scrotum,
Superficial Perineal, -j penis and labia, and the
( Sphincter ani muscle.
Muscular, to perineal muscles, and corpus spongio-
sum of penis.
Dorsal of Penis,
Skin of dorsum of penis.
Br. to Corpora cavernosa.
Articular,, .to the hip-joint.
Adductus magnus, Biceps.
Muscular, to
Semi-mem branosus, Semi-tendinosus.
External Popliteal or Peroneal. \ terminal branches.
Internal Popliteal or Tibial Nerve. } (See next page.)
The Sacral Plexus lies in the pelvis upon the Pyriformis muscle, and is covered
by the Pelvic fascia, and the Sciatic and Pudic arteries.
NERVES OF THE LEG AND FOOT
267
INTERNAL
POPLITEAL
or TIBIAL
NERVE.
NERVES OF THE LEG AND FOOT
TERMINAL BRANCHES OF THE GREAT SCIATIC NERVE]
Articular 3, to knee-joint.
Muscular, to Gastrocnemius, Plantaris, Soleus, and Popliteus.
Communicans Tibialis, to form the Ext. Saphenous nerve.
I formed by a filament from each of the
External or Short Saphenous, j Popliteal nerves, to skin of outer
1 side of the foot and little toe.
Continues
as the—
POSTERIOR
TIBIAL.
Muscular, to
Flexor longus pollicis. Flexor longus digitorum.
Tibialis posticus. Soleus.
Calcaneo-Plantar, to skin of heel and sole of the foot.
Articular, to the ankle-joint.
I Digital, to skin, 3^ inner toes.
Internal I Muscular, to flexors, etc.
Plantar. J Articular, to tarsal joints.
I Cutaneous, to sole of foot.
External
Plantar.
Muscular, to Flexor accessorius.
f to I ^j outer toes.
Superficial, < Flexor brevis min. digiti.
[ 4th Interosseous.
Deep Br. to the
3d and 4th Lumbricales.
rest of Interossei.
EXTERNAL
POPLITEAL
or COMMON
PERONEAL
NERVE.
Articular 3, distributed to the knee-joint.
Cutaneous 2, to skin of leg, exteriorly and posteriorly.
Communicans Peronei, to form the Ext. Saphenous nerve.
/ front muscles of leg.
Anterior
Tibial cr
Deep Pero-
neal
Musculo-
cutaneous or
Superficial
Peroneal.
Muscular, to
External Br.
\ Peroneus tertius.
/ Extensor brevis digitorum.
\ Tarsal articulations.
Internal Br. to skin of sides of great and 2nd toes.
External Br.
Peroneus longus and brevis muscles.
Skin, outer side of foot and ankle.
Skin, contig. sides, 3d, 4th, 5th toes.
[ Skin, inner side of foot and ankle.
Internal Br. -j Skin, contig. sides, ad and 3d toes
[ and inner side of great toe.
268
HUMAN ANATOMY
Begins in
the—
1 Ganglio
/ of Ribes
External
Sup.
Branches
Brs.
to join the
ist, 2d,
Superior
3d, 4th
Cervical •
Anter
Cervical
Ganglion.
Nerves.
THE SYMPATHETIC SYSTEM
n f on the Anterior Communicating artery, at the base of
es. \ the brain.
[ Some to Pneumogastric, Glossopharyngeal, and
Hypoglossal Nerves.
(Ext. Br. forms Carotid Plexus.
Int. Br. forms Cavernous Plex.
along Int. Carotid Artery.
Anterior Branches, to Plexus on Ext. Carotid Artery.
f Pharyngeal, to Pharyngeal Plexus.
Int. I Superior Cardiac Nerve, to Cardiac Plexus; goes
Brs. I to Deep PI. on right side, to Superficial PI.
[ left side of body.
Ext. Brs. to f Middle
5th and 6th j Cervical
Cerv. N. [ Ganglion.
Ext. Brs. to f Inferior
7th and 8th X Cervical
Cerv. N. [ Ganglion.
Int.
Brs.
(Filaments along Inf. Thyroid Art. to Thyroid
•j body and Larynx.
[ M id. Cardiac Nerve, to Deep Cardiac Plexus.
Int. ( Filaments along Vertebral Art. to cranium.
Brs. \ Inf. Cardiac Nerve, to Deep Cardiac Plexus.
Ext. Brs. to
Thoracic
N.
f " 1
•j Thoracic j-
[ Ganglia. J
Int.
Brs.
Upper 5 or 6 to Aorta and Vertebral column.
3d and 4th to Post. Pulmonary Plexus.
Lower 6 form the 3 Splanchnic Nerves, thus —
6-10, Great Splanchnic, to Semi-lunar Gang.
10, ii. Lesser Splanchnic, to Cceliac Plexus.
12, Smaller Splanchnic, to Renal and Solar
Plexuses.
Ext. Brs. to
Lumbar N.
4
Lumbar
Ganglia.
lnt. 1 Some to Aortic Plexus.
Brs. \ Some to Hypogastric Plexus.
Ext. Brs. to
Sacral N.
4 or 5
Sacral
Ganglia.
Int
Brs
'. f to Pelvic Plexus.
rs. \ to Plexus on Middle Sacral Artery.
{Coccygeal )
G., or I In which ends the double chain of gangliated cords
Ganglion j enumerated above, and called THE SYMPATHETIC NERVE.
Impar. .
[FOR THE VARIOUS CONNECTED GANGLIA, ETC., SEE PAGES 223 TO 22?.]
THE SYMPATHETIC
SYSTEM OF NERVES
Plate 16
tcG.ofRootofPncu
toftlrvas G.
Glasso-pha
from &Cervica
•2
G^GANGLIOTJ
umogastric
toflypoylos&al N.
br. cf£xt. Carotid A .
toPharyntjeal P.
to Inf. 'Thyroid 4*
Cardiac bT.Jr.PneumogastTic f?= PLEXUS .
and Rec. Larynyeal "Nerves AJ=ARTERY.
"Cardiac Fiexns
Mexua
duodenal
/. Sup. HemorrhoidaL P.
2.Spcrmatic Plexus
rpoaa&tric Plexus
Pelvic or Inf. ' ffypcyra&tnc Plexn*
Oarujlumlmpar. ^ Twt«r del.
26<)
2 7o
HUMAN ANATOMY
FIG. 81.
ORGANS OF SPECIAL SENSE
The Special Senses are those of touch, taste, smell, sight and hearing.
The Skin is the principal seat of the sense of touch, the Tongue is the organ
of taste, the Nose is the peripheral organ of smell, the Eye of sight and the
Ear of hearing.
THE SKIN AND ITS APPENDAGES
The Skin consists of — the Epidermis or Cuticle, the scarf-skin, com-
posed of 3 superficial and 2 deep layers; and the Derma, Corium, or Cutis
Vera, the true skin, composed of a
papillary layer above and a reticular
layer below.
The Epidermis, Cuticle or Scarf-
skin, is an unorganized epithelial
structure, having neither vessels nor
nerves. Its constituent epithelial
cells are agglutinated together in a
laminated arrangement, are flat and
dry on the surface, round and softer
in the central portion, columnar and
softest in the deepest layers. They
are arranged in the following layers,
from above downward, viz. —
Stratum Corneum (i), — horny epi-
thelial cells, without nuclei.
Stratum Lucidum, — closely packed,
scaly cells.
Stratum Granulosum, — flat, spin-
dle-shaped cells, containing
granules of eleidin, an interme-
diate substance in the forma-
tion of horn.
Rete Mucosum or Stratum Mal-
pighii (2), — contains pigment
cells.
Basilar Layer or Stratum Germinativum, — composed of columnar
epithelial cells placed perpendicularly on the surface of the derma, and
separated from the papillae by a homogeneous basement membrane.
The Derma, Corium or Cutis Vera (4), the true skin, is a highly organized,
tough yet elastic tissue, and serves to protect the parts beneath, to perform
APPENDAGES OF THE SKIN 271
the functions of excretion and absorption, and as the chief seat of the sense
of touch. It consists of felted connective tissue, elastic fibres, blood-
vessels, lymphatics, and nerves; also unstriped muscular fibres in various
situations. It is formed in two layers, as follows: —
Papillary Layer (3), — situated next to the epidermis, is covered with
minute conical elevations (papillae), H^oo inch high, ^50 inch in
diameter at their base, very numerous and arranged in parallel
curved lines wherever sensibility is greatest. Each papilla contains
a capillary loop or plexus, the termination of one or more sensory
nerves, — and in highly sensitive parts, an oval-shaped body, the
Tactile Corpuscle, a special sensory nerve ending.
Reticular Layer, — the deep layer, is composed chiefly of interlacing bun-
dles of white fibrous tissue, in which are mingled some yellow elastic
fibres; also plain muscular fibres wherever hairs are found, and lym-
phatic vessels, blood-vessels, and nerves in plexiform arrangement.
Below this the elements of the skin become blended with the sub-
cutaneous tela or areolar tissue (5), which contains fat, except in a few
situations.
Mucous Membrane is a soft, velvety structure, analogous to the skin,
and found as the lining of the gastro-intestinal, pulmonary and genito-
urinary tracts. It is composed of — Epithelium of various forms, in-
cluding the squamous, columnar, and ciliated, often arranged in several
layers; and Corium, analogous to the derma of the skin, consists of con-
nective tissue, blood-vessels, lymphatics, nerves, and unstriped muscle
cells; and is separated from the epithelium by a transparent basement
membrane. The mucous membrane has numerous glands embedded in
it, which secrete mucus to cover the surface for its protection from foreign
substances. Projecting from it in certain parts are villi and papilla.
processes which are analogous to the papillae of the skin.
Structures lying in the Skin, and directly beneath it, include the follow-
ing, viz. —
Sensitive Papilla, containing Tactile Corpuscles in very sensitive parts, —
in the papillary layer of the derma.
Hair Follicles, — in the reticular layer of the derma, perforating the
derma and the epidermis: sometimes extending into the subcutaneous
tissue.
Sebaceous Glands (6), — in the reticular layer of the derma; their ducts
(8, 9) opening usually into the hair-follicles, but occasionally on the
surface of the epidermis.
Sudoriferous or Sweat Glands, — usually in the subcutaneous areolar
272
HUMAN ANATOMY
FIG. 82.
tissue; their ducts perforating the derma and epidermis, to open on
the surface of the latter.
Fat Cells, — in the subcutaneous areolar tissue.
Organs of Touch are the various sensory nerve-
endings in the skin or its vicinity and in mucous
membranes. They include minute, primitive
fibrilla or networks thereof, and certain special
terminal organs, as follows: —
End-bulbs of Krause, — minute bodies, Moo
inch in diameter, consisting of a capsule
surrounding a soft core, in which the axis-
cylinder of the nerve terminates, in a bulbous
expansion or in a coiled plexiform mass.
They are found chiefly in mucous mem-
branes, the genital organs, and the synovia]
membranes of the finger-joints.
Tactile Corpuscles, — are oval bodies, ^oo inch
long, formed of connective tissue, and con-
sisting of a capsule and imperfect septa, which penetrate the interior.
The axis-cylinders of the nerve fibres (N) terminate within the
corpuscle in a globular enlargement. They are found in papillae of
the derma of the hand, foot, forearm, lips,
nipple, etc. Other tactile corpuscles, in
the papillae of parts devoid of hair, consist
of a capsule, containing two or more
granular cells, between which the nerve-
fibre is supposed to terminate.
Pacinian Corpuscles, — are composed of
lamellae (d), consisting of connective
tissue fibres, arranged concentrically
around a central clear space (ni), in which
the nerve-fibre (n) terminates at the distal
extremity in a rounded end (a), which is
often bifid or even trifid. They are found
chiefly on the nerves of the palm of the
hand and the sole of the foot, the ends of
the fingers, and the genital organs, lying
in the subcutaneous tissue.
APPENDAGES or THE SKIN
The Nails (Ungues) are curved, horny structures, a modification of the
epidermis, molded upon the derma at the dorsal surface of the terminal
FIG. 83.
THE TONGUE 273
phalanges of the fingers and toes. Each nail is convex on its outward
surface, and is embedded by its Root (radix unguis) into a fold of the skin.
Its—
Matrix, — is that portion of the derma directly beneath the nail. It is
covered with highly vascular papillae. The —
Lunula, — is a white crescentic portion of the nail nearest to its root,
produced by the diminution in number and size of the papillae beneath.
The Hairs (Pili) are also a modified form of the epidermis, found over
nearly the whole surface of the body, much varied in size and color. Each
hair consists of a Root and a Shaft. The —
Root (radix pili), — is lodged in an involution of the epidermis called the
Hair-follicle, which sometimes extends into the subcutaneous cellular
tissue. The root rests on a vascular papilla, at the bottom or Bulb
of the follicle, which supplies it with material for its growth.
Shaft (scapus pili), — is the projecting portion of the hair. It consists
of a medulla in the centre, next a fibrous portion, externally a cortex
of thin, flat scales. The finest hairs have no medulla.
Point (apex pili), — consists of the fibrous portion and the cortex, the
medulla being wanting.
Sebaceous Glands (Glandulae Sebaceae) are small, glandular bodies
situated in the corium over most of the body, but not in that of the palmar
surface of the hands nor on the plantar surface of the feet. Each gland
consists of a single sacculated duct, usually opening into a hair-follicle,
but sometimes ending on the surface of the epidermis. They are most
abundant in the scalp, the face, around the anus, and the apertures of the
nose, mouth and external ear. The largest are the —
Meibomian Glands, — situated in the eyelids.
Sudoriferous or Sweat Glands (Glandulae Sudoriferae) consist each of a
single convoluted tube, situated usually in the subcutaneous cellular
tissue, and opening on the surface of the integument by a spiral duct
which pierces the derma and the epidermis. The duct has two coats, an
external fibro-cellular, which is continuous with the corium, and an
epithelial lining, continuous with the epidermis. These glands are
estimated as varying, in different parts of the integument, from 417 to
2800 to the square inch, giving for the whole body a total number of nearly
two millions and a half, representing an evaporating surface of about 8
square inches. They are most numerous on the palm of the hand.
THE TONGUE (LINGUA)
The Tongue is the organ of taste. It is composed of siriated muscle,
is covered with mucous membrane, and is supplied with blood-vessels,
18
274
HUMAN ANATOMY
lymphatics and nerves. Its base (radix linguae) is connected with the
hyoid bone by the hyo-glossi and genio-hyo-glossi (mm. genioglossi)
muscles and the hyo-glossal membrane; with the epiglottis, by the 3
gJosso-epiglottic folds of mucous membrane; with the soft palate, by the
anterior pillars (arci glosso-palatini) of the fauces; and with the pharynx,
by the superior constrictor muscles and the mucous membrane. Its tip
(apex linguae), thin and narrow, is free in the mouth, and rests when
quiet against the lower incisor teeth. Its wider surface (facies inferior
linguae) is connected with the lower jaw by PIG
the genio-hyo-glossi (mm. genioglossi) mus-
cles. Its mucous covering is reflected later-
ally on the inner surface of the gums, form-
ing in front the frjEnum lingua (frenulum lin-
guae), a vertical fold below the tip. The
tongue presents the —
Raphe (sulcus medianus linguae), — a ver-
tical, fibrous septum, in the median line,
dividing the tongue into two symmet-
rical halves, and terminating behind in a
depression, the foramen ctzcum, about an
inch from the base of the organ.
Papillcs V dilates (i) (circumvallate), — 8 to 12
in number, in two rows on the dorsum of
the tongue, the rows forming a V and
meeting in front of the foramen cacum.
Papilla Fungiformes (2) (lenticular), —
scattered irregularly over the dorsum,
chiefly at its sides and apex.
Papilla Filiformes (conical), — cover the anterior two- thirds of the
dorsum and' have numerous filiform processes or secondary papillae
projecting from their apices.
Taste-buds, — flask-shaped bodies, found in the epidermis of the circum-
vallate papillae, and in some of the fungifqrm (described below).
Glands of Blandin or Nuhn, — mucous glands, one on either side of the
fraenum, having 4 to 6 ducts which open on the under surface of the
apex.
Racemose Serous Glands of Ebner, — at the back of the tongue, their ducts
opening into the fossae of the vallate papillae.
Hyo-glossal Membrane, — a strong, fibrous lamina, connecting the under
surface of the base of the tongue to the bod> of the hyoid bone.
Extrinsic Muscles of the Tongue, — are the stylo-, hyo-, chondro-, genio-
THE TONGUE 275
hyo-, palato-glossi muscles, and part of the superior constrictors of
the pharynx (pharyngeo-glossi). These have been described on
page 82.
Intrinsic Muscles of the Tongue, — are the various fibres of the lingualis
muscle, — superior, inferior, transverse and vertical. (See page 83.)
Taste-buds are flask-shaped bodies, situated in the epidermis (e) of the
vallate and some of the fungiform papillae; also found at the sides of the
base of the tongue, on the epiglottis and the soft palate. Each bud has a
broad base, which rests on the corium, and a neck opening on the mucous
surface by an orifice, the gustatory pore (0). The buds are formed by sup-
porting cells, mostly arranged like the staves of a
cask; and spindle-shaped, nucleated gustatory cells
in the central portion, each terminating at the
gustatory pore in a fine filament, the gustatory
hair. Terminal nerve-fibrils ramify between the
gustatory cells, and others are found between the
cortical cells.
Vessels of the Tongue. The Arteries are de-
rived from the lingual, facial, and ascending
pharyngeal, branches of the external carotid.
The^ Veins open into the internal jugular. The
Lymphatics of the posterior half of the tongue
pass to one or two small glands on the hyo-glossus
muscle, and thence to the deep glands of the neck;
those of the anterior half are connected with the sub-mandibular
lymphatics.
Nerves of the Tongue are as follows: the —
Lingual Branch of the Mandibular Division of the $th, — to the papillae of the
fore part and sides of the tongue, endowing the anterior two-thirds of the
organ with ordinary sensibility.
Chorda Tympani is the continuation of the glosso-palatine nerve (n. inter-
medius) or "pars intermedia, " the sensory root of the facial, — it runs in
the sheath of the lingual nerve and is distributed to the same region,
being the nerve of taste for the anterior two-thirds of the tongue.
Lingual Branches of the gth or Glosso- pharyngeal, — to the mucous membrane
of the base and sides and the circumvallate papillae, being the nerves of
taste and ordinary sensation for the posterior third of the tongue.
Hypo-glossal or j 2th Nerve, — the motor nerve of the tongue, distributed to
the intrinsic and extrinsic muscles,
276 HUMAN ANATOMY
Superior Laryngeal Branch of the loth or Vagus, — sends a few filaments, by
way of its internal laryngeal branch, to the root of the tongue.
Sympathetic Filaments, — from the nervi molles on the lingual and other
arteries supplying the organ (Spitzka).
Special Nerves of Taste in the Tongue, are the-
Chorda Tympani, the continuation of the sensory root (glosso-palatine
nerve or n. inter medius) of the Facial, — for its anterior two- thirds;
perceiving saline, acid and styptic qualities (Flint).
Lingual Branches of the Glosso-pharyngeal, — for its posterior third; appre-
ciating alkaline, metallic, sweet and bitter tastes (Flint).
Sapolini's view of the Chorda Tympani Nerve. From repeated dis-
sections, Dr. Sapolini, of Milan, believes the chorda tympani to be a
separate cranial nerve, a continuation of the pars intermedia of Wrisberg
(glosso-palatine nerve or n. intermedius) which has its deep origin in the
upper end of the nucleus of the glosso-pharyngeal nerve in the floor of
the 4th ventricle and the solitary or "trineural" tract in the medulla,
joins the facial in the internal auditory meatus, and terminates in a dense
plexus with the lingual branch of the £th in the muscular substance of the
tongue. He further concludes that the chorda tympani is the nerve
governing the movements of the tongue in speech, and that the nerves of
taste are the Lingual Branches of the 5th and gth nerves.
THE NOSE (NASUS)
The Nose is the peripheral organ of smell, and consists of the outer nose
(nasus externus) and the nasal fossae (cavum nasi). The Outer Nose
projects from the centre of the face, and is composed of a framework
of bones and cartilages, covered by skin, lined by mucous membrane, and
supplied with vessels and nerves. At its base it presents two elliptical
orifices, the nostrils or anterior nares, separated by a septum, the columna
(septum mobile nasi), and guarded at their margins by numerous stiff
hairs, the mbrissoe. The —
Bony Framework, — is formed by the nasal bones and the nasal processes
of the maxillae (see page 27).
Cartilages (cartilagines nasi) are 5, — two upper lateral (cartilago nasi
latralis), two lower lateral (cartilago alaris nasi major), and the
cartilage of the septum (cartilago septi nasi), connected together and
to the bones by a tough, fibrous membrane, which permits of free
movement between them.
Septum Nasi, the nasal septum, — is formed anteriorly by the cartilage
THE NOSE
277
of the septum, posteriorly by the perpendicular plate of the ethmoid
bone above and the vomer below.
The Nasal Fossae (cavum nasi) are two irregular cavities in the middle
of the face, separated by the septum nasi, opening in front by the anterior
nares, behind by the posterior nares (choanae) into the naso-pharynx.
Their osteological description has been given on page 37. Each fossa is
divided into an olfactory portion (regio olfactoria), containing the upper
part of the septum and the superior turbinal process and a respiratory
portion (regio respiratoria), comprising the rest of the fossa. It is
further divided, from above downward, into the superior, middle and
16 H 12
inferior meatuses of the nose, which are separated from each other by the
middle (concha nasalis media) (2) and inferior turbinal (concha nasalis
inferior) bones. Each fossa presents the —
Vestibule (9), — a slight dilatation inside the aperture of the nostril,
extending as a small pouch, the ventricle, toward the point of the nose.
Spheno-ethmoidal Recess, — on the outer wall, above the superior tur-
binal process into which the sphenoidal sinus (4) opens.
Bulla Ethmoidalis, — an elevation on the outer wall of the middle meatus,
on or above which are the orifices of the middle ethmoidal cells.
Hiatus Semilunaris, — a narrow groove in the outer wall, in front of
the bulla ethmoidalis, into which open the anterior ethmoidal cells
and the antrum (sinus maxillaris) of Highmore (i) .
Infundibulum (3), — the superior prolongation of the middle meatus,
278 HUMAN ANATOMY
leading into anterior ethmoidal cells and the frontal sinus (see
page 38).
Atrium (atrium meatus medii nasi) (5), — a depressed area above the
vestibule, forming the anterior extremity of the middle meatus.
Orifice of the Nasal Duct (ductus naso-lacrimalis) (7), — on the outer wall,
in the anterior part of the inferior meatus.
Naso-palatine Recess, — a depression at the lower edge of the cartilage of
the septum; near it a minute orifice leads into a blind pouch, the
rudimentary organ of Jacobson (organon vomero-nasale).
The Schneiderian or Pituitary Membrane is the mucous membrane
lining the nasal fossae, thick and vascular over the septum and the
turbinal processes, but very thin elsewhere. On it, in the upper portion of
the fossae, are distributed the terminal filaments of the olfactory nerve, the
FIG. 87.
special nerve of the sense of smell. It is continuous with the mucous lin-
ing of the pharynx, Eustachian tube (tuba auditiva), tympanum and
mastoid cells; also with that of the frontal, ethmoidal and sphenoidal
sinuses, the maxillary antrum, nasal duct, and the conjunctiva. It is
covered with columnar epithelium, which is ciliated throughout most of
its extent, contains much adenoid tissue, is provided with mucous and
serous glands, and in the olfactory region it contains the —
Olfactory Cells of Schultze, — spindle-shaped, epithelial cells, grouped
around and between the columnar cells of the epithelium, having at
THE NOSE 279
one end hair-like processes, the olfactory hairs, and joined together by
other processes, forming an intricate plexus on which the terminal
fibres of the olfactory nerves are supposed to end.
Glands of Bowman, — are tubular, often branched, serous glands, in a
layer beneath the epithelium, extending through the thickness of the
mucous membrane, in the olfactory region.
Nerves supplying the Outer Nose are branches from the facial nerve
to the muscles; branches from the infraorbital and infratrochlear, and the
nasal branch of the ophthalmic, supplying the integument. Those
supplying the Nasal Fossa are the —
Olfactory or ist Nerve (a), — over the upper third of the septum (i), the
superior turbinal process and the surface of the ethmoid in front of it.
Nasal Branch of the Ophthalmic (d}, — to the septum and outer walls.
Anterior Dental or Alveolar Branch of the Maxillary, — to the inferior
meatus of the nose and the inferior turbinal bone.
Vidian Nerve (n. canalis pterygoidei), — to the septum and the inferior
turbinal bone.
Naso-palatine (e), — from the spheno-palatine ganglion, to the middle of
the septum; thence through the anterior palatine foramen (/).
Anterior Palatine (h), — from the spheno-palatine ganglion, to the middle
and lower turbinal bones, by its inferior nasal branches.
Superior Nasal Branches, — from the spheno-palatine ganglion, to the
septum and the superior and middle turbinal bones.
Arteries of the Nose. The arteries supplying the Outer Nose are —
the lateralis nasi branch of the facial (a. maxillaris externa); the inferior
artery of the septum, from the superior coronary branch of the facial
(a. maxillaris externa); and the nasal branch of the ophthalmic and the
infraorbital, which go to the dorsum and sides of the nose. The Arteries
of the Nasal Fosses form a close, plexiform network beneath and in the
mucous membrane, and are the — •
Ant. and Post. Ethmoidal, from the ophthalmic, — to the roof.
Spheno-palatine, branch of the internal maxillary, — to the mucous mem-
brane over the turbinal bones, the meatuses, and the septum.
Infraorbital and Alveolar, branches of the internal maxillary, — to the
mucous lining of the antrum.
Inferior Artery of the Septum, from the superior coronary branch of the
facial (a. maxillaris externa), — to the mucous membrane of the
septum.
.
Veins of the Nose. Those of the outer nose terminate in the facial and
ophthalmic veins. Those of the nasal fossa form a close, cavernous-like
280
HUMAN ANATOMY
network beneath the mucous membrane, and terminate in the facial and
ophthalmic veins, a few going to the veins in the interior of the skull.
THE EYE
[For an osteological description of the Orbit, see page 35.]
The Eyeball (bulbus oculi) is situated in the anterior part of the orbital
cavity, on a cushion of connective tissue and fat, where it is retained by
its muscles, the optic nerve, the conjunctiva, etc., and protected in front
by the eyelids and eyebrows. It is composed of segments of two spheres
of different sizes; the anterior segment being the smaller, forming about
Y§ of the eyeball, and named the cornea; the posterior and larger
segment, is formed by the sclerotic coat
(tunica fibrosa oculi), and constitutes
the remaining % of the globe. It is
surrounded by a thin, membranous sac,
the capsule (fascia bulbi oculi) of Tenon,
and has the following — '<
Diameters, — in the adult, antero-pos-
terior and transverse, nearly an
inch, vertical about %o of an inch.
Anterior Pole, — the central point of
the anterior curvature.
Posterior Pole, — the central point of
the posterior curvature.
Sagittal Axis (axis optica), — a line
joining the two poles.
The Capsule of Tenon (fascia bulbi
oculi) (3) is a thin membrane which en-
velops the eyeball from the optic nerve
to the ciliary region, where it blends with the ocular conjunctiva. Its
smooth, inner surface is in contact with the outer surface of the scler-
otic coat (tunica fibrosa oculi), with which it is connected by delicate
bands of connective tissue. Posteriorly it is continuous with the sheath
(17) of the optic nerve, and from it tubular sheaths are prolonged over
the muscles which move the eyeball, giving off slips to the bones of the
orbit. The —
Check Ligaments, — internal and external, are expansions from the
sheaths of the internal and external recti muscles, and are attached
to the lacrimal and malar bones respectively.
THE EYE 28l
Suspensory Ligament of the Eye (Lock wood's), — is a thickening of the
lower part of the capsule, slung like a hammock below the eyeball,
and attached to the lacrimal and malar bones.
Peri-sclerotic Lymph-space, — intervenes between the capsule and the
sclerotic, and is continuous with the subdural and subarachnoid
spaces.
Tunics of the Eyeball are 3 in number, named from without inward as
follows: the —
; Sclerotic (fibrosa) (3) and Coronea (i), — the external, fibrous, and
protective tunic.
Choroid (choroidea) (4), Ciliary Body (corpus ciliare) (5), and Iris (8),
— the vascular tunic, sometimes called the Uveal Tract.
Retina (tunica interna) (13), — the innermost, nervous tunic.
Refracting Media are 3 in number, and are named as follows: the —
Aqueous Humor (humor aqueus) (2), ^fills the anterior (2) and posterior
(9) chambers (camerae).
Vitreous Body (corpus vitreum) (18), — fills the concavity of the retina.
Crystalline Lens (lens crystallina) (15), — in front of the vitreous body.
THE SCLEROTIC AND CORNEA
The Sclerotic, or hard coat (tunica fibrosa oculi), is the posterior five-
sixths of the jjx.t£rnal iunic of the eyeball, the anterior one-sixth being the
Cornea. Externally it is of a whita-color, covered anteriorly by the
conjunctival mucous membrane, posteriorly being continuous with the
fibrous sheath of the optic nerve. Internally its color is brown, and its
surface marked by grooves for the ciliary nerves. The optic nerve pierces
it posteriorly, also the long and short ciliary arteries, posterior ciliary
veins and short ciliary nerves. In the equatorial region it is pierced
obliquely by the venae vorticosae, and around the corneal border by the
anterior ciliary arteries and veins. It is composed of white fibrous tissue,
intermixed with elastic fibres, and of flattened connective-tissue corpuscles,
some of which are pigmented. The Sclerotic presents for consideration
the following points: —
Thickness, — ^5 inch posteriorly, %o inch anteriorly.
Lamina Fusca, — a layer of very fine pigmented connective tissue, con-
necting the sclerotic with the outer surface of the choroid.
Lamina Cribrosa (lamina cribrosa sclerae), — the posterior perforated
portion of the sclerotic, which at this point is a thin, cribriform
lamina. Its largest opening transmits the arteria centralis retinae.
282 HUMAN ANATOMY
Arteries, — from the ciliary, are few and in a coarse network, the
capillaries uniting at long and wide intervals.
Nerves, — from the ciliary, their mode of ending unknown.
The Cornea, or horny body, is the anterior transparent projecting
portion of the external tunic of the eyeball, forming about one-sixth
thereof. It is set into the sclerotic as a watch-crystal into its case, is of
nearly circular base, and its curvature varies in degree in different persons,
and in the same person at different ages, becoming flattened in advanced
life. It consists of 4 layers, — centrally the true fibrous corneal tissue,
having in ^ront the conjunctival epithelium; behind, a homogeneous
elastic lamina and thyepithelial lining of the anterior chamber. The —
Conjunctival Epithelium, — consists of several layers of epithelial cells,
the deepest being columnar, the central polyhedral with processes
and the superficial scaly with flattened nuclei.
Jj Proper Corneal Substance, — a transparent, firm, fibrous structure, con-
tinuous with the sclerotic, and composed of about 60 lamella of
modified connective tissue, superimposed one on the other, and
connected by a cement, in which are spaces of stellate shape, each
containing a cell, the corneal corpuscle. The anterior layer of the
corneal substance was called by Bowman the anterior elastic lamina.
Posterior Elastic Lamina, Membrane of Descemet, or Demours, — is a
structureless basement membrane, of extreme thinness and trans-
parency, the latter being unaffected by water, alcohol or acids; very
brittle, exceedingly elastic, and curls up inwardly upon itself, when
detached from the true cornea. At the corneal margin it breaks up
into fibres, some of which are continuous with the ligamentum
pectinatum of the iris.
Fontana' s Spaces (spatia anguli iridis), — are small, cavernous spaces
between the fibres which go to form the ligamentum pectinatum.
In some animals, as the ox, they form regular canals. They com-
municate with the anterior chamber and with the —
X j Canal of Schlemm, or Sinus Venosus Sclerce, — a minute canal at the
internal corneo-sclerotic junction, extending around the circumfer-
ence of the attached border of the iris. It. communicates with the
anterior chamber through the spaces of Fontana, also with the scleral
v veins.
Posterior Endothelial Layer (endothelium cameras anterioris), — a single
layer of flattened, polygonal, transparent, nucleated cells, covers
the posterior surface of the elastic lamina, lines the anterior chamber
and the spaces of Fontana, and is reflected on to the front of the iris.
THE EYE 283
Vessels, — none, the capillary vessels terminating in loops at its circum-
ference, so that it is practically a non-vascular structure.
^ j Nerves,— are numerous; 24 to 36 twigs from the Ciliary nerves form an
intricate plexus throughout its laminated substance.
THE CHOROID, CILIARY BODY AND IRIS
The Middle Tunic (Tunica Vasculosa Oculi) of the Eye is formed from
behind forward by the Choroid, the Ciliary Body and the Iris; the former
being the vascular ami pigmented tunic; the latter a circular, muscular
curtain or septum, with the pupil, an opening in its centre; while the ciliary
body connects the choroid with the iris.
The Choroid is a thin, vascular membrane, of dark-brown or chocolate
color, which invests the posterior ^ of the globe, extending from the
optic nerve entrance behind to the ora serrata of the retina. It is loosely
connected externally by the lamina fusca to the sclerotic, the space be-
tween being the peri-choroidallymph-space, and is covered by a thin mem-
brane, the lamina superchoroidea, containing spaces between its constituent
lamellae. Internally it is connected with the pigmentary layer of the retina
by the lamina basalis or membrane of Bruch, a very thin, structureless
membrane. The Choroid terminates anteriorly in the ciliary processes
(see below), and is composed of 2 layers, as follows: —
Lamina Vasculosa, the external layer, — consists chiefly of the venae
vorticosae, the larger branches of the short ciliary arteries, and dark
pigment cells.
Lamina Chorio-capillaris or Tunica Ruyschiana, the internal layer, —
consists of a very fine capillary plexus, formed by the short ciliary
vessels.
Tapelum, — is the name applied to the iridescent appearance seen in the
outer and posterior part of the choroid of many animals.
Arteries, — are the short ciliary and recurrent branches from the long
and anterior ciliary arteries.
Veins (2), — unite into 4 or 5 trunks (4), which pass out through the
sclerotic near its equator.
Nerves (3), — are derived from thej^d, $th and sympathetic, through the
long ciliary and the ciliary branches of the ophthalmic ganglion.
The Ciliary Body (corpus ciliare) (5), comprises the orbiculus ciliaris,
(annulus ciliaris), the ciliary processes, and the ciliary muscle. It con-
nects the choroid with the circumference of the iris. The —
Orbiculus Ciliaris (annulus ciliaris), — is a zone about ^ inch wide,
directly continuous with the anterior part of the choroid.
284 HUMAN ANATOMY
Ciliary Processes, — are 60 to 80 folds, formed by the plaiting of the
choroid and its lamina basalis at their anterior margin, and are
received into corresponding folds of the suspensory ligament of the
lens. They form a sort of plaited frill behind the iris, around the
margin of the lens, and are similar in structure to the choroid.
Ciliary Muscle or Muscle of Bowman (m. ciliaris) , — is a ring of un-
striped muscular fibres on the outer surface of the anterior part of
the choroid, and consists of radiating (fibrae meridianales) and cir-
cular fibres (fibrae circulares). The former arise from the corneo-
sclerotic junction and pass backward to the choroid in front of the
PIG. 89.
Nerves
Sclera
retina. The circular fibres are internal to the radiating ones, have a
circular course around the attachment of the iris, and by drawing
on the ciliary processes they relax the suspensory ligament of the
lens, permitting the lens to become more convex by its own elasticity.
It is supplied by the 3d nerve.
The Iris (6) is a perforated contractile curtain, suspended in the aqueous
humor behind the cornea and in front of the lens, and is the anterior
portion of the middle tunic of the eyeball, being continuous with the
ciliary body and the choroid. It is about % inch wide, K o o inch thick, and
is composed of radiating and circular muscular fibres, a fibrous stroma and
pigment cells, covered by a layer of endothelial cells continuous with those
of the posterior elastic lamina of the cornea. The —
THE EYE 285
Pupil (pupilla), — is the central opening in the iris, situated a little to
the nasal side of the centre, diameter >^2 to Y± inch.
Ligamentum Pectinatum Iridis, or Dollinger's band, — is the suspensory
ligament of the iris, connecting its ciliary margin with the posterior
elastic lamina of the cornea.
Pars Iridica Retina or Uvea, — pigmented epithelium of deep purple
color, on the posterior surface of the iris.
Sphincter Pupillce, — a layer of circular muscular fibres around the pupil-
lary margin, supplied by the 3d nerve.
Dilator Pupilla, — radiating muscular fibres from the pupillary margin
toward the ciliary border, supplied by fibres of the sympathetic from
the ciliary ganglion.
Membrana Pupillaris, — a vascular membrane which covers the pupil in
the foetus, disappearing about the eighth month, occasionally perma-
nent.
Arteries, — are derived from the long and anterior ciliary, forming the
circulus major at the ciliary border, and the circulus minor near the
pupillary margin.
Veins, — empty into those of the ciliary processes and the anterior
ciliary veins.
Nerves of the Iris, — are derived from the 3d, 5th and the sympathetic,
through the long and short ciliary nerves. The 3d supplies the
circular fibres, the sympathetic the radiating ones, the 5th being
nerves of common sensation.
THE RETINA (TUNICA INTERNA)
The Retina, the innermost or nervous tunic of the eye, is a delicate,
grayish, transparent membrane, about ^75 of an inch thick at the fundus,
3^oo inch at the anterior margin. It is formed by a membranous ex-
pansion of the optic nerve elements, and extends from the termination of
that nerve nearly as far forward as the ciliary processes, terminating in a
jagged margin, the or a serrata, though its fibrous stroma is continued as
the pars ciliaris retina over the ciliary body. The Retina presents for
examination the following points: —
Macula LiUea, or Yellow Spot, — situated on the retina, exactly in the
visual axis; in an elevated oval spot where vision is very acute, the
retina being very thin and full of nerve elements closely packed
together at the expense of its connective tissue. No rods, no nerve-
fibre layer here, but the cones and ganglion-cells are very numerous.
Fovea Centralis, — a depression at the centre of the macula lutea, M 25
to Ko inch in diameter, in which the sense of vision is most acute.
286 HUMAN ANATOMY
Porus Opticus or Optic Disk, — the point where the optic nerve enters,
lies about % inch internal to the yellow spot. It is often called the
blind spot, being the only part of the fundus from which the power of
vision is absent.
Cotticulus Nervi Optici or Optic Papilla, — is a slight eminence of the
nervous substance at the porus opticus; the central artery of the
retina pierces its centre which is depressed slightly, forming the
Optic Cup (excavatio papillae nervi optici).
Pars Ciliaris Retina, — is that portion of the retinal stroma which is
prolonged over the ciliary body, and continued over the back of the
iris as the pars iridica retina. It is destitute of nerve-elements.
Arteries of the Retina, — arise from the arteria centralis retinas (branch
of the ophthalmic artery), just behind the porus opticus; run chiefly
upward and downward, accompanied by veins, to terminate in a
minute capillary plexus. They do not anastomose with each other,
being terminal arteries. No vessels exist in the fovea centralis, and
only the finest capillaries in the macula lutea.
Structure of the Retina. The retina is composed of nervous elements,
blood-vessels, pigmented epithelium, and modified connective tissue re-
sembling the neuroglia of the brain; the latter being called the radiating
fibres or fibres of Mutter, which form the two limiting membranes and
stretch between them, passing through all the nervous layers except
Jacob's membrane. The structures are arranged in 10 layers, as follows: —
Membrana Limitans Interna, — derived from the supporting frame-work
and shown in the cut by the lowest line.
Layer of Nerve-fibres (stratum opticum) (i), — formed by the expansion
of the optic nerve, the fibres of which, as simple axis-cylinders, pass
through all the succeeding layers of the retina.
Ganglionic Layer (2), — a single layer of large ganglion-cells, which give
off their axons into the preceding layer and their dendrites into the
inner molecular layer.
Inner Plexiform Layer (3), — is made up of a dense reticulum of minute
fibrils, formed by the interlacement of the dendrites of the ganglion-
cells with those of the cells of the next layer.
Inner Nuclear or Granular Layer (4), — consists of closely packed cells of
3 kinds, bipolar, amacrine, and cells connected with the fibres of
Miiller.
Outer Plexiform Layer (5), — a dense network of minute fibrils derived
from the processes of the cells in the adjoining layers.
Outer Nuclear or Granular Layer (6), — contains several strata of oval
nuclear bodies, named rod-granules and cone granules, which are
THE EYE
287
FIG. 90.
respectively continuous with the rods and cones of Jacob's membrane.
Membrana Limitans Externa, — derived from the supporting frame-
work of the retina, is shown in the cut by a horizontal line between
layers 6 and 7.
Jacob's Membrane, or Layer of Rods and Cones (7), — the perceptive
portion of the retina, is composed of a
palisade-like arrangement of rods and
cones, the terminal organs probably
of the optic nerve fibres.
Pigmentary Layer, or Tapetum Nigrum
(8), — formerly described as a part of
the choroid, consists of a single layer
of hexagonal epithelial cells, loaded
with pigment-granules. It extends
with the retinal stroma as the pars
ciliaris retina, (see page 285), beyond
the ora serrata, where the nervous
layers terminate.
REFRACTING MEDIA
The Aqueous Humor (humor aqueus) is
a clear, alkaline, serous fluid, composed of
water 96.7, albumen o.i, chloride of sodium
and extractive matters 3.2, weighing 4 to 5
grains, and filling the anterior (camera oculi
anterior) and posterior aqueous chambers
(camera oculi posterior) which communicate
with each other when the pupil is dilated
sufficiently to remove the pupillary margin
of the iris from the surface of the lens.
The—
Anterior Chamber (camera oculi anterior)
of the Eyeball, — has the cornea in front
and the iris behind. The peripheral
angle of this chamber is called the Fil-
tration Angle (angulus iridis).
Posterior Chamber (camera oculi posterior) of the Eyeball, — is a narrow
chink between the peripheral part of the iris, the suspensory ligament
of the lens, and the ciliary processes.
The Vitreous Body (corpus vitreum) is a transparent jelly-like sub-
stance, composed of an albuminous fluid enclosed in a delicate membrane,
288 HUMAN ANATOMY
also transparent and named the hyaloid membrane (membrana hyaloidea).
It is apparently structureless, has neither vessels nor nerves, and is situated
in the concavity of the retina, which it fills, forming about Y§ of the entire
globe. Running antero-posteriorly in its centre is a canal, filled with fluid,
and lined by a prolongation of the hyaloid membrane, called the —
Canal of Stilling (canalis hyaloideus), — which in the foetus conveyed the
hyaloid artery to the membrana pupillaris. It extends from the
entrance of the optic nerve, forwards directly through the centre
of the vitreous humor to the back of the crystalline lens.
Fossa Patellaris, — is a deep concavity on the front of the vitreous, for
the posterior convex surface of the lens.
Hyaloid Membrane, — is the delicate capsule which encloses the vitreous
humor, and has been supposed to give off delicate septa into its sub-
stance. In front of the ora serrata it is thickened and is termed the —
Zonula Ciliaris or Zonule of Zinn, — presents a series of furrows, radially
arranged, for the reception of the ciliary processes. It splits into 2
layers, one of which lines the fossa patellaris, the other is the —
Suspensory Ligament of the Lens, — passes over the ciliary body to be
attached to the capsule of the lens.
Canal of Petit (spatia zonularia), — a sacculated canal, behind the
suspensory ligament, encircles the equator of the lens, and lies
between the two layers into which the zonule of Zinn is split.
The Crystalline Lens (lens crystallina) is a bi-convex, elastic, trans-
parent body, enclosed in a capsule, held in place by a suspensory ligament,
and situated immediately behind the pupil
and in front of the vitreous body, in the fossa
patellaris of which its posterior and most con-
vex surface rests. The ciliary processes en-
circle it and slightly overlap its margin. It
consists of concentric layers formed of minute
parallel fibres, which are hexagonal prisms with
dentated edges fitting accurately into each
other. Faint lines, six or more in number,
radiate from the anterior and posterior poles
to the circumference and correspond to the free edges of septa in the
lens. The external layers are soft, the deeper are firmer, and the central
ones form a hard nucleus, the nucleus lentis. The lens is unorganized,
having neither vessels nor nerves, but is nourished by imbibition from
neighboring structures, possibly from the aqueous humor. Its —
Capsule (capsula lentis), — is transparent, elastic, iHjooo incn thick
antreiorly, Hooo inch posteriorly; has a layer of flat cells between its
THE EYE 289
anterior portion and the lens, which, after death, break down into a
fluid, the liquor morgagni.
Suspensory Ligament, — connects the capsule with the ciliary body,
and is the anterior of the two layers formed by the splitting of the
zonule of Zinn (zonula ciliaris) (see p. 287). It is shown exaggerated
in the cut.
Canal of Petit, (spatia zonularia), — is a triangular space around the
circumference of the lens, formed by the separation of the two por-
tions of the zonule of Zinn (zonula ciliaris) (shown inflated in the cut).
MUSCLES AND NERVES OF THE EYEBALL
Muscles of the Eyeball, are 6 in number, 4 Recti and 2 Oblique, which
are inserted into the sclerotic coat (tunica fibrosa), just behind the margin
of the cornea. The insertions of the superior, inferior, internal and ex-
ternal recti correspond to the ends of the four
FIG. 92. , ....
arms of an equal-armed cross, imagined to exist
behind the corneo-sclerotic junction. The inser-
tion of the superior oblique (14) lies between the
insertions of the superior and external rect, that
of the inferior oblique (13) somewhat behind the
insertion of the superior oblique. These muscles
are described on page 76. The tendon of the
superior oblique passes through a pulley or trochlea
on the internal angular process of the frontal bone,
before being inserted into the eyeball: (see Fig. 92).
Nerves supplying the muscles of the eyeball are the 3d, 4th and 6th
cranial nerves; the 3d supplies the superior, inferior and internal recti
and the inferior oblique, the 4th supplies the superior oblique, and the
6th supplies the external rectus.
VESSELS OF THE EYE
Arteries supplying the eye and its appendages are, — the Ophthalmic
and Anterior Cerebral branches of the internal carotid artery; and the
Infra-orbital branch of the internal maxillary, from the external carotid.
The Ophthalmic Artery arises from the cavernous portion of the internal
carotid, enters the optic foramen to the orbit, and gives off the following
branches to the eye and its appendages: —
Arteria Centralis Retina (2), — pierces the optic nerve (i) obliquely, and
is distributed to the retina.
Muscular Branches, 2, — superior and inferior, supply the muscles of
the eyeball, and give off the anterior ciliary (see below).
2QO HUMAN ANATOMY
Lacrintal, — to the lacrimal gland, the eyelids, and the conjunctiva,
anastomosing with the palpebral.
Supra-orbital, — supplies the superior rectus and levator palpebrae
muscles.
Internal Palpebral (aa. palpebrales mediales), — superior and inferior,
— to the eyelids.
Nasal, (a. dorsalis nasi), — to the lacrimal sac, and the nose.
Short Ciliary (aa. ciliares posteriores breves), 6 to 12, — pierce the sclerotic
at the lamina cribrosa, supplying the choroid and the ciliary processes.
Long Ciliary (aa. ciliares posteriores longag), 2, — pierce the sclerotic, and
pass forward between it and the choroid, to supply the iris, forming
two arterial circles thereon, the circulus major at the ciliary border,
and the circulus minor near the pupillary margin.
Anterior Ciliary (aa. ciliares anteriores) (3), — arise from the muscular
branches, form a zone beneath the conjunctiva, then pierce the
sclerotic, and join the circulus major on the iris.
Anterior Cerebral, branch of the Internal Carotid, — sends nutrient
capillaries to the optic nerve.
Infra-orbital, branch of the Internal Maxillary artery, — sends branches
to the inferior rectus and inferior oblique muscles, and to the lac-
rimal gland.
Veins of the Eye are collected into two main trunks, the Superior and
Inferior Ophthalmic Veins, which empty into the cavernous sinus, after
collecting the blood from the smaller venous channels through the Vena
Vorticosa of the choroid. The veins of the eye anastomose freely with the
facial veins, thus permitting the escape of venous blood in either direction.
Lymph-spaces of the Eye. The principal lymph-spaces found in the
eyeball and its connected structures are the — •
Canal of Schlemm (sinus venosus sclerae), — around the circumference
of the iris.
Peri-choroidal Space, — between the choroid and the sclerotic (tunica
fibrosa).
Peri-sclerotic Space, — between the sclerotic (tunica fibrosa) and the
capsule of Tenon (fascia bulbi), is continuous with the subdural and
subarachnoid spaces.
Vaginal Spaces, — have been described as existing between the sheaths
of the optic nerve.
NERVES OF THE EYE
Nerves of the Eye. Besides the 3d, 4th and 6th nerves, already men-
tioned as supplying the muscles of the eyeball, the eye is supplied with
THE EYE
291
common sensation by branches from the ophthalmic division of the 5th
and the ophthalmic ganglion, also motor filaments from the 5th, and its
special sense of sight, from the 2d or optic nerve. The —
Sympathetic Branches, — arise from the medulla, and the cavernous
and carotid plexuses, and join the 3d, 4th, 5th, and 6th nerves, send-
ing filaments to the dilator fibres of the iris, to the muscles of the orbit
and lids, to the ophthalmic ganglion, and to the walls of the arteries.
Short Ciliary, — some 6 to 10 in number, arise from the ophthalmic
ganglion (see page 224), pierce the sclerotic and go to the ciliary
muscle, iris, cornea, and to the sheath of the optic nerve.
Ascending, — from Meckel's (spheno-palatine) ganglion (see page 224).
enter the orbit by the spheno-maxillary fissure, going to the 'optic
nerve, the 6th nerve, and the ciliary ganglion.
FIG. 93.
CILIARY GANGLION
The Optic Nerve, 2d Cranial (Plate 6, page 244), begins at the anterior
part of the optic commissure, passes into the orbit by the optic foramen
in company with the ophthalmic artery, is pierced by the central artery
of the retina, and enters the eyeball posteriorly % inch inwardly from its
axis, piercing the sclerotic (tunic fibrosa) and choroid coats, and finally
expanding in the retina. f It is surrounded by a tubular process of dura
mater, which as the nerve enters the orbit, subdivides to form both the
sheath of the nerve and the periosteum of the orbit. The two nerves are
connected together at the commissure, from the back of which most of
their fibres may be traced through the optic tracts to the lower visual centres
2Q2 HUMAN ANATOMY
of the brain, viz. — the external (lateral) geniculate body, the upper
quadrigeminal body, (colliculus superior), and the pulvinar of the optic
thalamus.
The Optic Commissure or Chiasma (Plate 6, page 244), is seen at the
base of the brain in front of the tuber cinereum and behind the lamina
cinerea. It contains four sets of fibres, one of which decussates in the
commissure with its fellow set of the opposite side. The four sets of
fibres are arranged in the following manner: —
Crossed or Decussating Fibres (i), — are the most numerous; lying in the
centre of the commissure, they pass from the optic tract of one side
to the optic nerve of the other side, con-
necting the retina of each eye with the op- FlG*
posite hemisphere of the brain.
Uncrossed or Longitudinal Fibres (2), — occupy
the outer sides of the commissure and
tracts, passing from the tracts to the nerves
of the same sides, and connecting the tem-
poral side of each retina with the cerebral
hemisphere of its own side.
Inter-retinal Fibres (3), — in the anterior portion of the commissure,
pass from one optic nerve to the other, connecting the nasal sides of
the retinas of both eyes with each other.
Commissural Fibres (4) or Commissure of Gudden, — in the posterior por-
tion of the commissure, have nothing to do with vision, but pass from
one internal (medial) geniculate body to the other, or to the op-
posite posterior quadrigeminal body (colliculus inferior) (Whitaker).
The Optic Tract arises from the brain by two bands, an external and an
internal. The external (lateral) band arises from the external (lateral)
geniculate body, the upper quadrigeminal body (colliculus superior) and
the pulvinar of the optic thalamus, the lower visual centres. The internal
(medial) band arises from the internal (medial) geniculate body and the
inferior quadrigeminal body (colliculus inferior), most of its fibres being
commissural between the two internal (medial) geniculates. The two
bands wind around the crus (cerebral peduncle) and join together opposite
its centre in a flattened band, which becomes cylindrical and continues on
to connect with the tract of the opposite side in the optic commissure.
In its course the tract is attached to the surface of the crus by its anterior
margin, and receives some fibres from the tuber cinereum and the lamina
cinerea (lamina terminalis).
Meynert's Commissure (fasciculus retroflexus), — consists of the fibres
THE EYE 293
from the epithalamic habenular nucleus, which cross in the optic
commissure and enter the crus (cerebral peduncle) on the opposite
side, passing obliquely through the red nucleus into the hypothalamic
nucleus. It is concerned with olfactory impulses.
Visual Centres in the Brain. The lower visual centres are the external
(lateral) geniculate body, the upper quadrigeminal body (colliculus
superior), and the pulvinar of the optic thalamus, to which the optic
nerve fibres are traced. From these nuclei other fibres go to the cortical
visual centre, which is located in the cuneus of the occipital lobe, and
probably also in the adjacent lingual lobule of the temporal lobe,
APPENDAGES OF THE EYE
The Tutamina Oculi (organa oculi accessoria) or appendages of the eye,
include the eyebrows, the eyelids, the conjunctiva, the lacrimal gland, the
lacrimal sac, and the nasal duct (ductus naso-lacrimalis).
The Eyebrows, or Supercilia, are two arched eminences of thickened
integument over the supra-orbital arches, and connected beneath with the
orbicularis palpebrarum, corrugator supercilii and occipito-frontalis mus-
cles. They are covered with short, thick hairs, and are drawn downward
and inward by the corrugator supercilii: (see page 75).
The Eyelids, or Palpebrae, are two thin, movable folds, placed in front
of the eye, for its protection. The upper lid is the more movable one,
having its own levator muscle, the levator palpebrae superioris. They are
composed externally of skin, internally of mucous membrane (the palpebral
conjunctiva), and between these lie areolar tissue, the orbicularis muscle,
tarsal cartilage, fibrous membrane, Meibomian glands (glandulae tarsales),
vessels and nerves. The upper lid has, in addition, the aponeurosis of
the levator palpebrae.
Eyelashes, or Cilia, — are a double or triple row of short hairs, situated
on the free margins of the lids; their follicles lying in the connective
tissue beneath the tarsal cartilages.
Glands of Moll (glandulae ciliares), — are enlarged and modified sweat-
glands, the openings of which are in several rows, near the attachment
of the eyelashes.
Palpebral Fissure (rima palpebrarum), — is the space between the free
margin of the lids, its outer and inner angles being termed respect-
ively the external (commissura palpebrarum lateralis) and internal
(commissura palpebrarum medialis) canthus.
Lacus Lacrimalis, — is a small triangular space at the internal canthus,
between the lids and the globe.
294 HUMAN ANATOMY
Lacrimal Papilla, — on the edge of each lid, about 34 inch from the
internal canthus.
Punctum Lacrimale, — a minute orifice on each papilla, and the beginning
of the lacrimal canal.
Tar sal Plates (tarsi), — are two thin, elongated plates of dense connect-
ive tissue, about an inch in length, placed one in each lid, giving it
form and support. The upper one is crescentic in shape, the lower
one is elliptical and smaller.
Tar sal Ligaments, external (ligamentum palpebralis laterale), — con-
nects the outer angle of the tarsal plate to the malar bone. The
internal (ligamentum palpebralis mediale) connects the inner angle
of the plate to the nasal process of the maxilla. The internal one
is often called the tendo oculi.
Meibomian Glands (glandulae tarsales) (i), — are sebaceous glands em-
bedded in grooves in the inner surface of the tarsal plates, about 30
in the upper eyelid, less in the lower
one. Their ducts open on the inner FlG- 95-
edge of the free margin of the lids
by minute foramina, through which
their secretion is furnished to pre-
vent the lids adhering to each
other.
Muscles, — the palpebral portion of the
orbicularis muscle is very thin and
pale; the tensor tarsi compresses
the punctum lacrimale and the
lacrimal sac: (see page 75).
Arteries, — are the palpebral branches of the ophthalmic artery, forming
the superior and inferior tarsal arches, and anastomosing with the
orbital branch of the temporal, the lacrimal, transverse facial, and
angular arteries.
Nerves y — the 3d, facial, and sympathetic to the muscles; the 5th to the
skin and conjunctiva.
The Conjunctiva (Tunica Conjunctiva) is the mucous membrane lining
the inner surface of the eyelids, and reflected over the front of the sclerotic
and cornea. It is continuous with the mucous lining of the Meibomian
glands (glandulae tarsales), lacrimal ducts, lacrimal sac,naso-lacrimal duct,
duct and lacrimal gland. The —
Palpebral Conjunctiva (tunica conjunctiva palpebrarum), — consists of
connective tissue covered by epithelium, is traversed by furrows, and
has papillae, follicular glands, and lymphoid tissue.
THE EYE
295
Ocular Conjunctiva (tunica conjunctiva bulbi), — is very thin and
transparent, loosely attached on the sclerotic, firmly adherent over
the cornea, where it has no vessels in its structure. It has very few
papillae, and no glands.
Palpebral Folds, superior and inferior, — are where the conjunctiva is
reflected over the globe, the fornix conjunctiva lying between them,
and containing mucous glands and trachoma glands, the latter being
analogous to lymphoid follicles.
Plica Semilunaris, or Semi-lunar Fold, — a crescentic fold of conjunctiva
at the inner canthus, considered to be the rudiment of the membrana
nidi tans or 3d eyelid of birds.
Caruncula lacrimalis, — is a small, red, conical body, situated in the
lacus lacrimalis, at the inner canthus of the eye; consisting of a small
island of skin, containing sebaceous and sweat glands, and a few
slender hairs. It is the source of the whitish secretion which collects
at the inner angle of the eye. It is connected by tendinous fibres to
the capsule (fascia bulbi) of Tenon and to the rectusinternus muscle.
The Lacrimal Gland (i) is an oval gland situated in a depression on
the orbital portion of the frontal bone, at the outer angle of the orbit, its
inferior surface resting on the eyeball,
its lower margin or lobe being covered
by conjunctiva. Its front portion is
separated from the rest of the gland
by a fibrous septum, and is called the
accessory gland of Rosenmiillcr (glandula
lacrimalis inferior). Its ducts, from 6
to 12 in number, open by a row of
orifices on the upper and outer por-
tion of the palpebral conjunctiva. Its
secretion, the tears, lubricates the sur-
face of the eyeball; the excess evapo-
rating or being collected in the lacus,
from which it passes through the
puncta (2) into the canaliculi (3) and
the lacrimal sac (4), and thence by the naso-lacrimal duct (5) to the
inferior meatus of the nose.
The Canaliculi (3) or lacrimal canals are two minute canals, ^5 inch
in diameter and Y$ inch long, which extend from the punctum (2) in each
lid to the lacrimal sac (4). They are lined with mucous membrane,
and enveloped by fibres of the tensor tarsi muscle.
FIG. 96.
296 HUMAN ANATOMY
The Lacrimal Sac (4) is the superior dilated extremity of the nasal
duct (5), and is situated in the groove formed by the lacrimal bone and
the nasal process of the maxilla. Its form is oval, flattened antero-
posteriorly; its dimensions about % inch long and % inch wide. Its
fundus is crossed by the tarsal ligament, and by the tensor tarsi muscle.
Its junction with the nasal duct may be interrupted by folds of the lining
mucous membrane.
The Nasal Duct (ductus naso-lacrimalis) (5) is a membranous canal
extending from the lacrimal sac to the inferior meatus of the nose. It is
about % inch long, ^ inch in diameter, is contained in the osseous
lacrimal canal, curving downward, backward and outward, and its
calibre is narrowest about its middle. Its mucous lining is thick, and
continuous with the Schneiderian membrane of the nasal cavity. The —
Valve of Hamer (plica lacrimalis), — is an imperfect valve at the terminal
' orifice (6) of the naso-lacrimal duct, and is formed by a fold of
mucous membrane.
THE EAR (AURIS OR ORGANON AUDITUS)
The Organ of Hearing is divisible into 3 parts — the external ear (auris
externa), the middle ear (auris media) or tympanum, and the internal ear
or labyrinth (auris interna) ; which are situated in or upon the mastoid
and petrous portions of the temporal bone (described on page 20):
The—
External Ear (auris externa), — consists of the auricle or pinna, and
the auditory canal (meatus acusticus externus), which extends to
the membrana tympani.
Middle Ear or Tympanum (auris media), — consists of the atrium or
tympanic cavity proper (cavum tympani), and the attic or epitym-
panic recess; it contains the membrana tympani, the ossicles of the
tympanum (ossicula auditus) and the tympanic orifice of the Eus-
tachian tube (tuba auditiva).
Internal Ear or Labyrinth (auris interna), — consists of the osseous
labyrinth (labyrinthus osseus) and the membranous labyrinth
(labyrinthus membranaceus), the latter being contained within the
former, which comprises the vestibule (vestibulum), the semicircular
canals (canales semicirculares ossei), and the cochlea. The mem-
branous labyrinth (labyrinthus membranaceus) consists of the utricle
(utriculus), the saccule (sacculus), and the membranous semicircular
canals (ductus semicirculares), and contains the terminal filaments
of the auditory nerve (n. acusticus).
THE EAR 297
THE EXTERNAL EAR (AURIS EXTERNA)
The Auricle or Pinna (auricula) is the external irregularly shaped
appendage, fastened to the malar and temporal bones by ligaments. It
consists of a thin plate of yellow fibro-cartilage, deficient in places where
its parts are joined together by fibrous tissue, and is covered by peri-
chondrium and integument, the latter containing sebaceous and sweat
glands, and provided with short, downy hairs. The Auricle presents
several elevations and depressions, which are due to the folding of its
cartilage, and are named as follows: —
Helix, — the outer curved edge of the pinna, beneath which is a deep
groove, the fossa navicularis (scapha) or fossa of the helix.
Anti-helix, — a curved ridge, parallel with and in front of the helix, bifur-
cating above forming the crura antihelicis which enclose a triangular
depression, the fossa triangularis auriculae.
Concha Auricula, — the central cavity leading into the auditory canal
(meatus acusticus externus).
Tragus,-^-& conical eminence in front of the concha, usually covered
with hair along its inferior border.
Anti-tragus, — a smaller projection facing the tragus, from which it is
separated by a deep fissure, the incisura intertragica.
Tubercle (tuberculum auricula} of Darwin, — a small tubercle frequently
seen, where the helix turns downward.
Lobe or Lobule Auricula, — the soft, pendulous portion, composed of
integumentary, adipose and connective tissues.
Muscles of the Auricle. The extrinsic muscles are the Attollens,
Attrahens and Retrahens Auriculam, described on page 75. The intrinsic
muscles are very slightly developed (see page 79) and are the —
/• Musculus Hdicis Major, — vertically on the anterior border of the helix.
^_ Musculus Helicis Minor, — on the lateral surface of the root of the helix.
Musculus Tragicus, — lies vertically on the outer surface of the tragus.
Musculus Anti-tragicus, — on the^posterior wall of the auditory canal.
Musculus Transversus Auricula, — on the posterior surface of the auricle,
radiating outward from the convexity of the concha.
Musculus Obliquus Auricula, — also on the posterior surface, radiating
upward from the convexity of the concha.
The Auditory Canal (meatus acusticus externus) is an osseo-cartilaginous
tube, about i finches long, extending from the concha to the membrana
tympani, and curved irregularly in its course. The cartilaginous, or
external portion, is about ^ inch long, and deficient posteriorly and above,
where it is filled by strong fibrous tissue. The canal is lined with integu-
298 HUMAN ANATOMY
ment, having numerous hair follicles, sebaceous and ceruminous glands.
Its relations are — in front, the condyle of the lower jaw; below and in front,
the parotid gland; behind, the mastoid cells and the lateral sinus,
separated from it by a very thin bony plate; above, the mastoid cells and
the dura mater of the brain, separated from it by a thin osseous plate.
The—
Sulcus Tympanicus, — is a circumferential groove at the bottom of the
canal for the insertion of the membrana tympani. It is interrupted
above by a notch, the incisura Rivinii.
Vessels and Nerves. The Arteries of the auricle are derived from the
external carotid artery, viz. — the anterior and posterior auricular, and the
auricular branch of the occipital. Those of the auditory canal are
branches from the posterior auricular, internal maxillary, and temporal
arteries. The Nerves of the canal are derived from the temporo-auricular
branch of the maxillary division of the 5th, and the auricular branch of the
Vagus. Those of the auricle are the —
Auricularis Magnus, — from the cervical plexus.
Auricular, — branch of the vagus (also called Arnold's nerve).
Auriculo-iemporal, branch of the mandibular div. of the 5th.
Occipitalis Major, — from the post, division of the 2nd cervical nerve.
Occipitalis Minor,' — from the cervical plexus.
Posterior Auricular, — branch of the facial, to the muscles.
THE MEMBRANA TYMPANI
The Membrana Tympani, or Drumhead, is an oval, inelastic, semi-
transparent membrane, about ^50 inch in thickness, situated obliquely
at the bottom of the auditory canal, inclined inward and forward, so as to
form almost a continuation of the posterior wall of the canal. As seen
through the canal, it is of a delicate blue-gray color, arched inward, and
presents for consideration the following points: —
Malleolar Eminence, — white in color at the upper border, made by the
short process of the malleus behind.
Malleolar Stripe, — also white, running downward from the eminence and
formed by the handle of the malleus behind.
Light-spot, — a triangular reflection, its apex at the tip of the malleus
handle, its base extending to the periphery of the membrane. It is
due to the concavity of the exterior surface of the membrane.
Umbo, or Navel, — is the dark, central, depressed part of the membrane.
ShrapnelVs Membrane (pars flaccida), — is the upper posterior part of
the drumhead, where it is somewhat flaccid.
THE EAR
2Q9
Structure. The Membrana Tympani is composed of 3 layers, an ex-
ternal or cuticular layer (stratum cutaneum), a middle or fibrous (mem-
brana propria), and an internal or mucous layer (stratum mucosum).
Its circumference is thickened to form an incomplete ring (annulus
fibrocartilagineus), which is received into the sulcus tympanicus at the
inner end of the auditory canal. The anterior and
posterior ends of this ring are shown by (z>) and (h)
in the figure. The —
External or Cuticular Layer (stratum cutaneum), —
is derived from the integument lining the audi-
tory canal (meatus acusticus externus).
Middle or Fibrous Layer (membrana propria), —
consists of an outer layer of fibres which radiate
from the handle of the malleus; and an inner
layer of circular fibres, most numerous around the circumference.
Between these two sets of fibres are situated the short process and
handle of the malleus.
Internal or Mucous Layer (stratum mucosum), — is continuous with the
mucous lining of the tympanum.
The Internal Surface of the Membrana Tympani is convex, and presents
the curved handle of the malleus pointing downward between its layers,
also the chorda tympani nerve passing along the upper margin to the iter
chordae anterius in the Glaserian (tympano-squamous) fissure.
Nerves and Vessels. The Membrana Tympani receives its nervous
supply from the auriculo-temporal branch of the mandibular, the auricular
branch of the vagus and the tympanic branch of the glosso-pharyngeal.
The Veins open into the external jugular, except those on the inner surface,
which drain partly into the lateral sinus and veins of the dura mater, and
partly into a plexus on the Eustachian tube (tuba auditiva). The
Arteries are the —
Deep A uricular, branch of the internal maxillary, — supplies the external
layer, and forms with the tympanic branches a capillary plexus in the
middle layer.
Tympanic Branches, of the internal maxillary and internal carotid arte-
ries,— supply the internal layer, the former with the stylo-mastoid
artery forming a vascular circle around the membrane, and both
anastomosing on the membrane with the —
Vidian (a. canalis pterygoidea), — branch of the internal maxillary, and
the—
Stylo-mastoid, — from the posterior auricular branch of the external
carotid.
3OO HUMAN ANATOMY
THE MIDDLE EAR OR TYMPANUM (AURIS MEDIA)
The Tympanum, or Drum (auris media), is an irregular cavity within
the petrous portion of the temporal bone, lying between the membrana
tympani and the tympanic surface of the petrous bone and communicating
with the naso-pharynx by the Eustachian tube (tuba auditiva). It
contains the ossicles (ossicula auditus) of the tympanum, part of the
chorda tympani nerve, and air. Its average diameters are about % inch
antero-posteriorly, ^ to % inch vertically, and 3-f 2 to ^ inch transversely.
It consists of two parts, the atrium or tympanic cavity proper (cavum
tympani), opposite the tympanic membrane; and the-fl&ix; or epitympanic
recess above, containing the upper half of the malleus and the greater part
of the incus. Its roof and floor are formed by thin osseous laminae, the
floor separating it from the jugular fossa and vein, and presenting, near
the inner wall, a small aperture for, Jacol 'son's nerve (tympanic branch of
the glosso-pharyngeal). The other walls cf the tympanum present for
examination the following points: —
OUTER WALL (paries membranacea), — is formed by the membrana
tympani and presents the —
Her Chorda Posterius, — opens close to the posterior edge of the drum-
head, for the passage of the chorda tympani nerve.
Her Chorda Anterius (canal of Huguier), — opens just in front of the
drumhead, for the passage of the chorda tympani nerve.
Glaserian (tympano-squamous) Fissure, — opens above and in front of
the drumhead, receiving the long process (processus gracilis or
anterior) of the malleus, the anterior ligament of the malleus, (laxator
tympani tendon) and the tympanic branch of the internal maxillary
artery.
INNER WALL (paries labyrinthica), — is the outer wall of the labyrinth,
presents the —
Fenestra Vestibuli or Ovalis, — an oval opening, leading into the vestibule,
and closed by a membrane, to which is attached the base of the stapes.
Fenestra Cochlea or Rotunda, — a smaller opening, below the fenestra
vestibuli, leading into the scala tympani of the cochlea, and closed by
the membrana tympani secundaria, a membrane of 3 layers.
Promontory, — an elevation corresponding to the first turn of the cochlea,
situated between the fenestras and in front of them. It is grooved by
the tympanic plexus.
Ridge of the Aquceductus Fallopii (prominentia canalis facialis), — above
the fenestra vestibuli, behind which it curves downward along the
posterior wall.
POSTERIOR WALL (paries mastoidea), separates it from the mastoid cells,
and presents the —
THE EAR 301
Opening of the Tympanic or Mastoid Antrum, — which in turn com-
municates with the mastoid cells.
Pyramid (eminentia pyramidalis), — a hollow conical eminence, behind
the fenestra vestibuli, contains the stapedius muscle, and a minute
canal communicating with the aquaeductus Fallopii (canalis facialis)
and transmitting a nerve to the stapedius.
ANTERIOR WALL (paries carotica), separates it from the carotid canal,
and presents the —
Opening of Canal (semicanalis m. tensoris tympani) for the Tensor
Tympani Muscle, — above, situated on a small projection, sometimes
called the anterior pyramid.
Opening of the Eusiachian Tube (semicanalis tubae auditivae), — next
below, the two canals being separated from each other by a thin,
horizontal, bony plate, the processus cochleariformis (septum canalis
musculotubarii) .
The Ossicles (ossicula auditus) of the Tympanum are three small bones,
which form a chain across the tympanic cavity, connecting the mem-
brana tympani with the fenestra vestibuli, and named the — •
Malleus, or Hammer (A), — consists of a head, neck, short process
(processus lateralis), long process or processus gracilis (processus
anterior), and handle or manubrium. The
short process and handle are fastened to the
middle layer of the drumhead. The long
process (never found in adults) is received
into the Glaserian (tympano-squamous)
fissure, and the head articulates with the
head of the incus.
Incus, or Anvil (B), — resembles a two-pronged
tooth; it has a head, also a long and a short
process. The head articulates with the head
of the malleus, the short process with the fossa incudis in the epitym-
panic recess, the long process with the head of the stapes, by the
os orbictdare, its convex extremity.
Stapej,.or Stirrup (C), — presents a head, neck, base and two crura. Its
head articulates with the incus, its base rests on the membrane clos-
ing the fenestra vestibuli, its neck receives the tendon of the stapedius
muscle.
Ligaments of the Ossicles are 5 in number, besides the capsular
ligaments of their articulations, 3 for the malleus, i for the incus, and i
for the stapes, as follows: —
3O2 HUMAN ANATOMY
Anterior Ligament of the Malleus, — is the degenerated laxator tympani
muscle, from the neck of the malleus through the tympano-squamous
fissure or its petro-tympanic subdivision to the base of the alar
spine of the sphenoid. It is an active muscle in most infants and
about 75 per cent, of adults.
Superior of the Malleus, — from the head of the malleus to the roof of the
epitympanic recess.
External of the Malleus, — from the short process of the malleus to the
posterior part of the notch in the tympanic ring.
Posterior of the Incus, — from the end of the short process of the incus
to the posterior part of the epitympanic recess. [The so-called supe-
rior ligament of the incus is merely a fold of mucous membrane.]
Annular Ligament of tfte Stapes (ligamentum annulare baseos stapedis),
— around the circumference of the base of the stapes, connecting it
to the margin of the fenestra vestibuli.
Muscles of the Tympanum are 2, the Tensor Tympani Stapedius
and the laxator tympani.
Tensor Tympani, — arises from the under surface of the petrous portion
of the temporal bone, the cartilaginous Eustachian tube (pars car-
tilaginea tubae auditivae), and its own osseous canal (semicanalis
m. tensoris tympani); and is inserted into the handle of the malleus.
It draws the membrana tympani inward and tense. Its nerve is a
branch from the trigeminal, through the otic ganglion.
Stapedius, — arises from a conical cavity in the interior of the pyramid;
its tendon emerges from the orifice at the apex of the pyramid, and
is inserted into the neck of the stapes. It draws the head of the stapes
backward, and probably compresses the contents of the vestibule.
Its nerve is the tympanic branch of the facial.
Laxator Tympani, — see anterior ligament of malleus (see page 80).
Vessels of the Tympanum. The Veins terminate in the pterygoid
plexus and in the superior petrosal sinus. The Arteries are 6 in number,
as follows: —
Tympanic, — branch of the internal maxillary, entering by the petro
tympanic fissure, anastomosing on the membrana tympani, in a
vascular circle with the Stylo-mastoid and Vidian arteries, and the
Tympanic br. of the internal carotid.
Stylo-mastoid, — br. of the posterior auricular br. of the external carotid
entering at the stylo-mastoid foramen.
Petrosal; — br. of middle meningeal artery, entering by the hiatus Fallopii.
Tympanic, — br. from the internal carotid artery.
THE EAR 303
Branch from tJie Ascending Pharyngeal,-^irom the external carotid; also
accompanying the Eustachian tube.
Nerves of the Tympanum. Besides the nerves supplying the two
muscles (see above), the Chorda Tympani Nerve enters the tympanum
by the iter chordae posterius, crosses the cavity between the handle
of the malleus and the long process of the incus, and makes its exit
by the iter chordae anterius, after passing close along the upper part
of the membrana tympani. The mucous membrane lining the
tympanum is supplied by the branches of distribution of the Tympanic
Plexus, which lies on the inner wall around the promontory, and is
formed by the —
Tympanic Branch of the Glosso-pharyngeal, — also known as Jacobson's
nerve, enters by an aperture in the floor near the inner wall.
Small Deep Petrosal, — from the carotid plexus of the sympathetic, enters
from the carotid canal.
Small Superficial Pelrosal, — from the otic ganglion, enters near the canal
for the tensor tympani muscle.
Branch from the Great Superficial Pelrosal, — enters through the inner
wall, just in front of the fenestra vestibuli.
The Eustachian or Auditory Tube (tuba auditiva) is an osseo-car-
tilaginous canal, about i% inches long, ^2 to ^3 inch in diameter, which
forms a channel of communication between the tympanum and the pharynx.
It passes obliquely downward, forward and inward, from the anterior
wall of the tympanum to the naso-pharynx, where it ends in an oval orifice
on the side wall of the pharynx just behind the inferior meatus of the nose.
The osseous part (pars ossea tubae auditivae), ^ inch long, terminates
at the retiring angle of junction of the petrous and squamous portions
of the temporal bone, in a jagged margin, to which the cartilaginous part
(pars cartilaginea tubae auditivae) is attached. The latter, i inch long,
is formed by a triangular plate of elastic fibro-cartilage, folded on itself
above so as to leave a deficiency below, which is filled by fibrous tissue.
This portion of the tube expands as it descends into a trumpet-shaped
lower extremity. The tube is lined by ciliated mucous membrane, con-
tinuous with that of the tympanum and pharynx, and containing mucous
glands, also adenoid tissue near its lower end. The —
Tube-tonsil of Gerlach, — is formed by the adenoid tissue in the mucous
lining near the pharyngeal orifice.
Isthmus, — is the narrowest part of the tube, at the junction of the
osseous and cartilaginous portions.
Muscles, — are the dilator tubae fibres of the tensor palati (m. tensor
304 HUMAN ANATOMY
veli palatini), which open the tube during deglutition, aided by the
salpingo-pharyngeus when present. The levator palati closes the
pharyngeal orifice. For these muscles see page 80.
Arteries, — are the ascending pharyngeal, from the external carotid,
and the Vidian (a. canalis pterygoidea) from the internal maxillary.
Nerves, — are pharyngeal branches from the glosso-pharyngeal, pneumo-
gastric and sympathetic, through the pharyngeal plexus, also the
upper posterior nasal branches of Meckel's (spheno-palatine) ganglion.
The otic ganglion lies on the outer side of the cartilaginous portion
of the tube (pars cartilaginea tubae auditivae), and supplies the
tensor palati muscle (m. tensor veli palatini).
THE INTERNAL EAR OR LABYRINTH (AURIS INTERNA)
The Internal Ear or Labyrinth is the essential part of the organ of
hearing. It lies internal to the tympanum, within the petrous portion of
the temporal bone, and consists of a series of osseous chambers, the
Osseous Labyrinth, containing a fluid, the perilymph, in which lies a mem-
branous reproduction of the chambers, the Membranous Labyrinth, which
also contains a fluid, the endolymph. Within the membranous labyrinth
are distributed the terminal filaments of the auditory nerve, which being
suspended between two fluids, are not only protected from injury, but
enabled to receive the most delicate vibrations communicated to the fluids
surrounding them. The Internal Ear comprises the following-named
structures: —
f Vestibule (4), the central cavity.
Osseous Labyrinth { Semicircular Canals, behind the vestibule.
[ Cochlea (8), in front of the vestibule.
Utricle, a membranous sac, in the recessus
ellipticus of the vestibule.
I Membranous Semicircular Canals (ductus
semicirculares), in the osseous canals.
Membranous Labyrinth. \ _ .
Saccule, a membranous sac, in the recessus
sphaericus of the vestibule.
Membranous Cochlea (ductus cochlearis), a
spiral tube, enclosed in the osseous cochlea.
Auditory Nerve (n. acusticus), — the 8th cranial nerve, Portio Mollis
of the yth pair.
Organ of Corti (organon spirale), — the terminal auditory apparatus, in
the membranous cochlea (ductus cochlearis).
THE EAR 305
Internal Auditory Meatus (meatus acusticus interims), — by which the
auditory nerve enters from the brain.
The Vestibule (4) is the central common cavity of communication be-
tween the osseous parts of the internal ear, and measures in vertical diam-
eter about 3-15 inch, laterally about ^fo inch. It is situated internal to the
tympanum, behind the cochlea (8), and in
front of the semicircular canals (2), communi-
cating in front with the scala vestibuli of the
cochlea, and behind by five openings with the
semicircular canals. It contains a fluid, the
perilymph, also the utricle and saccule of the
membranous labyrinth, and presents the fal-
lowing points: —
Fenestra Vestibuli (fenestra ovalis), — on ils
outer wall, closed by the base of the
stapes and its annular ligament.
Recessus Sphcericus (fovea hemisphaerica)
(7), — a small circular depression on the inner wall, for the saccule,
medially, it presents a small area, macula cribrosa media, which is
perforated by 12 to 15 minute orifices for filaments of the acoustic
nerve.
Crista Vestibuli, — a vertical ridge on the inner wall behind the recessus
sphaericus. It bifurcates below to enclose the —
Recessus Cochlearis, — a small depression, perforated for the passage of
about 8 filaments of the acoustic nerve.
Aquceductus Vestibuli, — opens behind the crista, ending on the posterior
surface of the petrous portion of the temporal bone. It transmits a
small vein, and contains the ductus endo-lymphaticus, a tubular pro-
longation of the lining membrane of the vestibule, which ends in a
cul-de-sac between the layers of the dura mater in the cranial cavity.
Recessus Ellipticus or Fovea Semi-elli plica (6), — a transverse oval de-
pression on the roof for the utricle; behind it are the 5 orifices of
the semicircular canals, and in front is the opening into the scala
vestibuli of the cochlea.
The Semicircular Canals (canales semicirculares ossei) are three C-
shaped bony tubes, each about >^o inch in diameter, situated above and
behind the vestibule, into which they open by 5 apertures. Each canal
lies at a right angle with the other two. The external (lateral) canals of
both ears are virtually in the same plane, while the superior canal of one
ear is in a plane parallel to that of the posterior canal of the other ear
306 HUMAN ANATOMY
(Crum Brown). The superior and posterior canals are each nearly an
inch long, and are placed vertically; they join together behind in the crus
commune, which opens into the vestibule. The external canal is about ^o
inch long, placed horizontally, its arch being directed outward and back-
ward. The canals contain the perilymph, and the membranous semicircu-
lar canals. The —
Ampulla, — is a flask-shaped dilatation of each canal at one extremity,
having a diameter of about Ko inch.
The Cochlea is a spiral canal situated in the eburnated (ivory-like)
portion of the petrous bone, diametrically opposite to the internal auditory
canal (meatus acusticus internus). The depth at which it lies from the
cerebral surface of the bone varies, in different individuals, from ^4 to
of an inch. The promontory in
the tympanum is the only part of the
cochlea that is exposed, elsewhere it is
completely imbedded in solid bone. It
is about iM inches long, tapering from
Ho to J^o inch in diameter, coiled
around a central conical axis for 2%
turns. By removal of surrounding
bone, in conformity with its interior,
the cochlea can be made to resemble a snail-shell in appearance with
its apex pointing forward and outward. Its first turn is separated from
the carotid canal in front by a thin wall. Its central axis, the modiolus,
is of conical shape, and is channeled by small canals for the passage of
arteries and nerves, and by a central one, the^canalis centralis modioli.
Its apex is the last coil of the cochlea, and is expanded into a funnel-
shaped lamella, iheJHfrmdibidum. The —
Canalis Spiralis Modioli, or Spiral Canal, — is the space between the
modiolus and the outer wall of the cochlea. It makes 2 ;34 turns; from
left to right in the right ear, from right to left in the left ear, or in other
words, that of the right ear corresponds to a " right hand " screw; and
terminates in the cupola, a cul-de-sac at the apex of the cochlea.
It presents 3 openings, — the fenestra cochlea (fenestra rotunda),
communicating with the tympanum; the opening into the vestibule,
and the orifice of the aquaeductus cochleae (see below).
Lamina .Spiralis (6), — is a thin, osseous plate, projecting from the
modiolus half way across the spiral canal, and winding around the
modiolus terminates near the apex in a hook-like process, the Jtajnidus^
Its deficiency in the last half turn of the cochlea forms the Helicotrema.
a space in which the two scalae unite. It consists of two laminae,
THE 'EAR 307
between which pass the filaments of the cochlear nerve. From its
free edge the structures composing the membranous cochlea pass to
their attachment on the opposite wall of the cavity. It partially
divides the spiral canal into 2 passages, the scala vestibuli above and
the scala tympani below.
Aquceductus Cochlea, — is a minute funnel-shaped canal which begins
by a small orifice in the lower wall of the scala tympani near the
promontory, and runs in the inner wall of the jugular fossa, ending in
the small deep triangular depression on the posterior border of the
basilar surface of the petrous portion of the temporal bone. It
transmits a vein from the cochlea to the jugular vein, or to the inferior
petrosal sinus, and forms a communication between the perilymph
in the scala tympani and the subarachnoidean space of the brain.
The Membranous Labyrinth (labyrinthus membranaceus) is situated
within the osseous labyrinth, and consists of two membranous sacs, the
Utricle (utriculus) (i) and Saccule (sacculus) (2), together with the Mem-
branous Semicircular Canals (ductus
FlG- IOI> semicirculares) (6), and the Membranous
Cochlea (ductus cochlearis) (5). The
utricle and saccule communicate with
each other indirectly by a small canal
contained in the aquaeductus vestibuli.
The saccule communicates with the
membranous cochlea by the canalis
reuniens of Hensen (4), and the mem-
Acastof^fUabyrmthasseen ^^ ^^^ canals Qpen into
the utricle; so that the membranous
labyrinth affords an uninterrupted channel for the endolymph which it
contains. The walls consist of 3 layers, — an outer fibrous coat, a middle
one resembling the hyaloid membrane, and an inner layer, formed of
polygonal, nucleated epithelial cells. In the walls of the utricle and
saccule are contained 2 small gelatinoid bodies, the Macula Acusticce
which contain flask-shaped Hair Cells and
Otoliths (otoconia), — minute crystals of calcium carbonate, held ta
gether in a mesh of delicate fibrous tissue in which ramify many
minute fibres of the acoustic nerve.
The Utricle (utriculus) (i) is a flattened, oblong membranous sac,
fastened to the inner wall of the vestibule in the fovea semi-elliptica
(recessus ellipticus). It is filled with endolymph, nearly surrounded by
perilymph, and communicates with the saccule through the small tube in
308 HUMAN ANATOMY
the aquaeductus vestibuli. The membranous semicircular canals open
into its cavity behind by 5 orifices. The —
Macula Acustica Utricularis, — is a thickened spot in the wall where it is
lodged in the fovea (recessus), receiving the utricular filaments of the
acoustic nerve.
Ductus Utriculosaccularis, — is given off from the medial wall; it is
joined by a similar duct coming from the saccule; together they form
the Ductus Endolymphaticus which passes through the aquaeductus
vestibuli.
The Saccule (sacculus) (2) is the smaller of the two membranous sacs,
about Hs inch in diameter, attached at one point to the utricle, and also
to the fovea hemispherica (recessus sphaericus) of the vestibule, being else-
where surrounded by perilymph, and containing endolymph. It com-
municates with the utricle through the ductus endolymphaticus in the
aquaeductus vestibuli, and also with the membranous cochlea by the —
Canalis Reuniens of Hens en (4), — about ^5 inch long and K 20 inch in
diameter,- connects the cavity of the saccule and the vestibular end
of the membranous cochlea (ductus cochlearis) (3).
Macida Acustica Saccularis, — is a circular area, ^2 inch in diameter,
on the wall of the saccule, where the saccular filaments of the acoustic
nerve originate.
FIG. 102.
The Membranous Semicircular Canals (ductus semicirculares) have
the same shape as the osseous ones in which they are contained but are
Yz their diameter. They are fastened thereto by the convex curves, and
are elsewhere surrounded by perilymph, except at the ampullary enlarge-
THE EAR 309
ments, where they fill the osseous canals and present a thickened fiddle-
shaped elevation projecting into the cavity and called the septum trans-
versum, in which the nerves end. They are held in position by numerous
fibrous bands, connecting them to the walls of the osseous canals. They
constitute the Organ of Orientation and Equilibration.
The Membranous Cochlea, also called the Ductus Cochlearis or Scala
Media, is a spiral tube enclosed in the spiral canal of the osseous cochlea
(16), lying along its outer wall, to which it is attached, being also attached
to the lamina spiralis (10) on the opposite side of the cavity. It is formed
by the membrana or lamina basilaris (8) below, the vestibular membrane
of Reissner (18) above, and the periosteum of the cochlear wall on the outer
side, its cross-section being of triangular form. It is filled with endolymph,
and contains the organ of Corti (organon spirale) (n) overhung by the
membrana tectoria (7). The —
Limbus Lamina Spiralis (10), — is the soft structure of periosteum on
the edge of the lamina spiralis, and lies in the membranous cochlea.
It has two lips, — an upper, the labium vestibulare, and a lower, the
labium tympanicum, with a C-shaped concavity, the sulcus spiralis
internus, between them.
Vestibular Membrane of Reissner (18), — extends from the edge of the
lamina spiralis to the outer cochlear wall, separating the membranous
cochlea from the scala vestibuli (2).
Membrana or Lamina Basilaris (8), — is the tympanic- wall of the mem-
branous cochlea, extending from the labium tympanicum of the
lamina spiralis to the outer cochlear wall, where its insertion is
called the ligamentum spirale (5), or muscle of Todd and Bowman.
On it rests the Spiral Organ of Corti (n), — covered by the mem-
brana tectoria.
Membrana Tectoria (7), — extends parallel to the membrana or lamina
basilaris from the 'abium vestibulare, over the spiral organ of Corti,
to be attached externally to the outer row of Deiters' cells (see below).
Vas Spirale (9), — a vessel in the vascular connective tissue of the mem-
brana or lamina basilaris, below the spiral organ of Corti.
Zona Arctuala, — is the inner area, and the zona pectinata is the outer
area, of the membrana or lamina basilaris.
The Organ of Corti (organon spirale) (n),or Papilla Spiralis, is situated
on the inner surface of the membrana or lamina basilaris (8), is overlapped
by the free edge of the membrana tectoria (7), and appears as a papilla
winding spirally throughout the length of the membranous cochlea.
It is an arrangement of cells, some of which are rod-like in form, and others
310 HUMAN ANATOMY
are epithelial hair-cells, the whole being supposed to be the essential organ
of hearing. The —
Rods of Corti, — are arranged in two rows, resting, by their pedestals,
on the lamina basilaris, and uniting with each other by their heads,
so as to form an arched tunnel, the tunnel of Corti, between them and
the membrana basilaris all along the length of the cochlea. Number
of rods in inner row about 6,000, in outer row 4,000. Average di-
ameter of the rods, from Msooo to Hsooo inch.
Head-plates, — are attached to the heads of the inner rods, for the recep-
tion of the rods of the opposite row.
FIG. 103.
Lamina Reticularis (i), — a delicate perforated membrane which extends
from the articulations of the rods outward to the external row of
the outer hair-cells.
Auditory Cells (2), — are epithelial structures covering the inner surfaces
of the walls and the floor of the membranous cochlea. Those which
cover the inner rods by a single row number about 3,500, are nucleated,
covered with tufts of cilia, and called the inner hair-cells. On the
outer rods are 3 or 4 rows of similar cells, numbering about 12,000,
and named the outer hair-cells. Between the latter are rows of sup-
porting cells, called the cells of Deiters, and outside them are 5 or 6
rows of columnar cells, the cells of Hensen, beyond which are the cells
of Claudius, covering the outer part of the zona pectinata of the
membrana or lamina basilaris.
The Auditory Nerve (n. acusticus), the 8th or Portio Mollis of the ;th
pair, arises by two roots from the same groove in the medulla as does the
facial nerve which is in front and separated from it by the pars intermedia,
or glosso-palatine nerve (n. intermedius), the medial or vestibular root from
the area acustica or trigonum acusticum in the floor of the 4th ventricle,
the lateral or cochlear root from the accessory nucleus and the tuberculum
acusticum, in the medulla, close to the restiform body. It emerges from
the medulla at the lower border of the pons Varolii, in company with the
facial nerve, from which it receives one or two filaments, both nerves
THE EAR 311
passing into the internal auditory meatus, at the bottom of which the
auditory divides into two branches, vestibular and cochlear. The —
Vestibular Nerve, — has a ganglion, the vestibular ganglion of Scarpa,
on it in the internal auditory meatus; it then divides into 3 branches,
which pass through minute orifices in the bottom of the meatus, and
entering the vestibule, are distributed to the utricle and the ampullae
of the external and superior semicircular canals respectively. This
nerve has nothing to do with hearing, it is purely a nerve of orientation
and equilibration.
Cochlear Nerve, — is the true nerve of hearing, it gives off branches to the
saccule and the ampulla of the posterior semicircular canal, and then
divides at the base of the modiolus of the cochlea into numerous
filaments (14), which pass through the little foramena in the tractus
spiralis foramenosus at the bottom of the internal acoustic meatus,
then between the lamellae of the lamina spiralis, and through the
central canal of the modiolus, to the hair-cells of the spiral organ
of Corti (Fig. 101). On it in the spiral canal of the modiolus is
the—
Ganglion S pirate (13), — consisting of bipolar nerve-cells, which are the
true cells of origin of this nerve, one pole being prolonged centrally
to the brain, and the other peripherally to the hair-cells of Corti's
spiral organ (see lateral lemniscus, page 199).
The Internal Auditory Meatus (meatus acusticus internus) is a large
orifice on the cerebellar surface of the petrous portion of the temporal
bone, leading into a short canal, which runs outward for % inch, and is
closed by a vertical plate, thefundus or lamina cribrosa, divided by a crest,
the crista falciformis (crista transversa), into 4 depressions, which are
perforated by foramina for the passage of the branches of the auditory
nerve into the labyrinth. The —
Tractus Spiralis Foraminosus, — is the anterior lower depression; has a
number of foramina spirally arranged and opening into the central
canal of the cochlea, transmitting the nerves to the cochlea.
Area Cribrosa Media (area vestibularis inferior), — just below the
posterior part of the crest, transmits the nerves to the saccule.
Foramen Singulare, — behind the preceding area, for the nerve to the
posterior semicircular canal.
Area Cribrosa Superior (area vestibularis superior), — above the crest
posteriorly, for the filaments to the utricle and the superior and
external semicircular canals.
Opening of the Aquaductus Fallopii (area n. facialis) above and in front,
for the passage of the facial nerve.
HUMAN ANATOMY
Vessels of the Internal Ear. The Veins accompany the arteries, and
uniting at the base of the modiolus empty into the superior petrosal sinus
or into the lateral sinus. The Arteries are the —
Internal Auditory, br. of the basilar (from the vertebral), — accompanies
the acoustic nerve into the internal auditory meatus, where it divides
into vestibular and cochlear branches.
Stylo-mastoid, br. of the posterior auricular (from the external carotid),
— sends some small branches to the cochlea.
ORGANS OF DIGESTION (APPARATUS
DIGESTORIUS)
The Alimentary Canal is a musculo-membranous tube, about 30 feet
in length, extending from the mouth to the anus, lined throughout with
mucous membrane, furnished with several accessory organs, and perform-
ing the functions of ingestion, mastication, insalivation, deglutition,
digestion, assimilation, and egestion. Its subdivisions are named the —
Mouth, Pharynx, (Esophagus, Stomach, Small Intestine (duodenum,
jejunum and ileum) and Large Intestine (caecum, colon and rectum).
The first three lie above the diaphragm, the rest below it. The portion
from the pharynx down is the "tubus digestorius."
Accessory Organs of Digestion are the — Teeth, Salivary glands (pa-
rotid, sub-mandibular, sub-lingual), Liver, and Pancreas.
THE MOUTH (CAVUM ORIS)
The Mouth is an oval-shaped cavity, placed at the commencement of
the alimentary canal, and consists of the vestibule, and the cavity proper.
The vestibule (vestibulum oris) is a slit-like aperture between the lips and
cheeks externally and the gums and teeth internally. It is partially
interrupted in front in the mid-line by ihejrenula which attach the lips
to the gums, the frenulum of the upper lip being the more developed of the
two. The cavity proper (cavum oris proprium) extends from the alveolar
arches and their teeth in front and laterally to the isthmus of the fauces
behind, by which constricted aperture it communicates with the pharynx.
Its roof is formed by the palate, its floor by the tongue and its mucous
membrane reflected to the lower gum. The lips (labia oris) are the two
fleshy folds, which surround the orifice (rima oris) of the mouth, the cheeks
(buccae) forming its sides and being continuous with the lips in front; both
are formed of skin externally, and mucous membrane internally; between
which are muscle, fat, areolar- tissue, vessels, nerves and glands. The
THE PALATE 313
mouth presents for examination the tongue (see page 272), the gums and
teeth (described separately), the palate, fauces, tonsils, and openings of
ducts from the salivary glands. Special anatomical features presented
by the mouth are the —
Hamular Process of the Medial Pterygoid Lamina of the Sphenoid Bone, —
may be felt behind the last upper molar tooth; also the internal ptery-
goid plate (medial pterygoid lamina), and part of the pterygoid fossa.
Coronoid Process, — of the lower jaw, at its anterior border.
Posterior Palatine Artery, — at the inner side of the last upper molar
tooth, and in front of the hamular process.
Pterygo-mandibular Ligament, — is felt as a fold posteriorly to the last
lower molar tooth.
Lingual Branch of the $th, — the gustatory nerve, — passes over the inner
side of the ramus of the lower jaw, close to the last lower molar tooth.
Openings of Stenson's Ducts, from the parotid glands, — in the vestibule,
one on each cheek, opposite the 2nd upper molar tooth.
Openings of Wharton's Ducts, from the submandibular or submaxillary
glands, — in the cavity proper, one on each side of the f raenum (frenu-
lum linguae) of the tongue.
Openings of the Ducts of Rivinus, from the sublingual glands, — 8 to 20
on each side, open into the cavity proper, on either side of the fraenum
(freiiulum linguae) of tbe tongue.
THE PALATE (PALATUM) AND TONSILS (TONSILL.E "PALATINE)
The Palate forms the roof of the mouth, and consists of the hard palate
(palatum durum) in front, and the soft palate (palatum molle) behind.
The Hard Palate (palatum durum) is formed by the palate process of the
maxilla and the horizontal plate of the palate bone, is covered with
mucous membrane, which is closely adherent to the periosteum, and
presents along the median line, a linear ridge orjaphe, which terminates
anteriorly in a papilla corresponding to the inferior opening of the
anterior palatine fossa. The Soft Palate (palatum molle) is a movable
fold suspended from the posterior border of the hard palate, and
forming an incomplete septum between the mouth and the pharynx.
It consists of a fold of mucous membrane, enclosing muscular fibres, an
aponeurosis, adenoid tissue, vessels, nerves and mucous glands; and is
formed by fibres of the following —
Muscles, 5 on each side, the — levator palati, tensor veli palati, palato-
glossus (m. glosso-palatinus) , palato-phafyngeus (m. pharyngo-
palatinus), and the azygos uvulae (m. uvulae); — the latter forming
with its fellow the — "
314 HUMAN ANATOMY
Uvula, — a conical-shaped, pendulous process, which hangs down from
the middle of the free border of the soft palate.
Glosso- palatine Arch or Anterior Pillar of the Fauces, — arches downward
and forward to the base of the tongue, and contains the glosso-palatine
muscle.
Pharyngo-palatine Arch or Posterior. Pillar of the Fauces, — arches down-
ward and backward to the sides of the pharynx, and contains the
palato-pharyngei (m. pharyngo-palatinus) muscle.
Isthmus Faucium, — the space bounded by the glosso-palatine arches of
both sides, the free border of the palate, and the base of the tongue.
It communicates with the mouth anteriorly and with the pharynx
posteriorly.
The Tonsils (tonsillae palatinae) or A mygdalee, are two prominent bodies,
situated one on each side, in the sinus tonsillaris between the anterior and
posterior pillars (glosso-palatine and pharyngo-palatine arches) of the
fauces, and nearly an inch in front of the internal carotid artery. Their
inner surfaces show 12 to 15 orifices, leading into recesses, from which
follicles branch out into the substance of the gland. The follicles are
numerous, and are surrounded by a layer of closed capsules of adenoid
tissue, and a plexus of lymphatic vessels communicating with the deep
cervical glands. The —
Fossa Supra-tonsillaris, — is a recess above the tonsil, and is covered by
the plica semilunaris, a fold of mucous membrane.
Arteries, as usually given, are — the dorsalis linguae, from the lingual; the
ascending palatine and tonsillar, from the facial (a. maxillaris
externa); the ascending pharyngeal, from the external carotid;
the descending palatine; from the internal maxillary; and a twig
from the small meningeal. As a matter of fact, in 95 per cent, of
all cases none of these arteries that surround the tonsillar fossa
(sinus tonsillaris) and form a plexus around it, actually penetrate
directly through the wall and capsule into the tonsil. The ascending
palatine branch of the facial (external maxillary) and the^escendin^
palatine branch of the internal maxillary arteries form a plexiform
anastomosis which is quite outside of the fossa (sinus tonsillaris)
and well above and behind it.
The True Tonsillar Artery is formed by this anastomosis, it passes
downwards between the capsule and muscular aponeurosis for a
distance of about % inch before penetrating the capsule to reach
the tonsil (J. Leslie Davis).
Veins, — accompanying the true tonsillar artery is a vein which runs
THE SALIVARY GLANDS 315
upwards to the palatine plexus, a smaller vein emerges from the tonsil
in company with the other vein, then turns downwards and runs be-
tween the capsule and the wall of the fossa (sinus tonsillaris) to reach
the pharyngeal plexus (J. Leslie Davis).
Nerves, — are derived from the spheno-palatine ganglion, and from the
glosso-pharyngeal.
THE SALIVARY GLANDS (GLANDULE SALIVALES)
The Salivary Glands, communicating with the mouth, are the Parotid,
the Stibmandibular, and the Sublingual glands. They are compound, race-
mose glands, consisting of numerous lobes, made up of smaller lobules
connected together by dense areolar tissue, vessels and ducts. Each lobule
consists of the ramifications of a duct, the branches terminating in dilated
ends or alveoli, on which the capillaries are distributed, and which are
enclosed by a reticulated basement membrane. The alveoli are lined by
cells, which secrete a mucous secretion in the sublingual gland, or a serous
fluid in the parotid gland; the submandibular producing both kinds.
Mucous Glands are also found in the mouth, in the tongue, the tonsil, and
the soft palate.
The Parotid Gland (glandula parotis) (i) is the largest of the three
salivary glands, and weighs from % oz. to i oz. Superficially, it lies upon
the side of the face, below and in
front of the external ear, and passes
over the masseter muscle anteri-
orly. Deeply, it lies on the tym-
panic plate of the temporal bone
behind the articulation of the
lower jaw. The parotid is sur-
rounded by a capsule which blends
deeply with the back of the stylo-
mandibular ligament. The super-
ficial portion of this capsule is the
parotid fascia (fascia parotideo-
masseterica). The capsule is de-
rived from the deep cervical fascia,
it is strongly attached to the lower border of the zygoma, the acoustic
meatus, anterior border of the sterno-mastoid muscle, stylo-mandibular
ligament, and the bucco-pharyngeal fascia. It is tenaciously adherent
to the gland itself. Passing through it are the following —
Structures,— the external carotid artery and its terminal branches, the
posterior auricular, temporal, and internal maxillary; the vein formed
HUMAN ANATOMY
by the union of the temporal and internal maxillary veins, the facial
nerve and its branches, branches of the great auricular nerve, and the
auriculo-temporal branch of the mandibular nerve. The internal
carotid artery and the internal jugular vein lie close to its deep
surface.
Stenson's Duct (ductus parotideus) (2), — is the duct of the parotid
gland, and is about 2^ inches long. It begins by numerous branches
from the anterior part of the gland, crosses the masseter muscle,
pierces the buccinator, and opens on the inner surface of the cheek
by a small orifice opposite the 2nd molar tooth of the upper jaw.
Soda Parotidis, — is a small, detached portion of the gland, which
occasionally exists as a separate lobe, just beneath the zygomatic
arch. Its duct empties into Stenson's duct, where the latter crosses
the masseter muscle.
Arteries, — are derived from the external carotid.
Veins, — empty into tributaries of the external jugular.
Lymphatics, — terminate in the superficial and deep cervical glands.
Nerves, — are derived from the carotid plexus of the sympathetic, the
facial, auriculo-temporal and great auricular nerves.
%
The Submandibular Gland (glandula submaxillaris) (3) lies below the
jaw, in the anterior part of the submandibular triangle, and upon the
mylo-hyoid, hyo-glossus, and stylo-glossus muscles, the facial artery (a.
maxillaris externa) lying embedded in a groove in its upper, posterior
border. Its duct —
Wharton's Duct (ductus submaxillaris) (4), — is about 2 inches long, and
opens on the summit of a papilla at the side of the fraenum of the
tongue.
Arteries, — are branches of the facial (external maxillary) and the lingual;
the veins following the course of the arteries.
Nerves, — are branches of the submandibular or submaxillary ganglion,
and are derived through the ganglion from the chorda tympani, the
lingual, and the sympathetic.
The Sublingual Gland (glandula sublingualis) (5) is the smallest of the
salivary glands, and is situated beneath the mucous lining of the floor of
the mouth, at the side of the fraenum (frenulum linguae) of the tongue, and
in contact with the inner surface of the lower jaw. Its ducts, the —
Ducts of Rivinus (ductus sublinguales minores), — from 8 to 20 in num-
ber; some join Wharton's duct (ductus submaxillaris), others open on
the side of the frenulum linguae.
THE TEETH
317
Duct of Bartholin, — is a tube formed by one or more of the preceding
ducts; it opens into Wharton's duct (ductus submaxillaris).
Arteries, — are derived from the sublingual and submental.
Nerves, — are branches from the lingual nerve.
THE TEETH (DENTES)
The Teeth are 32 organs of digestion, situated 16 in each jaw, where
they are implanted within the alveoli, and are partly surrounded by the
gums. In each half of each jaw there are —
Deciduous or Temporary Teeth (dentes dicidui) (5) — 2 Incisors, i
Canine, 2 Milk-molars.
Permanent Teeth (dentes permanentes) (8) — 2 Incisors, i Canine, 2
Premolar, 3 Molars.
The Gums (gingivae) are composed of dense fibrous tissue, closely
connected to the periosteum of the alveolar processes, and surrounding the
necks of the teeth. They are covered with mucous membrane, presenting
numerous fine papillae around the dental margin, and reflected into the
alveoli, where it is continuous with the periosteal lining membrane.
Characteristics of the Teeth. Each tooth consists of a — crown (corona
dentis) or body, projecting above the gum; root or fang (radix dentis),
embedded within the alveolus; and the neck (collum dentis), the constricted
portion between the crown and the fang. The roots are entirely con-
cealed within their alveoli, and are covered by the pericementum (perios-
teum alveolare), a reflection of the periosteum lining the alveoli, which
becomes continuous with the fibrous structure of the gums. The pulp-
cavity (cavum dentis) occupies the centre of the tooth, opening (foramen
apicis) at the apex of the fang for the passage of vessels and nerves to
the pulp (pulpa dentis) . Each class of teeth presents the following charac-
teristics:
HUMAN ANATOMY
FIG. 107.
Incisors, or Cutters (denies incisivi) (i), — Crown chisel-shaped, beveled
posteriorly. Fang single, long, thickest antero-posteriorly.
Canines, or Tearers (dentes canini) (2), — Crown thick and conical.
Fang longest and thickest of all the teeth, forming a projection on the
alveolar arch. The 2 upper canines are the "eye-teeth."
Premolars, or Bicuspids (dentes prasmolares) (3), — Crown has 2 cusps
(tubercles). Fang single but grooved deeply, showing a marked
tendency to bifurcate.
Molars, or Grinders (dentes molares) (4), — Crown large, low and cuboid
in shape, has 4 cusps on upper molars, 5 on the lower ones. Fangs
multiple, usually 3 on the first two upper
molars, 2 on the first two lower ones. The
third molar (dentes serotini) (5) is called
the "wisdom-tooth," from its late eruption;
its fangs are usually fused together into a
grooved cone.
Structure of the Teeth. A tooth consists of 3
structures, — the dentine, or ivory (substantia
eburnea) the proper dental substance, forming
the larger portion; the enamel or adamant (sub-
stantia adamantina), a layer covering the crown;
and the cement (substantia ossea), a thin layer
on the surface of the fang. A central chamber,
the pulp-cavity (cavum dentis), occupies the in-
terior, and contains the pulp (pulpa dentis), a
soft, vascular, and sensitive organ, surrounded
by a layer of cells the odonto-blasts or dentine-
forming cells. The —
Pulp-cavity (cavum dentis), — has a process ex-
tending down each root, and opening at the
apex by a minute orifice (foramen apicis)
which transmits vessels and nerves to the
pulp.
Pulp (pulpa dentis), — is made up of myxoma-
tous tissue, and contains numerous blood-
vessels and nerves, but no lymphatics.
Dentine, or Ivory (substantia eburnea) (2), — consists of tubules (can-
aliculi dentales) surr< unded by the inter-tubular tissue or matrix, and
opening into the pulp cavity (cavum dentis). It resembles compact
bone in appearance and in composition, consisting of 28 parts animal
matter and 72 earthy matter.
THE TEETH 3 19
Dentinal Tubidi (canaliculi dentales), — in the dentine, are delicate,
wavy canals, diameter about M 5 o o of an inch, which branch outwardly
and anastomose with each other, forming concentric shadings called
Schreger's lines. They contain slender prolongations from the proc-
esses of the cells of the pulp-tissue.
Enamel (substantia adamantina) (3), — covers the crown; consists of
very dense tissue, containing but 3^ per cent, of animal matter.
Its earthy matter, 96 ^ per cent., is composed chiefly of the phos-
phate and carbonate of calcium. It is covered by a delicate epithelial
cuticle, Nasmyth's Membrane (cuticula dentis), which when intact
withstands the action of acids.
Crusta Petrosa (substantia ossea) or Cement (i), — the enamel of the
fang; is a thin layer of true bony tissue, containing lacunae, canaliculi,
and occasionally Haversian canals.
Development of the Teeth. The teeth are evolved from the dermoid
system, not from the skeleton. They are developed from two of the primi-
tive layers of the embryo, — the epiblasl producing the enamel (adamant)
and the mesoblast giving rise to the dentine (ivory) pulp, cement (sub-
stantia ossea), and pericementum (periosteum alveolare). About the
7th week of foetal life, two parallel ridges arise along the summit of each
jaw, and a corresponding epithelial lamina sinks into the mesoblastic tissue
beneath. This lamina sends off 10 cords, one for each tooth, from its inner
edge; the cords expand into flask-like forms, and gradually assume
the forms of the teeth, constituting their enamel-organs. They meet and
enclose papilla, which arise from the mesoblastic tissue, forming a series
of sacs, which with their contents are the dental follicles, having fibrous
septa between them. In each follicle the vascular papilla has on its
surface a layer of cells, named odontoblasts, from which the dentine (ivory)
is developed by calcification, the remainder of the papilla forming the pulp
of the tooth. The cement (adamant) is produced later by the tissue of
the dental sac, in the same manner as bone is produced by periosteum.
When calcification has advanced sufficiently, the pressure of the teeth
causes the absorption of the gum above them, the teeth erupt, and the
fibrous septa ossify, forming the alveoli, which embrace the necks of the
teeth in a firm hold.
The 10 permanent teeth, which replace the temporary ones in each jaw,
are developed from special germs (enamel-organs) which arise from the
lamina behind the germs for the temporary teeth, and recede into the
tissue, to enclose mesoblastic papillae, and go through the same process
as described for the temporary teeth. These germs appear about the i6th
320 HUMAN ANATOMY
week. The 6 superadded permanent teeth arise from successive back-
ward extensions of the lamina, projected from the back of that tor each
preceding tooth, and thus forming a special dental germ for each added
tooth.
Eruption of the Teeth. The temporary teeth begin to appear through
the gum at the 7th month after birth, the lower central incisors appearing
first. Their eruption ends with the appearance of the second molars,
about the age of two years. The lower teeth slightly antedate the upper.
Their formula is as follows : —
Mo. Mo. Ca. In. In. In. In. Ca. Mo. Mo.
f Upper. ,.i i i i i i i i i i = 10 1
j \. = 20
[ Lower. .. i i 1111111 i =ioJ
24 12 18 9 7 7 9 18 12 24 months.
Of the permanent teeth, the first molars appear about the end of the 6th
year, followed by the incisors about the 7th or 8th year, the bicuspids
from the 9th to the loth year, the canines about the nth or i2th year,
the second molars from the i2th to the i3th year, and the third molars
from the i7th to the 2ist year. Those of the lower jaw are slightly in
advance of the corresponding upper ones. Their formula is as follows: —
Wis.Mo.Mo.Pm.Pm.Ca.In.In.In.In.Ca.Pm.Pm.Mo.Mo.Wis.
r Upper, i i i i i i iiiiii i i i 1=16]
f32
I Lower, i i i i i 1111111 i i i i = 16 J
19 12 6 10 9 ii 8 7 7 8 n 9 10 6 12 19 years.
The greatest number of teeth at one time in the jaws is 48, — including all
the temporary and permanent teeth except the third molars, if none have
been lost. This occurs between the 5th and 7th years of age.
THE PHARYNX
The Pharynx is a conical, musculo-membranous tube, about 4^ inches
long, hung base up from the basilar process of the occipital bone, and
extending to the lower border of the cricoid cartilage posteriorly, or the
5th cervical vertebra, where it becomes continuous with the oesophagus (5).
It forms that part of the alimentary canal which lies behind the mouth,
being incomplete in front where it opens into that cavity. From above
downward it may be divided into — the naso-pharynx (pars nasalis),
above the level of the soft palate; the oral part (pars oralis), between
THE PHARYNX
321
FIG. 108.
the levels of the soft palate and the hyoid bone; and the laryngeal part
(pars laryngea), below the latter level. It is connected with —
Anteriorly, — the internal pterygoid plate, pterygo-mandibular ligament,
lower jaw, base of the tongue, cornua of the hyoid bone, stylo-hyoid
ligament, thyroid and cricoid cartilages of the larynx.
Posteriorly, — the longus colli and recti
capitis anticus muscles, and by loose
areolar tissue to the first 5 cervical
vertebrae.
Laterally, — the styloid processes and
their muscles, and is in contact with
the common and internal carotid arte-
ries, the internal jugular vein, the Qth,
loth, 1 2th and sympathetic nerves,
and above with a small part of the
internal pterygoid muscles.
Above, — it is limited by the body of the
sphenoid bone, and the basilar process
of the occipital bone.
Openings into the Pharynx, — are 7 in
number; the 2 posterior nares, (choanse),
the 2 Eustachian tubes (tubae audi-
tivae), the mouth, the larynx and the
oesophagus.
The Naso -pharynx (pars nasalis pharyn-
gis) is that portion of the pharynx lying be-
hind the nose and above the level of the
soft palate. Its cavity, unlike the rest of
the pharynx, always remains open. The —
Eustachian Tube (tuba auditiva), — opens
on its lateral wall, by a cleft-like orifice
(ostium pharyngeum tubae auditivae),
behind the inferior meatus of the nose,
and just above the level of the floor of
the nasal fossa.
Pharyngeal Tonsil, — a mass of lymphoid
tissue, in the back wall of the pharynx,
between the two Eustachian tubes (tubae auditivae).
Bursa Pharyngea, — an irregular depression of the mucous membrane
in the jniddle line of the pharynx, above the pharyngeal tonsil.
Cushion (torus tubarius) or Tubal Prominence,— immediately behind
322 HUMAN ANATOMY
the orifice of the Eustachian tube (ostium pharyngeum tubae auditivae),
due to the pressure of the extremity of the cartilage of the tube.
Fossa ofRosenmiiller, — a deep recess, behind the cushion (torus tubarius).
Structure of the Pharynx. The pharynx is composed of 3 coats, — a
mucous, a muscular and a fibrous, the latter lying between the other two,
and called the pharyngeal aponeurosis (fascia pharyngo-basilaris) (4).
The mucous coat is covered with ciliated columnar epithelium above the
level of the floor of the nares — below that level with squamous epithelium;
and contains racemose mucous glands, especially around the orifices of the
Eustachian tubes (ostia pharyngea tubarum auditivarum), also numerous
crypts or recesses, surrounded by lymphoid tissue. The —
Pharyngeal Aponeurosis (fascia pharyngo-basilaris) (4), — is thick
above, where it is firmly attached to the basilar process of the
occipital bone, and the petrous portion of the temporal bone. Pos-
teriorly it presents a fibrous band or raphe in the median line, which
gives attachment to the constrictor muscles.
Muscles, — are the inferior (i), middle (2), and superior (3) constrictors
of the pharynx, the stylo-pharyngeus and the palato-pharyngeus (m.
pharyngo-palatinus), which have been described on page 83.
Vessels and Nerves. The Arteries of the pharynx are the superior
thyroid and ascending pharyngeal, also the pterygo-palatine and descend-
ing palatine branches of the internal maxillary; all from the external
carotid. The nerves are branches from the —
Pharyngeal Plexus, — formed by the pharyngeal branches of the vagus,
glosso-pharyngeal, external br. of the superior laryngeal, and superior
cervical ganglion of the sympathetic.
? *> !?*y THE (ESOPHAGUS OR GULLET
The (Esophagus is a musculo-membranous tube, about 9 inches long,
extending from the 5th cervical vertebra and the upper border of the
cricoid cartilage of the larynx, through the cesophageal opening (hiatus
oesophageus) in the diaphragm to the cardiac orifice (cardia ventriculi)
of the stomach, where it terminates opposite the loth thoracic vertebra.
In the neck it lies between the trachea and the vertebral column, resting
in part on the longus colli muscle; then inclining to the left side it reaches
the posterior mediastinum behind the left bronchus, and descends in that
mediastinum, at first in front of the thoracic duct, lower down to its left.
The (Esophagus is composed of 3 coats, as follows: —
Muscular Coat (tunica muscularis), — has longitudinal fibres externally,
circular fibres internally, which are continuous with the fibres of the
THE ABDOMEN 323
stomach below, and with those of the inferior constrictor muscle
above.
Areolar Coat (tela submucosa), — forms a loose connection between the
other two coats, and contains the cesophageal vessels.
Mucous Coat (tunica mucosa), — in thick longitudinal folds, covered
with a layer of stratified pavement epithelium. The oesophagus is
loosely surrounded by an additional areolarcoat (tunica adventitia)
which loosely connects it to the surrounding structures.
(Esophageal Glands (glandulae cesophageas), — are compound racemose
glands, situated in the submucous tissue throughout the tube, but most
numerous at the lower end, close to the cardiac orifice (cardia ventriculi)
of the stomach.
Arteries, — are chiefly branches from the thoracic aorta.
Veins, — empty into the vena azygos minor.
Nerves, — are branches from the cesophageal plexus (plexus gullae), which is
formed by branches from the vagus and the cervical sympathetic.
THE ABDOMEN
The Abdomen is a large, oval-shaped cavity, situated between the
thorax above and the pelvis below, and bounded — above, by the diaphragm;
below, by the brim of the pelvis; posteriorly, by the vertebral column, and
the fasciae covering the psoaeand quadrati lumborum muscles; anteriorly
and laterally, by the transversalis fascia, the lower ribs and the venter of the
ilium. It is invested internally by the Peritoneum, and it contains the —
Stomach. Pancreas. Abdominal Aorta.
Intestines. Kidneys and Ureters. Inferior Vena Cava.
Liver. Supra-renal Capsules. Receptaculum Chyli.
Gall-bladder. Bladder (when distended). Thoracic Duct.
Spleen. Uterus (during pregnancy). Solar Plexus, etc.
Regions of the Abdomen (Regiones Abdominis). The abdomen is
divided into 9 regions by two horizontal planes, — one at the level of the
cartilages of the loth ribs (sub-costal plane), another at the level of the
highest points of the crests of the ilia, and 2 vertical or lateral planes
from the cartilages of the 8th ribs to the centre of Poupart's inguinal liga-
ment. The 9 regions thus formed are named the —
Right Hypochondriac. Epigastric. Left Hypochondriac.
Right Lumbar. Umbilical. Left Lumbar.
Right Inguinal or Iliac. Hypogastric. Left Inguinal or Iliac.
324 HUMAN ANATOMY
Parts contained in each region are as follows: —
Right Hypochondriac Region, — contains the right lobe of the liver,
hepatic flexure of the colon, and part of the right kidney.
Epigastric Region, — contains the right two-thirds of the stomach, left
lobe and part of the right lobe of the liver, gall-bladder, duodenum,
cceliac axis, solar plexus, pancreas, parts of the aorta, inferior vena
cava, vena azygos, and thoracic
duct, the supra-renal capsules and
parts of the kidneys.
Left Hypochondriac Region, — con-
tains the fundus of the stomach,
spleen, tail of the pancreas, splenic
flexure of the colon, and part of
the left kidney.
Right Lumbar Region, — contains the
ascending colon, lower half of
the right kidney, and part of the
small intestine.
Umbilical, — contains the transverse
colon, transverse duodenum, part
of the great omentum and mesentery, and part of the small intestine.
Left Lumbar Region, — contains the descending colon, lower half of the
left kidney, and part of the small intestine.
Right Inguinal or Iliac Region, — contains the right ureter, caecum, ap-
pendix vermiformis, and the spermatic vessels of that side.
Hypogastric Region, — contains convolutions of the small intestine, the
bladder in children and in adults when distended, and the uterus dur-
ing pregnancy.
Left Inguinal or Iliac Region, — contains the left ureter and spermatic
vessels, and the sigmoid flexure of the colon.
Apertures in the Walls of the Abdomen are 8 in number, for the trans-
mission of structures to or from it, as follows: the —
Opening for the Vena Cava (foramen venae cavae), — in the diaphragm.
Aortic Opening (hiatus aorticus), — behind the diaphragm, for the aorta,
vena azygos minor, thoracic duct, and occasionally the left sympathetic
nerve (see page 94).
(Esophageal Opening (hiatus cesophageus), — in the diaphragm, for the
cesophagus, and the pneumogastric nerves (see page 94).
Umbilical Opening, — in the anterior wall, transmitting the umbilical
vessels in the foetus, but obliterated after birth, leaving a puckered
depression, named the umbilicus.
THE PERITONEUM
325
FIG. no.
Internal Abdominal Ring (annulus inguinalis abdominis), — on each side,
half an inch above Poupart's ligament, for the passage of the sper-
matic cord in the male, and the round ligament of the uterus in the
female (see page 384).
Femoral or Crural Ring (annulus femoralis), — on each side, just
below Poupart's inguinal ligament; for the passage of the femoral
vessels. This opening is closed by the crural or femoral septum
(see page 388).
THE PERITONEUM
The Peritoneum (peritonaeum) is a large serous membrane, which forms
in the male a closed sac, the parietal layer (peritonaeum parietale) of which
lines the abdominal walls, its
visceral layer (peritonaeum vis-
cerale) being reflected more or
less completely over all the
abdominal and pelvic viscera.
Its free surface is covered
with endothelium, and is
smooth, moist, and shining.
Its attached surface is con-
nected to the viscera and the
11 parietes of the abdomen by
the sub-peritoneal tela or
areolar tissue (tela subserosa).
In the female it is not a closed
sac, the free extremities of the
Fallopian tubes opening di-
rectly into its cavity. The
peritoneum is divided by a
constricted portion of its tis-
sue, at the foramen of Winslow
(foramen epiploicum) (9),
into 2 sacs, the —
Greater Sac (cavum peri-
tonaei), — extends over the
anterior two-thirds of the
liver (i), behind and
above the stomach (3); below, behind, and in front of the great
omentum, and below the meso-colon (12).
Lesser Sac (bursa omentalis) or Cavity of the Great Omentum, — extends
behind and below the liver and stomach, above the meso-coion,
326 HUMAN ANATOMY
within the great omentum, and behind the small or gastro-hepatic
omentum (ligamentum hepatogastricum) (2).
The Foramen of Winslow (foramen epiploicum) (9) is an opening which
connects the two peritoneal sacs with each other. It is formed by an hour-
glass constriction of the peritoneum caused by the hepatic artery in its
curved passage forward and upward from the coeliac axis to the transverse
fissure of the liver. It is situated behind the free border of the lesser
or gastro-hepatic omentum (ligamentum hepatogastricum) (2), immedi-
ately below the caudate lobe of the liver, and is bounded as follows: —
Anteriorly, — the lesser or gastro-hepatic omentum (ligamentum hepato-
gastricum) (2), containing the hepatic artery, portal vein, and the
ductus communis choledochus.
Posteriorly, — the inferior vena cava, and the right crus of the diaphragm.
Superiorly, — the caudate lobe (processus caudatus) of the liver.
Inferiorly, — the duodenum, and the hepatic artery.
The Omenta are peritoneal folds which pass from the external surface
of the stomach (3) to various other organs, and are named the lesser or
gastro-hepatic, the great or gastro-colic, and the gastro- splenic omentum.
The "B.N.A." disregards this distinction and classes them with the
true ligaments.
Lesser or Gastro-hepatic Omenlum (ligamentum hepatogastricum) (2),
— consists of two layers of peritoneum, the anterior layer belonging
to the greater sac (cavum peritonaei), the posterior to the lesser
sac (bursa omentalis). It ascends from the lesser curvature of the
stomach (3) to the transverse fissure of the liver (porta hepatis)
(i) and the end of the resophagus. Its right margin is free and
rounded, and contains between its layers the —
Hepatic Artery and Portal Vein. Ductus Communis Choledochus.
Hepatic Plexus of Nerves. Lymphatics.
Great or Gastro-colic Omentum (omentum majus), — consists of 4 layers of
peritoneum, the most anterior and superior of which belong to
the greater sac (cavum peritonaei), the two internal to the lesser sac
(bursa omentalis). The two anterior layers descend from the
stomach and spleen over the small intestines (6), and then ascend
as the posterior layers to enclose the transverse colon (4).
Castro-splenic Omentum (ligamentum gastrolienale), — connects the
stomach with the spleen, and is continuous by its lower border with
the great omentum. It contains the vasa brevia vessels (aa. gastricae
breves).
THE PERITONEUM 327
The Mesenteries (mesenteria) are folds of peritoneum connecting the
various parts of the intestinal canal (except the duodenum) to the posterior
abdominal wall. Each one contains the vessels of the part which it sup-
ports. They are the —
Mesentery proper (mesenterium commune) (5), — connects the convolu-
tions of the jejunum (6) and ileum to the posterior abdominal wall,
and contains between its layers the mesenteric vessels and nerves,
the lacteals, and the mesenteric glands.
Transverse Mesa-colon (mesocolon transversum) (12) — connects the
transverse colon to the posterior abdominal wall, and is formed by
the two posterior layers of the great omentum (omentum ma jus).
Sigmoid Meso-colon (mesocolon sigmoideum), — connects the sigmoid
flexure of the colon to the left iliac fossa.
Meso-rectum, — connects the upper part of the rectum (14) to the front
of the sacrum, and contains the superior hemorrhoidal vessels.
Ligaments formed by the Peritoneum are 1 7 folds of peritoneum which
support certain organs, viz. —
Castro-splenic (lig. gastrolienale), — from the stomach to the spleen.
Hepatic (ligamenta hepatis), — the longitudinal (lig. falciformehepatis),
coronary (lig. coronarium hepatis), and 2 lateral ligaments of the
liver (lig. triangulare dextrum et lig. triangulare sinistrum).
Splenic (lig. lienorenale), — the suspensory ligament of the spleen.
Vesical, — the false ligaments of the bladder, 5 in number.
Uterine, — 2 vesico-uterine, 2 recto-uterine, and 2 lateral or broad liga-
ments of the uterus.
Pouches formed by the Peritoneum, as it passes over the rectum (14),
vagina, uterus (7) and bladder (8), are as follows: the —
Recto-vesical Pouch (excavatio rectovesicalis), — in the male, between the
rectum and the bladder.
Recto-vaginal or Douglas' Pouch (excavatio rectouterina or cavum
Douglasi), — in the female, between the rectum and the posterior
vaginal wall.
Utero-vesical Pouch (excavatio vesicouterina), — in the female, between
the anterior wall of the uterus and the posterior wall of the bladder.
Retro -peritoneal Fossae are recesses of the peritoneum, forming small
pouches in certain parts of the abdominal cavity; any one of which may be
the site of a retro-peritoneal hernia, and hernia of the vermiform appendix
(processus vermiformis) frequently occurs into one of the pericaecal
group. The lesser sac of the peritoneum may be regarded as a recess of
328 HUMAN ANATOMY
peritoneum through the epiploic foramen of Winslow. The others are
divided into 3 groups, as follows : —
Duodenal Fosses, — 9 have been described, of which 3 are fairly constant,
viz.; the inferior, and superior,. both on the left side of the ascending
portion of the duodenum (n); and the duodeno-jejunal (recessus
duodenojejunalis), bounded above by the pancreas (10), below by
the left renal vein, to the right by the aorta (13), and to the left by the
left kidney.
Periccecal Fossa, — are the ileo-colic (recessus ileocecalis anterior), in
front of the caecum; the ileo-cacal (recessus ileocecalis posterior),
behind the angle of junction of the ileum and caecum; and the sub-
ccBcal (recessus ileocecalis inferior), immediately behind the caecum.
Intersigmoid Fossa, — lies behind the sigmoid meso-colon, and in front
of the parietal peritoneum, on the external iliac vessels. It is con-
stant in the foetus and during infancy, but disappears in a certain
percentage of cases as age advances.
^Appendices Epiploica, — are small pouches of peritoneum situated along
the colon and upper third of the rectum, and filled with fat. They
are chiefly found along the transverse colon.
Viscera invested by Peritoneum are the following-named: —
Liver (i) (almost wholly). ' Transverse Colon (4).
Stomach (3) (almost wholly). Sigmoid Flexure.
Spleen. Rectum (upper ^).
Duodenum (n) (first part). Ovaries.
Small Intestine (6). Uterus (7).
Those partially invested by peritoneum are the — •
Duodenun (descending and Descending Colon.
transverse portions). Rectum (14) (middle third).
Ccecum. Vagina (upper part).
Ascending Colon. Bladder (8) (posterior wall).
Those having no peritoneal investment are the — -
Pancreas (10). Kidneys. Supra-renal Capsules (glandulae
suprarenales) (see page 324).
THE STOMACH (VENTRICULUS)
The Stomach, the principal organ of digestion, is a dilated part of the
alimentary canal, situated between the termination of the oesophagus and
the beginning of the small intestine. It is somewhat pyriform in shape,
of musculo-membranous structure, about 12 inches long by 4 inches in
average diameter, held in position by the lesser omentum, and situated
diagonally across the upper abdomen, in the epigastric and left hypochon-
THE STOMACH
329
driac regions, above the transverse colon, below the liver and diaphragm
It presents for examination a —
Fundus or Upper End (c), — connected to the spleen by the gastro-
splenic omentum (see under PERITONEUM).
Pyloric or Lower End, — lies in contact with the anterior wall of the ab-
domen, the under surface of the liver, and the neck of the gall-bladder,
its position being near the
end of the cartilage of the
8th rib.
Greater Curvature (curvatura
ventriculi major) (d), — is
convex and is connected
to the colon by the great
omentum.
Lesser Curvature (curvatura
ventriculi minor) (i), — is
concave, and connected
to the liver by the lesser
omentum, and to the dia-
phragm by the gastro-
phrenic ligament.
(Esophageal Orifice (cardia) (b), — is situated between the fundus and
the lesser curvature. It is funnel-shaped, and the highest part of
the organ.
Pyloric Orifice (pylorus) (k), — opens into the duodenum (/), and is
guarded by the circular muscular fibres of the pylorus, which are ag-
gregated into a circular ring, projecting into the cavity, and with its
covering fold of mucous membrane, forming the Pyloric valve.
Structure of the Stomach. Its wall consists of 4 coats, — the serous,
muscular, areolar, and mucous; together with vessels and nerves. The —
Serous Coat (tunica serosa), — is derived from the peritoneum, and covers
the whole external surface, excepting the points where the gastro-
splenic, great and lesser omenta are attached, and where the stomach
is in contact with the diaphragm.
Muscular Coat (tunica muscularis) (/), — consists of longitudinal (stratum
longitudinale) external, circular (stratum circulare) middle, and
oblique (fibrae obliquae) internal. The longitudinal fibres radiate
from the cardiac orifice, are continuous with the longitudinal fibres
of the oesophagus and the small intestine, and are the most superficial.
The circular fibres lie deeper, form a layer over the whole organ, and
330 HUMAN ANATOMY
are aggregated into a circular ring at the pyloric end, which, with its
lining mucous fold forms the pyloric valve. The oblique fibres lie
deepest, and are arranged in two sets around the cardiac end.
Areolar or Sub-mucous Coat (tela submucosa), — consists of loose areolar
tissue, connecting the muscular and mucous coats, and contains the
gastric vessels.
Mucous Coat (tunica mucosa) (g), — lined with columnar non-ciliated
epithelium, covered with polygonal alveoli, H 50 of an incn in diameter,
containing the orifices of the gastric glands. When the stomach is
contracted the mucous membrane lies in longitudinal folds or ruga
(h), one of which aids in forming the valve at the pyloric orifice.
Gastric Glands (glandular gastricae) are of 3 kinds, named pyloric,
cardiac and fundus glands, all tubular in character, and formed by a deli-
cate basement membrane, lined by epithelium. The —
Pyloric Glands, — are most numerous at the pyloric end; each consists of
2 or 3 short, closed tubes, opening into a common duct, the orifice
of which is situated at the bottom of an alveolus. They are lined with
columnar epithelium throughout.
Cardiac Glands, — situated close to the cesophageal opening (cardia) of
the stomach, are tubules lined part way with columnar epithelium,
and filled with nucleated cells in their deepest parts.
Fundus Glands, — are most numerous at the fundus and resemble the
pyloric glands. L"( cJc
Vessels and Nerves. The Arteries of the stomach are — the gastric
(a. gastrica sinistra), the pyloric (a. gastrica dextra) and right gastro-
epiploic branches of the hepatic, the left gastro-epiploic and vasa brevia
from the splenic (a. lienalis). The —
Veins, — terminate either in the splenic (v. lienalis) and superior mes-
enteric veins, or directly in the portal vein.
Nerves, — are terminal branches of the right and left pneumogastrics
(nn. vagi), and branches of the semilunar ganglia (ganglia coeliaca)
of the sympathetic, forming the gastric plexus (see page 241).
THE SMALL INTESTINE
The Small Intestine (intestinum tenue) is a convoluted, tubular,
digestive organ, about 20 feet in length, extending from the pylorus to
the ileo-caecal valve, where it terminates in the large intestine. It is
connected to the spinal column by the mesenteric portion of the perit-
oneum, and divided into 3 parts, the —
THE SMALL INTESTINE
331
FIG. 112.
Duodenum (d), — about 10 inches long, the first part (pars superior)
ascends for 2% inches to the under surface of the liver and the neck
of the gall-bladder, the second part (pars descendens) descends for
3^ inches in front of the right kidney, and the third part (pars hori-
zontalis inferior) passes transversely for 4 inches to the left, across
the spinal column, to the left side
of the second lumbar vertebra,
where the superior mesenteric
artery crosses its junction with the
jejunum. The last inch of the
duodenum is described as the
fourth or ascending portion (pars
ascendens). The duodenum has
no mesentery, is partially covered
with peritoneum, and surrounds
the head of the pancreas. Into
its descending portion open the
ductus communis choledochus and
the pancreatic duct.
Jejunum (intestinum jejunum), —
about two-fifths of the rest of the
small intestine, its coils lying
around the umbilical region. It is
named from the fact that it was
formerly supposed to be found
empty (jejunus} after death.
Ileum (intestinum ileum) (i), — com-
prises the remainder of the small
intestine; is named from its twisted
course, lying below the umbilicus,
and terminating in the right iliac
fossa, at the ileo-cacal valve, or valve
of Bauhin.
Meeker s Diverticulum (diverticulum ilei), — is a blind tube occasionally
found connected with the ileum, about 3^ feet above its termination;
it represents the remains of the vitelline duct of early foetal life.
Structure of the Small Intestine, is arranged in 4 coats, like that of the
stomach, a serous, muscular, areolar, and mucous coat. The —
Serous Coat (tunica serosa), — is derived from the peritoneum, which
partially invests the duodenum, and completely invests the jejunum
332 HUMAN ANATOMY
and ileum, except for a small space along their mesenteric border,
where the vessels and nerves pass in.
Muscular Coat (tunica muscularis), — consists of external longitudinal
(stratum longitudinale) and internal circular (stratum circulare)
fibres, the former being thinly distributed along the bowel, the latter
forming a thick layer, but not making complete rings.
Areolar Coat (tela submucosa), — contains the vessels of the intestine,
and connects the muscular and mucous coats together.
Mucous Membrane (tunica mucosa), — is covered with columnar non-
ciliated epithelium, and thrown into crescentic transverse folds, the
valvulce conniventes (plicae circulares), or valves of Kirkring. It pre-
sents also numerous vascular projections or Villi (villi intestinales),
simple follicles, and three kinds of glands (all described below).
Villi (villi intestinales) (/) are minute, vascular processes, which project
from the mucous membrane of the small intestine throughout its whole
extent, giving to its surface a velvety appear-
ance. They are most numerous in the duode-
num and jejunum, and altogether number
about 4 millions for the whole length of the
intestine. Each villus consists of a lacteal
vessel, a plexus of capillary blood-vessels,
epithelium, basement membrane, and mus-
cular tissue, supported and held together by
retiform lymphoid tissue. The —
Lacteal Vessel, — is situated in the axis of the
villus, and commences by dilated extrem-
ities near its summit.
Blood-vessels, — form a plexus between the
lacteal and the basement membrane, enclosing the cells of the villus
in their interstices.
Basement Membrane, — surrounds the preceding, and is made up of a
stratum of endothelial cells, upon which is a layer of columnar
epithelium.
Muscular Tissue,— consists of longitudinal fibres prolonged into the vil-
lus from the muscular tissue of the mucosa.
Simple Follicles, or Crypts of Lieberkiihn (glandulae intestinales), — are
minute, tubular depressions of the mucous membrane, opening be-
tween the villi, their orifices appearing as minute dots on the surface
of the mucous membrane.
Glands of the Small Intestine. The mucous membrane of the small
intestine contains the following glands: —
THE LARGE INTESTINES 333
Duodenal or Brunner's Glands (glandulae duodenales), — are small, com-
pound glands, found only in the duodenum and the first part of the
jejunum, being most numerous near the pylorus. In structure they
are identical with the racemose glands of the mouth.
Solitary Glands (noduli lymphatici solitarii), — are lymphoid organs,
situated throughout the intestine, though most numerous at the lower
portion of the ileum. They are agminated into some 20 or 30 oval
patches, named —
Peyer's Patches or Glands (noduli lymphatici aggregati), — on the sur-
face opposite to the mesenteric attachments, some of which are as
much as 4 inches in length. They are most numerous and largest in
the ileum, are few and small in the jejunum, and are occasionally seen
in the duodenum.
Vessels and Nerves. The Arteries of the jejunum and ileum are
branches of the superior mesenteric artery, forming an intricate plexus
in the areolar tissue, which gives off minute vessels to the glands and villi.
The duodenum is supplied by the pyloric (a. gastrica dextra) and pan-
creatico-duodenal branches of the hepatic, and the inferior pancreatico-
duodenal from the superior mesenteric. The —
Veins, — accompany the arteries and have a similar course and arrange-
ment.
Lymphatics, — are in two sets, one for the mucous membrane and one
for the muscular coat.
Nerves, — of the duodenum are derived from the solar plexus (plexus
cceliacus); those of the rest of the intestine from the sympathetic
plexuses around the superior mesenteric artery.
THE LARGE INTESTINE (INTESTINUM CRASSUM)
The Large Intestine (intestinum crassum) extends from the termination
of the ileum to the anus. It is about five feet long, of large calibre, and
consists of the same coats as the small intestine, the mucous being smooth
and without villi, the muscular having its longitudinal fibres collected into
3 narrow bands (taeniae coli) producing a sacculation (pouching) of its wall.
In its course it describes an arch around the convolutions of the small
intestine, and is divided into 3 portions, the Caecum, the Colon, and the
Rectum.
The Caecum (intestinum caecum) is a large blind pouch, about 2% inches
long and 3 inches broad, situated in the right iliac fossa, immediately
behind the abdominal wall, above the outer half of Poupart's ligament (liga-
mentum inguinale), and below the ileo-caecal valve, which opens into it.
334 HUMAN ANATOMY
It lies free in the abdominal cavity, its closed end downward, its open end
upward and continuous with the commencement of the colon. It is usu-
ally enveloped entirely by peritoneum, and presents for examination the — •
Vermiform Appendix (processus vermiformis), — a narrow, worm-like,
blind tube, averaging 3 inches in length, directed upward behind the
caecum, or to the left behind the ileum, or downward and inward into
the true pelvis. Its canal communicates with the caecum by an orifice
situated below and behind the ileo-caecal opening. Sometimes the
orifice of the vermiform process is partially guarded by a crescentic
fold of mucous membrane (valvula processus vermiformis) which is
produced on its upper border. Its proximal % is retained in
position by a triangular mesentery, its distal ^<j is free and com-
pletely covered by peritoneum.
Heo-ccBcal Valve, or Valve of Bauhin (valvula coli), — guards the en-
trance of the small intestine, and is formed by two crescentic folds of
the mucous and cellular coats and circular muscular fibres (labium
superius et labium inferius) each fold being covered with villi on the
side toward the ileum, but smooth on the caecal side.
The Colon is divided into 4 parts, — the ascending, transverse, and de-
scending colon and the sigmoid flexure. The Ascending Colon (colon
ascendens) (ac) extends from the caecum upward on the right side of the
abdominal cavity, to the under surface of the liver, where it turns to the
left, forming the hepatic flexure (flexura coli dextra). The Transverse
Colon (colon transversum) (tc) crosses the abdomen from right to left
to the lower end of the spleen, where it curves downward, forming the
splenic flexure (flexura coli sinistra). The Descending Colon (colon de-
scendens) (dc] passes downward along the outer border of the left kidney,
then inward along the outer border of the psoas muscle to the crest of the
ilium, where it terminates in the Sigmoid Flexure (colon sigmoideum) or
pelvic colon. The latter is curved like an /, first upward and forward,
then downward into a loop, which terminates in the rectum, opposite the
left sacro-iliac symphysis. The — •
Peritoneum, — covers the transverse colon and the loop of the sigmoid
flexure almost completely, forming the transverse mesocolon and the
sigmoid mesocolon. It covers the ascending and descending colon
and the upper part of the sigmoid flexure on their anterior surface and
sides.
Mesocolon, — is the mesentery of the colon, connecting the transverse por-
' tion to the posterior abdominal wall in all cases; but exists for the
ascending colon in 26 per cent., and for the descending colon in 36
THE LARGE INTESTINE 335
per cent, of the cases. The sigmoid mesocolon connects the loop of the
sigmoid flexure to the psoas fascia.
Phreno-colic Ligament, — is a fold of peritoneum, connecting the com-
mencement of the descending colon with the diaphragm.
Appendices Epiploicce, — are small pouches of peritoneum containing fat,
and found along the colon and part of the rectum. They are chiefly
appended to the transverse colon.
The Rectum (intestinum rectum) (r) is the terminal portion of the large
intestine, and extends from the sigmoid flexure (colon sigmoideum) or
pelvic colon to the anal orifice (a). It is about 8 inches long, not saccu-
lated, and, though not straight, is straighter than the rest of the gut. It
curves laterally to the middle of the sacrum, and backward about an inch
above its termination at the anus, where it forms an antero-posterior slit,
having its lateral walls in apposition, but capable of considerable disten-
tion. The relations of the rectum are as follows: —
First Portion, 4 inches long, — lies on the left pyriformis muscle and the
left sacral plexus of nerves; to its left are the left ureter and the
branches of the left internal iliac artery.
Second Portion, 3 inches long, — in the male subject lies just behind the
trigonum vesicae and the vesiculae seminales, and close below the under
surface of the prostate gland. In the female it is adherent to the
central portion of the posterior wall of the vagina.
Third Portion or Anal Canal, i to i^ inch long, — is surrounded by its
sphincters and the levator ani muscle, and is separated by the peri-
naeum from the membranous portion and bulb of the urethra in the
male, from the vagina in the female.
Peritoneum, — invests the first portion almost completely, forming the
mesorectum, which connects it to the sacrum; invests the second por-
tion in front and laterally, and is thence reflected to the' bladder in the
male and to the vagina in the female. The third portion of the rectum
has no peritoneal investment.
Sphincters of the Rectum, — are the internal sphincter and the sphincter
ani (see page 97).
Valves of Houston (plicae transversales recti), — are 3 transverse folds of
the mucous lining, of semilunar shape, one in the upper part of the
rectum on the right side, another about the middle on the left side
and the third in front, opposite the base of the bladder.
Glands of the Large Intestine. The simple follicles are present through-
out its entire length, and are more numerous than in the small intestine.
The solitary glands (noduli lymphatici solitarii) are most abundant in the
336 HUMAN ANATOMY
caecum and appendix, but are scattered irregularly over the entire canal.
Brunner's glands and villi are absent, the valvulae conniventes are almost
wanting.
Vessels and Nerves. The Arteries of the large intestine are the ileo-
colic, colica dextra and colica media from the superior mesenteric, to the
caecum, the ascending colon and the transverse colon; the colica sinistra
and sigmoid branches of the inferior mesenteric, to the descending colon
and the sigmoid flexure; the superior hemorrhoidal from the inferior mesen-
teric, the middle hemorrhoidal from the internal iliac, and the inferior
hemorrhoidal from the pudic (a. pudenda interna), to the rectum. The —
Veins of the Rectum, — commence in a plexus around the lower end, the
hemorrhoidal plexus, which gives off 6 vessels to unite into a trunk,
the superior hemorrhoidal vein. The plexus communicates also with
the tributaries of the middle and inferior hemorrhoidal veins, estab-
lishing a communication between the systemic and portal circulations.
Lymphatics, — open into the mesenteric, lumbar, sacral and inguinal
glands, the latter receiving the vessels from around the anus.
Nerves, — are derived from the sympathetic plexuses around the arteries
which are distributed to the large intestine.
THE LIVER (HEPAR)
The Liver is the largest gland in the body, weighing from 3 to 4 pounds,
and measuring all the way from 3 to 9 inches in various directions. It
is situated in the right hypochondriac, epigastric and part of the left hypo-
chondriac regions; has 5 fissures, 5 lobes, 5 ligaments, and 5 sets of vessels,
and is invested by peritoneum, except for a small space at the attachment
of the coronary ligament. It is also surrounded by a fibrous coat which
is continuous at the transverse fissure with the capsule of Glisson. Its —
Upper Surface (facies superior), — is convex, in relation with the under
surface of the diaphragm and lower 6 or 7 ribs, and is divided into
two lobes by the falciform ligament.
Under Surface (facies inferior) (Fig. 113), — is concave, covers the stom-
ach, duodenum, hepatic flexure of colon (flexura colidextra), right
kidney and supra-renal capsule, and is divided into 5 lobes by 5
fissures.
Posterior Surface (facies posterior), — direct backwards and is in con-
tact with the various structures forming the upper part of the poste-
rior abdominal wall. It is flat in the vertical axis but is deeply
indented by the vertebral column, and deeply grooved by the vena
THE LIVER 337
Anterior Border (margo anterior), — is sharp, and is notched in two places,
one at the fundus of the gall-bladder (vesica fellea), the other at the
round and falciform ligaments. It corresponds to the lower border
of the ribs and costal cartilages, descending a little lower during deep
inspiration and in the upright posture.
Posterior Border (margo posterior), — rounded, and deeply grooved
(sometimes channeled) for the inferior vena cava (13). The anterior
and posterior borders, together form the inferior border (margo
inferior).
Fissures of the Liver are 5 in number, situated on the inferior and
posterior surfaces, and arranged in the form of the letter H. The left
limb of the H is the longitudinal fissure (fossa longitudinalis sinistra),
divided into the umbilical fissure (fossa venae umbilicalis) anteriorly, and
FIG. 114.
the fissure for the ductus venosus (fossa ductus venosi) (8) posteriorly; the
right limb is formed in front by the fissure (fossa vesicae felleae) for the
gall-bladder (9), behind by the fissure (fossa venae cavae) (12) for the vena
cava (13). The connecting bar of the H is the transverse fissure (porta
hepatis). The—
Longitudinal Fissure (fossa longitudinalis sinistra), — separates the left
lobe (lobus hepatis sinister) from the lobus Spigelii (lobus caudatus)
and the lobus quadratus. Its anterior portion, in front of the trans-
verse fissure (porta hepatis), is the umbilical fissure (fossa venae
umbilicalis), containing the umbilical vein in the foetus, and its
33^ HUMAN ANATOMY
remains, the round ligament, in the adult. It is often bridged over
by a process of liver tissue, the pans hepatis. The posterior portion
is the fissure of the ductus venosus (fossa ductus venosi) (8), and lodges
the slender cord which, in the adult, represents that foetal vessel.
Transverse or Portal Fissure (porta hepatis), — is about 2 inches long,
runs from the longitudinal fissure to the right, and transmits the por-
tal vein (7), hepatic artery (6) and nerves, and the hepatic duct (n)
and lymphatics. It separates the quadrate lobe in front from the
caudate (processus caudatus) and Spigelian (lobus caudatus) lobes
behind.
Fissure for the Gall-bladder (fossa vesicae felleae) (9), — on the right of the
longitudinal fissure, and nearly parallel with it, extending from the
anterior border, backward to near the right end of the transverse
fissure.
Fissure for the Vena Cava (fossa venae cavae) (12), — extends obliquely
upward on the posterior surface, and separates the Spigelian lobe
(lobus caudatus) from the right lobe (lobus hepatis dexter). Occa-
sionally this fissure is a complete canal in the substance of the liver.
Lobes of the Liver are 5 in number, but three are mere lobules of the
right lobe, formed by the smaller fissures. The —
Right Lobe (lobus hepatis dexter) (2), — is much the largest, and presents
the three small fissures and four shallow depressions, one anteriorly for
the colon, another posteriorly for the kidney, a third for the
duodenum, and a fourth for the supra-renal capsule (glandula
suprarenalis) .
Left Lobe (lobus hepatis sinister (i), — is divided from the right lobe by
the longitudinal fissure (fossa longitudinalis sinistra), and rests upon
the stomach.
Quadrate Lobe (3), — in front of the transverse fissure (porta hepatis)
and between the umbilical fissure (fossa venae umbilicalis) and that
(fossa vesicae felleae) for the gall-bladder.
Lobus Spigelii (lobus caudatus) (5), — behind the transverse fissure
(porta hepatis), and between the fissure (fossa ductus venosi) for the
ductus venosus and that (fossae venae cavae) for the vena cava.
Caudate Lobe (processus caudatus) (4), — a connecting ridge from the
lobus Spigelii (lobus caudatus) to the right lobe; it separates the
fissure for the vena cava (fossa venae cavae) from the fissure (fossa
vesicas felleae) for the gall-bladder, and lies directly above the foramen
of Winslow (foramen epiploicum).
Ligaments of the Liver are 5 in number, connecting the organ to the
THE LIVER 339
under surface of the diaphragm and the anterior wall of the abdomen.
Four are folds of peritoneum; one, the round ligament, is the obliterated
umbilical vein of the foetus. The —
Suspensory or Falciform Ligament (lig. falciforme hepatis), called also the
Broad and the Longitudinal Ligament, — is a sickle-shaped double fold
reflected over the round ligament (lig. tereshepatis) andis attached to
the sheath of the right rectus muscle as low as the umbilicus, and to the
diaphragm.
Coronary Ligament (ligamentum coronarium hepatis), — is a double fold,
containing firm areolar tissue in its interspace, and extending from the
posterior border of the liver to the diaphiagm.
Lateral Ligaments 2, — are the triangular extremities of the coronary
ligament, and extend from the liver to the diaphragm. They are also
known as the lig. triangulare dextrum and the lig. triangulare sinis-
trum.
Round Ligament (lig. teres hepatis), — ascends in the free margin of the
suspensory ligament (lig. falciforme hepatis) from the umbilicus to the
longitudinal fissure (fossa longitudinalis sinistra), in which it is con-
tinued to the vena cava. It results from the obliteration of the fcetal
umbilical vein, and is continued on the posterior surface as the oblit-
erated ductus venosus (8).
+ tf STRUCTURE OF THE LIVER
» The Liver Substance is composed of numerous lobules (lobuli hepatis)
held together by fine areolar tissue, and the ramifications of the hepatic
artery and veins, portal vein, hepatic ducts, lymphatics and nerves. The
whole organ is invested by a fibrous coat, and by a peritoneal coat for the
greater part of its surface. The — •
Fibrous Coat (capsula fibrosa [Glissoni]), — is formed of connective tissue,
and is inflected at the transverse fissure (porta hepatis) along the ves-
sels, forming the so-called capsule of Glisson.
Peritoneal Coat (tunica serosa), — is derived from the gastro-hepatic
(lesser) omentum, (ligamentum hepatogastricum) between the layers
of which the liver is received, and which forms 4 of its 5 ligaments.
Parts Uninvested by Peritoneum are — on the anterior and superior sur-
faces, along the line between the two layers which form the suspensory
ligament; on the inferior surface, where the gall-bladder is attached, and
at the transverse fissure (porta hepatis) where the vessels enter; on the pos-
terior surface of the right lobe, a strip about 3 inches broad, where the liver
340
HUMAN ANATOMY
is in contact with the diaphragm, also a part of the depression for the supra-
renal capsule (glandula suprarenalis).
The Lobules (lobuli hepatis) (i) are small, granular-looking bodies, of
polygonal shape, and about 3^o inch in diameter, clustered around the sub-
lobular branches of the hepatic veins, and connected together by con-
nective tissue (3), blood-vessels, ducts (2), and lymphatics. Each lobule
consists of a mass of hepatic cells, surrounded by a dense capillary plexus,
and contains the minute beginnings of a bile-duct, the so-called biliary
capillaries; possessing therefore all the essential constituents of a secreting
gland. A lobule contains —
FIG. 115.
Hepatic Cells, — each about Msoo inch in diameter, having a nucleus and
nucleolus, yellow coloring matter, glycogen granules, and oil globules.
Lobular Veins (3), — forming a plexus in the lobule. \ ,
Intralobular Vein (4), — in the centre of each lobule. /
Plexuses, — of lymphatics, nerves, and bile-ducts.
The Capsule of Glisson (capsula fibrosa) is the fibrous tissue which sur-
rounds the hepatic vessels in the transverse fissure (porta hepatis), and
accompanies them in their course throughout the substance of the liver.
It is continuous with the fibrous covering of the organ. The hepatic veins
and their tributaries are not invested by the capsule.
Nerves of the Liver are branches from the hepatic plexus, which is formed
by branches derived from the.cceliac plexus, the left pneumogastric (n.
vagus) and the right phrenic nerves.
THE LIVER
341
FIG. 116.
VESSELS OF THE LIVER
Vessels of the Liver are 5 in number, the hepatic artery, portal vein,
hepatic veins, hepatic ducts (ductus hepaticus), and lymphatics, all
emerging in the transverse fissure except the hepatic veins, which enter the
fissure (fossa) for the vena cava. In the transverse fissure (porta hepatis)
all the vessels are enveloped in the capsule of Glisson, and the duct, artery
and vein are situated from before backward in the order named, repre-
sented by the letters D AV. Four of these vessels are described separately
below, the — •
Lymphatics, — accompany the
blood-vessels in 2 sets, su-
perficial and deep; the latter
beginning in lymphatic
spaces around the capillaries
of the lobules, and accom-
panying the interlobular
vessels. They enter the
lumbar glands, the glands
of the lesser omentum, those
of the oesophagus and of the
lesser curvature of the
stomach.
The Hepatic Artery is the nu-
trient vessel of the liver; it arises
from the cceliac axis, gives off
pyloric, gastro-duodenal and
cystic branches, and passes up-
ward in front of the foramen of
Winslow to the transverse fissure,
where it divides into right and left branches, for the corresponding lobes
of the liver. These divide and subdivide, ramifying in the portal canals
throughout the organ, and giving off the following branches: —
Vaginal Branches, — to the capsule of Glisson.
Capsular Branches, — to the fibrous covering of the liver.
Interlobular (rami arteriosi interlobulares), — forming an arterial plexus
between the lobules.
Lobular, — to the capillary network in the lobules.
The Portal Vein brings blood to the liver from the stomach, intestines,
pancreas and spleen; being formed by the union of the superior and infe-
342 HUMAN ANATOMY
rior mesenteric, splenic and gastric veins, all the main veins of the abdomen
except the renal. It is about 4 inches long, enters the transverse fissure of
the liver, where it divides into the right and left portal veins, these dividing
into branches, which receive vaginal and capsular veins, and ramify
throughout the liver as portal canals (i), in company with the branches of
the hepatic artery and duct; finally breaking up into the —
Inlerlobular Plexus (2), — between the lobules, giving off the —
Lobular Veins (3), — converge to the centre of the lobule, and end in
the—
Intralobular Vein (4), — vertically in the centre of each lobule, enters the
sublobular of the hepatic veins below the lobule.
The Hepatic Veins convey blood away from the liver, and are con-
tinuations of the intralobular veins of the portal system, beginning as the
sublobular veins below each lobule, uniting finally into 3 trunks usually,
which enter the inferior vena cava in the fissure for that vessel. On sec-
tion of the liver the hepatic veins gape open, being adherent to the liver
substance; the portal veins are closed, being surrounded by the capsule of
Glisson.
The Hepatic Ducts carry away bile from the liver. They begin between
the cells of the lobules, in minute spaces, the bile-capillaries, forming
channels which radiate to the circumference of the lobule, and enter an
interlobular plexus between the lobules; from which plexus ducts pass into
the portal canals, are enclosed in the capsule of Glisson with the portal
vein and the hepatic artery, and join with other ducts to finally form 2
main trunks, which emerge at the transverse fissure, and by their union
form the Hepatic Duct (see below).
EXCRETORY APPARATUS OF THE LIVER
The Excretory Apparatus of the liver consists of — the Hepatic Duct,
formed by the union of the two main trunks above-mentioned; the Gall-
bladder, a reservoir for the bile; the Cystic Duct, the duct of the gall-bladder;
and the Ductus Communis Choledochus or common bile-duct, formed by the
junction of the hepatic and cystic ducts. The —
Hepatic Duct, — about i % inches long; is formed in the transverse fissure
by the union of the two main biliary ducts, from the right and left
lobes. It joins the cystic duct from the gall-bladder to form the — •
Ductus Communis Choledochus, or Common Bile-duct, — is a fibro-mus-
cular tube, covered by peritoneum and lined with mucous membrane,
about 3 inches in length, formed by the junction of the Cystic and
Hepatic ducts, and emptying its contents (bile) into the descending
THE PANCREAS 343
part of the duodenum at a point about 3 inches from the pyloric
orifice of the stomach, generally in common with the duct of the
pancreas.
The Gall-bladder (vesica fellea) is a pear-shaped bag, 3 to 4 inches long,
an inch in greatest diameter, holding from 8 to 12 fluid drachms, invested
by peritoneum on its under surface and f undus, formed of a fibrormuscular
coat and lined by a mucous one, lying in a fissure on the under surface of
the liver, close to its anterior border, and directed obliquely downward,
forward, and to the right. Its —
F undus (f undus vesicae felleae), — touches the abdominal wall immedi-
ately below the gth costal cartilage, and is completely invested by
peritoneum.
Neck (collum vesicae felleae), — is narrow and curves like the letter S; it
empties into the —
Cystic Duct (ductus cysticus), — about i^ inches long, is marked inte-
riorly by spirally arranged crescentic folds of its mucous lining, and
joins with the hepatic duct at an acute angle, to form the common
bile-duct (see above).
THE PANCREAS
The Pancreas is a compound racemose gland, about 5 finches long and
i^ inches broad, situated transversely across the posterior wall of the ab-
domen behind the stomach and in front of Jthe first lumbar vertebra.
Its structure resembles that of the salivary glands, being composed of red-
dish-yellow lobules, vessels and ducts, and ending in closed pouches sur-
rounded by a capillary plexus.
It is not enclosed in a capsule^
but is surrounded by areolar
tissue, which extends into its
interior, and connects together
23 * the various lobules. Its —
Head or Right Extremity
(caput pancreatis) (i), —
shaped like the head of a hammer, lies in the concave curve of the
duodenum, in front of the common bile-duct, the inferior vena cava,
the left renal vein, the right crus of the diaphragm, and the aorta.
Neck (2), — about an inch long, lies just below the pylorus, and above
the transverse portion of the duodenum.
Body (corpus pancreatis) (3), — is in relation anteriorly with the ascend-
ing layer of the transverse meso-colon, the posterior wall of the stom-
344 HUMAN ANATOMY
ach and the transverse colon; posteriorly with the aorta, splenic vein
(v. lienalis), origin of the superior mesenteric artery, crura of the
diaphragm, left kidney and supra-renal capsule, and the left quadratus
lumborum muscle.
£gil (cauda pancreatis), or Left Extremity (4), — lies above the left kidney
and in contact with the lower part of the inner surface of the spleen.
Pancreatic Duct, or Duct of Wirsung (5), — extends the whole length of
the gland, commencing by the junction of the lobular ducts in the
tail, it receives the ducts of the various lobules, and opens into the
descending portion of the duodenum, about 3 or 4 inches below the
pylorus, usually by an orifice common to it and the common bile-duct,
occasionally by a separate orifice. Sometimes the pancreatic duct is
branched, in which case the upper branch is known as the duct of
Santorini (ductus pancreaticus accessorius).
'/,- -JK4223& are the~
Pancreatica Magna and Pancreaticae Parvae, — from the splenic
(a. lienalis).
Pancreatico-duodenalis, — branch of the hepatic artery,
inferior Pancreatico-duodenalis, — branch of the sup. mesenteric.
Veins, — open into the splenic and superior mesenteric veins.
Lymphatics, terminate in the lumbar glands.
Nerves, — are filaments from the splenic plexus, which is a subdivision of
the cceliac plexus.
The Lesser Pancreas is a lobe of the head of the pancreas, sometimes
found detached, in which case it opens by a duct into the duodenum about
an inch above the orifice of the pancreatic duct.
DUCTLESS GLANDS
The Ductless Glands are those that discharge their special products
directly into the blood or lymphatic circulation. This is spoken of as
internal secretion, which, however, is not peculiar to this variety of gland,
since many of the other organs such as the liver, pancreas, stomach, in-
testine, kidney, prostate, testis, uterus, ovary, corpus luteum, and possibly
still other organs, form internal secretions in addition to their obvious
functions. The ductless glands are classified as belonging to the following
systems:
^. Chromaphil system.
2. Cortical system.
3. Ductless glands of ento-dermal origin.
4. Ductless glands associated with the vascular system.
THE CHROMAPHIL (chromafnn or phaerochrome) SYSTEM includes those
glands which elaborate adrenin (laevo-adrenalin CgHisNOs of Aldrich)
THE DUCTLESS GLANDS 345
They are so named because their cell cytoplasm contains granules which
are stained bright yellow to dark brown, by salts of chromium. In
this system are included the following: —
1. Paraganglia which are small masses of chromaphil tissue associated
with the ganglia of the sympathetic nervous system. They may be
immediately on the outside, partially within, or entirely within the
capsules of the sympathetic ganglia.
2. Chromaphil Bodies of the Sympathetic Plexuses. These are asso-
ciated with the abdominal sympathetic plexuses; those of the aortic
plexus are called the -aortic bodies which are situated close to the origin
of the superior mesenteric artery.
3. Carotid Glands of Bodies (glomus carotica) are found, one on each
side, in or behind the bifurcation of the common carotid artery.
4. The Large Cells of the Anterior (buccal or glandular) lobe of the
pituitary body (hypophysis) (see page 186).
5. Medullary portions of the supra-renal glands (see page 363).
THE CORTICAL SYSTEM includes several masses of yellow glandular tissue
which is rich in lipoids, there are of these, — •
i'. Cortex of the Supra-renal Glands (see page 363).
2. Accessory Cortical Bodies which are several small masses of cortical
tissue found in relation to the testis and ovary.
DUCTLESS GLANDS OF ENTODERMAL ORIGIN include the following, — •
1 . Small Cells of the anterior (buccal or glandular) lobe of the Pituitary
Body (hypophysis) (see page 186).
2. Thyreoid Gland (glandula thyreoidea) is an incapsulated gland sur-
rounding the front and sides of the upper part of the trachea, and the
sides of the lower part of the larynx, under cover of the omo-hyoid,
sterno-hyoid and sterno-thyreoid muscles.
The Capsule consists of a superficial layer and a deep layer. The
superficial layer of the capsule is derived from the deep cervical
fascia. It is strongly attached to the trachea and the deep cervical
fascia. It is attached loosely by areolar tissue to the deep layer of
the capsule. The interval between the two layers is occupied by
numerous large blood-vessels, the veins in particular, forming a
very large anastomotic plexus.
The thyreoid gland itself usually consists of a right and a left lobe
the lower thirds of which are joined together across the mid-line
by the isthmus. Often there is an upward production of the upper
border of the isthmus forming a pyramidal lobe which is usually
to the left of the mid-line. Running from the lower border of the
hyoid bone to the apex of the pyramidal lobe is the hyo-thyreoid
346 HUMAN ANATOMY
ligament which is sometimes muscular (m. levator glandulae thy-
reoidea); this, together with the attachments of the superficial
layer of the capsule to the trachea and deep cervical fascia, holds
the gland in place.
Deep Layer of the Capsule (tunica propria glandulae thyreoidea) is
intimately attached to the gland itself into the substance of which
it sends many supporting trabeculce and septa accompanied by
blood-vessels.
Structure, — The gland is made up of many irregular masses called
lobules, each lobule consists of several closed vesicles which do not
communicate, each vesicle is lined with a single layer of cuboidal
or columnar cells, and filled with a yellowish viscous substance
called colloid.
Arteries are, — the right and left superior thyreoid branches of the ex-
ternal carotid arteries, right and left inferior thyreoid branches of
the thyreoid axes of the subclavian arteries, and when present, the
thyreoidea ima branch either of the innominate artery or arch of
the aorta.
Veins are, — right and left superior thyr eoid veins which empty into the
internal jugular veins, right and left middle thyreoid veins which,
when present, empty into the internal jugular veins, right and left
inferior thyreoid veins which empty into the innominate veins,
thyreoidea ima vein which when present empties into either the left
innominate vein or left inferior thyreoid vein.
Lymphatics on the left side empty into the upper loop of the thoracic
duct (ductus thoracicus), those of the right side empty into the
right lymphatic duct (ductus lymphaticus dexter).
The nerve supply is from the middle and inferior cervical ganglia of
the sympathetic.
3. Parathyreoid Glands, — are small flattened ovoidal masses of a
yellow or reddish-brown color, they are slightly lighter in color
and of a softer consistency than the thyreoid gland itself. Each is
surrounded by its own individual capsule to which it is strongly
adherent. Each gland possesses a stalk formed by the blood-
vessels entering its hilus. The capsule sends many highly vascu-
lar supporting trabeculae and septa into the substance of the gland
which is composed of solid masses of polyhedral cells. There may
be a considerable variation in both the number and the disposi-
tion of these glands. Normally there should be an upper and a
lower pair.
Superior parathyreoids, — a right and a left, are usually found, nearer
THE DUCTLESS GLANDS 347
the mid-line than the lower pair, on the upper ends or on the dorsal
surface of the upper thirds of the lateral lobes of the thyreoid gland,
inside of and strongly adherent to its capsule; or they may be
imbedded in the areolar tissue between the two layers of the
capsule.
Inferior parathyreoids, a right and a left, usually lie on the dorsal or
lateral surface of the lower thirds of the lateral lobes of the thyreoid
gland, much further from the mid-line than the upper pair, and
more often outside of the capsule. Parathyreoids that have
wandered far from the thyreoid gland can hardly be identified
except under the microscope.
4. Thymus Gland (thymus), — consists of two lateral lobes which
are firmly united, each being attached by a ligament to the lower
end of the lateral lobe of the thyreoid gland above it. The thymus
depends from these suspensory ligaments in the lower part of the
front of the neck downwards into the superior and anterior
mediastina, often reaching the pericardium. In front, it is in rela-
tion to the back of the sternum, the sterno-thyreoid and sterno-
mastoid muscles. Laterally it is in relation to the pleurae. Behind
it are the great blood-vessels which deeply groove its dorsal surface
although actually separated from it by the deep cervico-thoracic
fascia. The thymus is subject to much variation both in size and
shape, usually it is relatively largest at the age of puberty, becoming
progressively smaller thereafter. In color the thymus is reddish
gray, tending to become white or yellow as it undergoes involu-
tion. It is invested by a thin fibrous capsule which sends nu-
merous septa into the gland substance dividing it up into lobules
which in turn are divided up into follicles. Each follicle consists
of a central medulla which is partially surrounded by a cortex
which resembles lymphatic gland tissue.
Arteries are numerous, irregular branches of the internal mammary
and inferior thyreoid arteries.
Veins are numerous and irregular, they empty into the inferior
thyreoid, internal mammary, and left innominate veins.
Nerves are small branches of the vagus which run directly into the
gland, and minute branches of the cervical sympathetic which are
carried in on the arteries.
Lymphatics arise from plexuses around the follicles, pass through the
inter-lobular septa and the capsule to the adjacent lymph
glands.
HUMAN ANATOMY
DUCTLESS GLANDS ASSOCIATED WITH THE VASCULAR
SYSTEM
i. The Spleen (lien) is a soft, brittle, highly vascular organ, of dark
purplish color, in size about 5 by 3 by i% inches, in weight about 7 ounces;
situated deeply in thejeft hypochondrium, between the fundus of the
stomach in front and internally, and the diaphragm behind and externally,
opposite the gth, zoth and nth ribs of thejeft side. It is connected with
the stomach, by the gastro-splenic amentum (ligamentum gastrolienale);
with the diaphragm, by the suspensory or phreno-splenic ligament; and
with the left kidney, by the lieno-renal ligament, all of which are folds of
peritoneum. Its —
Outer. Surface (facies diaphragmatica), — is convex, smooth, and in rela-
tion with the under surface of the diaphragm,
which separates it from the gth, loth and nth
ribs of the left side.
Inner Surface, — is concave, and divisible into two
portions, one that is in contact, anteriorly (2)
with the posterior wall of the cardiac end of the
stomach and the tail of the pancreas (facies gas-
trica), the other portion being in contact posteri-
orly (i) with the left kidney (facies renalis).
Hilum (hilus lienis), — a vertical fissure about the
middle of the inner surface, pierced by apertures
for the vessels and nerves.
Lower End, — is flat and triangular (facies colica or basalis), and rests
upon the splenic flexure of the colon and the phreno-colic ligament.
Anterior Border (margo anterior) is between the gastric surface (facies
gastrica) and the diaphragmatic surface (facies diaphragmatica), it
is always notched.
Posterior Border (margo posterior) is between the diaphragmatic surface
(facies diaphragmatica) and renal surface (facies renalis). When it
is present, the basal surface (facies colica), at the lower end of the
spleen, is separated from the diaphragmatic surface (facies diaphrag-
matica) by the inferior border (margo inferior), from the gastric
surface (facies gastrica) by the anterior intermediate border (margo
intermedius anterior, and from the renal surface (facies renalis) by
the posterior intermediate border (margo intermedius posterior).
Structure of the Spleen. A fibre-elastic capsule, the tunica propria,
forms the framework of the spleen. It invests the organ externally, is
STRUCTURES OF THE SPLEEN 349
reflected inward at the hilum along the vessels, and gives off from both
parts bands or trabeculce lienis, which traverse the organ in all directions
and unite with each other, to form a sponge-like structure, having numer-
ous primary spaces or areola, in which the pulp is contained. The splenic
pulp (pulpa lienis) looks like a soft, dark-red mass, resembling grumous
blood, but consists of branching connective-tissue corpuscles, the support-
ing susientacular or reticular cells, which form a delicate reticulated
tissue, making within the areolrc a number of secondary spaces, in which is
blood containing a large proportion of whiteblood-corpuscles, also red
blood-corpuscles in all stages of disintegration. These secondary spaces
are continuous with the terminal arterial capillaries and the primary
venous radicles, both of which open into them, bringing the blood supply
into relation with the pulp elements. The connective-tissue coat of the
arteries is converted into a lymphoid tissue in the arterioles, and this tissue
presents thickenings of spheroidal shape, the — •
Malpighian Bodies (noduli lymphatici lienalis), — vary from Hoo to
^5 inch in diameter, and are attached to the arterioles of the organ in
groups of 6 or 8. Their reticulum is slender and open, densely filled
with lymphoid cells (leukocytes and spleen phagocytes), and well
supplied with capillaries.
Peritoneal, or Serous Coat (tunica serosa), — covers the whole organ,
except at the hilum and the attachments of the suspensory ligament
and the gastro-splenic omentum.
Splenic Artery (a. lienalis), — is large and tortuous, and divides at the
hilum into 5 or 6 branches (4), each supplying a segment of the organ,
and terminating in capillaries which open into the secondary spaces.
Veins, — arise by radicles from the secondary spaces, and anastomose
freely, joining to form 6 or more branches (5) which emerge from the
hilum and unite into the splenic vein (v. lienalis), the largest of the
constituents forming the portal vein.
Lymphatics, — are superficial and deep; the two sets joining in the inte-
rior of the organ, pass through the lymphatic glands at the hilum, and
terminate in the thoracic duct.
Nerves, — are branches of the splenic plexus (plexus lienalis), which is
formed by branches from the cceliac plexus, the left semilunar gan-
glion (ganglion coeliacum sinistrum), and the right pneumogastric
nerve (n. vagus dexter).
2. Coccygeal Gland or Body (glomus coccygeum) is a minute, highly
vascular, grayish-red, spherical body capping the terminations of the middle
sacral blood-vessels which form its stalk. It is situated in the mid-line
just beyond the tip of the coccyx, under cover of the coccygeal attachment
350 HUMAN ANATOMY
of the sphincter ani muscle in the small triangular interval between the
levator ani muscles. It is invested by a fibrous capsule which sends septa
into its substance dividing it up into follicles or nodules. The follicles
are masses of epithelial cells none of which are susceptible of staining by
chromium salts. Each follicle is traversed by a blood space or sinus
which affords free intercommunication between the arteries and veins of
the gland.
Nerve supply is by many minute fibres from the sympathetic. It is
not uncommon to find several accessory coccygeal glands which in all es-
sentials resemble the principal gland.
3. Pineal Gland or Body (epiphysis or corpus pineale) while classed
as a ductless gland, is probably not functional in man (see page 194).
4. Lymphoglandulse, the lymph glands, hcemal lymph glands, and hcemal
glands are described under the lymphatic system (see page 172).
ORGANS OF VOICE AND RESPIRATION
THE LARYNX
.The Larynx is a musculo-membranous-cartilaginous box, the essential
organ of voice, placed at the upper end of the air-passage, between the
trachea and the base of the tongue, in the upper and fore part of the neck,
where it forms a projection in the middle line. Its cartilages are 9 in num-
ber, 3 single and 3 in pairs, the — •
Thyroid Cartilage (cartilage thyreoidea). ;
Cricoid Cartilage (cartilago cricoidea).
Epiglottis (cartilago epiglottica).
Arytenoid Cartilages 2 (cartilagines arytaenoideae).
Cuneiform Cartilages 2 (cartilagines cuneiformes).
Cornicula Laryngis 2 (cartilagines corniculatae).
The Thyroid Cartilage (cartilago thyreoidea), or shield-like cartilage,
consists of two Alee or wings (&), united in front at an acute angle, the
highest portion of its front being called the Pomum Adami, Adam's apple
(prominentia laryngea). Its —
Outer Surface, — affords attachment to the sterno- thyroid (m. sterno-
thyreoideus) thyro-hyoid (m. thyreo-hyoideus) and inferior con-
strictor muscles; the first two being attached along its oblique ridge.
Upper Border, — is curved irregularly, has the thyroid notch (incisura
thyreoidea superior) (d) in front, and gives attachment to the thyro-
hyoid membrane.
THE LARYNX
351
Lower Border, — gives attachment to the crico-thyroid membrane in the
median line and on each side to the crico-thyroid muscle.
Inner Surface, — gives attachment to the true and false vocal cords, the
epiglottis, thyro-arytenoid and thyro-epiglottidean muscles, and the
thyro-epiglottidean ligament.
Posterior Border, — of each wing ends above and below in cornua (horns),
and gives attachment to the stylo- and palato-pharyngeus muscles.
Superior Cornu (cornu superius) (a) — of each side
affords attachment to the thyro-hyoid ligament.
Inferior Cornu (cornu inferius) (c] — of each side
articulates with the cricoid cartilage by a small
oval facet.
PIG. 119.
PIG. 1 20.
The Cricoid Cartilage (cartilago cricoidea), so
called from its ring-like shape, is situated below the
thyroid, with its narrow part to the front. It has
on each side 2 articular facets, one on the upper margin posteriorly for
the arytenoid cartilage, and one near the lower margin for the inferior
cornu of the thyroid cartilage. Its —
Posterior Portion (lamina cartilaginis cricoideae), — is deep and broad,
gives attachment in the middle line to the longi-
tudinal fibres of the oesophagus, and on each side to
the crico-arytenoideus posticus muscle (m. crico-ary-
taenoideus posterior).
Anterior Portion (arcus cartilaginis cricoideae), — is
narrow and convex, and affords attachment to the
crico-thyroid muscles and part of the inferior con-
strictor.
Upper Border, — affords attachment to the crico-thyroid membrane and
the crico-arytenoidei laterales muscles (mm. crico-arytaenoidei later-
ales), and articulates with the arytenoid cartilages.
Lower Border, — is connected to the upper ring of the trachea by fibrous
membrane.
The Arytenoid Cartilages (cartilagines arytaenoideae), or pitcher-like
cartilages, are 2 in number, pyramidal-shaped, and situated on the upper
margin of the cricoid cartilage posteriorly, closing in the back of the
larynx. Each cartilage has 3 surfaces, 2 angles, a base and an apex. The —
Anterior Surface, — gives attachment to the plica ventricular is or false
vocal cord, and the thyro-arytenoideus muscle (m. thyreo-arytae-
noideus).
Anterior Angle, — gives attachment to the plica vacates or true vocal
cord and the thyro-arytenoideus muscle (m. thyreo-arytaenoideus).
352
HUMAN ANATOMY
PIG. 121.
Posterior Surface, — has attached to it the arytaenoideus (m. arytae-
noideus).
Posterior Angle, — gives attachment to the crico-arytenoideus lateralis
and posticus muscles (mm. crico-arytaenoidei laterales et posterior).
Internal Surfaces of each — look toward each other.
Base, — has a facet for articulation with the cricoid.
Apex, — articulates with the corniculum laryngis.
The Cornicula Laryngis (cartilagines corniculatae) are 2
small cartilaginous nodules attached to the apices of the
arytenoid cartilages, and are also called the Cartilages of Santorini. To
them are attached the aryteno-epiglottidean folds (plicae arytaeno-
epiglotticae).
The Cuneiform Cartilages, or Cartilages of Wrisberg (cartilagines cunei-
formes), are 2 rods of yellow elastic cartilage contained in the free borders
of the aryteno-epiglottidean folds (plicaa arytaeno-epiglotticee) one on
each side, just in front of the arytenoid cartilages.
The Epiglottis (cartilage epiglottica) is a cartilaginous lid for the larynx.
It is leaf-shaped, situated behind the base of the tongue, and attached by
its apex to the posterior surface of the thyroid cartilage, just below the
median notch. Its —
Base, — is free, and curves over the base of
the tongue.
Apex, (petiolus epiglottidis), — is connected
to the receding angle of the thyroid car-
tilage by the thyro-epiglottic ligament.
Anterior Surface, — is attached to the hyoid
bone by the hyo-epiglottic ligament, and
to the tongue by 3 glosso-epiglottidean
folds (plicae glosso-epiglotticae).
Posterior Surface, — covers the superior aper-
ture of the larynx when food passes
through the pharynx.
Lateral Margins, — are connected to the ary-
tenoid cartilages by the aryteno-epiglotti-
dean folds (plicae arytaano-epiglotticse).
Ligaments of the Larynx are 20 in num-
ber,— 8 Extrinsic Ligaments, connecting the larynx to the hyoid bone
(i), the tongue, and the trachea (15); and 12 Intrinsic Ligaments, bind-
ing its several cartilages together. The Extrinsic Ligaments 8 are the —
Hyo-epiglottic Ligament, — connecting the hyoid bone (i) with the
epiglottis (2),
FIG. 122.
THE LARYNX 353
Glosso-epiglottic Folds three (plicae glosso-epiglotticae), — from the tongue
to the epiglottis.
Thyro-hyoid Membrane (membranahyo-thyreoidea) (3), — connecting the
thyroid cartilage (n) with the hyoid bone (i), and bounded laterally
by the two —
Lateral Thyro-hyoid Ligaments (ligamenta hyo-thyreoidea laterales)
(6) — each containing a nodule of cartilage, the cartilago triticea.
Crico-tracheal Ligament, — from the cricoid cartilage (18) to the trachea.
Intrinsic Ligaments 12, are the —
Thyro-epiglottic Ligament (ligamentum thyreo-epiglotticum), — connect-
ing the thyroid cartilage (u) with the epiglottis (2).
Crico-thyroid Membrane (conus elasticus) (13), — connecting the cricoid
(18) and thyroid (n) cartilages.
Crico-thyroid Capsular Ligaments 2, — enclosing those articulations.
Crico-arytenoid Ligaments (ligamenta cricoarytaenoidea) 2, — connect the
cricoid and arytenoid cartilages together.
Crico-arytenoid Capsular Ligaments 2, — enclosing those articulations.
Superior Thyro-arytenoid or Thyreo-arytenoid Ligaments 2, — in the false
vocal cords (plicae ventriculares) (5).
Inferior Thyro-arytenoid or Thyreo-arytanoid Ligaments 2, — in the true
vocal cords (plicae vocales) (9).
Interior of the Larynx presents a cavity which is divided into two parts
by the inward projection of the true vocal cords. The superior part,
sometimes called the vestibule, is broad and triangular in shape; the inferior
part of the cavity is at first elliptical and lower down is circular, becoming
continuous with the tube of the trachea. The —
Glottis or Rima Glottidis, — is a narrow chink or interval between the
inferior vocal cords, formed by the projection into the cavity of the
larynx of these cords and the thyro-arytenoidei muscles. Its greatest
length is less than an inch, its greatest breadth about half an inch. Its
form is a narrow fissure of varying width.
Superior or False Vocal Cords (plicae ventriculares) (5), — contain the
superior thyro-arytenoid ligaments, extend from the angle of the
thyroid cartilage around to the anterior surfaces of the arytenoids, and
consist of two folds of mucous membrane, each having a free cres-
centic margin.
Inferior or True Vocal Cords (plicae vocales) (9), — contain the inferior
thyro-arytenoid ligaments, extend from the angle of the thyroid car-
tilage around to the anterior angles of the bases of the arytenoids, and
consist of two thin layers of mucous membrane covering the ligaments
23
354 HUMAN ANATOMY
named, each having the thyro-arytenoideus muscle external and par
allel to it.
Ventricle of the Larynx (ventriculus laryngis) (7), — is an oblong fossa
on each side of the larynx, between the true and false vocal cords,
leading up to the sacculus laryngis by a narrow opening.
Sacculus Laryngis (appendix ventricuke) or Laryngeal Pouch, — is a
membranous sac, placed between the superior vocal cord and the
thyroid cartilage. It is of conical shape, and contains 60 or 70 small
mucous glands which secrete a fluid for the lubrication of the true
vocal cord. The sacculus is covered in by the aryteno-epiglottideus
inferior muscle internally, and by the thyro-epiglottideus externally,
both muscles compressing it to discharge its contents. The Sacculus
Laryngis is also called the Sinus of Morgagni, and the lower part of
the ventricle is sometimes named the Sac of Hilton.
Epithelium, — is stratified squamous epithelium over the true vocal cords,
the upper part of the aryteno-epiglottidean folds, and the upper half
of the posterior surface of the epiglottis; over all the rest of the larynx,
the lining mucous membrane is covered by columnar ciliated cells.
Muscles of the Larynx are 8 in number, 5 of which are the muscles of
the vocal cords and rima glottidis, and 3 are connected with the epiglottis.
The former are the —
Crico-thyroid (m. crico-thyreoideus).
Crico-arytenoideus Posticus (m. crico-arytaenoideus posterior).
Crico-arytenoideus Lateralis (m. crico-arytaenoideus lateralis).
Arytenoideus (m. arytaenoideus) .
Thyro-arytenoideus (m. thyreo-arytaenoideus).
Muscles of the Epiglottis are the — •
Thyro-epiglottideus (m. thyreo-epiglottideus).
Aryteno-epiglottideus (arytaeno-epiglottideus) Superior and Inferior.
These muscles are described at page 85.
Vessels of the Larynx. The Arteries are the Superior Laryngeal and
Crico-thyroid branches of the superior thyroid (a. thyreoidea Superior)
from the external carotid: and the Inferior Laryngeal Branch of the infe-
rior thyroid (a. thyreoidea inferior) from the thyroid axis (truncus thy-
reocervicalis). The —
Veins, — open into the internal jugular and the innominate vein.
Lymphatics, — open into glands near the bifurcation of the common caro-
tid artery, and others in front of the crico-thyroid membrane.
Nerves of the Larynx are the Superior and Recurrent (inferior) Laryn-
geal branches of the pneumogastric (n. vagus), joined by filaments from the
spinal accessory (n. accessorius) and the sympathetic. The — •
THE TRACHEA AND BRONCHI 355
Superior Laryngeal, — is the nerve of sensation. It enters the larynx by a
hole" in the thyro-hyoid membrane, and supplies the mucous mem-
brane, and the crico-thyroid and arytenoideus muscles. It has the
following branches, namely—
External Laryngeal. Internal Laryngeal.
Recurrent Laryngeal (n. laryngeus inferior), — is the motor nerve. It
winds from before backwards, around the subclavian artery on the
right side, around the arch of the aorta on the left side, and is dis-
tributed to all the laryngeal muscles except the crico-thyroid and
arytenoideus giving off, in its course, cardiac, oesophageal, tracheal,
and pharyngeal filaments, and finally anastomosing with the superior
laryngeal nerve.
THE TRACHEA AND BRONCHI
The Trachea is a membrano-cartilaginous, cylindrical tube, about 4%
inches long, and % to i inch in diameter, beginning at the lower border
of the larynx, opposite the 6th cervical vertebra, and ending opposite the
upper border of the 5th thoracic, by its bifurcation into the two bronchi.
It is composed of a fibro-elastic membrane containing 16 to 20 imperfect
cartilaginous rings, connected by muscular fibres. It is lined with mucous
membrane covered with ciliated columnar epithelium, and furnished with
racemose glands, the tracheal glands.
Anteriorly, — it is convex, and is covered from above downward by the —
Isthmus of the Thyreoid Gland. Thymus Gland.
Inferior Thyreoid Veins. Arch of the Aorta.
Sterno-hyoid Muscle. Left Innominate Vein.
Sterno-Thyreoid Muscle. Innominate Artery.
Cervical Fascia. Left Carotid Artery.
Manubrium of the Sternum. Deep Cardiac Plexus.
Posteriorly, — it is flat, and in relation with the oesophagus.
Laterally , — it is in relation with the—
Common Carotid Arteries. Recurrent or Inferior Laryngeal Nerves.
Thyreoid Gland, lateral lobes. Pleurae.
Inferior Thyreoid Arteries. Pneumogastric or Vagus Nerves.
The Bronchi are two tubes similar in formation to the trachea, extending
from its bifurcation into the lungs, where they divide and subdivide into
bronchial tubes (rami bronchiales), losing their rings at the 2d or 3d sub-
division, whence plates of cartilage extend in their walls to their minuter
ramifications. The —
356 HUMAN ANATOMY
Right Bronchus (bronchus dexter), — the wider, and the more hori-
zontal, is about i inch long, has 6 to 8 rings, and divides into 2 main
divisions, the eparterial branch, to the upper lobe, given off above the
pulmonary artery, and the hyparterial branch, passing under the artery
to be divided into two branches, for the middle and lower lobes. The
right bronchus lies behind the vena cava superior and the right auricle
of the heart having the right pulmonary artery at first below, then
anterior to it, and the vena azygos major arching over it from behind
forward.
Left Bronchus, — the narrower and more oblique, is nearly 2 inches long,
Has 9 to 12 rings, and divides into 3 main divisions (though its lung
has but 2 lobes). It passes beneath the arch of the aorta and in front
of its descending portion, also in front of the oesophagus and the tho-
racic duct, having the left pulmonary artery above and in front of it.
Vessels and Nerves. The Arteries are the Tracheal, branches of the
inferior thyreoid, from the thyreoid axis (truncus thyreocervicalis) ; and
the Bronchial, from the thoracic aorta. The — •
Veins, — open into the thyreoid plexus and the bronchial veins.
Lymphatics, — terminate in the mediastinal glands.
Nerves, — are derived from the pneumogastric (n. vagus) and its recur-
rent or inferior laryngeal branch, also from the sympathetic.
THE PLEURA
The Pleurae are two delicate serous sacs, one surrounding each lung,
and reflected over the pericardium, the diaphragm, and the inner surface
of the thorax. The right sac is shorter, wider, and reaches higher into the
neck than the left. The two sacs meet for a short space behind the middle
of the sternum, at the approximation of the anterior borders of the lungs.
The—
Pleura Pulmonalis, or Visceral Layer, — covers the lung, and invests that
organ as far as its root.
Pleura Costalis, or Parietal Layer, — lines the inner surface of the parie-
tes of the chest.
Cavity of the Pleura, — is the space between the two layers.
Ligamentum Latum Pulmonis, or Broad Ligament of the Lung, — is a
triangular fold or reflection of pleura, which descends from the root
of the lung posteriorly to the upper surface of the diaphragm.
The Mediastinum is the space between the two pleurae in the median
line of the thorax, extending from the sternum to the vertebral column,
and containing all the thoracic viscera except the lungs. The —
THE LUNGS 357
Superior Mediastinum, — lies above the upper level of the pericardium
and contains the —
Origins of the Sterno-hyoid and Sterno-thyreoid Muscles.
Longus Colli Muscles, their lower Pneumogastric Nerve (n. vagus).
ends. Cardiac and Phrenic Nerves.
Arch of the Aorta. Left Recurrent or Inferior Laryn-
Innominate Artery. geal Nerve.
Left Carotid Artery, in part. Trachea.
Left Subclavian Artery, in part. (Esophagus.
Superior Vena Cava, upper half. Thoracic Duct.
Innominate Veins. Thymus Gland.
Left Superior Intercostal Vein. Lymphatic Glands.
Anterior Mediastinum, — between the sternum and the pericardium, con-
tains—
Areolar Tissue. Branches of Internal Mammary Artery.
Triangularis Sterni Muscle. Lymphatic Vessels and Glands.
Middle Mediastinum, — contains the — •
Heart and Pericardium. Bifurcation of the Trachea.
Ascending Aorta. Pulmonary Arteries and Veins.
Superior Vena Cava, lower half. Phrenic Nerves. Lymphatic Glands.
Posterior Mediastinum, — contains the —
Descending Aorta. (Esophagus.
Azygos Veins. Thoracic Duct.
Pneumogastric (nn. vagi) and Splanchnic Lymphatic Glands.
Nerves.
THE LUNGS (PULMONES)
The Lungs are the two essential organs of respiration contained in the
cavity of the thorax, where they are separated from each other by the
heart (i) and the other contents of the mediastinum. They are covered
by the pleurae, and are characterized by lightness (sp. gr. 0.345 to 0.746),
sponginess, elasticity, and crepitation when pressed. They weigh together
about 42 ounces, the right lung being the heavier by about 2 ounces. At
birth their color is a pinkish-white, becoming mottled as age advances by
slate-colored patches, from the deposit of carbonaceous granules in the
areolar tissue of the organ. The. Right Lung is the larger and has^3 lobes;
the Left Lung has 2 lobes. Each lung presents for examination an —
Apex (apex pulmonis), — situated in the neck, behind the interval be-
tween the two heads of the sterno-mastoid muscle, and rising about
35«
HUMAN ANATOMY
an inch above the clavicle. It is in relation with the subclavian artery
and the scaleni muscles.
Base (basis pulmonis), — is broad, concave, and directed obliquely down-
ward and backward, resting on the upper convex surface of the dia-
phragm.
External Surface (facies costalis), — is convex, smooth, marked by the
fissures, and corresponds in form to that of the thorax.
Inner Surface (facies mediastinalis), — is concave, presents in front a
depression for the heart and behind a deep fissure, the hilum, which
gives attachment to the root of the lung.
FIG. 123.
Root (radix pulmonis), — is where the bronchus (18), vessels (20), and
nerves enter the lung, bound together by areolar tissue. In front of
the root is the phrenic nerve, behind it the pneumogastric nerve (n.
vagus). Its chief structures are arranged in the following manner: —
(Pulmonary veins.
Pulmonary artery.
From above downward, on
right side of body,
Bronchus, etc.
Bronchus (18), etc.
Pulmonary artery.
Pulmonary veins (20).
V. A. B.
B. A. V.
THE LUNGS
359
From above downward, on
left side of body,
Pulmonary artery (7).
Bronchus (19), etc.
Pulmonary veins (20).
A. B. V.
FIG. 124.
Structure of the Lung. The lung has a serous coat (the pleura); a
sub-serous, elastic areolar tissue, investing the entire organ, and extending
inward between the lobules; and the
parenchyma, or true lung-tissue, com-
posed of —
Lobules, — each consisting of several
air-cells or compartments, arranged
around the termination of a bron-
chiole, and surrounded by 6 plexuses
of pulmonary and bronchial arteries
and veins, lymphatics and nerves.
Each lobule is a miniature lung,
pyramidal in form, with base out-
ward, and about ^f 2 inch in diam-
eter. Fig. 123 shows 2 lobules.
Alveoli, or Air-cells, — are separated
from each other by thin septa, are
lined with pavement epithelium on
a basement membrane, and vary
in diameter from ^Oo to Ko inch.
Vessels and Nerves of the Lungs. The lungs are nourished by the
bronchial arteries, and supplied with blood for oxygenation by the pul-
monary arteries.
Bronchial Arteries, — are derived from the thoracic aorta.
Bronchial Veins, — open on the right side into the vena azygos major,
on the left side into the superior intercostal vein.
Pulmonary Arteries (5, 6, 7), — are derived from the right heart. Their
terminal (lobular) branches do not anastomose with each other.
Pulmonary Veins (20), — open by 4 large orifices into the left auricle of
the heart, carrying oxygenated blood from the lungs to the left heart.
The veins anastomose freely.
Lymphatics, — terminate in the bronchial glands, at the root of the lung.
Nerves, — are branches from the vagus and the sympathetic forming
the anterior and posterior pulmonary plexuses, from which filaments
are distributed to each lobule.
360 HUMAN ANATOMY
THE URINARY ORGANS
THE KIDNEYS (RENES)
The Kidneys (renes) are two organs, situated in the back part of the
abdominal cavity, one on each side of the vertebral column, behind the
peritoneum, extending from the nth and i2th ribs to within 2 inches of
the crest of the ileum, the^ right kidney being a little lower than the left
one. Each kidney is about 4 inches by 2 by i, in the male adult weighs
from 4)^ to 6 oz.; and presents on its inner concave border the —
U.ilum, — a fissure leading into the sinus or cavity of the organ, and per-
mitting the passage of the vessels, nerves, and ureter, arranged in the
following order, from before backward, the renal vein, renal artery,
ureter, ^VAU.
Relations of the Kidneys. They are partially covered by peritoneum
on their anterior surface, but not at all posteriorly. They are surrounded
by a mass of fat and areolar tissue, and have the following relations: —
Anterior Surface (facies renis anterior) of the Right Kidney, — is in rela-
tion with the supra-renal gland, the right lobe of the liver, the de-
scending duodenum, and the ascending colon.
Anterior Surface of the Left Kidney, — with the supra-renal gland, the
stomach, the tail of the pancreas, the descending colon, the jejunum,
and part of the spleen.
Posterior Surface (facies renis posterior), — with the crus of the dia-
phragm, 1 2th rib and the transverse processes of the upper three
lumbar vertebrae, psoas magnus, quadiatus lumborum, and the apo-
neurosis of the transversalis muscle.
Upper Extremity (extremitas superior), — is capped by the supra-renal
capsule (i).
Lower Extremity (extremitas inferior), — extends to within 2 inches of
the crest of the ilium.
jGr.eneral Structure of the Kidney. A vertical section from its convex
to its concave border, shows it to consist of a central cavity QTsinuSj sur-
rounded except on one side by the kidney substance proper (parenchyma) .
The latter is divided into a cortical portion externally, and a medullary
portion internally, the medullary being arranged in pyramidal masses,
whose apices project into the central cavity. A dense, fibrous capsule
(tunica fibrosa) invests the organ, and is reflected inward at the hilum,
lining the sinus and forming sheaths for the vessels. It gives off an inter-
stitial stroma of connective tissue, which binds the vessels and tubes firmly
together throughout the substance of the kidney. The —
THE KIDNEY 361
Cynical Portion, — consists of uriniferous tubules (tubuli renales). Mal-
pighian bodies (glomerula or renal corpuscles), blood-vessels, nerves,
lymphatics, connective tissue, and a granular matrix. It is of a red
p color, and is prolonged down between
the pyramids, to the sinus; the prolon-
gations being named columns of Berlin
(columnae renales) and the portions over
the bases of the pyramids are the cortical
arches.
Medullary .Substance (3), — contains chiefly
the straight, collecting portion of the
uriniferous tubules, arranged in pyram-
idal masses, the pyramids of Malpighi
(pyramides renales), the apices of which
project into the sinus.
Sinus, — receives the pelvis (6) of the ureter
(7), and is divided into 3 infundibula (5),
and they into 7 to 13 calices, into which
open the orifices of the uriniferous tubules,
1000 on each papilla or apex of a pyramid.
Minute Structure of the Kidney commences in the cortical substance
of the organ as the Malpighian bodies (corpuscula renis), small round
masses of deep-red color, averaging about K20
inch in diameter, and each consisting of a central
glomerulus of vessels and a membranous envelope
(capsula glomeruli) or Bowman's capsule, the
latter being the commencement of a uriniferous
tubule. The—
Malpighian. Tuft, — or vascular glomerulus, is a
network of convoluted capillary blood-vessels,
beginning by the afferent vessel and ending in
the eferent vessel, which are the respective
radicles of some of the branches of the renal
artery (a) and the renal vein (»). The affer-
ent vessels are usually the larger.
Bowman's Capsule (capsula glomeruli) (c), —
surrounding the glomerulus, is the dilated
extremity of a uriniferous tubule (d), and is lined on its inner surface
by a layer of j>quamous epithelial cells, on a delicate supporting
membrane, closely surrounding the convolutions of the glomerulus
and dipping in between them.
362 HUMAN ANATOMY
The Tubuli Renales, or Uriniferous Tubules, begin at the capsule of
Bowman in the Malpighian bodies, and open into the sinus of the kidney
by orifices on the surface of the papillae. During their course they leave
the cortical portion, enter the medullary portion, return to the cortical
and again to the medullary, in which they continue to their termination.
In their course they become first convoluted, then spiral, then looped,
again spiral and convoluted, curved and finally straight; and have received
the following names: — •
Proximal Convoluted Tube, — the first portion, below the neck at Bow-
man's capsule, in the cortical zone. Epithelium lining the tube is
polyhedral and of striated appearance.
Spiral Tube of Schachowa, — in the cortical zone. Epithelium polyhedral
and striated.
Henle's Loop, — in the medullary zone, consists of a descending limb, a
loop, and an ascending limb, the latter becoming spiral- as it ascends
into the cortical zone. Epithelium flat in the descending limb, poly-
hedral and striated in the ascending one.
Irregular Tubule, — in the cortical zone. Epithelium angular and stri-
ated.
Distal Convoluted Tubule, — in the cortical zone. Epithelium polyhedral.
Curved Tube, — in the cortical zone. Epithelium varied, angular,
spindle-shaped, polyhedral.
Straight or Collecting Tube, — partly in the cortical zone, descends
through the medullary portion and joins with others, forming the
pyramids of Fcrrein (apices outward) in the cortical zone, and the
pyramids of Malpighi (apices inward) in the medullary substance.
Epithelium more or less columnar.
Connective Tissue or Stroma, — binds the tubules firmly together.
Arteries of the Kidney arise from the renal artery, a large branch of
the abdominal aorta. It divides into 4 or 5 branches, which enter the
kidney at the hilum (hilus renis), giving off small branches to the supra-
renal capsules, the ureter, etc. These again divide and end in the —
Arteries Pro price Renales, — the renal arteries proper, which enter the
kidney substance in the columns of Bertin (see page 360), form arterial
arches over the bases of the pyramids, and divide into ascending and
descending branches. The —
Ascending or Interlobular Branches, — pass to the capsule and end in the
capillary network of that part of the cortex, giving off in their course
the afferent vessels to the Malpighian tufts (see page 360).
Descending or Arteriolce Reclce, — supply the medullary pyramids and
end at their apices in the venous plexuses there situated.
'
THE URETERS 363
Veins of the Kidney arise from 3 sources, — the stellate veins beneath
t he i -upside of the organ, the venous radicles in the Malpighian tufts, and
the venous plexuses at the apices of the pyramids of Malpighi. Those
from the stellate plexuses on the surface of the kidney join together, form-
ing the —
Interlobular Veins, — which pass inward between the pyramids of Ferrein,
receive branches from the plexuses on the convoluted urinif erous tubes,
and join with the vence recta from the apices of the pyramids of Mal-
pighi, to form the — •
Vence Propice Renales, — the renal veins proper, accompany the arteries
of the same name, receive the efferent vessels from the Malpighian
bodies adjacent, and join with corresponding veins in the sinus to
form the —
Renal Vein, — emerges at the hilum and opens into the Jnferior vena
cava; the left vein being longer than the right, having to cross in front
of the abdominal aorta.
Nerves of the Kidney are derived from the renal plexus, which is
formed by branches from the solar plexus (plexus cceliacum), the aortic
plexus, the semilunar ganglion, and the lessei and smallest splanchnic
nerves. They have small ganglia upon them, and communicate with the
spermatic plexus.
Lymphatics consist of a superficial and a deep set, and terminate in the
lumbar glands.
THE URETERS
The Ureter, the excretory duct of the kidney, is a musculo-membranous
tube, which conducts the urine from the kidney to the bladder. It com-
mences within the sinus of the kidney by 7 to 13 short tubes or calices,
which encircle the apices of the pyramids of Malpighi, and converge into
2 or 3 tubular divisions or infundibula, these by their junction forming the
pelvis or upper dilated extremity of the duct. The —
Ureter Proper, — begins at the lower end of its pelvis, is about 16 inches
long, and of the diameter of a small goose-quill. It descends, through
the lumbar region of the abdomen and the pelvic cavity, to the base
of the bladder, and opens into the cavity of that organ about 2 inches
from its fellow.
Course of the Ureter. In its course the ureter passes obliquely down-
ward and inward through the lumbar region, and downward, inward and
forward through the pelvic cavity, enters the posterior false ligament of
the bladder, passes obliquely between the muscular and mucous coats of
364 HUMAN ANATOMY
that organ for nearly an inch, and ends by a constricted orifice at one of
the posterior angles of the trigone at the base of the bladder.
Relations of the Ureter. The junction of the renal pelvis and the
ureter proper is opposite the spinous process of the first lumbar vertebra,
about 2 inches from the middle line of the back. The ureter lies upon the
psoas muscle and behind the peritoneum; behind the ileum on the right
side and the sigmoid flexure of the colon on the left side. It crosses the
common or the external iliac artery; and is crossed by the spermatic vessels,
and the branches of the mesenteric arteries, also by the vas deferens in the
male. The right ureter lies close to the outer side of the inferior vena
cava. In the female the ureters pass along the sides of the neck of the
uterus and the upper part of the vagina, and beneath the root of the broad
ligament.
Structure of the Ureter. It is composed of 3 coats, — fibrous, muscular,
and mucous. The fibrous coat (tunica adventitia) is continuous with the
capsule of the kidney and with the fibrous structure of the bladder. The —
Muscular Coat (tunica muscularis), — consists of longitudinal fibres ex-
ternally (stratum externum), and circular fibres internally (stratum
medium). A third layer (stratum internum), consisting of longi-
tudinal fibres, is found internal to the circular layer, in the neighbor-
hood of the bladder.
Mucous Coat, — is prolonged over the papillae of the kidney, and is con-
tinuous with the mucous lining of the bladder. Its epithelium re-
sembles that of the bladder, and is known as' 'transitional epithelium,
consisting of 3 layers of cells, the innermost of which are quadrilateral
in shape.
Vessels and Nerves. The Arteries of the ureter are branches from the
renal, spermatic, internal iliac, and inferior vesical. The Nerves are de-
rived from the inferior mesenteric, spermatic, and pelvic plexuses.
THE SUPRA-RENAL GLANDS OR CAPSULES (GLANDULE
SUPRARENALES)
The Supra-renal Glands are properly classed with the ductless glands
of. the chromaphiL^and cortical systems (see page 344). They are two
small, yellowish bodies, situated one above each kidney, behind the perit-
oneum, and in the posterior portion of the abdomen. They vary in size
in different individuals, but are usually i^ inches long and wide, and from
2 to 3 lines in thickness. Each capsule has a small furrow, the hilum, on
its anterior surface, in which the vessels enter the organ, and in structure
consists of a —
THE BLADDER 365
Fibrous Capsule, — which is very thin, closely adherent, and sends numer-
ous septa inward.
Cortical Substance, — composed of columnar masses of polyhedral cells,
held together in layers by a fibrous stroma.
Medullary Substance, — is darker than the cortical portion, and pulpy.
It consists of granular cells, supported by a delicate stroma, and
believed by some anatomists to be prolonged into the nerve fibres of
a very intricate plexus.
Relations of the Supra-renal Glands. Their surface is surrounded by
ireolar tissue containing much fat; their bases rest on the upper front
parts of the kidneys, theiVgpsterior surfaces on the crura of the diaphragm,
about the level of the loth thoracic vertebra. The —
A nterior Surface, — of the right gland is covered by the liver; that of the
Ic-ft one by the spleen and pancreas.
Superior Surface, — of each is in relation internally with the great splanch-
nic nerve and semilunar ganglion.
Vessels and Nerves. The Arteries are the Supra-renal branches of the
aorta, renal, and phrenic arteries, forming a dense capillary plexus in the
cortical portion of the organ.
Veins, — of each open into a single trunk, the Supra-renal Vein, which
on the right side of the body empties into the inferior vena cava, on
the left side into the left renal vein.
Lymphatics, — open into the lumbar glands.
Nerves, — are derived from the solar (cceliac) and renal plexuses, with
some filaments from the phrenic and vagus nerves, forming a compli-
cated network in the medullary substance of the organ, and having
numerous small ganglia developed upon them.
THE BLADDER (VESICA URINARIA)
The Bladder, the reservoir for the urine, is a musculo-membranous sac,
situated in the anterior portion of the pelvis, behind the. pubes, and in
front of the rectum in the male, in front of the cervix uteri and Vagina in
the female. When empty and contracted, or when slightly distended, it is
contained in the pelvic cavity; when greatly distended it is ovoid in shape,
and rises into the abdominal cavity, often extending nearly as high as the
umbilicus. When moderately distended it measures about 5 by 3 inches,
and holds about a pint. The —
Summit, — is connected to the umbilicus by the urachus (ligamentum
umbilicale medium) and the obliterated hypogastric arteries (liga-
366
HUMAN ANATOMY
FIG. 127.
menta umbilicales laterales) of the foetus, forming three fibrous cords,
the Superior Ligament of the bladder.
Superior or Abdominal Surface, — is free, and is covered by peritoneum.
Anterior or Pubic Surface, — is partly covered by peritoneum above, and
is in relation below with the internal obturator muscles, the recto-
vesical fascia, and the anterior true ligaments of the bladder.
Posterior Surface, — is covered by peritoneum, and is in relation with the
rectum in the male, with the uterus and upper part of the vagina in
the female.
Lateral Surfaces, — are partly covered by peritoneum behind and above;
each is crossed obliquely by the obliterated hypogastric artery and the
vas deferens (c), the first passing from
below forward, the latter from below
backward.
Fundus or Base, — is partly covered by
peritoneum, and rests on the second
portion of the rectum in the male, on
the lower part of the cervix uteri and
adherent to the anterior wall of the
vagina in the female.
Cervix or Neck, — is constricted and contin-
uous with the urethra (f). It is sur-
rounded in the male by the prostate
gland (h), and is directed downward
and forward.
Ligaments of the Bladder are 10 in num-
ber, of which 5 are true ligaments, and 5
formed by folds of peritoneum. The true ligaments are the —
Anterior or Pubo-prostatic, 2, — are formed by the recto-vesical fascia,
and extend from the neck of the bladder, over the prostate gland, to
the back of the pubic bone.
Lateral, 2, — also formed by the recto-vesical fascia, are attached to the
sides of the base of the bladder, and the prostate gland.
Urachus, — the superior ligament (ligamentum umbilicale medium),
connects the summit of the bladder with the umbilicus. It is the
obliterated remains of a canal, which in the embryo connects the
bladder with the allantois and is situated between the two obliter-
ated hypogastric arteries (ligamenta umbilicales laterales).
False Ligaments, folds of peritoneum, are the —
Posterior False Ligaments (plicae vesico-uterinae) female, (plicae recto-
vesicalis) male, 2, — pass from the postero-lateral parts of the bladder.
are false ligaments, being
THE BLADDER 367
to the sides of the rectum in the male, to the sides of the uterus in
the female.
Lateral False Ligaments (plicae umbilical es laterales), 2, — from the
iliac fossae and lateral walls of the pelvis to the sides of the bladder.
Superior, or Suspensory Ligament (plica umbilicalis media), — from the
summit of the bladder to the umbilicus, being peritoneum carried
off from the bladder by the urachus and the obliterated hypogastric
arteries.
Interior of the Bladder is lined by mucous membrane, which forms
folds or ruga when the viscus is empty, being loosely connected to the
muscular coat, except at the trigone and the uvula, where it is closely ad-
herent. The floor of the bladder presents the —
Trigonum Vesica, or Vesical Trigone (i, Fig. 127), — a pale-colored, tri-
angular space, extending from the urethral opening in front to a line
connecting the orifices of the ureters behind; and characterized by its
smooth surface and the intimate adhesion between its mucous and
muscular coats.
Uvula Vesicce (3, Fig. 127), — is a small elevation of mucous membrane
projecting from the floor of the bladder into the urethral orifice. It is
said to be lifted by the anterior fibres of the levator ani muscle.
Orifices of the Ureters (2, Fig. 127), — about 2 inches apart, at the base of
the trigone, and i ^ inches from the urethral opening.
Structure of the Bladder. The bladder has 4 coats, — serous or perit-
oneal, muscular, sub-mucous, and mucous. The peritoneal coat is a
partial one, investing only the superior and posterior surfaces, and the
upper portion of the lateral surfaces. The —
Muscular Coat, — consists of unstriped muscular fibres, arranged in 3
layers; an external layer, chiefly longitudinal, the so-called detrusor
urines muscle; a middle layer, mostly circular, and forming a sphincter
vesicfg around the neck; and an internal layer, chiefly longitudinal.
Muscles of the Ureters, — are two bands of oblique fibres, extending from
behind the orifices of the ureters to the middle lobe of the prostate
gland.
Sub-mucous Coat, — is a layer of areolar tissue, connecting the muscular
with the mucous coat.
Mucous Coat, — is thin, smooth, of a pale rose color, and is continuous
with the lining membrane of the ureters and the urethra. Its epithe-
lium is of the transitional variety, consisting of an inner layer of poly-
hedral, flattened, nucleated cells; beneath which are two layers of
club-shaped and spindle-shaped cells, wedged together. It contains
no mucous glands.
368 HUMAN ANATOMY
Vessels and Nerves. The Arteries of the bladder are the superior
middle, and inferior Vesical in the male, with additional branches from the
uterine and vaginal in the female; all from the anterior trunk of the internal
iliac. The—
Veins, — form a plexus around the neck, sides, and base of the bladder,
and terminate in the internal iliac vein.
Lymphatics, — terminate in the internal iliac glands.
Nerves, — are derived from the pelvic plexus to the upper part of the
organ, from the 3d and 4th sacral nerves to its base and neck.
THE MALE URETHRA
The Urethra is the urinary canal from the neck of the bladder to the
meat us urinarius; in the male it is chiefly within the penis, is from 8 to 9
inches in length, and is divided into three parts, — the pr astatic, membranous,
and spongy portions of the urethra.
The Prostatic Portion (pars prostatica) of the Urethra is that part of the
canal which pierces the prostate gland (4), is about i finches in length, of
spindle shape, and the widest and most dilatable part of the urethra. Its
floor presents the —
Verumontanum, or Caput Gallinaginis (colliculus seminalis) (6), — an
elevation of the mucous membrane (crista urethralis) and its adjacent
tissue, Y± inch long, and supposed to contain muscular and erectile
tissue.
Prostatic Sinus (7), — one on each side of the verumontanum, containing
the orifices of the prostatic ducts.
Sinus Pocularis, or Uterus Masculinus (utriculus prostaticus) (5), — is a
small cul-de-sac situated at the front part of the verumontanum.
It extends for ^ inch upward and backward into the prostate gland
beneath its middle lobe.
Orifices of the Ejaculatory Ducts (8), — open on the margins of the sinus
pocularis.
The Membranous Portion (pars membranacea) (9) is % inch long above,
and Yz inch along its floor, being that part of the canal lying between the
superior and inferior layers of the triangular ligament of the perinaeum.
Its walls are very thin, and almost destitute of erectile tissue. It is
surrounded by the deep transversus perinei or compressor urethras muscle,
and except the orifice, is the narrowest part of the urethral canal. On
its sides are the —
Ducts of Cowper's Bulbo-urethral Glands (n), — on their way to open
into the bulb of the urethra.
THE URETHRA
369
FIG. 128.
The Cavernous or Spongy Portion (pars cavernosa) (16) is about 6
inches long, and has two dilatations, one at each end, named respectively
the Bulb and the Fossa Navicularis. The —
Bulb' of the Urethra (13), — is the upper end of the cavernous portion,
projects backward for Y± inch, and contains the orifices (15) of the
ducts of the bulbo-urethral
or Cowper's glands.
Fossa Navicularis, — is the lower
dilatation of the urethra,
and is situated within the
glans penis.
Lacuna Magna (lacuna ure-
thralis of Morgagni), — the
largest of several orifices of
mucous follicles, situated on
the roof of the fossa navicu-
laris.
Glands of Littre (glandulae ure-
thrales), — are numerous mu-
cous glands and follicles,
opening into the urethral
canal, their orifices being
directed forwards.
Meatus Urinarius, — the exter-
nal orifice; is the most con-
tracted portion of the ure-
thra, and presents a vertical
slit, about 3 lines long,
bounded laterally by two
small labia.
Structure of the Urethra. — It is
composed of a continuous mucous
membrane, continuous with the
mucous lining of the bladder,
ureters, and kidneys, and pro-
longed into the ducts opening into the urethra. The mucous membrane
is supported by a submucous tissue, which connects it with the various
structures through which it passes. The —
Submucous Tissue, — consists of a vascular erectile layer, outside which is
a circular layer of unstriped muscular fibres.
Voluntary Muscles of the Urethra, — are the deep transversus perinei or
24 • .
37O HUMAN ANATOMY
compressor urethrae and the bulbo-cavernosus or accelerator urinae,
described on page 98.
Epithelium, — is of the columnar variety, except near the meatus where it
is squamous.
THE FEMALE URETHRA
The Urethra in the female is only about i ^ inches long, imbedded in the
anterior wall of the vagina, perforating the triangular ligament, and sur-
rounded by fibres of the deep transversus perinei or compressor urethras
muscle. Its diameter is about % inch, but it is capable of considerable
dilatation, being surrounded by softer structures than are those around
the male urethra. The —
Meatus Urinarius, — is situated directly in front of the vaginal opening
and about an inch behind the glans clitoridis.
ORGANS OF GENERATION
THE MALE ORGANS OF GENERATION
THE URETHRAL GLANDS
The Prostate Gland (prostata) is a musculo-glandular organ, which
surrounds the neck of the male bladder and the beginning of the male
urethra. It is situated in the pelvic cavity, behind the lower part of the
symphysis pubis, and above the deep layer of the triangular ligament, its
posterior surface resting on the rectum. It is perforated by the urethra
and the common seminal ducts, but its own ducts open into the prostatic
portion of the urethra. It measures about i% inches by i)^ inches by i
inch, weighs about % oz., resembles a horse-chestnut in size and shape,
and consists of three lobes, two being lateral and of equal size, the third or
middle lobe being a small prominence situated in the notch between the
lateral lobes. Its—
Position, — is maintained by the anterior or pubo-prostatic ligaments of
the bladder, the deep layer of the triangular ligament, and the anterior
portions of the levator ani muscles.
Structure, — is glandular substance arranged in follicular pouches, and
dense muscular tissue, the whole being invested by a firm fibrous
capsule, which gives off thin trabeculae into the substance of the gland.
Ducts, — are 1 2 to 20 in number, lined by columnar epithelium, and open
on the floor of the prostatic portion of the urethra.
Arteries, — are derived from the internal pudic, vesical and haemorrhoidai
arteries.
THE PENIS 371
Veins, — terminate in the internal iliac vein.
Nerves, — are branches from the pelvic or hypo-gastric plexus.
Cowper's Glands (glandulae bulbo-urethrales) are two small, rounded
bodies, about the size of peas, situated between the two layers of the
triangular ligament, one on each side of the membranous portion of the
urethra, close above the bulb, and enclosed by the transverse fibres of the
compressor urethrae muscle. The —
Excretory Duct, — of each gland opens by a minute orifice on the floor
of the bulbous part of the cavernous portion of the urethra, after tra-
versing the wall of the urethra for about i inch, beneath its mucous
coat.
THE PENIS
The Penis is composed of a mass of erectile tissue enclosed in three
cylindrical compartments, each surrounded by a fibrous sheath which is
prolonged inward, forming numerous bands or trabeculae, which divide
the compartments into a number of spaces. The compartments are the
two corpora cavernosa and the corpus spongiosum (corpus 5cavernosum
urethrae) (6), the latter lying between and beneath the former, like the
ramrod of a double-barreled gun. The —
Erectile Tissue, — is lodged in the interspaces between the trabeculae of
the fibrous structure, and consists of an intricate venous plexus,
supplied by afferent arteries and emptied by efferent veins.
The Corpora Cavernosa lie side by side, forming the upper and lateral
parts of the penis. They are joined together along their anterior three-
fourths, their posterior one-fourth forming the
Crura, which arise from the tuberosities of the
ischia and their rami, and meet beneath the sym-
physis pubis, forming two grooves, one above
for the dorsal vessels (i), and nerves (3), the in-
ferior one for the corpus spongiosum (6).
Suspensory Ligament (lig. suspensorium penis),
— a fibrous membrane which connects the
root of the organ to the symphysis pubis.
Septum Pectiniforme (5), — is the front portion
of the fibrous septum between the corpora cavernosa. This septum
extends but two-thirds along the penis, and is wanting for its anterior
third.
The Corpus Spongiosum (corpus cavernosum urethras) (6) is an erectile
tube lying in the inferior groove between the two corpora cavernosa,
having within it the urethra, and expanded at both ends to form the glans
372 HUMAN ANATOMY
penis and the bulb. It is composed of trabecular (band-like) structure,
derived from a fibrous sheath, and containing erectile tissue. The —
Bulb of the Corpus Spongiosum (bulbus urethras), — receives the urethra
and is surrounded by the (bulbo-cavernosus) or accelerator urinas
muscle.
Glans Penis, — is the external expansion of the corpus spongiosum
(corpus cavernosum urethras) and covers by its base the ends of the
two corpora cavernosa. Its base presents a rounded border, called
the corona glandis, behind which is a deep sulcus, the cervix (collum
glandis).
Glands of Tyson, — small lenticular sebaceous glands opening on the
corona and cervix of the glans, and secreting an odorous sebaceous
matter, the smegma.
Meatus Urinarius, — the external orifice of the urethra, is situated at the
summit of the glans penis.
Prepuce (praeputium), — a prolongation of the integument of the penis,
covering or partly covering the glans penis.
Franum Pmputii (fraenulum praeputii), — a fold of mucous membrane
lying along the raphe of the glans penis, and connecting the prepuce
with the glans.
Vessels and Nerves. The Arteries are branches of the internal pudic,
named as follows: the artery of the bulb, to the bulb of the corpus spongio-
sum; the arteries of the corpora cavernosa, to that structure; and the dorsal
artery of the penis, to the integument and fibrous sheath of the corpora
cavernosa, the glans and prepuce. The —
Helicine Arteries, — are vine-like branches, which project into the cavern-
ous spaces, and are most abundant in the back part of the corpora
cavernosa.
Veins, — empty into the dorsal vein of the penis and the prostatic venous
plexus. They form intricate and well-developed plexuses in the
erectile tissue.
Lymphatics, — the superficial terminate in the inguinal glands; the deep
join the deep lymphatics of the pelvis.
Nerves, — are derived from the internal pudic nerve, and the pelvic or
hypogastric plexus of the sympathetic.
THE TESTES
The Testes or Testicles are the glandular organs which secrete the
seminal fluid, — two oval bodies suspended obliquely in the scrotum by the
spermatic cords, each measuring about an inch in diameter, and weighing
THE TESTES
373
Their coverings, from without inward, are 6 in number,
Scrotum (see Fig. 131).
FIG. 130.
% oz. to an ounce,
as follows: —
Skin (4), — of the scrotum.
Dartos (5), — the vascular tunic.
Inter columnar Fascia, — the external spermatic fascia (6, Fig. 131).
Cremasteric Fascia (7, Fig. 131), — muscular fibres, the cremaster muscle,
derived from the lower border of the internal oblique muscle.
Infundibuliform Fascia (9, Fig. 131), — internal spermatic fascia, or fascia
propria; a continuation downward of the transversalis fascia.
Tunica Vaginalis, — the serous covering, originally a process of the perit-
oneum (see below).
The Scrotum is a cutaneous pouch, consisting of 2 layers — the in-
tegument and the Dartos; the latter being a contractile vascular tunic,
continuous with the superficial fascia of the
thighs and perinaeum, and forming a septum in
the scrotum between the two cavities for the
testes.
The Epididymis is an appendix to the testicle,
lying along its posterior border, and consists of a
single 'duct about 20 feet in length when unraveled,
but which is wound upon itself so as to occupy a
very small space. The —
Head or Globus Major (7), — is formed by the
coni vasculosi, or efferent ducts (6) of the
testis, which therein open into the single duct
which forms the epididymis.
Body (8), — is formed by the convolutions of the
tube, held together by fine connective tissue.
Tail or Globus Minor (9), — the lower expanded
portion, similarly formed, and connected to
the testis by cellular tissue.
Vas or Ductus Aberrans (n), — a narrow tube,
sometimes found opening into the canal of
the epididymis near its lower end, and ending in a blind extremity.
Hydatids of Morgagni (appendices testis), — small pedunculated bodies,
found attached to the epididymis or to the upper end of the testicle.
One of them is believed to be the remains of the duct of Muller.
Tunics of the Testis are 3 in number, — the tunica vaginalis, or serous
covering, externally; the tunica albuginea, or fibrous covering, in the
middle; and the tunica vasculosa, or pia mater testis, internally. The —
374
HUMAN ANATOMY
FIG. 131.
Tunica Vaginalis, the serous covering, — has a visceral layer (n) (tunica
vaginalis propria) and a parietal layer (8) (tunica vaginalis reflexa).
Originally a part of the peritoneum, its upper end becomes oblit-
erated, and the lower end remains as a closed sac, the space between
the layers being the cavity (10) of the tunica vaginalis. It forms a
pouch, the digital fossa (13), between the epididymis and the testicle.
Tunica Albuginea (12), the fibrous covering, — consists of white fibrous
tissue, and forms ari incomplete vertical septum within the gland, the
corpus Highmorianum or medi-
astinum testis (2), from which
fibrous bands (trabeculae) cross
the gland, dividing its interior
into spaces for the lobules of
the organ.
Tunica Vasculosa, the vascular
covering, — lies beneath the
preceding, and lines the septa
in the interior of the gland.
It consists of a plexus of
blood-vessels, held together by
a delicate areolar tissue.
Structure of the Testis. The
glandular structure consists of 250
to 400 olbules, which are each con-
tained in one of the spaces formed
by the trabeculae, and formed of i
to 3 or more minute, convoluted
tubes, the tubuli seminiferi. The latter consist of a basement mem-
brane, lined by several layers of cells, from which the spermatozoa are
developed. In the apices of the lobules the tubuli become straight, and
join to form 20 or 30 ducts, the —
Vasa Recta (4, Fig. 130), — are each about 3^o mcn in diameter; then
enter the mediastinum, passing upward and backward, and forming
the—
Rete Testis (5), — a network of anastomosing tubes or channels in the
fibrous stroma of the mediastinum; they end in the —
Vasa E/erentia (6), — 12 to 20 ducts, which perforate the tunica albu-
ginea of the testis, and form a number of conical masses, the coni
vasculosi which together constitute the globus major (7) of the
Epididymis (see Fig. 130).
APPENDAGES OF THE TESTES 375
Descent of the Testis. In early foetal life the testes are situated in
the abdominal cavity, just below the kidneys, and are connected to the
dartos of the scrotum and the tissues about the inguinal canal by a cord
named the gubtrnaculum testis, which prevents the testicle rising with the
growth of the foetus, and the testicle is drawn first into the inguinal canal
and eventually into the scrotum, the cord itself becoming shortened as
development proceeds. The descent begins about the commencement of
the 5th month; during the 7th month the testicle enters the inguinal
canal, and ordinarily arrives in the scrotum by the end of the 8th month.
A process of peritoneum is carried down in front of the testis; which
process, by obliteration of the canal, becomes a separate structure, the
tunica vaginalis. The structures of the inguinal canal are also brought
down with the testicle, and constitute some of its coverings.
Vessels and Nerves. The Arteries are the Spermatic, from the aorta
to the testicle itself; its coverings are supplied by the superficial and deep
External Pudic from the femoral, the superficial Perineal branch of the
Internal Pudic from the internal iliac, and the Cremasteric branch of the
epigastric from the external iliac.
Veins. — The spermatic veins emerge at the back of the testis, receive
branches from the epididymis, and unite into the convoluted pampini-
form plexus, which forms the chief mass of the spermatic cord. From
this plexus 3 or 4 veins arise, they unite into 2, and these join into
a single trunk, which on the right side empties into the inferior vena
cava, on the left side into the left renal vein.
Lymphatics, — of the testis terminate in the lumbar glands; those of its
coverings in the inguinal glands.
Nerves, — of the testes are derived from the spermatic plexus, joined by
filaments from the pelvic plexus; those of their coverings are the ilio-
inguinal branch of the lumbar plexus, the superficial perineal branches
of the internal pudic, the inferior pudendal branch of the small sciatic,
and the genital branch of the genito-crural.
APPENDAGES OF THE TESTES
The Vas Deferens (ductus deferens) is the continuation of the
epididymis, and the excretory duct of the testicle. Beginning at the
globus minor it ascends along the back of the spermatic cord to the in-
guinal canal, and enters the abdominal cavity through the internal ab-
dominal ring. It curves around the outer side of the epigastric artery,
crosses the external iliac vessels, and descends into the pelvis at the side
of the bladder, crossing to the inner side of the ureter and the inner
border of the vesicula seminalis. At the base of the prostate gland it
376 HUMAN ANATOMY
joins the duct of the seminal vesicle to form the ejaculatory duct. The
vas deferens is about 2 feet long, and has a canal of only half a line in
diameter. Its walls are very dense, making it feel like a piece of wire or
whip-cord when grasped between the fingers. In structure it consists of
three coats, the —
Areolar Coat, — externally, beneath which is the —
Muscular Coat, — in 2 layers of unstriped fibre, the outer longitudinal,
and the inner circular; but a third longitudinal layer is found at the
commencement of the vas, internal to the circular layer.
Mucous Coat, — internally, is pale and in longitudinal folds; its epi-
thelium is columnar.
Artery of the Vas or Ductus Deferens, — a branch of the superior vesical,
ramifies on its coats and anastomoses with the spermatic artery.
The Spermatic Cord (funiculus spermaticus) extends from the internal
abdominal ring to the globus minor of the epididymis, and is about 4
inches long. At the external abdominal ring it rests upon the inguinal
or Poupart's ligament, having the aponeurosis of the external oblique
muscle in front, and the conjoined tendon behind it. It is composed of
arteries, veins, lymphatics, nerves, and the vas deferens, bound together
by areolar tissue, and invested by the layers brought down by the descent
of the testicle. The structures, composing the spermatic cord, are 12 in
number, and are named as follows: the —
Vas or Ductus Deferens. Spermatic Plexus of Nerves.
Spermatic Artery. Branch of the Ileo-inguinal nerve.
Cremasteric Artery. Branch of the Genito-crural (genito-
Artery of the Vas Deferens. femoral) Nerve.
Deferential Veins. Obliterated Processus Vaginalis of the
Spermatic Veins. peritoneum (ligament of Cloquet).
Internal Cremaster Muscle. Lymphatics.
Coverings of the Cord, from within outward, are the —
Infundibuliform Fascia, from the transversalis fascia.
Cremasteric Fascia, from the internal oblique muscle.
Intercolumnar Fascia, the external spermatic fascia.
Superficial Fascia, and the Skin, of the scrotum.
The Vesiculae Seminales (d, Fig. 127) are two lobulated membranous
pouches, which serve as reservoirs for the semen, and secrete a fluid to
be added to the secretion of the testicles. They are about 2^2 inches long,
and are situated externally to the lower ends of the vasa or ductus defer-
entia, between the base of the bladder and the rectum. They are com-
posed of 3 coats, — an external areolar, a middle muscular, and an internal
THE VULVA 377
mucous coat, lined with columnar epithelium. Their anterior extremities
converge toward the base of the prostate gland, where a duct from each
joins with the corresponding vas or ductus deferens to form —
Ejaculatory Ducts (ductus ejaculatorii), — one on each side, are formed
by the junction of the vasa or ductus deferentia with the ducts
of the vesiculae seminales. They are about % inch in length, and
terminate in the prostatic portion of the urethra, by orifices on the
sides of the verumontanum (colliculus seminalis).
Arteries, — are derived from the middle and inferior vesical, and the
middle haemorrhoidal; they are accompanied by veins and lymphatics.
Nerves, — are branches from the pelvic or hypogastric plexus.
THE FEMALE ORGANS OF GENERATION
(Organa Genital ia Muliebria)
THE VULVA
The Vulva, or Pudendum Muliebre, are the external genital organs of the
female, viz., — the mons Veneris, the labia majora and minora, the clitoris,
and the orifice of the vagina. The —
Mons Veneris (commissura labiorum anterior), — is the rounded
eminence in front of the pubic symphysis, formed of fatty tissue
beneath the skin, and covered with hair after puberty.
The Labia Majora Pudendi (i) are two prominent longitudinal folds
extending from the mons Veneris to the perinaeum. They are formed
of hairy integument externally and modified skin internally, between
which are areolar and dartoid tissues, fat, vessels, nerves, and glands.
They meet in front, forming the anterior commissure (10), and nearly meet
behind in the posterior commissure at the anterior boundary of the peri-
naeum. They correspond to the scrotum of the male. The —
Fourchette (commissura labiorum posterior) (2), — is the curved anterior
edge of the perinaeum, and between it and the hymen (8) there is a
depression, the fossa navicularis.
Nerves, — the superficial perineal from the pudic, and the inferior
pudendal from the small sciatic.
The Labia Minora Pudendi (3), or Nymphce, are two small folds, situated
internally to the labia majora, and extending from the prepuce of the
clitoris (praeputium clitoridis) (4) obliquely backward for i% inches on
each side ot the vaginal orifice, where they are lost on the inner surface
of the labia majora. They are composed of modified skin, and have
378
HUMAN ANATOMY
FIG. 132.
sebaceous follicles (glandulaa vestibulares minores) on their internal
surface.
Clitoris, — is situated beneath the anterior commissure, its glans (4)
only appearing externally as a small rounded tubercle between the
anterior extremities of the labia
minora. It is a diminutive penis,
in all but the corpus spongiosum
and urethra; having two corpora
cavernosa, two crura, a glans,
prepuce, suspensory ligament and «-
muscles, the erectores clitoridis
(ischio-cavernosi) .
Vestibule (vestibulum vaginae) (6), —
is a triangular depression in front
of the vaginal orifice, bounded
laterally by the labia minora.
Meatus Urinarius (orificium urethras
externum) (5), — situated in the
vestibule, about an inch below the
clitoris, and close to the vaginal
orifice.
Bulbi Vestibuli, — are two oblong erec-
tile bodies, situated one on either
side of the vestibule, and consist- a.
ing of a venous plexus surrounded
by a fibrous membrane. They are
the analogues of the bulb of the
corpus spongiosum in the male.
Pars Intermedia, — is a small venous plexus situated between the glans
clitoridis and the bulbi vestibuli. It is the analogue of the corpus
spongiosum.
Orifice of the Vagina (7), — is surrounded by the sphincter vaginae
muscle, and in the virgin is sometimes partly closed by the hymen.
^H^men (8), — a fold of mucous membrane situated across the lower part
of the vaginal orifice, of various shapes, usually a ring, but often
semilunar, the concavity upward. It is frequently absent in virgins.
Its cicatrization after rupture gives rise to small eminences along
the margin of the vaginal orifice, named the caruncula myrtiformes
(carunculae hymenales).
Glands of Bartholin (glandulae vestibulares majores), — one on each side
of the vaginal orifice^ their ducts opening (9) near the inner sides of
THE VAGINA 379
the labia minora. They are the analogues of Cowper's glands
(glandulae bulbo-urethrales) in the male.
Nerves, — to the labia minora as to the labia majora; the bulbi vestibuli
and other erectile structures are supplied by filaments from the dorsal
nerve of the clitoris, superficial perineal, and hypogastric plexus.
THE VAGINA
The Vagina is a curved canal extending from the vulva to the ute ',
placed between the bladder in front and the rectum behind. Its len
is about 2^ inches along the anterior wall (paries anterior), 3^ inc*
along the posterior wall (paries posterior), and its walls are usually in co
tact with each other. It is very dilatable, especially near its upper em.
which surrounds the vaginal portion of the cervix uteri, its attachment
extending higher up on the posterior wall of the uterus than on the anterior
wall. Its relations are —
Anteriorly, — the urethra and the base of the bladder.
Posteriorly, — the anterior wall of the rectum, and the recto-vaginal fold
of peritoneum which forms Douglas' pouch (excavatio recto-uterina)
behind its upper fourth.
Laterally, — are attached the levatores ani muscles, and the recto-vesical
portion of the pelvic fascia.
Structure of the Vagina. The vaginal wall consists of a muscular coat
(tunica muscularis) externally, a layer of erectile tissue, and a mucous
lining (tunica mucosa) covered with squamous epithelium, and furnished
with mucous crypts and follicles, but has no glands. The vagina is par-
tially covered laterally by the recto-vesical portion of the pelvic fascia.
Columns of the Vagina (columnae rugarum anterior et posterior), —
are two longitudinal raphes situated along its inner surface, one
anteriorly, the other posteriorly, which are connected by numerous
transverse ridges or ruga vaginales.
Sphincter Vagina Muscle, — surrounds the lower end of the vagina; it is
described on page 99.
Vessels and Nerves. The Arteries of the vagina are the Vaginal
branches of the internal iliac, and branches of the uterine artery, which
form in front and behind a longitudinal vessel, the azygos arteries of the
vagina. The—
Veins, — are disposed similarly to the arteries, form a rich plexus in the
muscular and mucous coats, and terminate in the vaginal and uterine
trunks.
Lymphatics, — terminate in the pelvic and inguinal glands.
380 HUMAN ANATOMY
Nerves, — are derived from the hypogastric plexus, the fourth sacral
nerve, and the pudic nerve (n. pudendus), forming a vaginal plexus.
THE UTERUS
The Uterus is a hollow, pear-shaped, muscular organ, measuring about
3 inches long, 2 inches broad, and i inch thick, flattened from before back-
ward, placed base upward, forming ah angle with the vagina, which par-
tially receives its cervix, and situated in the pelvic cavity, between the
bladder in front and the rectum behind. Its —
Fundus uteri (A), — is broad, convex, having walls % inch thick, and is
covered by peritoneum.
Body (corpus uteri), — is about i% inches long, walls % inch thick, flat
anteriorly, convex posteriorly, concave laterally, and joined to the
bladder by its lower anterior fourth. It is invested by peritoneum
posteriorly, and in front for its upper three-fourths.
FIG. 133.
Cervix Uteri or Neck, — is the lower constricted portion, about i % inches
long, walls Y± inch in thickness, and is embraced for % to % inch
by the upper extremity of the vagina.
Cavity of the Body (cavum uteri) (B), — is small and triangular, flattened
from before backward, about i% inches in length, and has two lateral
cornua above, and a constricted orifice, the os internum (orificium in-
ternum uteri), at its lower angle, opening into the cavity of the
cervix.
Cavity of the Cervix (canalis cervicis uteri), — is spindle-shaped, about
i% inches long, and presents on its inner surf ace transverse folds of
mucous membrane proceeding from a longitudinal fold, giving an
appearance named the arbor vitce (plicae palmatae) (o).
Os Uteri (orificium externum uteri), — is a transverse orifice at the lower
THE UTERUS 381
end of the cervical cavity, opening into the vagina, and having an
anterior (labium anterius) and a posterior lip (labium posterius).
Ligaments of the Uterus are 8 in number, — i anterior, i posterior, 2
lateral or broad ligaments, 2 sacro-uterine, and 2 round ligaments, all
except the last-named being formed of peritoneum. The —
Anterior Ligament, utero-vesical, — is reflected from the front of the
uterus on to the bladder. It forms the floor of the utero-vesical pouch
(excavatio vesico-uterina).
Posterior Ligament, recto-vaginal, — passes from the posterior wall of the
uterus over the upper fourth of the vagina, and thence on to the
rectum and sacrum, forming Douglas' pouch (excavatio recto-uterina)
behind the upper portion of the vagina.
Lateral or Broad Ligaments (ligamenta lata uteri) 2, — pass from the
sides of the uterus to the lateral walls of the pelvis, and form a septum
across the pelvic cavity. They contain, between the two folds of
peritoneum of which they are composed, the Fallopian tubes (tubae
uterinas) the round ligaments, the ovaries, the parovaria or organs of
Rosenmiiller, connective tissue, unstriped muscular fibre, blood-
vessels, and nerves.
Sacro-uterine Ligaments (plicae recto-uterinae) 2, — pass from the sides
of the uterus to the sides of the rectum, and thence to the sacrum.
Round Ligaments (ligamenta teres uteri) 2 (G), — are two cords, about 4
or 5 inches long, composed of muscular tissue prolonged from the
uterus, also areolar and fibrous tissue, vessels and nerves, extending
one on each side, from the lateral aspects of the fundus uteri, through
the inguinal canals, to the labia majora, where they are lost. Each
ligament lies, for a part of its course, between the two layers of the
broad ligament, and is covered by a process of peritoneum. The —
Canal of Nuck, — is the extension of the above-mentioned process of
peritoneum into the inguinal canal. It exists in the foetus, but is
usually obliterated in the adult.
Structure of the Uterus. The wall of the uterus is composed of 3
coats, an External serous, a middle muscular, and an internal mucous coat.
The muscular coat (tunica muscularis) forms the chief bulk of the organ,
and consists of bundles of unstriped muscular fibres, disposed in 3 layers
interlaced together; circular fibres predominating in the cervix, longi-
tudinal fibres in the body of the uterus. The —
Peritoneal or Serous Coat (tunica serosa), — invests the body of the
organ, except its lower anterior fourth.
Mucous Coat (tunica mucosa), — is very thick, ^(2 to 3^ inch, and closely
382 HUMAN ANATOMY
adherent to the muscular tissue, having no basement layer of con-
nective tissue. It is covered with ciliated columnar epithelium, and
studded with mucous follicles and tubular glands (glandulse uterinae),
which are most numerous in the cervix.
Vessels and Nerves. The Arteries of the uterus are the Uterine from
the internal iliac, and the Ovarian from the aorta; the two meeting on the
side of the body and forming an anastomotic trunk, from which lateral
branches are given off to the uterus. They are remarkably tortuous and
anastomose freely. The —
Veins, — accompany the arteries, and in the impregnated state become
sinuses. They end in the uterine plexuses.
Lymphatics, — those of the cervix end in the pelvic glands, those of the
body in the lumbar glands.
Nerves, — are derived from the inferior hypogastric and ovarian plexuses,
and from the 3d and 4th sacral nerves.
APPENDAGES OF THE UTERUS
The Fallopian Tubes, or Oviducts (tubas uterinae) (D), are two tubes,
each about 4 inches in length, and i H 6 inch in calibre, situated in the free
margin of the broad ligament, and extending from the superior angles of
the uterus (&) outward, to terminate in free, trumpet-shaped ends. They
open by one end into the uterus at its cornua, by the other end into the
peritoneal cavity. Their structure is similar to that of the uterus, the
mucous lining being continuous with the uterine mucous membrane and
with the peritoneum, and lined with ciliated columnar epithelium. Their —
Isthmus Tubes Uterines, — is the inner constricted third of the tube.
Ampulla Tubes Uterines, — is the outer dilated portion, curving over the
ovary.
Infundibulum Tubes Uterince, — the trumpet-shaped outer end, with its
open mouth, the ostium abdominale tubce uterince, surrounded by —
Fimbrice Tubes Uterines (E), — fringe-like processes, one of which, the
fimbria ovarica, is attached to the ovary.
Hydatids of Morgagni (appendices vesiculosi) (see page 372), — one or
more small vesicles floating on a long stalk of peritoneum, are fre-
quently found in connection with or near the fimbriae.
Vessels and Nerves, — The vessels are those of the ovaries; the nerves are
branches from one of the uterine nerves.
The Ovaries (ovaria) (F) are two oval bodies, of grayish-pink color,
situated in the broad ligament, behind and below the Fallopian tubes,
( tubae uterinae,) one on each side of the uterus, to which they are attached
THE MAMMAE 383
by the ligament of the ovary. They each measure about i % inches by %
by H, and are invested by peritoneum, except posteriorly. They are
composed of a vascular stroma containing the Graafian vesicles (folliculi
oophori vesiculosi) in various stages of development, and are surrounded
by the tunica albuginea, a condensed layer of the stroma.
The Graafian Vesicles (folliculi oophori vesiculosi) are the ovisacs
containing the ova, are very numerous (about 70,000 in each
ovary), vary in diameter from Hoo to %o inch, but after puberty a few
are found of from Ho to ^ inch or more. Each vesicle has an external
fibro-vascular coat, and an internal coat (tunica externa) or ovicapsule,
(theca folliculi) which is lined by the membrana granulosa (stratum
granulosum) and contains a transparent fluid of albuminous character,
containing the immature ovum. The —
Membrana Granulosa (stratum granulosum), — is a layer of nucleated
cells, lining the ovicapsule; at one point the cells are heaped up in a
mass, the discus proligerus (cumulus oophorus), in which the ovum
is embedded.
Corpus Luteum, — is a puckered yellow spot in the substance of the
ovary, produced as a result of the rupture of a Graafian vesicle and the
discharge of an ovum, probably by the organization of the extrava-
sated blood, forming lutein cells. In old age the corpus luteum
undergoes involution, loses its yellow color, and is then called the
corpus albicans.
Vessels and Nerves. The Arteries are the Ovarian, from the aorta,
which also supply the Fallopian tubes, and anastomose with the uterine
arteries. The —
Veins, — accompany the arteries, and form a plexus, the pampiniform
plexus, near the ovary.
Nerves, — are derived from the inferior hypogastric or pelvic plexus, and
from the ovarian plexus.
The Parovarium, or Organ of Rosenmuller, is a group of tubules, situated
in the broad ligament, between the ovary arid the Fallopian tube, and con-
verging to a large duct, the duct of Gartner, which ramifies in the broad
ligament, descends along the side of the uterus, and terminates in a bulb-
ous enlargement. It is the atrophied remains of the Wolffian Body of
fcetal life.
THE MAMMAE
The Mammae, or Breasts, are two hemispherical eminences, situated one
on each antero-lateral aspect of the chest, extending from the sternum
to the axilla, and from the 3d rib to the 7th. Each breast contains the
384
HUMAN ANATOMY
Mammary Gland (corpus mammae) and is surmounted by the nipple
(papilla mammae), around the base of which is a zone of colored cutaneous
tissue, the areola mamma, pink in virgins, darker in women who have
borne children. In the male the mammae
.r IG« 134"
are rudimentary organs, but capable of
development under special circumstances.
Structure of the Mammary Gland. Is
composed of 15 or 20 lobes (lobi mammae)
and their ducts (i), with a packing of
areolar and adipose tissue (subcutaneous
tela), enveloped by a thin fibrous capsule
or stroma which forms septa between the
lobes. Each lobe is made up of lobules
(2), and these again are formed by the
aggregation of alveoli, terminal vesicles
by which the milk is secreted. The —
Tubuli Lactiferi (ductus lactiferi) (i),
— are the excretory ducts of the
lobes, one for each. They are formed
by the junction of the ducts from
each lobule, and converge towards
the areola, beneath which they form
ampulla or dilatations, and thence,
piercing the nipple, open on its summit by separate orifices.
Vessels and Nerves. The Arteries are derived from the thoracic
branches of the axillary, the intercostals, and the internal mammary
arteries.
Veins, — form the circulus venosus, an anastomotic venous circle around
the base of the nipple, from which larger veins run outward, and ter-
minate in the axillary and internal mammary veins.
Lymphatics, — terminate in the axillary glands; a few going to the
anterior mediastinal glands.
Nerves, — are derived from the lateral cutaneous branches of the 4th,
5th, and 6th intercostal nerves and from the thoracic portion of the
sympathetic cord.
HERNIA
A Hernia is a protrusion of any viscus from its natural cavity. The
term, when unqualified as to the viscus, is understood to mean a protrusion
of the intestines or mesentery, or both, from the abdominal cavity. Ana-
tomically the most important hernias are —
INGUINAL HERNIA 385
Oblique Inguinal Hernia, — in which the protrusion follows the spermatic
cord through the inguinal canal; passing to the outer side of the epi-
gastric artery, and through both the internal and external abdominal
rings.
Direct Inguinal Hernia, — occurs at Hesselbach's triangle, escaping to
the inner side of the epigastric artery, and through the subcutaneous
inguinal or external abdominal ring only.
Femoral Hernia, — in which the protrusion descends through the femoral
or crural canal.
H INGUINAL HERNIA
The Inguinal Canal is a passage in the abdominal wall, parallel to the
inguinal or Poupart's ligament, and just above it. It commences at the
abdominal inguinal or internal abdominal ring and ends at the subcu-
taneous inguinal or external abdominal ring (i), being about i^ inches in
length. It serves for the passage of the spermatic cord in the male, and
the round ligament of the uterus in the female; is directed downward and
inward, and is bounded as follows: —
Anteriorly, — the skin, superficial fascia, (camper's) external oblique
muscle for its entire length, and the internal oblique (the part
attached to the inguinal ligament) for the outer third of the canal.
Posteriorly, — the conjoined tendon of the internal oblique and trans-
versalis, transversalis fascia, triangular fascia (5) for the medial
two-thirds, sub-peritoneal tissue, transversalis fascia, and peritoneum
for its entire length.
Above, — the arched fibres of the internal oblique and transversalis
muscles.
Below, — the union of the transversalis fascia (5) with Poupart's (in-
guinal) ligament (10).
The Internal or Deep Abdominal Ring (annulus inguinalis abdo minis), —
is an oval opening in the transversalis fascia, formed by the prolongation
of this fascia around the cord, as the infundibuliform fascia. It lies Y2
inch above Poupart's (inguinal) ligament (10) and midway between the
anterior superior spine of the ilium and the spine of the pubes (8). It is
bounded above and externally by the arched fibres of the transversalis
muscle; below and internally by the epigastric vessels. The —
Deep Epigastric Artery, — lies between the transversalis fascia and the
peritoneum, passing obliquely upward and inward along the lower and
inner margins of the internal ring.
Infundibuliform Fascia, — or infundibuliform process of the transversalis
fascia, is a thin, funnel-shaped membrane, arises from the circum-
25
386
HUMAN ANATOMY
ference of the internal ring, and is continued (internal spermatic
fascia) around the cord and testis, enclosing them in a distinct
pouch.
The External or Superficial Abdominal Ring (annulus inguinalis sub-
cutaneous) (i), — is a somewhat triangular opening in the aponeurosis of
the external oblique muscle, situated just above and external to the crest
of the pubes. It is about i inch long, and ^ inch wide, and is bounded
laterally by its own margins, called the external (crus inferius) (2) and
internal (crus superius) (3) pillars of the ring. It may be easily felt in
10
the living male, by invaginating the skin of the scrotum with the finger,
and feeling up along the spermatic cord (9). It is much larger in men
than in women. The —
Inter columnar or External Spermatic Fascia (fibrae intercrurales) (6), —
is formed by tendinous fibres which arch across the lower part of the
aponeurosis of the external oblique, between the pillars of the ex-
ternal ring, and are connected together by delicate fibrous tissue.
It is continued downward as a tubular prolongation around the cord
and testis, enclosing them in a distinct sheath.
Cremasteric Fascia (fascia cremasterica), — passes through the external
ring, and consists of a series of muscular loops, united by areolar
tissue, forming a thin covering over the spermatic cord and testis.
INGUINAL HERNIA
38?
The muscular fibres (Cremaster muscle) are supposed to have been
originally part of the internal oblique muscle, carried down by the
testicle in its descent to the scrotum. It does not exist in the
female.
FIG. 136.
Poupart's Ligament (ligamentum inguinale), or the Crural Arch, is
that portion of the aponeurosis of the external oblique muscle which
extends from the anterior supe-
rior spine of the ilium to the
spine of the pubes. Its lower
portion (3) forms the external
pillar of the external abdominal
ring, and its reflection along the
pectineal line is called Gimbernafs
ligament (ligamentum lacunare)
(2). Other fibres, reflected be-
hind the internal pillar of the
ring (4), upward to the linea
alba, are termed the triangular
fascia (ligamentum inguinale re-
flexum) (i).
Gimbernat's Ligament (liga-
mentum lacunare) (2), — is
that portion of the aponeu-
rosis of the external oblique
which is reflected upward
and outward from the spine
of the os pubis to be inserted
into the pectineal line. Its>
anterior margin is continuous with Poupart's (inguinal) ligament.
Triangular Fascia (ligamentum inguinale reflexum) (i),— is a tri-
angular band, attached by its apex to the pectineal line, where it ia
continuous with Gimbernat's (lacunar) ligament; passes inward
beneath the spermatic cord, behind the internal pillar (crus superius)
of the external or subcutaneous inguinal ring, and in front of the
conjoined tendon, to interlace with its fellow of the opposite side at
the linea alba (see 5, Fig. 134). It is often undeveloped or wanting.
Hesselbach's Triangle is a small triangular space on the lower ab-
dominal wall, bounded externally by the deep epigastric artery, internally
by the margin of the rectus muscle, below by Poupart's (inguinal) liga-
388 HUMAN ANATOMY
ment. Its inner ^ is crossed by the conjoined tendon. Through this
space a direct inguinal hernia forces its way. The —
Inguinal Peritoneal Fossce, — are 3 depressions of peritoneum in the in-
guinal region above Poupart's (inguinal) ligament. The internal
(fovea supravesicalis) and middle (fovea inguinalis medialis) ones lie
in Hesselbach's triangle, the external fossa (fovea inguinalis lateralis)
usually corresponds to the internal abdominal or abdominal inguinal
ring.
Coverings of Inguinal Hernia depend, in the oblique form, upon the
extent to which the hernia descends in or through the inguinal canal.
When it has escaped from the external abdominal or subcutaneous in-
guinal ring, and is therefore complete, its coverings, from without inward,
are 7 in number, as follows: —
1. Skin.
2. Superficial Fascia, — 2 layers.
3. Inter columnar Fascia, — from the external abdominal ring.
4. Cremasteric Fascia, — from the inguinal canal.
5. Infundibuliform Fascia, — from the internal abdominal ring.
6. Subserous Areolar Tissue, — almost inappreciable.
7. Peritoneum, — the hernial sac proper.
Direct Inguinal Hernia has the same coverings, except that the Conjoined
Tendon is substituted for the cremasteric fascia, and the Transversalis
Fascia for the infundibuliform.
FEMORAL HERNIA
The Femoral or Crural Canal is a narrow interval, % to % inch long,
between the femoral vein (4) and the inner wall of the femoral sheath
(fascia cruris), extending from Gimbernat's (lacunar) ligament to the
saphenous opening (fossa ovalis). It exists as a distinct canal only when
the sheath has been separated from the vein by the pressure of a hernia
or tumor, or by dissection. It lies beneath Poupart's (inguinal) ligament
(i), is closed above by the septum crurale of Cloquet (septum femorale),
below by the cribriform fascia (fascia cribrosa), and is bounded as follows: —
Anteriorly, — by a continuation downward, under Poupart's (inguinal)
ligament, of the transversalis fascia, covered by the falciform process
(margo falciformis) of the fascia lata.
Posteriorly, — by a downward continuation of the iliac fascia, covering
the pubic portion of the fascia lata.
Externally, — by the fibrous septum separating it from the inner side of
the femoral vein.
FEMORAL HERNIA
389
FIG. 137.
Internally, — by the outer edge of Gimbernat's (lacunar) ligament, and
the junction of the processes of the transversalis fascia and the iliac
fascia, which form the inner side of the femoral sheath.
The Femoral or Crural Ring (annul us femoralis), the upper opening of
the femoral canal, is an oval-shaped opening, about ^ inch in diameter
(larger in the female), situated
below the internal abdominal or
subcutaneous inguinal ring (7) and
Poupart's (inguinal) ligament (i),
and between the inner side of the
femoral vein and the margin of
Gimbernat's (lacunar) ligament
(5). It is closed by the septum
crurale (septum femorale) and a
small lymphatic gland. The arrow
in the figure points into the fem-
oral ring. The —
Femoral Vein (4), — lies next on
its outer side.
Deep Epigastric Artery (a. epi-
gastrica inferior), — crosses its
upper and outer angle.
Obturator Artery, — when arising from a common trunk with the epi-
gastric, as it does once in 3^ subjects, may lie close along its internal
and superior margins.
Communicating Branch, — between the deep epigastric and obturator
arteries, lies in front of the ring.
Spermatic Cord (funiculus spermaticus), — in the male, lies directly above
its anterior margin, replaced by the round ligament in the female.
Septum Crurale, or Fascia of Cloquet (septum femorale), — is a layer of
condensed areolar tissue, supporting a lymphatic gland, and per-
forated for the passage of lymphatic vessels. It lies across the femoral
ring, and forms one of the coverings to any hernia escaping thereby.
The Saphenous Opening (fossa ovalis), the lower orifice of the femoral
canal, is an oval-shaped aperture, i^ by ^ inch in diameter, formed by a
reflection of the fascia lata inward, around and under the end of the in-
ternal saphenous vein (3). It is situated below the inner third of Pou-
part's (inguinal) ligament, and is covered by the cribriform fascia (fascia
cribrosa). Its inner margin curves upward behind the saphenous vein
and under the outer margin, and is blended with the pubic portion of the
HUMAN ANATOMY
fascia lata over the pectineus muscle. Its outer margin curves over the
inner to the spine of the pubes, as a —
Falciform Process, or Superior Cornu (margo falciformis), — is thin but
strong, sharply defined, and lies on a plane anterior to the inner
margin. It ascends in front of the femoral vessels, and curving
inward is attached toPoupart's (inguinal) ligament, the spine of theos
pubis, and the pectineal line, where it is continuous with the pubic
portion. It is sometimes named the ligament of Burns, its pubic end
is called the ligament of Hey.
Cribriform Fascia (fascia cribrosa) (n, Fig. 134), — is the portion of the
deep layer (Scarpa's) of the superficial fascia which covers the
saphenous opening (fossa ovalis). It is perforated by the internal
saphenous vein and by numerous blood-vessels and lymphatics.
The Femoral or Crural Sheath, the investing sheath of the femoral ves-
sels, is a funnel-shaped prolongation of the lining fasciae of the abdomen,
the transversalis fascia in front, and the iliac fascia behind. The sheath
is divided by two septa into 3 compartments, the external of which
contains the femoral artery, the middle one the femoral vein, the internal
one being the femoral canal. The sheath is perforated anteriorly by the
genito-crural nerve, internally by the internal saphenous vein, and forms
one of the coverings of a femoral hernia. The —
Deep Crural Arch, — is the thickened border of the transversalis fascia,
which arches across the front of the crural sheath, and is intimately
connected to it. Externally it is attached to the centre of Poupart's
(inguinal) ligament, internally it is inserted into the pectineal line
/behind the conjoined tendon.
Coverings of Femoral Hernia depend upon whether the hernia has or
has not escaped from the saphenous opening (fossa ovalis) , and is therefore
complete or incomplete. In the latter case, the covering, from without
inward would be — skin, superficial fascia, cribriform fascia, femoral
sheath, septum crurale, subserous areolar tissue (fascia propria of Sir
Astley Cooper), and peritoneum. The coverings of a complete femoral
. Jifitnia. axe. as follows: —
i. Skin.
I 2. Superficial Fascia, — its superficial layer (subcutaneous tela).
3. Cribriform Fascia, — from the saphenous opening.
4. Femoral Sheath, — from the transversalis fascia.
5. Septum Crurale, — from the femoral ring.
6. Subserous Areolar Tissue, — the fascia propria of Cooper.
7. Peritoneum, — the proper hernial sac.
THE PELVIC CAVITY 39 1
THE PERINEUM, PROPER
The Perinaeum is a triangular space containing the structures which
close the inferior outlet of the pelvic cavity anterior to a line drawn be-
tween the tuberosities of the ischia. Posteriorly to thisline the correspond-
ing space is named the I schio-rectal Region. The Perinaeum is bounded
laterally by the rami of the pubes and ischia, anteriorly by the symphysis
pubis, and posteriorly by the line above mentioned, which averages about
2% inches in length.
For the Muscles of the Perinaeum, see page 98.
THE PELVIC CAVITY
The Pelvic Cavity is that portion of the abdominal cavity which lies
below the level of the ilio-pectineal line and the promontory of the sacrum.
The osseous pelvis is described on page 9. The boundaries of the pelvic
cavity are as follows: — •
Anteriorly and Laterally, — the pubes and ischia, covered by the obturator
muscles.
Posteriorly, — the sacrum and coccyx, the pyriformis muscles, and the
great sacro-sciatic ligaments (lig. sacro-tuberosa).
Floor, — is formed by the recto-vesical fascia, covering the levator ani
and coccygeus muscles of each side, and the triangular ligament
(diaphragma-urogenitale) of the urethra.
Contents of the Pelvic Cavity are the bladder, rectum, some convolu-
tions of the small intestine, and some of the organs of generation. They
are partially covered by peritoneum, and supplied with vessels and nerves.
THE PELVIC FASCIA
The Pelvic Fascia lines the pelvic cavity and is continuous with the
iliac and transversalis fascia above. At the level of a line drawn from the
back of the symphysis pubis to the spine of the ischium, it is thickened into
a white line or band (arcus tendineus), where it gives origin to the levator
ani muscle, and divides into 2 layers, the recto-vesical fascia or visceral
layer, and the obturator fascia or parietal layer. The —
Recto-vesical Fascia, visceral layer of the pelvic fascia, — descends from
the white line (arcus tendineus) over the upper or pelvic surface of
the levator ani muscle, and is prolonged over the prostate gland,
rectum, vesiculae seminales, and the bladder, forming the lateral true
ligaments of the latter organ.
Obturator Fascia, the parietal layer of the pelvic fascia, — descends from
the white line along the wall of the pelvis, and covers the obturator
392
HUMAN ANATOMY
interims muscle, near the lower border of which it forms a canal be-
tween its layers, Alcock's canal) for the pudic vessels and nerve.
Above this canal it gives off a thin membrane, the ischio-rectal or anal
fascia over the lower or perineal surface of the levator ani muscle; also
a process, which with its fellow of the opposite side forms the deep
(superior) layer of the triangular ligament (diaphragma urogenitale).
Illustration of the Pelvic Fascia. The capital letter K, having a hori-
zontal arm added to it, thus K™, will illustrate the pelvic fascia of the right
side, seen from the front in vertical section. The vertical line of the K
represents the pelvic fascia above, the obturator fascia below. The upper
arm represents the lateral ligament of the bladder, the horizontal arm the
recto-vesical fascia, and the lower arm the ischio-rectal fascia. The space
between the lower arm and the vertical line represents the ischio-rectal
fossa.
THE MALE PERINEUM
The Male Perinaeum, in the adult, varies in breadth on the base line,
from 2 to 3^ inches, the average FIG. 138.
being 2% inches. Its middle line
is convex, corresponds to the bulb
of the urethra, and presents a
prominent raphe, which is con-
tinuous in front with the raphe
of the scrotum. Its muscles are
described on page 98.
Fasciae of the Perinaeum are
superficial and deep, each con-
sisting of two layers; the deep
fascia being usually called the
triangular ligament of the urethra.
The—
Superficial Layer of the Super-
ficial Fascia (subcutaneous
tela), — is thick, loaded with
fat, and continuous with the
subcutaneous fascia of the
thighs.
Deep Layer of the Superficial Fascia, Colics' Fascia, — is thin but strong,
continuous in front with the dartos of the scrotum, and attached on
each side to the rami of the pubes and ischium; posteriorly it joins the
deep perimeal fascia under the superficial transversus perinaei muscle.
THE MALE PERINEUM 393
Superficial Layer of the Deep Perinaal Fascia (fascia diaphragmatis
urogenitalis inferior), — is triangular in shape, and extends from the
sides of the pubic arch and the sub-pubic ligament, laterally to the
rami of the pubes and ischia, and posteriorly to the central tend-
inous portion of the perinaeum, where it becomes blended with
Colic's fascia and the deep layer of the deep fascia. It embraces
the anterior part of the membranous portion of the urethra.
Deep Layer of the Deep Perinceal Fascia (fascia diaphragmatis urogenitalis
superior), — has the same attachments as the superficial layer above
described, in its course it embraces the posterior part of the mem-
branous portion of the urethra, and is in connection with the apex
of the prostate gland.
Buck's Fascia is a continuation of the deep layer of the superficial fascia
of the perinaeum, extending forward upon the penis, which itinvests com-
pletely as far as the glans. It is continuous above with the suspensory
ligament of the penis, and is held by some anatomists to prove that the
deep layer aforesaid is not continuous in front with the dartos of the
scrotum. This fascia was named from Dr. Buck, an American surgeon,
who, in 1846, first insisted on the importance of this structure. It modifies
the direction of urinary infiltration of the perinaeum, until perforated.
The Superficial Perin&al Interspace or Fossa is the interval between the
deep layer of the superficial fascia (Colles' fascia) and the triangular
ligament or urogenital diaphragm. It contains the following
structures: —
Crura of the Penis (4). 1 ' schio-cavernosus or Erector Penis
Corpus Spongiosum (corpus Muscle (10).
cavernosum urethrae). Superficial Transversus Pcrincei
Bulb of the Urethra. Muscle (14).
Bulbo-cavernosus or Accelerator Superficial Transversus Perinai
Urines Muscle (8). Artery.
Superficial Perinaal Vessels and
Nerves (5).
The Deep Perinceal Interspace or Fossa is the interval between the two
layers of the triangular ligament or urogenital diaphragm. It
contains the following structures: —
Membranous Urethra. Dorsal Vein of the Penis.
Deep Transversus Perinai or Com- Artery of the Bulb,
pressor Urethrce Muscle. Nerve of the Bulb.
Pudic Vessels and Nerve (n). Plexus of Veins.
Cowper's Glands (glandula bulbo-
yrethrales) and Ducts.
394
HUMAN ANATOMY
Central Tendinous Point is a fibrous point in the middle line of the
perinaeum, internal to the deep layer of the superficial fascia and about %
inch in front of the anus. It corresponds to the centre of the posterior
margin or base of the triangular ligament or urogenital diaphragm (12),
and is the point of attachment for 4 converging muscles, the — external
sphincter (16), bulbo-cavernosus or accelerator urinae (8), and two super-
ficial transverse perinaeal (14).
ISCHIO-RECTAL REGION
The Ischio-rectal Space is the horse-shoe-shaped space behind and above
the perinaeum. It is somewhat triangular in cross-section. It extends
posteriorly to the tip of the coccyx, laterally to the tuberosities and rami
of the ischia and anteriorly, on each side, it presents an Anterior Exten-
sion which extends forwards as far as the body of the pubis. In fat sub-
jects this extension is distended with fat, in which case it is triangular
FIG. 139.
in cross -section, the floor being formed by the deep layer of the trian-
gular ligament (uro-genital diaphragm), outer wall by obturator fascia
and muscle, and the inner wall by the leva tor an i muscle and its fascia.
In the middle line it presents the anal orifice, and deeply on each side,
the Ischio-rectal Fossa, which contains the lower part of the rectum, areolar
tissue and fat. The fossa is about i inch broad at its base and about 2
THE FEMALE PERINEUM 395
inches deep; its apex, directed upward, corresponds to the junction of the
obturator fascia and the ischio-rectal fascia. It contains the — •
Superficial Fascia (subcutaneous tela), — is thick, areolar in texture,
with much fat in its meshes, also branches of the perforating cu-
taneous nerve. It is a single layer.
Muscles, — the corrugator cutis ani, external and internal sphincters (16),
and the levator ani (18).
Rectum, — surrounded by areolar tissue and fat.
Internal Pudic (pudenda!) Artery (n), — with its veins and the two
divisions of the nerve, about ^ inch above the margin of the tuber-
osity of the ischium.
Inferior Hemorrhoidal Vessels and Nerves (13), — cross the space trans-
versely.
Superficial Perinceal Vessels (5) and Nerves (3), — in the front part of the
space for a short distance.
Branch of the ^th Sacral Nerve, — at the back of the space, near the coccyx.
Ischio-rectal or Anal Fascia, — a thin membrane given off from the obtu-
rator fascia over the levator ani muscle, at the apex of the fossa (see
pages 390-391).
Obturator Fascia, — covering the obturator internus muscle, at the outer
side of the fossa (see page 390).
Recto-vesical Fascia, — invests the internal surface of the levator ani
muscle, near the base of the fossa; also the rectum at the inner side
of the fossa (see page 390).
THE FEMALE PERINEUM
The Female Perinaeum performs the special function of supporting the
posterior wall of the vagina, and thereby aiding materially in the support
of the whole vagina, the uterus and the bladder. The —
PerincBal Body, — is the pyramidal-shaped prolongation of the female
perinaeum upward between the vagina and the rectum. It measures
about \Y± inches antero-posteriorly, and extends laterally from one
ischial tuberosity to the other. In it are situated the muscles of the
external organs of generation.
Differences between the Female and Male Perinsea are chiefly due
to the perforation of the structures in the median line of the female
perinaeum by the vulvo-vaginal passage. The —
Superficial Fascia, — is incomplete, by reason of its perforation by the
orifice of the vulva, but consists of two layers, subcutaneous tela and
Colics' fascia, as in the male.
396 HUMAN ANATOMY
Deep Perinaal Fascia (urogenital diaphragm), — being also perforated
by the vagina is less apparent than in the male, though presenting
two layers, with the urethra perforating them, as in the other sex.
Bulbi Vestibuli and Paries Intermediates, — represent the corpus spongio-
sum of the male, divided into two lateral segments.
Prostate Gland, — is absent in the female, but its place is occupied by a
number of minute glands disposed around the neck of the bladder.
Muscles, — The Sphincter Vaginae in the female, takes the place of the
bulbo-cavernosus or accelerator urinse in the male; the Superficial
Transversus Perinaei is similar in both sexes; the Erector Clitoridis
is smaller than the erector penis, but differs in no other respect;
both are called ischio-cavernosus; the Deep Transversi Perinaei
or Compressores Urethras are separate and attenuated in the
female, their anterior fibres passing in front of the urethra, the
middle fibres to the sides of the vagina, the posterior fibres to
the central tendinous point of the perinaeum.
Structures Divided in Lithotomy. In the Lateral Operation the
knife is inserted deeply i^ inches in front of the anus, a little to the left
of the median line, and the incision is carried obliquely backward and
outward, becoming more superficial as it is extended, to a point midway
between the anus and the tuberosity of the left ischium, dividing the —
Skin and Superficial Fascia (first layer of the latter).
Inferior Hemorrhoidal Vessels and Nerves (13).
Deep Layer of the Superficial Fascia (6).
Superficial Perinaal Vessels (5) and Nerves (3).
Bulbo-cavernosus (Accelerator Urinae) Muscle (8) (posterior fibres).
Superficial Transversus Ferincei Muscle (14) and Artery.
Inferior Layer of the Triangular Ligament (12).
Deep Transversus Perin&al (Compressor Urelhrce) Muscle (a few fibres).
Levator Ani Muscle (18) (anterior fibres).
Membranous and Prostatic Portions of the Urethra (2).
Superior Layer of the Triangular Ligament (Urogenital diaphragm) (12).
Prostate Gland (part of the left lobe).
Neck of the Bladder (in part).
In Median Lithotomy, the incision, i}-^ inches long, is made transversely
through the central tendinous point and raphe, dividing the —
Skin and Superficial Fascia.
Sphincter Ani Muscle (16) (some of its anterior fibres).
Branches of the Transverse Perinceal Vessels and Nerves.
Base of the Triangular Ligament (Urogenital diaphragm) (12).
LITHOTOMY 3Q7
Membranous Portion of the Urethra (2).
Bulbo-Cavernosus (Compressor Urethra) Muscle.
Structures to be Avoided in Lithotomy. In the Lateral Operation
the structures to be remembered and avoided in making the incision are
the—
Bulb, its Artery, and the Rectum, — inwardly and in front; avoided by
not making the primary incision too near the middle line nor too far
forward.
Pudlc Artery di), — externally; avoided by not carrying the incision too
far outwardly.
Prostrate Gland and Veins, — behind; avoided by not carrying the deep
incision too far backward, so as to cut through the entire lobe of the
prostate gland, permitting the urine to infiltrate into the loose areolar
tissue around the rectum, instead of escaping externally.
INDEX
ABDOMEN, 323
Regions of, 323
Abdominal Brain, 240
Cavity, 323
Openings of, 324
Rings, 385, 386
Acervulus Cerebri, 194
Acetabulum, 12
Achillis, Tendo, 113
Adenology, i
Ala Cinerea, 212
Ala Lobuli Centralis, 207
Alcock's Canal, 392
Alveoli, 3, 29, 33
of Lungs, 359
of Mammary Gland, 384
Amphiarthrosis, 59
Ampulla of Fallopian Tube, 382
of Milk Ducts, 384
of Semicircular Canals, 306
of Tubae Uterinae, 382
Amygdala, 207, 3M
Anastomosis, 145
Circumpatellar, 146
Crucial, 146
Elbow, 145
Hip, 145
Knee, 146
Shoulder, 145
Stirrup, 145
Tonsillar, 314
of Willis, 128, 151
Anatomy, i
Angiology, i
Angle, Filtration, 287
of Iris, 287
of Jaw, 35
Ankle-joint, 71
Annulus, Ciliaris, 146
Femoralis, 389
Fibrosus Sinister, 121
Inguinalis Abdominalis, 385
Subcutaneous, 386
Ovalis, 119
Anterior Extension (ischio-rectal fossa),
393
Anti-helix, 297
Anti-tragus, 297
Antrum of Highmore, 27
Mastoideum, 301
Tympanicum, 301
Anus, 335
Aorta. 123
Abdominal, 137. 156
Arch of, 123, 449
Thoracic, 136, 154
Aortic Bodies, 345
Apertura Pyraformis, 44
Apertures in Abdominal Wall, 324
Apex Capituli, 55
Appendices Epiploicae, 328, 335
Testis. 373
Appendix Auriculae, 119
Ensiform, 8
Ventriculae, 354
Vermiform, 334
Xiphoid, 8
Aponeuroses, 74
Aponeurosis, Pharyngeal, 322
Vertebral, 90
Apophysis, 3
Aquaeduct of Sylvius, 202
Aquaeductus Cerebri, 202
Cochleae, 21, 43, 306
Fallopii, 220, 225
Vestibuli, 21, 42, 305
Arachnoid of Brain, 181
of Cord, 213
Granulations, 181, 182
Arbor Vitae, 208, 380
Arch, Carpal, 135
Crural, 387, 39O
Glosso-palatine, 314
Lumbo-costal, 107
Palmar, 135
Pharyngo-palatine, 314
Plantar, 145
Superciliary, 14
Volar, 135
Arcuate Fibres, Cerebellar, 208
Medullary, 210
Area Cribrosa, 311
n. Facialis, 311
Vestibularis, 311
Areola Mammae, 384
Arm, 47
Arnold's Ganglion, 224
Nerve, 221, 250
Arterias Cavernosae, 127
Propriae Renales, 362
Receptaculi, 127
Arterial Anastomoses, 145
System Tabulated, 147
Arteriolae Rectae, 362
Artery or Arteries, 122, 147
Acromio-trmracic, 132, 153
Alar-thoracic, 132, 153
Alveolar, Inferior, 126, 150
Superior, 126, 150
Anastomoses of, 145
Anastomotica Magna (arm) , 133. 1 53
(thigh), 142, 1 60
399
400
INDEX
Artery, Angular, 125, 148
of Ankle-joint, 71
Anonyma, 124, 148
Antero-lateral Ganglionic, 127, 151
Antero-medial Ganglionic, 127, 151
Aorta, 123
Abdominal, 137, 156
Arch of, 123, 148
Thoracic, 136, 154
Arch, Palmar (volar), Deep, 136,
153
Superficial, 135, 154
Plantar, 145, 162
Arcuata, 144, 162
Ascending Pharyngeal, 125, 150
of Auditory Canal, 298
Auditory, Internal, 312
of Auricle, 298
Auricular, 125, 148
Anterior, 126, 150
Deep, 126, 150
Posterior, 125, 150
Axillary, 132, 153
Axis, Coeliac, 137, 156
Thyroid, 131, 152
Azygos of Knee, 143, 162
of Vagina, 139, 379
Basal, 127
Basilar, 131, 151, 152
of Bladder, 368
Brachial, 133, 136, 153
of Brain, Cortical, 128
of Bones, 4
Bronchial, 136, 154, 356
Buccal, 126, 150
Bulbar, 131, 152
Bulbi Urethras, 140, 158
Calcanean, 144, 162
Canalis Pterygoidea, 126, 150
Carotid, Common, 124, 148, 150
External, 125, 148, 150
Internal, 126, 151
Carotico-tympanic, 127, 151
Carpal, Arch, Anterior, 135
Posterior, 135
Radial, Anterior, 133, 153
Posterior, 134, 153
Ulnar, Anterior, 135, 154
Posterior, 135, 154
Cavernosae, 127, 151
Centralis Retinas, 127, 289
Cerebellar, Anterior-inferior, 131,
152
Posterior-inferior, 131, 152
Superior, 131, 152
Cerebral, Anterior, 127, 151
Middle, 127, 151
Posterior, 128, 152
Cervical, Ascending, 131, 152
Deep, from Sup. Intercostal, 132
Superficial, 131, 152
Transverse, 131, 152
Choroid, Anterior, 128, 151, 283
Posterior, 128, 152
Ciliary, Anterior, 127, 290
Long, 127, 290
Short, 127, 290
Circle of Willis, 128, 151
Artery, Circulus Major and Minor, 285
Circumflex, Femoral, Lateral, 142,
160
Medial, 142, 160
Humeral, Anterior, 133, 153
Posterior, 133, 153
Iliac, Deep, 141, 160
Superficial, 141, 160
Scapulae, 132, 153
Coccygeal, 140, 158
Cochlear, 312
Coeliac Axis, 137, 156
Colic, Left (sinistra), 138, 156
Middle (media), 138, 156
Right (dextra), 138, 156
Comes Nervi Ischiadici, 140, 158
Phrenici, 132, 152
Communicating, Cerebral, Ante-
rior, 127, 152
Posterior, 127, 151
of Palmar Arches, 135, 154
of Plantar Arch, 144, 162
Coronary, of Heart, 123, 148
of Lips, 125, 148
of Corpus Cavernosum, 130, 158
Cortical System of Brain, 128
Cremasteric, 141, 160
Cricq-thyro'd, 125, 148
Cystic, 138, 156
Dental, Inferior, 126, 150
Superior, 126, 150
Digital, Palmar Collateral, 135, 154
Plantar Collateral, 145, 162
Dorsalis Clitoridis, 140, 158
Hallucis, 144, 162
Indicis, 134, 153
Linguae, 125, 148
Nasi, 127, 151
Pedis, 143, 162
Penis, 140, 158
Pollicis, 134, 153
Scapulae, 132, 153
of Ear, 301, 312
of Elbow, 66, 145
Epigastric, Deep, 140, 160
Inferior, 140, 160
Superficial, 141, 160
Superior, 132, 152
Ethmoidal, Anterior, 127, 151
Posterior, 127, 151
of Eustachian Tube, 304
of Eye, 289
Facial, Deep, 126, 151
Superficial, 125, 148
Transverse, 126, 150
Femoral, Common, 141
Deep (profounda), 142, 160
Superficial, 141, 160
Fibular, 144, 162
of Foot, 143, 144
of Forearm, 133, 153
Frontal, from Ant. Cerebral, 127, 151
Mid. Cerebral, 127, 151
Ophthalmic, 127, 151
Temporal, 126, 150
Ganglionic, Antero-lateral, 127, 151
Postero-lateral, 128, 152
Antero-medial, 127,151
INDEX
4OI
Artery, Ganglionic, Postero-medial, 128,
152
System of Brain, 128
Gastric, 137, 150
Gastric, Left, 137, 156
Right, 137, 156
Gastricae Breves, 138, 156
Gastro-duodenal, 137, 156
Gastrp-epiploica Dextra, 137, 156
Sinistra, 138, 156
Genu Suprema, 142, 160
Gluteal, Inferior, 140, 158
Superior, 140, 160
Haemprrhoidal, Inferior, 140, 158
Middle, 139, 158
Superior, 138, 156
of Hand, 135
of Head, 124
of Heart, 119
Helicine, 371
Hepatic, 137, 138, 158, 340
Left, 138, 156
Right, 138, 156
of Hip-joint, 68, 145
Hyoid, from Lingual, 125, 148
from Superior Thyroid, 125, 148
Hypogastric, 139, 158, 160
Ileo-colic, 138, 156
Iliac, Circumflex, Deep, 141, 160
Superficial, 141, 160
Common, 139
External, 140, 160
Internal, 139, 158, 160
Ilio-lumbar, 140, 160
Incisor, 126, 150
Infra-orbital, 126, 150
Innominate, 124, 148
Intercostal, 136, 154
Anterior, 132, 152
Perforating, 132, 152
Superior, 132
Intercostalis Suprema, 132
Internal Auditory, 312
Interosseous, Common, 134
of Foot, 144, 162
of Forearm, 134, 154
of Hand, 134, 152
Ulnar, 134, 154
Intestines, 333, 336
Intestini Tenuis, 138, 156
of Iris, 285
of Kidney, 364
of Knee, 69, 143, 145, 162
Labial, Coronary, 125, 148
Inferior, 125, 148
Labiales, 125
of Labyrinth, 312
Lacrimal, 127, 151
Laryngeal, Inferior, 131, 152
Superior, 125, 148
of Larynx, 354
Lateralis Nasi, 125, 148
Lenticulo-striate (ant.-lat. gang-
lionic), 127
Lienal, 138, 156
Lingual, 125, 148
Dorsal, 125, 148
of Liver, 341
20
Artery, of Lower Extremity, 141
Lumbar, 138, 156, 160
of Lungs, 359
Magna, 153
Malleolar, Lateral, 143
Medial, 143
Mammary, External, 132
Internal, 131, 152
of Mammary Gland, 384
Mandibular (inf. dental), 126, 150
Masseteric, 126, 150
Mastoid, 125, 150
Maxillary, External, 125, 148
Internal, 126, 150
Median, 134
Mediastinal, 132, 152
Posterior, 136, 154
of Membrana Tympani, 299
Meningeal, Anterior, 127, 151
Middle, 126, 150
from Occipital, 125, 148
from Pharyngeal, 125, 150
Posterior, 131, 152
Small, 126, 150
from Vertebral, 131, 152
Mental, 126, 150
Mesenteric, Inferior, 138, 156
Superior, 138, 156
Metacarpal, 134, 153
Metatarsal, 144, 162
Musculo-phrenic, 132, 152
Mylo-hyoid, 126, 150
Nasal, Dorsal, 127, 151
Lateral, 125, 148
from Ophthalmic, 127, 151
of Nasal Fossae, 279
of Neck, 124
of Nose, 279
Nutrient of Clavicle, 131, 152
of Femur, 142, 160
of Fibula, 144, 162
of Humerus, 133, 153
of Tibia, 144, 162
Obturator, 139, 158, 389
Occipital, 125, 148
CEsophageal, 131, 136, 152, 154
of (Esophagus, 323
Ophthalmic, 127, 151
Orbital, 127, 151
Ovarian, 138, 156
of Ovaries, 383
Palatine, Ascending, 125, 148
Descending, 126, 150
Inferior, 125, 148
Posterior, 126, 150
Palmar (volar) Arch, Deep, 136
Superficial, 135
Recurrent, 134, 153
Palpebral, 127, 151
of Pancreas, 344
Pancreaticae magnae, 138
Parvae, 138
Pancreatico-duodenal, Inferior,
138, 156
Superior, 137, 156
Parietal, 126, 151
Parieto- temporal, 127. 151
of Parotid Gland, 126, 316
402
INDEX
Artery, of Pelvis, 139
of Penis, 372
Perforating, Anterior Intercostal,
132, 152
of Foot, 145, 162
of Hand, 134, 153
of Thigh, 142, 1 60
Pericardiac, 132, 152
Pericardia!, 136, 15,1
Pericardio-phrenic, 132
of Pericardium, 118
Perinaeal, Superficial, 140, 158
Transverse, 140, 158
of Perineum, 140
Peroneal (fibular), 144, 162
Pharyngeal, 125, 126, 150
Ascending, 125, 150
of Pharynx, 322
of Pia Mater, 182
Plantar, Lateral, 144, 162
Medial, 14.4, 162
Popliteal, 143, 162
Postero-lateral Ganglionic, 128, 152
Postero-medial Ganglionic, 128, 152
Prevertebral, 125, 150
Princeps Cervicis, 125, 148
Polhcis, 134, 153
Profunda Brachii, 133, 153
Cervicis, 132
Femqris, 142, 160
Inferior (arm), 133, 153
Penis, 140, 158
Superior (arm), 133, 153
of Prostate Gland, 370
Pterygoid, 126, 150
Pterygo-palatine, 126, 150
Pubic, 141, 160
Pudendal, 139, 158
Pubic, External, Deep, 142, 160
Superficial, 141, 160
Internal, 139, 158
Pulnumary, 122, 147
Pyloric, 137, 156
Radial, 133, 153
Radialis Indicis, 134, 153
Radial Recurrent, 133, 153
Ranine, 125, 148
Receptaculi, 127, 151
Recurrent, Palmar (volar), 134,153
Radial, 133, 153
Tibial, Anterior, 144, 162
Posterior, 144, 162
Ulnar, Anterior, 134, 154
Posterior, 134, 154
Volar (palmar), 134, 153
Renal, 138, 156
Rete Carpi Dorsale, 135
Volare, 135
of Retina, 286
Sacral, Lateral, 140, 160
Middle, 138, 156
Scapular, Circumflex. 132, 153
Dorsal, 132, 153
Posterior, 131, 152
Transverse, 131
Sciatic, 140, 158
of Shoulder-joint, 65, 145
Sigmoid, 138, 156
Artery, Spermatic, 138, 156
of Spermatic Cord, 377
Spheno-maxillary, 126, 150
Spheno-palatine, 126, 150
Spinal, Anterior, 131, 152
Lateral, 131, 152
Posterior, 131, 152
of Spleen, 349
Splenic, 138, 156
Sternal, 132, 152
Sterno-mastoid, 125, 148
of Stomach, 330
Stylo-mastoid, 125, 150
Subclavian, 130
Subcostal, 136
Sublingual, 125, i/>8
Submandibular, 125, 148
Submental, 125, 148
Subscapular, 132, 153
Superficialis Volas, 133, 153
Supra-orbital, 127, 151
Supra-renal, 138, 156
of Supra-renal Gland, 365
Supra-scapular, 131, 152
Sural, 143
Tables of the Arterial System, 147
Tarsal, 144
Temporal, Deep, Anterior, 126, 150
Posterior, 126, 150
Middle, 126, 150
Superficial, 126, 150
of Testicle, 375
of Thigh, 141, 1 60
Thoracalis Lateralis, 132
Suprema, 132
Thoracic, Acromio, 132, 153
Alar, 132, 153
Axis, 131, 153
Long, 132, 153
Superior, 132, 153
Thoraco-acromial, 132
of Thymus Gland, 346
Thyroid. Axis, 131
Inferior, 131, 152
Superior, 125, 148
of Thyroid Gland, 346
Thyroidea Ima, 124
Tibial, Anterior, 143, 16^
Posterior, 144, 162
Recurrent, Anterior, 143, 162
Posterior, 143, 162
of Tongue, 275
Tonsillar, 125, 148
True, 314
of Tonsils, 314
of Trachea, 356
Tracheal, 131, 152
Transversalis Colli, 131, 152
Scapulae, 131
True Tonsillar, 314
Truncus Thyreo-cervicalis, 131
of Trunk, 136
Tympanic from Ascending
Pharyngeal, 125, 150
from Internal Carotid, 127, 151
Maxillary, 126, 150
of Tympanic membrane, 299
of Tympanum, 302
INDEX
403
Artery, Ulnar, 134, IS4
Carpal, 134, 154
Collateral, 133
Interosseous, 134
Recurrent, Anterior, 134, 154
Posterior, 134, 154
of Upper Extremity, 130
Urethral, 140
Uterine, 139, 158
of Uterus, 382
of Vagina, 379
Vaginal, 139, 158
Vasa Brevia, 138, 156
Intestinales, 138
Intestini Tenuis, 138, 156
Vasorum, 122
of Vas Deferens, 139, 158
Vertebral, 131, 152
Vesical, Inferior, 139, 158
Middle, 139, 158
Superior, 139, 158
of Vesiculae Seminales, 377
Vidian, 126, 150
Volar, Superficial, 133, 153
Willis, Circle of, 128, 251
Zygomatico-orbital, 126
Arthrodial joints, 59
Articulations, 59
Acromio-clavicular, 65
Ankle, 71
Astragalo-navicular, 72
Atlanto-axial, 58
Atlanto-epistrophica, 61
Calcaneo-astragaloid, 72
Calcaneo-cuboid, 72
Calcaneo-navicular, 72
Carpal, 50, 67
Carpo-metacarpal, 68
Chondro-sternal, 62
Costo-chrondal, 62
Costo-transverse, 62
Costo-vertebral, 62
Elbow, 66
Hip, 68
Intercarpal, 67
Interchondral, 62
Knee, 69
Metacarpo-metacarpal, 68
Metatarso-metatarsal, 73
Motion in, 60
Occipito-atlantal, 62
Occipito-axial, 62
Phalangeal of Foot, 73
of Hand, 68
Pubic, 64
Radio-carpal, 67
Radio-ulnar, 66
Sacro-C9ccygeal, 63
Sacro-iliac, 64
Sacro-ischiatic, 64
Sacro- vertebral, 63
Scapulo-clavicular, 65
Shoulder, 65
Sterno-clavicular, 64
Structure of, 60
Tarsal, 57, 72
Tarso-metatarsal, 72
Ternporo-mandibular, 6q
Articulations, Tibio-fibular, 71
of the Trunk, 60
Vertebral, 61
Arytenoid Cartilages, 351
Astragalus (talus), 57
Atic, 300
Atlas, 6
Atrium Meatus Medii Nasi, 278
Tympani, 300
Auricle of Ear, 297
of Heart, 119
Auris Externa, 296
Interna, 304
Media, 300
Axis, 7
Caeliac, 137, 156
Thyroid, 131, 152
Axis-cylinders, 177
Axones, 177
Azygos, 3
BAND, Bellinger's, 285
Naso-labial, 78
Bartholin, Duct of, 317
Glands of, 378
Basal Ganglia, 179
Base of the Brain, 186
, of the Skull, 41
Basi-hyal, 41
Basis Pedunculi Cerebri, 195
Bauhin, Valve of, 334
Bell, Sir Charles, Nerve of, 229, 256
Bertin, Columns of, 361
Bladder, Gall, 193 - *J f J
Urinary, 365
Blandin, Glands, of, 274
Blastema, 4
Blood- vascular System, 118
Body or Bodies, Aortic, 345
Carotid, 345
Chromaphil, 345
Ciliary, 283
Coccygeal, 349
Gemculate, 193
Malpighian, 349, 361
Mammillary, 188
Olivary, 209
Perinseal, 395
Pineal, 194
Pituitary, 186
Quadrigeminal, 202
Restiform, 207, 209
Vitreous, 287
Wolffian, 383
Bone or Bones, i
Astragalus (talus), 57
Atlas, 6
Axis (epistropheus), 6
Calcaneus, 57
Cancellous Bones, 2
Capitate (Magnum), 51
Cavities of, 3
Clavicle, 45
Classification of, i
Coccyx, ii
Composition of, 3
Costae, 8
Coxae or Coxal , 1 1
404
INDEX
Bones, Cuboid, 57
Cuneiform (carpal), 51
(tarsal), 57
Eminences of, 3
Enumeration of, i
Epistrqpheus (axis), 6
Ethmoid, 26
Femur, 52
Fibula, 55
Flat Bones, 2
Frontal, 14
Hamate (unciform), 51
Histology of Bone, 3
Humerus, 47
Hyoid, 41
Ilium, 13
Incus, 301
Innominate (coxal), II
Irregular Bones, 2
Ischmm, 13
Lacrimal, 29
Long Bones, i
Lunate (Semilunar), 51
Malar, 30
Malleus, 301
Mandible, 33
Marrow of Bones, 4
Maxilla, 27
Medullated Bones, i
Metacarpals, 51
Metatarsals, 58
Multangular, Great, 51
Small, 51
Nasal, 27
Navicular (carpal), 51
(tarsal), 57
Occipital, 17
Orbicular, 301
Os Calcis, 57
Os Capitatum, 51
Os Coccygis, 1 1
Os Coxae, n
Os Hamatum, 51
Os Innominatum, n
Os Lunatum, 51
Os Magnum, 51
Os Multangulum Majus, 51
Minus, 51
Os Nayiculare, 51
Os Orbiculare, 301
Os Triquetrum, 51
Ossa Suturarum, 40
Ossification of Bones, 4
Palate, 31
Parietal, 16
Patella, 54
Pectineal, 14
Peroneal, 55
Petro-mastoid, 19
Phalanges of Foot, 58
of Hand, 52
Pisiform, 51
Prominences of Bones, 3
Pubic, 14
Radius, 49
Ribs (costse), 18
Sacral, 10
Scaphoid (carpal), 51
Bones, Scaphoid (tarsal), 57
Scapula, 45
Semilunar, 51
Sesamoid, 3
Short Bones, i
Squamous, 19
Stapes, 301
Sternum, 8
Structure of Bone, 4
Talus, 57
Temporal, 19
Tibia, 54
•Trapezium, 51
Trapezoid, 51
Triquetral (cuneiform), 51
Turbinal, 32
Tympanic, 19
Ulna, 48
Unciform, 51
Unclassified Bones, 3
Vertebrae, 5
Vomer, 33
Wormian, 3, AO
Zygomatic, 30
Bowman's Capsule, 361
Glands, 279
Muscle (ciliary), 284
(cochlear), 309
Brachia Conjunctiva, 201, 207
Pontis, 204, 207
Brain, 178
Abdominal, 240
Basal Ganglia of, 179
Cerebellum, 206
Cerebrum, 183
Convolutions of, 185
Cortex of, 179
Development of, 178
Diencephalon, 178
Divisions of, 178, 182
Fissures of, 184
Gray Matter of, 179
Hind-brain, 203
Hypophysis Cerebri. 186
Island of Reil, 183
Isthmus Cerebri, 194
Isthmus Rhombencephali, 178, 203
Lobes of, 183
Medulla Oblongata, 208
Meninges of, 180
Mesencephalon, 178, 194
Metencephalon, 178, 203
Mid-brain, 178, 194
Myelencephalon, 178, 208
Points on Under Surface, 186
Pons Varolii, 203
Prosencephalon, 178
Rhombencephalon, 192
Telencephalon, 178
Thalamencephalon, 192
Under Surface of, 186
Weight of Average Brain, 182
White Matter of, 179
Ventricles of, 189
Vesicles of, 178
Breasts, 383
Broca's Area or Convolution, 185
Bronchi, 355
INDEX
405
Bruch's Membrane, 283
Brunner's Glands, 333
Buccae, 312
Buck's Fascia, 393
Buds, Taste, 274
Bulb of Corpus Spongiosum, 372
Olfactory, 183
Spinal, 208
Urethra], 369
Bulbus Oculi, 280
Vestibuli, 378
Bulla Ethmoidalis, 277
Bundle, Ground, 215
Posterior Longitudinal, 200
Burns' Ligament, 390
Bursa Omentalis, 325
Pharyngea, 321
Bursae of Knee-joint, 71
Calamus Scriptorius, 211
Calcaneus, 57
Calcar Avis, 191
Calcar Femorale, 53
Calices of Kidney, 361
Cameras Oculi, 287
Camper's Fascia, 108, 385
Canal, or Canalis, Adductor, no, 142
Alcock's, 392
Alimentary, 312
Anal, 335
of Arnold's Nerve, 21
Carotid, 20
Central of the Cord, 214
Centralis Modioli, 306
Cervicis Uteri, 380
Condyloideus Posterior, 18
Crural, 388
Dental, 27
Facial, 220, 225
Femoral, 388
Haversian, 4
of Huguier, 19
Hunter's, no, 142
Hyaloid, 288
Hypoglossi, 1 8
Infra-orbital, 28
Inguinal, 385
of Jacobson's Nerve, 21
Lacrimal, 295
of Laxator Tympani, 19, 43
Malar, 30, 36
Mandibular, 34
of the Modiolus, 306
of Nuck, 381
Palatine, 28
Petit's, 288, 289
Pharyngeal, 32
Pterygoideus, 25
Ptery go-palatine, 28
Reuniens, 307, 308
Sacral, n
of Schlemm, 282
Semicircular, 305, 308
Spheno-palatine, 32
Spiral of Cochlea, 306
Stilling's, 288
for Tensor Tympani, 301
Canal, Vidian, 25
Zygomatico-facial, 30, 36
Zygomatico-temporal, 36
Canaliculi Dentales, 319
Lacrimal, 295
Canthus (eye), 293
Capillaries, Biliary, 340
Blood, 122
Capitellum Humeri, 48
Capsule or Capsula, Bowman's, 361
External, 192
of Glisson, 340
Glomeruli, 361
Internal, 192
Lentis, 288
Tenon's, 280
Supra-renal, 364
Caput Gallinaginis, 368
Cardia, 329
Carpus, 50
Cartilage or Cartilage, 60
Arytenoid, 351
Corniculata, 352
Cricoid, 351
Cuneiform, 352
Epiglottica, 352
of Larynx, 350
Santorini's, 352
Thyroid, 350
Triticea, 353
Varieties of, 60
Wrisberg's, 352
Carunculae Humenales, 378
Lacrimal, 295
Myrtiformes, 378
Cauda Equina, 216
Cavity or Cavum —
Abdominal, 323
Acetabular, 12
Cotyloid, 12
Dentis, 318
Glenoid, 47
Omental, 325
Oris, 312
Pelvic, 391
Peritonaei, 325
Pulp, 318
Septi Pellucidi, 191
Sigmoid of Radius, 50
of Ulna, 49
Subarachnoidalis, 181
Subdurale, 181
Tympanic, 300
Uteri, 380
Cells, Air, 359
Auditory, 310
Claudius', 310
Deiters', 310 .
Ethmoidal, 26
Golgi's, 176, 208
Hair, 307, 310
Hensen's, 310
Hepatic, 340
Mastoid, 20
Nerve, 176
Olfactory, 278
Purkinje's, 176, 208
Reticular, 349
406
INDEX
Cells, Sustentacular, 349
Cement, 319
Cerato-hyal, 41
Cerebellum, 206 (see Brain)
Cerebro-spinal System, 175
Cerebrum, 179 (see Brain)
Cervic Penis, 372
Cervix Uteri, 380
Chambers (camerae) of the Eye, 287
Chiasm, Optic, 292
Chorda Tympani, 220, 248, 276
Chordae Tendinae, 120
Choroid, 283
Plexus, 190, 211
Chromaffin System, 344
Chromaphil System, 344
Cilia, 293
Ciliary Body, 283
Cingulum, 180
Circle of Willis, 128, 151
Circulation, Collateral, 146
Circulus Major of Iris, 285
Minor of Iris, 285
Venosus, 384
Cisterna Chyli, 172
Cerebello-medullaris (magna), 182
Inter-peduncularis, 182
Magna (cerebello-medullaris) , 182
Clarke's Column, 210, 216
Claudius' Cells, 310
Claustrum, 192
Clava, 198
Clavicle, 45
Clinoid, 3
Clitoris, 378
Clivus Monticuli, 207
Cloquet's Fascia, 389
Coccygis, ii
Coccyx, ii
Cochlea, 306, 309
Collar-bone, 45
Collateral Circulation, 146
Colics' Fascia, 392
Colliculi (quadrigemina), 202
Colliculus Nervi Facialis, 212
Optici, 286
Semmalis, 368
Colloid, 346
Collum Glandis, 372
Colon, 334
Column or Columns —
Antero-lateral of Cord, 214
Bertin's, 361
Burdach's, 198, 210, 215
Clarke's, 210, 216
Coil's, 198, 210, 215
Lateral of Medulla, 209
Posterior of Cord, 214
Vesicular (Clarke's), 216
Postero-lateral of Cord, 214
Postero-median of Cord, 214
of Spinal Cord, 213
of Vagina, 379
Columnae Carneae, 120, 122
Rugarum, 379
Commissura or Commissure —
Anterior (yhite) of 3d Ventricle,
192
Commissura, Gray (middle) of 3d Ven-
tricle, 193
Gudden's, 194, 292
Labiorum Pudendi, 377
Meynert's, 292
Middle (gray) of 3d Ventricle, 193
Optic, 1 86, 292
Palpebrarum, 293
Posterior (white) of 3d Ventricle, 193
Concha or Conchae —
Auriculas, 297
Nasalis, 26, 32
Sphenoidal, 24
Conductor Sonorus, 212
Condyle, 3
Condyloid Articulations, 59
Confluens Sinuum, 165
Coni Vasculosi, 374
Conjoined Tendon, 95
Conus Arteriosus, 120
Elasticus, 353
Convolution of Broca, 185
Convolutions of the Cerebrum, 185
Cooper's (Sir Astley) Fascia, 390
Cor, 118
Coracoid, 3
Cord, Gangliated, 237
Spermatic, 376
Spinal, 213
.Vocal, 353
Conum, 270, 271
Cornea, 282
Cornicula Laryngis, 352
Cornua of Hyoid, 41
Uteri, 380
Ventricular, 190
Corona Glandis, 372
Radata, 196
Coronoid, 3
Corpora Albicantia, 188
Amylacea, 194
Cavernosa, 371
Geniculata, 193
Mammillaria (albicantia), 188
Quadrigemina (colliculi), 202
Restiformes, 207, 209
Corpus Albicans, 383
Callosum, 190
Cayernosum Urethras, 371
Ciliare, 283
Dentatum, 209
Fimbriatum, 190, 191
Highmorianum, 374
Luteum, 383
Mammae, 384
Medullare, 206
Pineale, 194
Striatum, 191
Trapezoideum, 204
Uteri, 380 .
Vitreum, 287
Corpuscles, Cprneal, 282
Ganglionic, 176
Pacinian, 272
Tactile, 272
Cortex, Cerebellar, 208
Cerebral, 179
Renal, 361
INDEX
407
Corti, Organ of, 309
Cortical System, 345
Costae (ribs), 8
Cotyloid. 3
Cavity, 12
Notch, 12
Coverings of Brain, 180
of Femoral Hernia, 390
of Inguinal Hernia, 388
of Testicles, 373
of Spinal Cord, 213
Cowper's Glands, 371
Coxal or Hip-bone, n
Crest, Conchal, 27, 31
of Ilium, 13
Infra-temporal, 24
Inter-trochanteric, 53
Nasal, 29
Nuchal, 17
of Pubis, 17
Sphenoidal, 23
Tibial, 55
Turbinal, 27, 31
Cribriform Fascia, 108, 390
Plate, 26
Cricoid Cartilage, 351
Crista Falciformis, 311
Galli, 26
Transversa, 311
Urethrae, 368
Vestibuli, 305
Crucial Anastomosis, 146
Ridge, 1 8
Crura of Abdominal Ring, 386
Cerebri, 195
Clitoridis, 378
of Diaphragm, 95
of Penis, 371
Crus Commune, 306
Crusta Cerebri, 195
Petrosa, 319
Crypts, of Lieberkuhn, 332
Cuboid, 57
Culmen Monticuli, 207
Cuneus, 186
Cupola Cochleae, 306
Cushion, Pharyngeal, 321
Cuticle, 268
Cuticuta Dentis, 319
Cutis Vera, 270
DARTOS, 373
Darwin's Tubercle, 297
Decussation, Inferior Pyramidal, 209
Motor, 209
Sensory, 198
Superior Pyramidal, 198
Deiter's Cells, 310
Dendrites, 177
Dentes, 317
Dentine, 318
Derma, 270
Dermatology, I
Descemet's Membrane, 282
Diaphragm, 94
Urogenital, 393
Diaphragma Sellae, 181
Diaphysis, 9
Diarthrosis, 59
Diclive, 207
Diencephalon, 178, 192
Discus Proligerus, 383
Disk, Intervertebral, 61
Optic, 286
Diverticulum Ilei, 331
Meckel's, 331
Dollinger's Band, 285
Dorsum Sellae, 23
Douglas' Pouch, 327
Semilunar Fold, 96
Drum of the Ear, 300
Drum-head, 298
Duct, Ducts, or Ductus —
Aberrans, 373
Arteriosus, 123
Bartholin's, 317
Biliary, 342
Cochlearis, 307
Communis Choledochus, 342
Cowper's, 368
Cystic, 343
Deferens, 375
Ejaculatory, 368, 376
Endo-lymphaticus, 308
Gartner's, 383
Hepatic, 342
Lactiferi, 384
Lymphatic, 172
Lymphaticus Dexter, 172
Nasal, 28, 296
Naso-lacrimal, 296
Pancreatic, 344
Parotideus, 316
Prostatic, 370
Rivinius", 316
Santorini's, 344
Semicirculares, 307, 308
Stenson's, 316
Sublinguales Minores, 316
Sublingualis, 316
Submaxillaris, 316
Thoracic, 172
Wharton's, 316
Wirsung's, 344
Utriculo-saccularis, 308
Ductless Glands, 344
Duodenum, 331
Dural Sinuses, 164, 165
Dura Mater Cerebri, 180
Spinalis, 213
EAR, 296
External, 297
Internal, 304
Middle, 300
Elbow-joint, 66
Eleidin, 270
Eminence, Frontal, 14
Hypothenar, 106
Malleolar, 298
Nasal, 14
Eminence Parietal, 16
Pectineal, 14
Thenar, 196
Eminentia Articularis, 19
Cinprea . v i •
INDEX
Eminentia Collateralis, 191
Inter-cpndyloidea, 54
Pyramidalis, 301
Saccularis, 186
Teres, 212
Enamel, 319
Enarthrosis, 59
End-bulbs of Krause, 177, 272
Endocardium, 118
Endolymph, 304
Endomysmm, 74
Endoneurium, 177
End-organs of Nerves, 177
Endosteum, 4
Ensiform (xyphoid), 8
Epidermis, 270
Epididymis, 373
Epigastric Region, 324
Epiglottis, 352
Epineurium, 177
Epiphysis, 3
Cerebri, 194
Epistropheus (axis), 6, 7
Equilibration, Organ of, 309
Ethmoid, 26
Eustachian Tube, 303
Eye, 280
Eyebrows, 293
Eyelashes, 293
Eyelids, 293
Eye-socket (orbit), 35
Excavatio Papillae Nervi Optici, 286
Recto-uterina, 327
Recto- vesicalis, 327
Vesico-uterina, 327
Extension, Anterior of Ischio-rectal
Fossa, 394
FACET, 3
Fallopian Tubes, 382
Fallopius, Aquseduct of, 220, 225
Hiatus of, 20
Falciform Process, 390
Falx Aponeurotica Inguinalis, 95
Cerebelli, 181
Cerebri, 181
Fascia, Anal, 392
Bicipital, 133
Buck's, 393
Bulbi Oculi, 280
Camper's, 108, 385
Cloquet's, 389
Colles', 392
Cooper's, 390
Cremasteric, 386
Cribriform, 108, 390
Deep, 74
Dentate, 191
Diaphragmatis Urogenitalis, 393
Dorsal, 90
Infundibuliform, 385
Iliac, 107
Intercolumnar, 386
Ischio-rectal, 392
Lata, 1 08, 199
Lumbar, 90
Fascia, Lumbo-dorsal, 90
Naso-labial Band, 78
Obturator, 391
Palmar, 105
Parotid, 315
Parotideo-masseteric, 315
Pelvic, 391
Perinaeal, Deep, 393
Superficial, 392
Pharyngo-basilar, 322
Plantar, 115
Recto- vesical, 391
Scarpa's, 108, 390
Spermatic, 386
Superficial, 74
Trartsversalis, 107, 390
Triangular, 387
Fasciae, 74
of the Back, 90
of the Foot, 115
of the Hand, 105
of the Pelvis, 391
of the Perinaeum, 392
of the Thigh, 108
Fasciculus, see also Tract
Anterior Cerebro-soplina, 96, 214
Cerebello-olivary, 211
Cerebro-spinalis Anterior, 196, 214
Lateralis, 196, 214
Crossed Pyramidal, 196, 214
Cuneatus (Burdach's), 198, 210, 215
Direct Cerebellar, 210
Direct Pyramidal, 196, 214
Dorsal Spino-cerebellar, 210
Fillet, 198
Flechsig's, 210
Geniculate, 196
Geniculate, 196
Gower's, 205
Gracilis (Coil's column), 198, 210,
215
Inferior Longitudinal, 180
Lateral Cerebro-spinal, 196, 214
Lemniscus, 199
Lemniscus, (fillet), 198
Medial Lemniscus, 198
Longitudinal, 200
Meynert's, 292
Olivary, 202
Olivo-cerebellar, 210
Perpendicular, 180
Posterp-lateral, 215
Proprii, 215
Proprius Anterior, 215
Dorsalis, 215
Posterior, 215
Ventralis, 215
Retroflexus (Meynert's), 29
Rolando's, 209
Rubro-Spinal, 201
Solitary, 211, 221
Spino-cerebellar, Anterior, 205, 210,
214
Dorsal, 210, 215
Sulco-marginal, 199
Superficial Ventro-lateral (Gower's)
295, 206
Superior Longitudinal, 180
INDEX
409
Fasciculus, Teres, 205
Tri-neural, 211
Tiirck's, 196
Uncinate, 180
Ventral Cerebro-spinal, 196
Longitudinal, 199
Fauces, 314
Femur, 52
Fenestra Cochleae, 21, 300
Ovalis, 300
Rotunda, 300
Vestibuli, 21, 300
Ferrein's Pyramids, 362
Fibrae Propriae, 207
Fibres, Arcuate of Cerebellum, 208
of Medulla, 210
Association, 180
Commissural, 180
Medullated, 17?
Miiller's, 286
Nerve, 177
Non-medullated, 177
Peduncular, 179, 207
Projection, 179, 192
Transverse, 180
Fibro-cartilage, 60, 70
Fibula, 55
Fillet, Lateral, 199
Medial, 198
Filum Terminale, 213
Fimbria Ovarica. 382
Fimbriae Tubae Uterinas, 382
Fissure, Auricular, 21, 43
Ethmoidal, 41
Glaserian, 19, 43
Orbital, 25, 36, 39, 41
Palpebral, 293
Pterygo-maxillary, 39
Rolando's, 184
Sphenoidal, 25, 36, 41
Spheno-maxillary, 37, 39
Squamo-tympanic, 44
Sylvius', 184
Fissures of Cerebellum, 206
of Cerebrum, 184
of Liver, 337
of Spinal Cord, 213
Flexure, Sigmoid, 334
Flocculus, 207
Fluid. Cerebro-spinal, 182
Fold, Aryteno-epiglottidean, 352
Glosso-epiglottidean, 353
Palpebral, 295
Semilunar, 295
of Douglas, 96
Folium Cacuminis, 207
Folliciles, Hair, 271
Simple, 332, 335
Folliculi Oophori Vesiculosi, 383
Fontana's Spaces, 282
Fontanelles, 40
Foot, 56
Foramen for Arnold's Nerve, 21, 43
Caecum, 15, 43, 274
Carotid, 43
Condylar, 18, 42
Costo-transverse, 6
Epiploicum, 326
Foramen for Ethmoidal, 16, 37, 41
Incisive, 29, 42
Infraorbital, 28
Interventricular, 190
Intervertebral, 5
for Jacobson Nerve, 21, 43
Jugular, 42
of Ke
[ey and Retzius, 211
Lacerum Anterius, 25, 36, 41
Medium, 41
Posterius, 17, 42
Magendie's, 182, 211
Magnum, 17, 42
Mandibular, 34
Mastoid, 20, 42
Mental, 31
Munro's, 190
Obturator, 12
Olfactory, 38, 41
Ovale, 24, 41
Optic, 25, 37, 41
Orbital, 24
Palatine, 32, 42
Parietal, 16
Pterygo-palatine, 42
Rotundum, 24, 41
Sacral, n
Scarpa's, 29, 42
Singulare, 311
Spheno-palatine, 31
Spinal, 6
Spinosum, 24, 41
Stenson's, 29, 42
Stylo-mastoid, 21, 43
Supraorbital, 14
Suprascapular, 45
Thyroid, 12
Vertebrale, 6
Winslow's, 326
Foramina at the Base of the Skull, 41
Interventricularia, 190
Olfactory, 41
Orbital, 35
Spheno-maxillary, 42
Thebesii, 119
Venarum Minimarum, 119
Forearm, 48
Formatio Reticularis, 211
Fornix Cerebri, 190
Conjunctivas, 295
Fossa of the Auricle, 297
Canine, 28
Cochlearis (recessus), 305
C9ronoid, 48
Digastric, 20, 34
Digital (femoris), 53
(testis), 374
Duodenal, 327
Duodeno-jejunal, 327
Floccular, 22
Glenoid, 19
Hypophyses, 22
Ileq-colic, 328
Incisive, 28, 34
Incudis, 301
Infraspinous, 45
Inguinal, 388
Intercondylar, 55
4io
INDEX
Fossa of the Intersigmoid, 328
Ischio-rectal, 394
Jugular, 1 8, 21
Lacrimal, 15, 36
Mandibular, 19
Nasal, 37, 277
Navicularis Auriculae, 297
Penis, 369
Pudendi, 377
Olecranon, 48
Ovalis Cordis, 108, 119
Femoralis, 389
Patellaris, 288
Pericascal, 328
Perinaeal, 393
Peritoneal, 327, 388
Pterygoid, 25
Radial, 48
Rosenmuller's, 322
Scaphoid, 25
Spheno-maxillary, 39
Spheno-palatine, 39
Sublingual, 34
Submandibular, 34
Subscapular, 45
Supraspinous, 45
Supra-tonsillaris, 314
Temporal, 38
Triangularis Auriculae, 297
Trochanteric, 53
Venae Cavae Hepatis, 338
Vesicae Felleae, 338
Zygomatic, 39
Fossae, Inguinal, 388
Nasal, 37, 277
Perinaeal, 393
Retro-peritoneal, 327
of the Skull, 41, 42
Fourchette, 377
Fovea Articularis, 6
Centralis, 285
Hemispherica, 305
Inferior of 4th Ventricle, 212
Semi-elliptica, 305
Superior of dth Ventricle, 212
Fraenulum Cerebelli, 207
Praeputii, 372
Fraenum Linguae, 223
Frenula Oris, 312
Frontal Bone, 14
Sinuses, 15
Fundus Oculi, 285, 286
Uteri, 380
Funiculus, Antero-lateral of Cord,
213
Cuneatus of Medulla, 210
Gracilis of Medulla, 210
Lateralis of Medulla, 209
Posterior of Cord, 213, 215
Postero-lateral of Cord, 214
Postero-median of Cord, 214
Rolando's, 209
Teres, 205
Solitarius, 211, 221
GALL-BLADDER, 343
Gartner's Duct, 383
Ganglia, 177
Ganglia, Basal, 179
Cervical, 237, 268
of the Cranial Nerves, 223
Lumbar, 238, 268
of Ninth Cranial Nerve, 226
Pelvic, 238
Sacral, 268
Semilunar, 240
Spinal, 216, 226
Sympathetic, 268
of Tenth Cranial Nerve, 226
Thoracic, 237, 268
Gangliated Cord of Sympathetic, 237
Ganglion, Arnold's, 224
Bochdalek's, 236
Cardiac of Wrisberg, 239
Carotid, 236
Cerebellar, 208
Ciliary, 224
Coccygeal, 238, 268
Cceliac, 240
Diaphragmatic, 240
Gasserian, 223
Geniculate, 225
Habenulae, 194
Impar, 236, 268
Inferius, 226
Jugular, 226
Jugulare, 226
Lenticular, 224
Meckel's, 224
Nodosum, 226
Ophthalmic, 224
Otic, 224
Petrous, 226
Ribes', 236, 237. 268
of Root of Tenth Nerve, 226
Scarpa's, 311
Semilunar, 223, 240
Spheno-palatine, 224
Spinal, 216
Spirale, 311
Submandibular, 225
Submaxillare, 225
Superius, 226
of Trunk of the Tenth Nerve, 226
Valentines', 236
Wrisberg's, 239
Gasser's Ganglion, 223
Genesiology, i
Geniculate Bodies, 193
Gimbernat's Ligament, 387
Gingivae, 317
Girdle, Pelvic, 44
Shoulder, 44
Gladiolus, 8
Gland or Glands —
Adrenal, 364
Aortic Bodies, 345
Axillary, 173
Barth9lin's, 378
Blandin's, 274
Bowman's, 279
Bronchial, 175
Brunner's, 333
Bulbp-urethral, 371
Cardiac, 330
Carotid Bodies, 345
INDEX
411
Giands of Chromaffin System, 344
of Chromaphil System, 344
Ciliary, 293
Coccygeal, 349
Cceliac, 174
of Cortical System, 345
Cowper's, 371
Ductless, 344
Duodenal, 333
Gastric, 329, 330
Glomus Caroticum, 345
Coccygeum, 349
Ebner's, 274
Entodermal, 345
Fundus, 330
Haemal, 172
Lymph, 172
Intestinal, 332, 335
Kidney, 360
Lacrimal, 295
Lien, 275
Littr6's, 369
Liver, 336
Lumbar, 174
Lymphatic, 171
Mammary, 383
Mediastinal, 175
Meibomian, 294
Mesenteric, 175
Moll's, 293
Mucous, 315
Nuhn's, 274
CEsophageal, 323
Ovary, 382
Pancreas, 343
Paraganglia, 345
Parathyroid, 346
Parovarium, 383
Partiod, 315
Peyer's, 333
Phaerochrome, 344
Pineal, 194
Pituitary, 186
Prostate, 370
Pyloric, 330
Racemose Serous, 274
Rosenmuller's, 295
Salivary, 315
Sebaceous, 271, 273
Seminal, 372
Serous, 274
Smegma, 372
Solitary, 333
Spleen, 375
Sublingual, 316
Submandibular, 316
Submaxillaris, 316
Sudoriferous, 271, 273
Supra-renal, 364
Sweat, 270, 273
Testicle, 372
Thymus, 347
Thyroid. 345
Tracheal, 355
Tonsil, 314
Tyson's, 372
Urethral, 369, 370
of Vascular System, 348
Glands, Vestibulares, 378
Glans Clitoridis, 378
Penis, 372
Glaserian Fissure, 19, 43
Glenoid, 3
Glisson's Capsule, 3.36
Globus Major Epididymis, 273
Minor Epididymis, 273
Glomus Caroticum, 345
Coccygeum, 349
Glottis, 353
Golgi's Cells, 176, 208
Gomphosis, 59
Graafian Vesicles, 383
Granulationes Arachnoideales, 181, 182
Gray Matter (substantia grisea), 176
of Aquaeduct of Sylvius, 202
of Cerebellum, 208
of Cerebrum, 179
of Medulla Oblongata, 209
of Pons Varolii, 204
of Spinal Cord, 215
Nervous Tissue, 176
Rami Communicantes, 227, 238
Groove, Alar, 24
Auriculo- ventricular, 118
Bicipital, 47
Infraorbital, 27
Intertubercular, 47
Interventricular, 118
Lacrimal, 29
Musculo-spiral, 47
Mylo-hyoid, 35
Naso:palatine, 33
Nervi Radialis, 47
Occipital, 20
Optic, 22
Pterygo-palatine, 24, 28
Gubernaculum Testis, 375
Gudden's Commissure, 194, 292
Gullet, 322
Gums, 317
Gyrus, see Convolution or Lobe
HABENULAR Ganglion, 194
Trigone, 194
Haemal Glands, 172
Lymph Glands, 172
Hair Cells, Auditory, 310
Hairs, 273
Olfactory, 279
Hamstrings, 112
Hamular, 3
Hamulus, 306
Hand, 50, 105
Hasner's Valve, 296
Haversian Canals, 4
Spaces, 4
System, 4
Head-plates, Auditory, 310
Heart, 118
Heel, 57
Helicotrema, 306
Helix, 297
Hemispheres, Cerebral, 183
Henle's Loops, 362
Hensen's Canal, 307
Cells. 307
412
INDEX
Hepar, 336
Hernia, 384
Femoral, 388
Coverings of, 390
Inguinal, 385
Coverings of, 388
Herophilus' Torcular, 18
Hesselbach's Triangle, 387
Key's Ligament, 390
Hiatus Canalis Facialis, 20
Falk>pii, 20, 42
Semilunaris, 277
Highmore (Nathaniel), Antrum of, 27
Hilton's Sac, 354
Hilum or Hilus of the Kidney, 360
of the Lung, 358
of the Spleen, 348
of the Supra-renal Gland, 364
Hind-brain, 203
Hip-joint, 68
Hippocampus Major i 191
Minor, 191
Horner's Muscle (tensor-tarsi), 75
Houston's Valves, 335
Huguier's Canal, 19, 300
Humerus, 47
Humor, Aqueous, 287
Hunter's Canal, no, 142
Hyal, Basi-, 41
Cerato-, 41
Stylo- (styloid process), 21
Thyro-, 41
Tympano- (vaginal process), 21
Hydatid's of Morgagni, 373, 382
Hyoid Pone, 41
Hymen, 378
Hypochondrium, 324
Hypogastrium, 324
Hypothalamus, 202
Hypothenar Eminence, 106
Hypophysis Cerebri, 186
ILEUM, 331
Iliac Regions, 324
Ilium, 13
Incisura Acetabuli, 12
Cerebelli, 206
Intertragica, 297
Marsupialis, 206
Radialis, 49
Rivini, 298
Semilunaris, 49
Thyroidea, 350
Incus, 301
Infundibula of the Kidney, 361
Infundibulum, 26, 277
Cerebri, 186
Cochleas, 306
Nasal, 277
Tubae, Uterinae, 382
Inguinal Regions, 324, 385
Insula Cerebri, 183
Inter-brain, 192
Interspaces, Perinatal, 393
Intestine, Large, 333
Small, 330
Intestinum Crassum, 333
Tenue, 330
Intumescentia Ganglioformis, 225
Iris, 284
Ischio-pubic Ramus, 12
Ischio-rectal Fossa, 394
Anterior Extension of, 394
Region, 394
Space 394
Ischmm, 13
Island of Reil, 183
Isthmus Cerebri, 194
of Fallopian Tube, 382
Faucium, 314
of Hind-brain, 203
Rhombenecephali, 178, 203
of Thyroid Gland, 345
Tubas Auditivae, 303
Uterinae, 382
Iter Chordae Anterius, 19, 300
Posterius, 300
a Tertio ad Quartum Ventriculum,
202
Ivory, 318
JACOB'S Membrane, 287
Jacobson's Nerve, 221, 250, 303
Organ, 278
Joint, see Articulations
Ankle, 71
Elbow, 66
Hip, 68
Rotators of the Hip- joint, 112
Knee, 69
Shoulder, 65
Wrist, 67
Joints, Motion in, 60
Structure of, 60
Jugular, Foramen, 42
Fossa, 1 8, 21
Ganglia, 226
Process, 18
Surface, 21
Vein, 165
KNEE-JOINT, 69
Kidney, 360
Kirkring's Valves, 332
Krause's End-bulbs, 177. 272
LABI A Oris, 312
Pudendi Majora, 377
Minora, 377
Labium Tympanicum, 309
Vestibulare, 309
Labyrinth, 304
Membranous, 304, 307
Osseous, 304, 305
Lacertus Fibrosus, 133
Lachrymal, see Lacrimal
Lacrimal Apparatus, 295
Bone, 29
Canaliculi, 295
Canals, 295
Carunci, 295
Fossa, 15, 36
Glands, 300
Groove, 24
Nerve, 218, 246
Papilla, 294
INDEX
413
Lacrimal Punctum, 294
Sac, 296
Lacteals, 171, 332
Lacuna Magna Urethrae, 369
Lacunae, 4
Lacus Lacrimalis, 293
Lamina Basilaris, 309
Chorio-capillaris, 283
Cinerea, 186
Cribrosa Auris, 311
Scleraj, 281
Elastica, 282
Pusca, 281
Papyracea, 26
Reticularis, 310
Spiralis, 306
Superchoroidea, 283
Terminalis, 186
Vasculosa, 283
Laminae, 5
Lancisi's Nerves, 190
Larynx, 350
Layer, Basilar (skin), 270
Ganglionic (retinal), 286
Granular (cerebellar), 209
Molecular (cerebellar), 209
(retinal), 286
Nuclear (retinal), 286
Papillary (skin), 271
Pigmentary (retinal), 287
of Rods and Cones (retinal), 286
Rust-colored (cerebellar), 208
Turner's (cerebellar), 208
Leg, 54
Lemniscus, Lateral, 199
Medial, 198
Lens, Crystalline, 288
Lieberkuhn's Crypts, 332
Ligament, 60
Ligament or Ligaments —
Acromio-clavicular, 65
Alar, 71
of Ankle-joint, 72
Annular, Anterior, 105
Posterior, 105
Anterior Common, 61
Arcuate, 107
Astragalo-navicular, 72
Atlanto-axial, 61
Atlo-axoid, 61
of the Bladder, 366
Broad of Liver, 338
of 'Uterus, 381
Burns', 390
Calcaneo-astragaloid, 72
Calcaneo-cuboid, 72
Calcaneo-navicular, 72
Capsular, see Individual Joints
Carpo-metacarpal, 68
of Carpus, 67
Check, 62, 80
Chondro-sternal, 63
Chondro-xyphoid, 63
Coccygeal, 63
Conoid, 65
Coraco-acromial, 65
Coraco-clavicular, 65
Coraco-humeral, 65
Ligaments, Coronal, 71
Coronary, 71, 327
Costo-clavicular, 65
Costo-central, 62
Costo-transverse, 63
Costo-yertebral, 62
Cotyloid, 69
Crico-arytenoid, 353
Crico-thyroid Capsular, 353
Crico-tracheal, 353
Crucial, 70
Cruciform, 62
Deltoid, 72
Dentate, 213
Dorsal, see Individual Joints
of Elbow- joint, 66
of Eye, 280
Falciform, 64, 339
of Fingers, 68
of Foot, 72
Gimbernat's. 387
Glenoid, 65
Glosso-epiglottic, 353
of Hand, 68
Key's, 390
of Hip-joint, 69
Hyo-epiglottic, 352
Ilio-femoral, 69
Ilio-lumbar, 63
Ilio-pectineal, 107
of Incus, 302
Inguinal, 387
Interarticular, 62
Interchondral, 63
Interclavicular, 65
Interosseous, see Individual Joints
Interspinous, 61
Intertransverse, 61
Intervertebral, 61
Ischio-fempral, 69
of Knee-joint, 69
of Larynx, 352
of Larynx, 352
Lateral, see Individual Joints
Lieno-renal, 348
of Liver, 338
Lockwood's, 76, 281
Lumbo-sacral, 63
of the Lung, 356
of Malleus, 302
Metacarpal, 68
Metacarpo-phalangeal, 68
Metatarsal, 73
Metatarso-phalangeal, 73
Nuchal. 6 1, 88
Occipito-atlantal, 62
Occipito-axial, 62
Occipito-odontoid, 62
of the Odontoid Process, 62
Orbicular of Radius, 66
of the Ossicles, 302
of the Ovary, 383
Palpebral, 294
Patellar, 69
Pectineo-femoral, 69
Peritoneal, 326, 327
Phreno-colic, 335
Plantar, 72
4i4
INDEX
Ligaments, Posterior Common, 61
Poupart's, 108, 387
Pterygo-mandibular, 78
Pubic, 64
Pubo-prostatic, 366
Pubo-vesical, 366
Radio-carpal, 67
Radio-ulnar, 67
Recto- vaginal, 381
Rhomboid, 65
Round of Hip- joint, 69
of Liver, 339
of Uterus, 381
Sacro-C9ccygeal, 64
Sacro-iliac, 64
Sacro-sciatic, 64
Sacro-spinous, 64
Sacro-tuberous, 64
Sacro-uterine, 381
of the Scapula, 65
of Shoulder, 65
Spiral of Cochlea, 309
or Spleen, 348
Spleno- phrenic, 348
Spheno-mandibular, 65
of Stapes, 302
Stellate, 62
Sterno-clavicular, 65
of the Sternum, 63
Stylo-hyoid, 21, 41
Stylo-mandibular, 61
Subpubic, 64
Supra-pubic, 64
Supra-spinous, 61
Suspensory of Bladder, 366
of Eye, 281
of Incus, 302
of Lens, 288, 289
of Liver, 339
of Odontoid, 62
of Ovary, 383
of Penis, 393
of Spleen, 348
Tarsal of Eye, 294
Temporo-mandibular, 60
Thyro-arytenoid, 353
Thyro-epiglottic, 353
Thyro-hyoid, 353
Tibio-fibular, 71
Transverse of Atlas, 61
Cotyloid, 69
of Knee, 71
of Scapula, 46
Trapezoid, 65
Triangular, 393
Ulno-carpal, 67
Utero-sacral, 381
Utero-vesical, 381
of the Uterus, 381
of Vertebrae, 61
of Winslow, 70
of Wrisberg, 71
Y-ligament, 69
of Zinn, 76
Ligamentum or Ligamenta —
Alaria, 71
Arcuata, 107
Calcaneo-fibulare, 72
Ligamenta, Calcaneo-tibiale, 72
Carpi Dorsale, 105
Transversum, 105
Collaterale, Fibulare, 70
Radiale, 66
Tibiale, 70
Ulnare, 66
Coronaria Hepatis, 327, 339
Cruciata Cruris, 115
Denticulatum, 213
Falciforme Hepatis, 339
Gastro-lienale, 326
Hepato-gastricum, 326
Hyo-thyreoidea, 353
Inguinale, 387
Reflexum, 387
Laciniatum, 115
Lacunare, 387
Lata Uteri, 381
Latum Pulmonis, 356
Lieno-renale, 327
Mucosum, 71
Nuchae, 61, 88
Patellae, 69
Pectinatum Iridis, 285
Peronaei Retinaculum, 115
Sacro-spinosum, 64
Sacro-tuberosum, 64
Spirale Cochleae, 309
Suspensorium Dentis, 62
Talo-fibulare, 72
Teres Femoris, 69
Hepatis, 339
Umbilicale, 365
Uteri, 381
Thyreo-epiglotticum, 353
Transversum Cruris, 115
Triangulare Hepatis, 339
Light Spot, 298
Limbus Fossae Ovalis, 119
Laminae Spiralis, 309
Line, Inter-trochanteric, 53
Popliteal, ss
Linea Aspera, 53
Ilio-pectinea, 14
Quadrati (inter-trochanteric ridge),
Lines, Schreger's, 319
Lingua, 273
Lingula Cerebelli, 203
Lips, 312
Liquor Morgagni, 289
Lithotomy, Structures Concerned, 396
Littr6's Glands, 369
Liver, 336
Structure of, 339
Lobe of the Ear, 297
Lobes and Gyri of the Brain —
Ala Lobuli Centralis, 207
Amygdala, 207
Angular, 185
Biventral, 207
Broca's, 185
Buccal, 188
Centralis, Anterior, 185
Posterior, 185
Clivus Monticuli, 207
Commissura Simplex, 207
INDEX
415
Lobes, Cresenctic, 207
Culmen Monticuli, 207
Cuneus, 186
Dentate, 191
Diclive, 207
Flocculus, 207
Folium Cacuminis, 207
Fraenulum, 207
Frontal, 185
Fusiformis, 186
Glandular, 188
Gracile, 207
Hippocampal, 186
Limbic, 183
Lingualis, 186
Lingula, 207
Lobulus Centralis, 207
Occipital, 186
Occipito-temporal, 186
Olfactory, 183
Operti, 1 86
Orbital, 185
Parietal, 185
Postcentral, 186
Postparietal, 185
Precentral, 186
Precuneus, 185
Pyramid, 207
Semilunar, 207
Slender, 207
Subcalcarine, 186
Supramarginal, 185
Temporal, 183, 186
Tonsil, 207
Tuber Valvulae, 207
Uncinate, 186
Uvula, 207
Vermis, 206, 207
Vinculum Lingulae, 207
Worm, 206, 207
Lobes of the Cerebellum, 207
of the Cerebrum, 183
of the Liver, 338
of the Prostate Gland, 370
of the Thyroid Gland, 345
Lobule of the Ear, 297
Lobules of Liver, 340
of the Lung, 359
of the Mammary Gland, 384
Lobus Caudatus, 338
Quadratus, 338
Spigelii, 338
Lockwood's Ligament, 76
Locus Caeruleus. 20 a, 212
Perforatus, 186
Loops of Henle, 362
Lower's Tubercle, 120
Lumbar Regions, 324
Lumbo-dorsal Fascia, 90
Lungs, 357
Lunula, 273
Lymphatic System, 171
Vessels, 171
Lymph Glands, 171
Haemal, 172
Space, Peri-choroidal, 283
Peri-sclerotic, 281
Spaces of Eye, 290
Lymphatics of the —
Abdomen, 174
Auricular Region, 173
Bladder, 368
Bronchi, 175, 356
Buccal Region, 173
Cardiac Region, 175
Cervical Region, 173
Head, 172
Inguinal Region, 174
Intestine, 333, 336
Larynx, 354
Liver, 341
Lower Extremity, 174
Lung, 359
Kidney, 363
Mammary Gland, 384
Mastoid Region, 173
Mediastinum, 175
Mesentery, 175
Neck, 172, 173
Pancreas, 344
Parotid Regi9n, 173
Pectoral Region, 174
Pelvis, 174
Occipital Region, 172
Spleen, 349
Submandibular Region, 173
Supra-renal Gland, 365
Testicle, 375
Thymus Gland, 347
Thyroid Gland, 346
Tongue, 275
Trachea, 356
Upper Extremity, 173
Uterus, 382
Vagina, 379
Lympho-glandulae, 171
Auriculares, 173
Bronchiales, 175, 356
Ceryicales, 173
Cubitales, 173
Linguales, 173
Mesentericae, 175
Occipitales, 172
Parotidae, 173
Submaxillares, 173
Lyra, 190
MACULA Acustica, 307
Lutea, 285
Saccularis, 308
Utricularis, 308
Malar Bone, 30
Malleolus, 55. 56
Malleus, 301
Malpighi's Bodies, 349, 361
Pyramids, 361
Malpighian Tufts, 361
Mammary Gland, 383
Mandible, 33
Manubrium of Malleus, 301
of Sternum, 8
Marrow of Bones, 4
Massa Intermedia, 193
Masses, Lateral of Ethmoid, 26
Mastoid, 3
Cells, 20
4i6
INDEX
Mastoid, Foramen, 20
Process, 20
Matrix of Nail, 273
Maxilla, 27
Meatus Acusticus Externus, 297
Interims, 311
Auditorius Externus, 20, 297
Internus, 20, 42, 311
Nasi, 3.8, 277
Urinarius, 369, 370
Meckel's Diverticulum, 331
Ganglion, 224
Media, Refracting of Eye, 287
Mediastinum Testis, 374
Thoracis, 356
Medulla Oblongata, 208
Spinalis, 213
Membrana Basilaris, 309
Crico-thyroidea, 353
Granulosa, 383
Limitans Externa, 287
Interna, 286
Nictitans, 295
Pupillaris, 285
Sacciformis, 67
Tectoria, 309
Tympani, 298
Secundaria, 300
Membrane or Membranes —
Brain, 180
Bruch's, 283
Demour's, 282
Descemet's, 282
Hyaloid, 288
Hyo-glossal, 274
Hyo-thyroid, 353
Interosseous, 67, 71
Jacob's, 287
Limiting, 286, 287 .
Meningeal, 180, 213
Mucous, 271
Nasmyth's, 319
Obturator, 12
Pituitary, 278
Reissner's, 309
Schneiderian, 278
Shrapnell's, 298
of Spinal Cord, 213
Synovial, 60
Carpal, 67
Tarsal, 72
Thyro-hyoid, 353
Thyroid, 12
Vestibular, 309
Meninges of Brain, 180
of Spinal Cord, 213
Menisci of Knee-joint, 70
Mesenteries, 327
Mesencephalon, 178, 203
Mesencephalic Root of Fifth Nerve,
Meso-colon, 327, 334
Meso-rectum, 327
Meso-sigmoid, 327
Metacarpus, 51
Metapore, 182, 211
Metatarsus, 58
Metathalamus, 193
Metencephalon, 178, 203
Meynert's Commissure, 292
Mid-brain, 178, 194
Modiolus Cochleae, 306
Moll's Glands, 293
Mons Veneris, 377
Morgagni's Hydatids, 373, 382
Lacuna, 360
Sinus, 359
Mouth, 312
Miiller's Fibres, 286
Munro's Foramen, 190
Muscle or Muscles, 73
Abdominal, 95
Abductor Digiti Quinti (hand), 106
.(foot), 116
Indicis (ist dorsal interosseous),
107
Minimi Digiti (foot), 116
Digiti (hand), 106
Pollicis, 106
Brevis, 106
Longus, 105
Accelerator Urinae, 98
Accessories ad Ilio-costalem, 91
of Acromial Region, 100
Adductor Brevis (femoris), no
Longus (femoris), no
Magnus (femoris), no
Obliquus Hallucis, 117
Ppllicis, 106
Pollicis, 106
Transyersus Hallucis, 117
Pollicis, 106
Ancpneus, 104
Anti-tragicus, 80, 297
Appendicular, 86, 87
of Arm, 100
Articularis Genu, 109
Aryteno-epiglottideus Inferior, 86
Superior, 86
Arytenoideus, 86
Attollens Auriculam, 75
Attrahens Auriculam, 75
of Auricle, 297
Auricularis Anterior, 75
Posterior, 75
Superior, 75
Axial. 87
ygos UT
of Back, 86
Azygos Uvulae, 84
Biceps, ip i
Femoris, 112
Flexor Cubiti, 101
Biventer Cervicis, 92
of the Bladder, 367
Bowman's (ciliary), 284
(Cochlear), 309
Brachialis, 101
Anticus, loi
Brachio-radialis, 104
of Buccal Region, 78
Buccinator, 78
Bulbocavernosus, 98
Caninus, 77
of Cervical Region, 80, 84
Cervicalis Ascendens, 91
Chondro-glossus, 81
Ciliary, 284
INDEX
417
Muscles, Circumflexus (tensor) Palati, 83
Coccygeus, 98
Complexus, 92
Compressor Narium Minor, 77
Nasi, 77
Sacculi Laryngis of Hilton (ary-
teno-epiglottideus inf.), 86
Urethrae (female), 99
(male), 98
Constrictor Isthmi Paucium, 84
Pharyngis In
Middle, 83
is Inferior, 83
Superior, 83
Coraco-brachialis, 101
of Cranial Region, 75
Corrugator Cutis Ani, 97
Supercilii, 75
Cremaster, 95
Crico-arytenoid, Lateral, 86
Posterior, 85
Crico-thyroid (thyreoideus), 85
Crureus, 109
Cursor Ani (latissimus dorsi), 88
Deltoid (deltpideus), 100
Depressor Ali Nasi, 77
Anguli Oris, 78
Labii Inferioris, 78
Septi Nasi, 77
Detrusor Urinse (outer muscular
coat of the bladder), 367
Diaphragm, 94
Digastric, 82
Dilator Naris Anterior, 77
Posterior, 77
Pupillae, 285
Tubae Auditivae, 303
of Dorsal Region, 86
of the Ear, 75. 79, 297
Ejaculator Seminis (bulbo-caverno-
sus), 98
U rinse (bulbo-cavernosus), 98
of the Epiglottis, 85, 354
Erector Clitoridis (ischio-caverno-
sus), 09
Penis (ischio-cavernosus), 99
SpinEB, 90
of the Eustachian Tube, 303
of Expression, 77, 79
Extensor Brevis Digitorum, 115
Pollicis, 1 05
Carpi Radialis Brevoir, 104
Longior, 104
Ulnaris, 104
Coccygis, 93
Communis Digitorum, 104
Digiti Quinti Proprius, 104
Hallucis Longus, 113
Indicis, 105
Longus Digitorum, 113
Hallucis, 113
Pollicis, ip$
Minimi Digiti, 104
Ossis Metacarpi Pollicis, 105
Extensor, Primi Internodii Pollicis,
105
Proprius Hallucis, 113
Secundi Internodii Pollicis, 105
External Oblioue (abdomen), 95
Muscles of Eyeball, 76, 289
of Eyelid, 75, 294
of the Face, 77, 79
of the Femoral Region, 108, no, 112
of the Fibular Region, 115
Flexor Accessorius, 116
Brevis Digitorum, 116
Hallucis, 117
Minimi Digiti (foot), 117
(hand), 106
Pollicis, 106
Carpi Radialis, 102
Ulnaris, 103
Digiti Quinti Brevis (foot), 117
(hand), 106
Digitorum Brevis, 106
Hallucis Brevis, 117
Longus Digitorum, 114
Hallucis, 114
Pollicis, 103
Ossis Metacarpi Pollicis (oppo-
nens), 106
Pollicis Brevis, 106
Longus, 103
Profundus Digitorum, 103
Sublimis Digitorum, 103
of the Forearm, 102
of the Foot, 115
Frontalis, 75
Gastrocnemius, 113
Gamellus Inferior, in
Superior, in
Genio-glossus, 82
Genio-hyo-glossus, 82
Genio-hyoid, 82
Glosso-palatinus, 84
of the Gluteal Region, no
Glutaeus or Gluteus Maximus, no
Medius, no
Minimus, ill
Gracilis, 109
Hamstring, 112
of the Hand, 106
of the Head, 75
Helicis Major, 79, 297
Minor, 80, 297
Hilton's (aryteno-epiglottideus in-
ferior), 86
of the Hip, 1 10
Hip Rotators, 112
Homer's (tensor tarsi), 75
of Humeral Region, 101
Hyo-glossus, 82
Hyppthenar, 106
of Iliac Region, 107, no
Iliacus, 108
Ilio-capsularis (outer fibres of
iliacus), 108
Ilio-coccygeus (posterior fibres of
levator ani), 98
Ilio-costales, 91
Lumborum, 91
Infra-cost ales, 94
Infra-hyoid Region, 81
Infraspinatus, 101
Intercostal, External, 93
Internal, 93
Internal Oblique (abdomen), 95
4*8
INDEX
Muscles, Interossei of foot, 117
Inter-spinales, 93
Inter-transversaTes, 92
Iritertransversarii, 93
Involuntary, 74
Ischio-cavernosus, 98, 99
of Ischio-rectal Region, 97, 395
Kerato-cricoideus, 85
Labial Region, 77
of Larynx, 85, 354
Latissimus Dorsi, 88
Laxator Tympani, 80
of the Leg, 112
Levator Anguli Oris, 78
Scapulae, 88
Ani, 98
Glandulae Thyroideae, 346
Labii Superioris, 77
Alasque Nasi, 77
Menti, 78
Palati, 83
Palpebrae Superioris, 76
Prostatae (pre-anal fibres of
levator am), 98
Scapulae, 88
Urethrae (pre-anal fibres of
levator ani), 98
Veli Palatini, 83
Levatores Costarum, 94
Lingualis, 83
Lingual, Longitudinal, 83
Transverse, 83
Vertical, 83
of Lingual Region, 82
Longitudinalis Linguae Inferior, 83
Superior, 83
Longissimus Capitis, 91
Cervicis, 91
Dorsi, 91
Longus Capitis, 84
Colli, 84
of Lower Extremity, 107
Lumbricales of foot, 116
of hand, 107
Mandibular Region, 78
Masseter, 79
of Mastication, 79
of Maxillary Region, 77
Mentalis, 78
Multifidus, 92
Spinae, 92
Mylo-hyoid, 82
Nasalis, 77
of Nasal Region, 77
Naso-labialis (upper medial fibres
of orbiculans oris), 78
of Neck, 80
Obliquus Abdominis Externus, 95
Internus, 95
Auriculae, 80, 297
Capitis Inferior, 93
Superior, 93
Oculi Inferior, 77
Obliquus Oculi, Superior, 76
Obturator Externus, 112
Internus, 112
Occipitals, 75
Occipito-frontalis, 75
Muscles, Omo-hyoid, 81
Opponens Digiti Quinti, 107
Minimi Digiti, 107
Ppllicis, 106
Orbicularis Oculi, 75
Oris, 78
Palpebrarum, 75
of Orbital Region, 76, 289
of Palatal Region, 83, 313
Palato-glossus, 8j
Palato-pharyngeus, 84
of Palmar Region, 106
Palmaris Brevis, 106
Longus, 102
of Palpebral Region, 75
Fectineus, no
of Pectoral Region, 99
Pectoralis Major, 99
Minor, 99
of Pelvic Outlet, 97
Perforans, 103
Perforatus, 103
of Perinaeum, female, 99, 396
Male, 98, 393
of Peroneal Region, 115
Peroneus (peronasus) Brevis, 115
Longus, 115
Tertius, 113
of Pharyngeal Region, 83, 322
Pharyngo-glossus (superior con-
strictor), 83
Pharyngo-palatinus, 84
of Pinna, 79
of Plantar Region, 116
Plantaris, 114
Platysma-myoides, 80
Popliteus, 114
Prevertebral of Head and Neck, 84
Procerus, 77
Pronator Quadratus, 103
Radii Teres, 102
Teres, 102
Psoas Magnus, 107
Major, 107
Minor, 108
Parvus, 108
of Pterygo-mandibular Region, 79
Pterygoid, External, 79
Internal, 79
Pubo-coccygeus (medial fibres of
levator ani), 98
Pyrarnidalis, 97
Nasi, 77
Pyraformis, in
Quadratus FenKms, 112
Labii Inferioris, 78
Superioris, 78
Lumborum, 97
Menti, 78
Plantae, 116
Quadriceps Extensor, 108
Femons, 108
Radial Region, 102
Recti Oculi, 76
Recto-urethralis (pre-anal fibres
of levator ani), 98
Recto-uterinus (sacro-uterine liga-
ment), 381
INDEX
419
Muscles, Rectus Abdominis, 96
Capitis Anticus Major, 84
Minor, 84
Lateralis, 84, 93
Posticus Major, 93
Minor, 93
Femoris, 109
Oculi Externus, 76
Inferioris, 76
Internus, 76
Lateralis, 76
Medialis, 76
Superioris, 76
Retrahens Auriculam, 75
Rhomboideus Major, 89
Minor, 88
Risorius, 79
Rotatores, 92
Spinse, 92
Rotators of the Hip, no
Sacro-lumbalis, 91
Sacro-spinalis, 90
Salpingo-pharyngeus, 84
Santorini's (risorius), 79
Sartorius, 108
Scalenus Anticus (anterior), 85
Medius, 85
Posticus (posterior), 85
of the Scalp, 75
of Scapular Region, 100
Semi-membranosus, 112
Semi-spinalis Capitis, 92
Cervicis, 92
Colli, 92
Dorsi, 92
Serratus, Anterior, 100
Magnus, 100
Posticus (posterior) Inferior, 90
Superior, 89
of the Shoulder, 100
Skeletal (voluntary), 73, 74
Sphincter Ani Externus, 97
Internus, 97
Tertius, 97
Pupillae, 285
Vaginae, 99
Vesicae, 367
Spinalis Cervicis, 92
Colli, 92
Dorsi, 92
Splenius Capitis, 90
Cervicis, 90
Colli, 90
Stapedius, 80, 302
Striated Muscle, 73, 74
Striped Muscle, 73, 74
Structure of Muscle, 73
Stylo-glossus, 82
Stylo-hyoid, 82
Stylo-pharyngeus 83
Sub-anconeuc, 102
Subclavius, 100
Subcrureus, 109
of Suboccipital Region, 93
Subscapularis, 100
Supinator, 105
Brevis, 105
Longus, 104
Muscles of Supra-hyoid Region, 82
Supraspinatus, 101
Temporal, 79
of Temporo-mandibular Region, 79
Tensor Fasciae Femoris, 108
Latae, 108
Palati, 83
Tarsi, 75
Tympani, 80, 302
Vaginae Femoris, io3
Veli Palatini, 83
Teres Major, 101
Minor, 101
Thenar, 106
of Thigh, 108
of Thorax, 93, 99
Thyro-(thyreo) Arytenoideus, 86
Thyro-(thyreo) Epiglottideus, 86
Thyro-(thyreo) Hyoid, 81
Tibialis Anticus (anterior), 112
Posticus (posterior), 114
of Tibio-fibular Region, 112
Todd's (cochlear), 309
of the Tongue, Extrinsic, 82, 274
Intrinsic, 83, 275
Trachelo-Mastoid, 91
Tragicus, 80, 297
Transversalis Abdominis, 96
Cervicis, 91
Colli, 91
Transversus Auriculae, 80, 297
Linguae, 83
Pennaei Profundus, 98, 99
Superficialis, 98, 99
Trapezitts, 88
Triangularis Menti, 78
Sterni, 94
Triceps, 102
Extensor Cubitis, 102
Triticeo-glossus, 86
of the Trunk, 86
Turner's (Kerato-cricoideus), 85
of Tympanum, 80, 302
of Ulnar Region, 102
Unstriated Muscle, 73, 74
Unstriped Muscle, 73. 74
of Upper Extremity, 99
Urethral, 369
Uvulae, 84
Vastus Externus, 109
Intermedius, 109
Internus, 109
Lateralis, 109
Medialis, 109
Vertical is Linguae, 83
Voluntary Muscle, 73, 74
Zypomaticus, 78
Major, 78
Minor, 78
Muscular Fibre, 73
Musculi Papillares, 120, 122
Myencephalon, 177. 208
Myelology,
NAILS, 272
Nares, 276
Nasal Bones, 27
Conchae, 26, 32
Fossa, 277
420
INDEX
Nasal Meatus, 26, 277
Septum, 276
Nasmyth's Membrane, 319
Naso-labial Band, 78
Nasopharynx, 321
Nates, 202
Navel, 298
Navicular Bone, 57
Neck of the Bladder, 366
of the Femur, 52
of the Humerus, 47
Surgical Triangles of, 128
of the Uterus, 398
Nerve or Nerves —
Abducent, 219, 252
Accessorius, 222, 250
Acustic, 220, 310
Alveolar, 219, 246
Anastomoticus Tibialis, 235, 236
of Ankle-joint, 235
of the Arm, 229
Arnold's, 221, 250
Auditory, 220, 310
of Auditory Canal, 219, 246
of Auricle, 298
Auricular, Anterior, 219, 246
Great, 227, 254
from Pneumogastric, 221, 250
Posterior, 220, 248
Auricularis Magnus, 227
Axillaris, 229
Bell's, 229
of Bladder, 368
of Bronchi, 356
Buccal, of Facial, 220, 248
Long, 219
of ME
[andibular, 219, 246
Buccinator, 219, 246
Calcaneal, Lateral, 235, 267
Medial, 235, 267
Calcaneo-plantar, 235, 267
Canalis Pterygoidei, 226
Cardiac, 119
Cervical, 222, 237, 250, 268
Inferipr, 222
Superior, 222, 237, 268
Thoracic, 222, 250
Carotico-tympanic, 237
Carotid, 221
Cavernus, 242
Cells, 176
Cerebral, 216
Cervical, 220, 227
Cervico-facial, 220, 248
Chorda Tympani, 220, 248, 276
Ciliary, Long, 218, 246
Short, 224
Circumflex, 229, 260
Clunium Inferioris Medialis, 234
Coccygeal, 233, 262
Cochlear, 221, 252, 311
Communicantes, Gray Rami, 227
Fibular, 236
Hypoglossi, 228, 254 *
Peronei, 236, 267
Tibial, 235, 267
'White Rami, 227, 238
Cranial, 216
Nerves, Crural, Anterior, 233, 264
Genito-, 232, 264
Cutaneous, Abdominal, 231
Antibrachii Medialis, 229
Posterior, 229
Brachii Medialis, 229
Posterior, 230
C9lli, 227
Digitales Plantares, 235
Volares, 229
Dorsal, 230
Antibrachial, 229
Femoral, 234
External Femoral, 232, 264
Internal, 229, 256
Femoral, 233
Lateral Brachial, 229
Femoral, 232
Lesser Internal. 229, 256
Medial Antibrachial, 229
Brachial, 229
Femoral, 233, 264
Palmar, 229
Perforating 234, 266
Plantar, Lateral, 235
Medial, 236
Posterior Antibrachial, 229
Femoral, 234
Surae Lateralis, 236
Medialis, 235
Dental, Anterior Superior, 219, 246
Inferior, 219, 246
Middle Superior, 219, 246
Posterior Superior, 219, 246
Descendens Hypoglossi, 222, 252
Digastric of Facial, 220, 248
of Mylo-hyoid, 219, 246
Digital (foot), 235
(hand), 229
Digitales Plantares, 235
Volares, 229
Dorsal of Clitoris, 234, 266
of Penis, 234, 266
of the Ear, see Individual Portions
Eighth Cranial, 220, 252, 311
of Elbow-joint, 230
Eleventh Cranial, 222, 250
of Equilibration (vestibular), 221,
252, 319
Endings, 177
of Eustachian Tube, 304
of Eyeball, 218, 219, 289
of Eyelids, 218, 219, 289
Eye-muscles, 218, 219, 289
Facial, 220, 248
Femoral, 233
Fibres, 177
Fifth Cranial, 218, 2^6
First Cranial, 216, 244
Fourth Cranial, 217, 244
Frontal, 218, 246
Gastric, 222
Genital, 232, 264
Genito-crural, 232, 264
Genito-femoral, 232, 264
Glosso-palatine, 220, 248, 310
Glosso-pharyngeal, 221, 250
Gluteal, Inferior, 234, 266
INDEX
421
Nerves, Gluteal, Superior, 234, 266
Gustatory, 219, 246
Haemorrhoidal, 234, 266
of Heart, 119
Hepatic, 340
of Hip-joint, 234
Hypo-glossal, 222, 252
Ilio-hypqgastric, 232, 264
Ilio-inguinal, 232, 264
Incisive, 219, 246
Infra-orbital, 218, 220, 246
Infra-trochlear, 218, 246
Intercostal, Abdominal, 231, 261
Thoracic, 231, 261
Intercosto-brachial, 231
Intercosto-humeral, 231
Intermedius (glosso-palatine), 220,
248, 310
Interosseous. Anterior from Median,
229, 258
from Anterior Tibial, 236
Antibrachii Dorsalis, 230
Volaris, 229
Posterior from Musculo-spiral,
230, 258
of the Intestines, 333, 336
of the Iris, 28$
Ischiadicus, 234
Jacobson's, 221, 250, 303
of the Kidney, 363
of the Knee-joint, 235
Labial, 219, 246
Lacrimal, 218, 246
Lancisi's, 190
Laryngeal, External, 221, 250
Inferior, 222, 250
Internal, 221, 250
Recurrent, 222, 250
Superior, 221, 250
of the Larynx, 354
Lingual from Mandibular, 219, 246,
from Glosso-pharyngeal, 221, 250
of the Liver, 340
Lumbar, 232, 262
Malar, 219, 220
of the Mammary Gland, 384
Mandibular, 219, 246
Masseteric, 219, 246
Masticator, 201, 219, 246
Mastoid, 227
Maxillary, 218, 246
Median, 229, 258
of Membrana Tympani, 299
Meningeal, from sth, 219, 246
from loth, 221, 250
from I2th, 222, 250
of the Cord, 227
Recurrent, 227
Mental, 219
Motor-oculi, 217, 244
Musculo-cutaneous of Arm, 229,
258
of leg, 236, 267
Musculo-spiral, 230, 255
Mylo-hyoid, 219, 246
Nasal, 218, 219, 246
Posterior Inferior, 224
Superior. 224
Nerves, Nasal, Superior, 224
Naso-ciliary, 218
Naso-palatine, 224
Ninth Cranial, 221, 250
of the Nose, 279
Obturator, 232, 244, 264
Accessory, 232, 264
Occipital, Great, 227, 254
Small, 227, 254
Occipitalis Magnus, 227
Minimus, 227
Oculo-motor, 217, 244
Oesophageal, 222, 250
Olfactory, 216, 244
Ophthalmic, 218, 246
Optic, 217, 244, 291
Orbital, 219, 224, 246
of Orientation (vestibular) , 221,
252, 311
of the Ovary, 383
Palatine, Anterior, 224
External, 224
Large, 224
Medial, 224
Middle, 224
Posterior, 224
Small, 224
Palmar, 229, 230, 258, 260
Palpebral, 219, 246
of the Parotid, 219, 246
Pars Intermedia (glosso-palatine),
220, 248, 310
Patheticus, 217
Path, Optic-acustic Reflex, 199,
200
of the Penis, 372
Peronaeus Profundus, 236
Superficials, 236
Petrosal, Deep, 237
Great Superficial, 225
Small Superficial, 225
Pharyngeal, 224
from Ninth Cranial, 221, 250
from Tenth Cranial, 221, 250
Phrenic, 228, 254
Plantar, 235, 267
Plexuses, see Plexus
Pneumogastric, 221, 250
Popliteal, External, 235, 267
Internal, 235, 267
Portio Dura, 220
Mollis, 220
of the Prostate Gland, 371
Pterygoid, External, 219, 246
Internal, 219. 246
Pterygo-palatine, 224
Pudenda! Inferior, 234
Long, 234
Pudendus, 234
Pudic, 234, 266
Pulmonary, 222, 250
Radial, 230, 256
Radialis, 230, 256
Rami Communicantes, Gray, 227,
238
White, 227. 238
Respiratory, of Bell, 229
External, 229
422
INDEX
Nerves, Respiratory, Internal, 228
Sacral, 233, 262
Saphenous, External, 235, 267
Internal, 233, 264
Long, 233, 264
Short, 235, 266
Sciatic, Great, 234, 266
Small, 234, 266
Scrotal, 232
Second Cranial, 217, 244, 291
Seventh Cranial, 220, 248
of Shoulder-joint, 65
Sixth Cranial, 219, 252
of the Spermatic Cord, 377
Spheno-palatine, 219, 246
Spinal, 216, 226, 254
Accessory, 222, 250
Splanchnic, Great, 227, 238, 268
Small, 227
of the Spleen, 241, 349
of the Stomach, 330
Stylo-hyoid, 220, 248
Stylo-pharyngeal, 221, 250
Suboccipital, 227, 254
Subscapular, 229, 260
Superficialis Colli, 227, 254
Supra-aero mial, 228
Supra-clavicular, 228
Supra-orbital, 218, 2^6
of the Supra-renal Gland, 365
Suprascapular, 229
Suprasternal, 228
Supratrochlear, 218, 246
Sural, 235, 236
Sympathetic, 236, 268
of Taste, 275, 276
Temporal, Deep, 219, 246
Superficial, 220, 248
Superior, 219, 246
Temporo-facial, 220, 248
Temporo-malar, 219
Tensoris Tympani, 225
Veli Palatim, 225
Tenth Cranial, 221, 250
Terminations of, 177
of Testicle, 375
Third Cranial, 217, 244
Thoracic, 231
Anterior, 229, 258, 260
Intercostals, 261
Long, 229, 256
Posterior, 229, 256
Thoraco-dorsalis, 229
of Thymus Gland, 347
Thyro-hyoid, 222, 252
of Thyroid Gland, 346
Tibial, Anterior, 236, 267
Posterior, 235, 267
Tibialis, 235
of the Tongue, 275, 276
Tonsillar, 221, 250, 315
of Trachea, 356
Trifacial, 218, 246
Trigeminal, 218, 246
Trochlear, 217, 244
Trancus Lumbo-sacralis, 233
Twelfth Cranial, 222, 252
Tympanic, 220, 248, 303
Nerves of Tympanic Membrane, 299
of Tympanum, 303
Ulnar, 229, 256, 260
of the Ureters, 364
of the Uterus, 382
of the Vagina, 380
Vagus, 221, 250
Vaso-motor, 122
Vedian, 226
of the Vesiculse Seminales, 377
of the Vulva, 379
Wrisberg's, 229
of Wrist-joint, 230
Zygomatic, 219
Zygomatico-facial, 219
Zygomatico-temporal, 219
Nervous System, 175, 242
Tables and Plates, 242
Neurilemma, 177
Neuroglia, 176, 214
Neurology, i
Neurones, 176
Nipple, 384
Nodule,
207
Noduli Lymphatici Agregati, 333
Lienalis, 349
Valvarum Semilunarum, 120
Nose, 276
Vestibule of, 176
Notch, Cerebellar, 206
Cotyloid, 12
Ethmoidal, 16
Frontal, 15
Great Sciatic, 13
Interclavicular, 8
Intercondylar, 54
Lesser Sciatic, 13
Nasal, 15
Popliteal, 53
of Rivini, 298
Sacro-iliac, 13
Sacro-sciatic, 13
Sigmoid, 34
Supraorbital, 14, 37
Suprascapular, 46
Thyroid, 350
Ulnar, 50
Nuchal Crest, 17
Ligament, 61, 88
Lines, 17
Nuck's Canal, 381
Nucleus or Nuclei, Abducent, 204
Amygdalae, 179
Anterior, 193
Auditory, 204
Caudatus, 191
Cerebellar, 208
Cuneatus, 198
Dentate, 208
Dorsal, 210, 216
Emboliformis, 208
Facial, 204
Fastigii, 208
Fourth Ventricle, 212
Globosus, 208
'Gracilis, 198
Habenulse, 194
Hypo-thalamicus, 203
INDEX
423
Nucleus, Lenticular, 192
Lentiformis, 192
Lentis, of Crystalline Lens, 288
Mesencephalic of Masticator, 202
Olivary, Accessory, 209
Inferior, 209
Superior, 204
Pontis, 204
Red, 197
Roof, 208
Stilling's, 208
Tegmenti Ruber, 197
Trigeminal, 204
Nuhn's Glands, 274
Nymphae, 377
OBEX, 212
Occipital Bone, 17
Odontoblasts, 319
Odontoid, 3
Process, 7
(Esophagus, 322
Olive, 209
Omenta, 326
Omentum, Gastro-colic, 326
Gastro-hepatic, 326
Gastro-splenic, 326
Great, 326
Lesser, 326
Opening, Saphenous, 108, 389
Optic Thalamus, 193
Ora Serrata, 285
Orbiculus Ciliaris, 283
Orbit, 35
Organ or Organa —
Accessoria Oculi, 293
Auditus, 296
of Corti, 309
of Digestion, 312
of Equilibration, 309
of Generation, Female, 377
Male, 370
of Hearing, 296
of Jacobson, 278
of Orientation, 309
of Rosenmuller, 383
of Sight, 280
of Smell, 276
of Special Sense, 270
Spirale, 309
of Taste, 273
of Touch, 272
Urinary, 360
of Voice and Respiration, 350
Vomero-nasale, 278
Orientation, 309
Orificium Uteri, 380
Os or Ossa, see Bones
Ossicula Auditus, 301
Ossification, 4
Osteology, i
Ostium Arteriosum, 121
Pulmonis, 120
Venosum Ventriculi Sinistri, 121
Ptoconia, 307
Otoliths, 307
Ovaries, 382
Ovicapsule, 383
Oviducts, 382
PACCHIONIAN Bodies, 181, 182
Paccinian Corpuscles, 177, 272
Palate, 313
Bone, 31
Pampiniform Plexus, 375, 383
Pancreas, 3*13
Lesser, 344
Panniculus Adiposus, 74
Carnosus, 74
Papilla, Lacrimal, 294
Optic, 286
Spiralis, 309
Papillae Circumvallate, 274
Filiformes, 274
of Kidney, 361
of Mammae, 384
of Skin, 271
of Tongue, 274
Vallatae, 274
Paraganglia, 345
Parathyroid Glands, 346
Parietal Bone, 16
Parotid Gland, 315
Parovarium, 383
Pars Ciliaris Retinae, 285
Flaccida Membranae Tympani, 298
Intermedia, 220, 276
Iridica Retinae, 285
Patella, 54
Path, Optic-acustic Reflex, 199, 200
Pecten Ossis Pubis, 14
Pedicles, 5
Peduncles of Cerebellum, Inferior,2O7, 209
Middle, 204, 207
Superior, 201, 207
of Cerebrum, 195
Pelvis, 9
Cavity of, 391
Fasciae of, 391
of the Kidney, 363
Penis, 371
Pericardium, n8
Pericementum, 319
Perilymph, 304
Perinaeal, Body, 395
Fossae, 393
Interspaces, 393
Perinaeum, Proper, 391
Female, 395
Male, 392
Perineurium, 177
Periosteum, 4
Peritoneum, 325
Peroneal Bone, 55
Peroneus, 55
Pes Accessorius, 191
Anserinus, 220
Hippocampi, 191
Petiolus Epiglottidis, 352
Petit's Canal, 288, 289
Petro-mastoid Bone, 19
Peyer's Glands, 333
Phaerochrome System, 344
Phalanges, 52, 58
Pharyngeal Cushion, 321
424
INDEX
Pharynx, 320
Pia Mater, 182, 213
Pillars of the Fauces, 314
of the Abdominal Ring, 386
Pjlli, 273
Pineal Gland, 194
Pinna of the Ear, 297
Pituitary Body, 186
Plate, Cribriform, 26
Orbital of Ethmoid, 26
of Frontal, 15
Perpendicular, 26
Tarsal, 294
Pleurae, 356
Plexus, Aortic, 2JT, 268
Brachial, 228, 256
Tabulated, 230
Cardiac, 239
' Cartoid, 237, 268
Cavernous, 237, 268
of the Clitoris, 242
Cervical, 227
Choroid, 190
Cceliac, 240
Colic, Left, 241
Coronary, 239, 241
Cystic, 241
Diaphragmatic, 240
Epigastric, 240
Gastric, Inferior, 241
Superior, 241, 250
Gastro-duodenal, 241
Gastro-epiploic, 241
Gullae (oesqphageal) , 323
Haemorrhoidal, Inferior, 242
Superior, 241
Hepatic, 241, 300
Hypogastric, 241, 268
Interlobular, 342
Lienal, 241, 349
Lumbalis, 232
Lumbar, 232, 262
Mesenteric, Inferior, 241
Superior, 241
(Esophageal, 222, 250, 323
Olfactory, 279
Ovarian, 2^10, 241
Palatine, 315
Pampiniform, 375, 383,
Pelvic, 2di, 268
Pharyngeal, 237, 268, 315, 322
Phrenic, 240
Prostatic, 242
Pudendal, 234
Pulm9nary, 239, 268, 358
Pyloric, 2A I
Renal, 2^0, 263
Sacral, 233, 262
Sigmoid, 241
Solar, 240
Spermatic, 2di
Spinosus, 219
Splenic, 241, 349
Supra-renal, 240
Tympanic, 303
Uterine, 2J2
Vaginal, 242, 380
Vesical, 242
Plexuses of the Sympathetic, 239, 268
Plica or Plicae —
Alares, 70
Arytaeno-epiglotticae, 352
Glosso-epiglotticae, 353
Lacrimalis, 296
Palmatse, 380
Recto-uterinae, 381
Semilunaris, 295, 314
Syriovialis Patellaris, 71
Transyersales Recti, 335
Ventriculares, 353
Vocales, 353
Point, Central Tendinous of Perinaeum,
394
Pomum Adami, 350
Pons Hepatis, 338
Tarini, 188
Varolii, 203
Porta Hepatis, 338
Portal System, 170
Porus Opticus, 286
Pouch, Douglas, 327
Laryngeal, 354
Peritoneal, 327
Recto-vaginal, 327, 366
Recto-vesical, 327, 366
Utero-vesical, 327, 366
Umbilical, 367
Poupart's Ligament, 108, 387
Praeputium, 372
Precuneus, 185
Prepuce of the clitoris, 377
of the Penis, 372
Process, Acromion, 46
Alveolar, 29
Angular, 15
Articular, 5
Auditory, 25
Basilar, 18
Clinoid, 22, 24
Condylar, 34
Coracoid, 46
Coronoid, 34, 49
Ethmoidal, 22
Falciform, 390
Frontal, 28
Fronto-sphenoidal, 30
Hamular, 25, 29
Jugular, 1 8
Lacrimal, 32
Malar, 28
Mastoid, 20
Maxillary, 32
Mental (mentum; chin), 33
Nasal, 28
Odontoid, 7
Olecranon, 48
Olivary, 22
Orbital, 30, 32
Palatine, 29
Pterygoid, 25
Pyramidal, 32
Sphenoidal, 32
Spinous, 6
Styloid, 21, 49, 50, 55
Transverse, 5
Turbinal, 26
INDEX
425
Process, Unciform, 26
Uncinate, 26
Vaginal, 21
Vermiform, 206, 334
Zygapophyseal, 5
Zygomatic, 19, 28
Processes, Ciliary, 284
Clinoid, 23
of Ingrassias, 24
Processus, Anterior, 301
Cochleariformis, 21, 301
Gracilis, 301
Lateralis, 301
Prominence, Laryngeal, 350
Tuhal, 321
Promontory, of Cochlea, 300
of the Facial Canal, 300
of the Sacrum, n
of the Tympanum, 300
Prosencephalon, 178
Prostate Gland, 370
Protuberance, Occipital, 17, 1 8
Psalterium, 190
Pterygoid, 3, 25
Pubes, 14
Pudendum Muliebre, 377
Pulmones, 357
Pulpa Dentis, 318
Lienis, 349
Pulvinar, 193
Punctum Lacrimale, 294
Pupil or Pupilla, 285
Purkinje's Cells, 176, 208
Pylorus, 329
Pyramid of the Cerebellum, 207
of the Medulla, 209
Posterior, 210
of the Thyroid Gland, 345
of the Tympanum, 301
Pyramids of Ferrein, 362
of Malpighi, 362
of Wistar (sphenoidal turbinals), 24
QUADRATE Lobe, 338
Lobule (cuneus), 186
Quadratus Femoris, 112
Labii, 78
Lumborum, 97
Menti, 78
Suadriceps Femoris, 108
uadrigeminal Bodies, 202
RADIUS, 49
Rami, Communicantes, 227, 238
Ramus, Ischio-pubic, 12
mandibular, 34
Raph6 of Medulla, 211
of the Perinaeum, 392
of the Tongue, 274
Receptaculum Chyli, 172
Recess or Recessus —
Atic, 300
Cochlearis, 305
Duodeno-jejunalis, 328
Ellipticus, 305
Epitympanic, 300
Ileo-caecalis, 328
Incudis, 300
Recess, Naso-palatine, 278
Sphaericus, 305
Spheno-ethmoidal, 277
Rectum, 335
Region or Regions, Abdominal, 95, 323
of the Arm, 100
Buccal, 78
Cervical, 80, 84
Cranial, 75
Dorsal, 86
of the Ear, 86
Epigastric, 324
of the Forearm, 102
Gastric, 324
Gluteal, no
of the Hand, 105
Hyoid, 8 1
Hypo-chondriac, 324
Hypo-gastric, 324
Hypo-thalamic, 202
Iliac, 324
Inguinal, 324, 385
Ischio-rectal, 97
Laryngeal, 86, 88
Lingual, 82
Lumbar, 324
Mandibular, 78
Maxillary, 77
Nasal, 77
Orbital, 76
Palatal, 183
Palmar, 105
Palpebral, 75
Pelvic, 97
Perineal, 98, 99
Pharyngeal, 83
Plantar, 116
Pre vertebral, 84
Pterygoid, 79
of Shoulder, 100
Suboccipital, 88, 93
Temporo-mandibular, 79
Thoracic, 93, 99
of Thigh, 112
Tympanic. 80
Umbilical, 324
Vertebral, 84, 85
Reil, Island of, 183
Renes, 360
R6te. Carpi, 135
Mucosum, 270
Testis, 374
Rcticular Formation, 211
Retina, 285, 286
Rhombencephalon, 203
Ribes, Ganglion of, 236, 268
Ribs (costae), 8
Ridge, of Aquseductus Fallopii, 300
Articular of Temporal. 19
Condylar of Humerus, 48
Crucial, 18
Gluteal, 13
Infra-temporal, 24
Inter-trocnanteric, 53
Mylo-hyoid, 34
Nuchal, 17
Pterygoid, 24
Suprameatal, 19
426
INDEX
Ridge, Temporal, 16
Rima Glottidis, 353
Palpebrarum, 293
Ring, Abdominal, Deep, 385
External, 386
Internal, 385
Superficial, 386
Crural, 389
Femoral, 389
Inguinalis Abdominalis, 385
Subcutaneous, 386
Rivinius, Duct of, 316
Notch of, 298
Rods and Cones, 287
of Corti, 310
Rolando, Fasciculus of, 209
Fissure of, 184
Root, Descending or Mesencephalic of
the Trigeminal Nerve, 201
Rosenmiiller's Fossa, 322
Gland, 295
Organ, 383
Rostrum, 3
of the Sphenoid, 24
Rugae Vaginales, 379
SAC of Hilton, 354
Lacrimal, 296
Peritoneal, 325
Saccule, 304
Sacculus Laryngis, 354
Sacro-sciatic Foramen, 64
N9tch, 13
Santorini's Cartilages, 352
Muscle (risorius), 79
Saphenous Opening, 108, 389
Sapolini, on the Chorda Tympani, 276
Scala Media, 309
Tympani, 307
Vestibuli, 307
Scapha Auriculae, 297
Scaphoid Bone, 51, 57
Scapula, 45
Scarf-skin, 270
Scarpa's Fascia, 108, 385
Foramen, 29
Ganglion, 311
Triangle, 142
Schachowa's Tubes, 362
Schreger's Lines, 319
Schindylesis, 59
Schlemm's Canal, 282
Schultze's Olfactory Cells, 278
Schwann, Substance of, 177
Sclerotic, 281
Scrotum, 373
Sella Turcica, 22
Sense, Special, 270
Septum Canalis Musculo-tubarii, 301
Crurale, 389
Femorale, 389
Lucidum, 190
Narium, 276
Nasi, 276
Pectiniforme, 371
Pellucidum, 190
Transversum, 309
Tubae, 21
Sheath, Crural, 390
Femoral, 390
Shin-bone, 54
Shoulder, 44, 65
Shoulder-blade, 45
Shrapnell's Membrane, 298
Sight, Organ of, 280
Sigmoid Flexure, 334
Sinus, Coronary, 171
Maxillaris, 27
of Morgagni, 354
Pocularis, 368
Prostatic, 368
Renis, 361
Tonsillaris, 314
Venosus, 119, 282
Sinuses, of the Dura Mater, 164
Frontal, 15
Meningeal, 164
Sphenoidal, 23
of Valsalva, 120
Venous, 163
Skin, 270
Appendages of, 272
Skull, Base of, 41
Fossse of, 41, 42
Slit, Nasal (ethmoidal fissure), 38, 41
Smell, Organ of, 276
Socia Parotid is, 316
Space, Haversian, 4
Inter-peduncular, 189
Ischio-rectal, 394
Perforated, 186, 188, 193
Perinaeal, 393
Popliteal, 54
Subarachnoid, 181
Subdural, 181
Spaces of the Eyeball, 290
Fontana's, 282
Spatia Anguli Iridis, 282
Zonularia, 288, 289
Spermatic Cord, 376
Sphenoid Bone, 22
Sphincter Pupillae, 285
Vaginae, 99
Vesicae, 367
Spinal Cord, 213
Spine, Alar, 24
Ethmoidal, 22
Frontal, 15
of the Ilium, 13
of the Ischium, 13
Mandibular, 34
Nasal, 15, 29, 31
Pharyngeal, 18
of the Pubis, 14
of the Scapula, 45
of the Sphenoid, 22
of Spix (mandibular), 34
of the Tibia, 54
Spinous, 3
Splanchnology, i
Spleen, 348
Spot, Blind, 286
Yellow, 285
Squamous, 3
Bone, 19
Stapes, 301
INDEX
427
Stenson's Duct, 316
Foramen, 29
Sternum, 8
Selling's Canal, 288
Roof Nucleus, 208
Stomach, 328
Stratum Cinereum, 202
Corneum, 270
Germinativum, 270
Granulosum, 270
Griseum Centrale, 197
Colliculi Superioris, 202
Intermedium, 197
Lemnici, 202
Lucidum, 270
Malpighii, 270
Opticum, 202, 286
Zonale, 202
Stria Terminalis, 190
Striae Acusticae, 212
Longitudinales, 190
Medullares, 212
Obliquae, 212
Stripe, Malleolar, 298
Styloid, 3
Process, 21
Submaxillary, now called Submandibu-
lar—
Substantia Adamantina, 319
Alba, see White Matter, 177
Eburnea, 319
Gelatinosa (Rolandi), 204, 209
Grisea, see Gray Matter, 176
Ossea, 319
Perforata, 186, 188, 193
Sulci, 183, see also Grooves and Fissures
Sulcus Cerebri Centralis, 184
Chiasmatis, 22
Longitudinalis Medianus, 212
Medianus Linguae, 274
Nervi Oculo-motorii, 22
Radialis, 47
Sagittalis, 15
Spiralis Internus, 309
Tympanicus, 298
Supercilia, 293
Sustentaculum Tali, 57
Sutura, 59
Suture or Sutures —
Coronal, 16, 40
Cranial, 40
Facial, 40
Lambdoid, 16
Metppic, 14
Orbital, 37
Sagittal, 16, 40
Sylvius, Aquaeduct of, 202
Fissure of, 184
Sympathetic System, 236, 268
Symphysis, 33, 59, 64
Synarthrosis, 59
Synovia, 60
Synovial Membranes, 60
Syndesmology, i, 58
Syndesmosis, 59
System, Arterial, 122
Cerebro-spinal Nervous, 178
Chromaffin, 344
System, Chromaphil, 344
Haversian, 4
Lymphatic, 171
Nervous, 175
Phaerochrome, 344
Portal, 170
Sympathetic Nervous, 236, 268
Vascular, 118
Venous, 163
TAPETUM, 283, 286
Tarsi, 294
Tarsus, 57
Taste, Nerves of, 275
Taste-buds, 275
Taenia Hippocampi, 190
Semicircularis, 190
Tectum, 202
Mesencephali, 202
Teeth, 31?
Development of, 319
Eruption of, 320
Tegmentum, 197
Tela Choroidea Inferior, 211
Ventriculi Tertii, 190
Subcutaneous, 74
Telencephalon, 178
Temporal Bone, 19
Tendo Oculi, 294
Tendon of Achilles, 113
Conjoined, 95
Tendons, 74
Tenon's Capsule, 280
Tentqrium Cerebelli, 181
Terminal Organs, 177
Testes, 392
Appendages of, 375
Coverings of, 373
Descent of, 375
Quadrigeminal, 202
Testicle, 392
Thalamencephalon, 192
Thalamus Opticus, 193
Thebesius, Foramena of, 119
Thenar Eminence, 106
Thigh, 112
Thorax, 7, 93, 99
Thymus Gland, 347
Thyro-hyal, 41
Thyroid (or thyreoid) Axis, 131, 152
Cartilage, 350
Gland, 345
Tibia, 54
Tissue, Erectile, 371
Gray Nervous, 176
White Nervous, 177
Todd and Bowman, Muscle of, 309
Tongue, 273
Muscles of, 82, 83
Tonsil, Cerebcllar, 207
Palatine, 314
Pharyngeal, 321
. Tubal, 303
Torcular Herophili, 18, 165
Torus Tubarius, 321
Trabeculse Lienis, 349
Trachea, 355
Tract, see also Fasciculus
428
INDEX
Tract, Anterior (or direct) Pyramidal,
196, 214
Ascending Antero-lateral (Gower's),
205, 214
Caudate-cerebellar, 197
Central Tegmental, 202
Cerebro-spinal, 196, 214
Cortico-pontine, 19?
Crossed Pyramidal, 196, 214
Descending Root of Trigeminus,
201
Direct Cerebellar (Flechsig's), 210,
215
Direct (or anterior) Pyramidal, 196,
214
Flechsig's, 210, 215
Fronto-pontine, 197
Gower's, 205, 214
Indirect Motor, 197
Lissauer's, 215
Mesencephalic Root of Trigeminus,
2OI
Mesencephalo- (or tecto-) Spinal,
199
Monakow's, 201
Motor, Direct, 196
Indirect, 197
Postero-lateral, 215
Pre-pyramidal, 201
Pyramidal, 196
Rolando's, 209
Rubro-spinal, 201
Solitary, 211. 221
Spino-cerebellar, 205, 214
Spino-thalamic, 200
Tecto- (or mesencephalo-) Spinal,
199
Temporo-pontme, 197
Thalamo-olivary, 202
Transverse Peduncular, 180
Uncrossed Pyramidal, 196
Uveal, 281
Ventral Spino-cerebellar, 205, 206
Ventro-lateral Spino-cerebellar, 205,
206
Tractus Spiralis Foraminosus, 311
Tragus, 297
Trapezium Medullas Oblpngatae, 204
Triangle, Anterior, Cervical, 128
Carotid, 129
Femoral, 142
Habenular, 194
Hesselbach's, 387
Interosseous of Fibula, 56
Occipital, 130
Posterior Cervical, 130
Scarpa's, 142
Subclavian, 130
Subcutaneous of Fibula, 56
Submandibular, 129
Submaxillary, 129
Triangles of the Neck, 128
Trigonum Acustici, 212
Collaterale, 191
Femorale, 142
Habenulae, 194
Hypoglossi, 212
Olfactorium, 217
Trigonum Vagi, 212
Vesicse, 367
Triquetrum (cuneiform), 51
Trochanters, 3
of Femur, 53
Trochlea, of Humerus, 48
of the Orbit, 289
Trochlear, 3
Nerve, 217, 244
Trochoides, 59
Tuba Auditiva, 303
Tuba? Uterinae, 382
Tube or Tubes —
Eustachian, 303
Fallopian, 382
Neural, 178
of Shachowa, 362
Tube-tonsil, 303
Tuber Cinereum, 186
Valvulas, 207
Tubercle or Tubercles, 3
Adductor, 54
Amygdaloid, 179
Anterior of the Thalamus, 193
Bicipital, 49
Darwin's, 297
Genial, 34
of Humerus, 47
of Lower, 120
Pharyngeal, 18
Zygomatic, 19
Tuberculum, Acusticum, 212
Auriculae, 297
Intervenosum, 120
Sellse, 22
Tube^sity or Tuberosities, 3
Bicipital, 49
of Femur, 54
of Humerus, 47
of Ischium, 14
Malar, 30
Maxillary, 28
of Palate, 32
of Radius, 49
of Tibia, 54
of Ulna, 49
Tubules or Tubuli—
Convoluted, 362
Dentinal, 319
Lactiferi, 384
Renales, 362
Seminiferi, 374
Spiral, 362
Uriniferi, 362
Tuft, Malpighian, 361
Tunica Albugenia, 374
Conjunctiva, 294
Fibrosa Oculi, 281
Interna Oculi, 285
Ruyschiana, 283
Vaginalis Testis, 374
Vascu^sa Oculi, 283
Testis, 374
Tunics of the Eyeball, 281
of the Testicle, 374
Turbinals, 32
Sphenoidal, 24
Tutamina Oculi, 293
INDEX
429
Tympanic Bone, 21
Tympanum, 300
Tyson's Glands, 372
ULNA, 48
Umbilical Region, 324
Umbilicus, 324
Umbo, 298
Unciform, 3
Uncinate Gyrus, 186
Ungues. 272
Urachus, 366
Ureters, 363
Urethra, Female, 370
Male, 368
Urogenital Diaphragm, 393
Uterus, 380
Appendages of, 382
Masculinus, 368
Utricle, 307
Utriculus Prostaticus, 368
Uvea, 285
Uveal Tract, 281
Uvula, 313
Cerebelli, 207
Vesicae, 367
VAGINA, 379
Vaginal, 3
Process, 21
Vallecula, 206
Valsalva, Sinuses of, 120, 122
Valve of Bauhin, 331, 334
Coronary, 120
Eustachian, 120
of Hasner, 296
Ileo-caecal, 331, 334
Mitral, 121
Pyloric, 329
of Thebesius, 120
Tricuspid, 120
of Vieussens, 203, 207
Valves, Aortic Semilunar, 121
of Houston, 335
of Kirkring, 332
Pulmonary, 120
Semilunar, 120, 122
Valvulae Coli, 334
Conniventes, 332
Sinus Coronarii, 120
Venae Cavae Inferioris, 120
Vas Aberrans, 373
Deferens, 375
Spirale, 309
Vasa Efferentia, 374
Recta, 374
Vasorum, 122
Vein or Veins, 163
Angular, 164
Auricular, 164
Axillary, 166
Azygps, 167
Basilic. 166
Bronchial, 356
Cardiac, 171
Cephalic, 166
Cerebellar, 164
Cerebral, 164
Veins, Choroid, 283
Cystic, 170
Emissary, 165
Facial, 164
Femoral, 168
Frontal, 163
Gastric, 170
Hepatic, 170, 3 2
Iliac, 169
Innominate, 166
Intercostal, 167
Interlobular, 342
Intralobular, 342
£ugular, 165
ienal (splenic), 170
Lobular, 342
Lumbar, 170
Mammary, 167
Maxillary, 164
Median, 166
Mesenteric, 170
Occipital, 164
Ovarian, 170
Phrenic, 170
Popliteal, 1 68
Portal, 170, 341
Pulmonary, 163
Radial, 166
Renal, 170, 363
Saphenous. 168, 169
Spermatic, 170
Spinal, 168
Splenic, 170. 349
Subclavian, 166
Sublobular, 342
Supraorbital, 163
Supra-renal, 170
Temporal, 164
Thyroid, 167
Ulnar, 166
Uterine, 382
Vertebral, 166
Veins of the Abdomen, 169
Bladder, 368
Bone, 4
Diploe, 164
Ear, 312
Head and Neck, 163
Heart, 171
Intestine, 333, 336
Kidney, 363
Larynx, 354
Liver, 341, 342
Lower Extremity, 168
Lung, 359
Mammary Gland, 384
Membrana Tympani, 299
Neck, 165
Nose, 279
(Esophagus, 323
Ovaries, 383
Pancreas, 344
Pelvis, 169
Penis, 372
of Pharynx, 322
Prostate Gland, 37
Rectum, 336
Stomach, 330
43C
INDEX
Veins, Supra-renal Glands, 365
Testicle, 375
Thorax, 167
Thymus Gland, 347
Thyroid Gland, 346
Tongue, 275
Tonsil, 314
Trachea and Bronchi, 356
Tympanic Membrane, 299
Tympanum, 302
Upper Extremity, 166
Uterus, 382
Vagina, 379
Without Valves, 163
Velum, Inferior Medullary, 212
Interpositum, 190
Superior Medullary, 203, 207
Vena Cava, Inferior, 170
Superior, 168
Venae Comites, 163
Galense, 185
Proprise Renales, 363
Rectae, 363
Vorticosae, 290
Venous Sinuses, 163
System, 163
Portal, 170
Pulmonary, 163
Systemic, 163
Ventricle of Cerebellum, 211
Lateral, 189
Fifth, 191
Fourth, 211
Laryngeal, 354
Nasal, 277
Third, 189, 192
Ventriculus, 328
Vermis Cerebelli, 206
Superior, 207
Vertebrae, 5
Important Relations of, 7
Vertebral Aponeurosis, 90
Verumontanum, 368
Vesica Fellea, 3^3
Urinaria, 365
Vesicle, Graafian, 383
Vesicles of the Brain, 178
Seminal, 376
Vestibule of the Ear, 305
of the Larynx, 353
of the Mouth, 312
of the Nose, 277
of the Vulva, 378
Vidian Canal, 25
Vieussens, Valve of, 203, 207
Villi of the Intestine, 332
Vinculum Lingua?, 207
Viscera covered by Peritoneum, 327
Vocal Cords, 353
Vomer, 33
Vortex of the Heart, 118
Vulva, 377
WAGNER'S Corpuscles, 177
Wharton's Duct, 316
White Matter of the Brain, 179
Rami Communicantes, 227
Willis, Circle of, 128, 151
Winslow's Foramen, 326
Ligament, 70
Wirsung's Duct, 344
Worm, 207
Wormian Bones, 3, 40
Wrisberg's Cartilage, 352
Ganglion, 239
Ligament, 71
Nerve, 229
XYPHOID Appendix, 8
YELLOW Spot, 285
ZINN, Ligament of, 76
Zonule, 288
Zona Arcuata, 309
Pectinate, 309
Zonula Ciliaris, 288
Zonule of Zinn, 288
Zygapophyses, 5
Zygoma, 19
Zygomatic Bone, 30
2A>V0J^ cp&.
(T
;WU
,)
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UNDERBILL— TOXICOLOGY, 2d EDITION
By Frank P. Underbill. Ph.D., Professor of Pharmacology and Toxicology, Yale
University. Cloth, $2.50.
BRUBAKER— A TEXT-BOOK OF HUMAN PHYSIOLOGY. 8th EDITION
By Albert P. Brubaker, A.M., M.D., Professor of Physiology and Hygiene.
Jefferson Medical College. Colored Plate and 367 Illustrations. Cloth, $5.00.
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