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MEDICAL *§CH©(DL

Gift of ALICE F. MAXWELL, M.D,

THE

POCKET ANATOMY

SIXTH EDITION, REVISED AND EDITED

BY

C. H.1FAGGE, M.B., M.S. LOND., F.R.C.S.

THIRTIETH THOUSAND

N E W YORK

WILLIAM WOOD & COMPANY MDCCCCVIII

PREFACE

IN compiling this edition I have borrowed from Quain's 'Anatomy,' Cunningham's 'Text-book of Anatomy,' and Morris's 'Treatise of Anatomy.' It therefore seems that the old name of ' The Pocket Gray ' no longer accurately describes this little volume, so on the advice of the pub- lishers it has been altered to that of ' The Pocket Anatomy.' The whole book has been carefully revised, and many descriptions have been changed, among which the chief is the substitution of Jonnesco's account of the iliac and pelvic colon and rectum for that of the sigmoid and rectum of previous editions.

C. H. FAGGE.

3, DEVONSHIRE PLACE, LONDON, W.

5954".

THE POCKET ANATOMY

THE ARTICULATIONS.

The Classification of Joints.

Synarthrosis (Immovable Joint). Varieties : —

Sutura.

Suit-varieties : — S. Dentata. S. Serrata. S. Limbosa. S. Squamosa. S. Harmonia.

Synchondrosis— may become a Synostosis. Schindylesis. Gomphosis.

Amphiarthrosis (allowing slight movement). Varieties : —

Symphysis. Syndesmosis.

Diarthrosis (Movable Joint). Varieties :—

Arthrodia, or Gliding Joint.

Enarthrosis, or Ball-and-Socket Joint.

Ginglymus, or Hinge Joint.

Condyloid.

Reciprocal Reception, or Saddle Joint.

Trochoid, or Pivot Joint.

ARTICULATIONS OF THE TRUNK.

I. — ARTICULATIONS OF THE VERTEBRAL COLUMN.

(A ) Joints between the bodies which are amphiarthroses. (J3) Joints between the neural arches by means of the

2 THE POCKET ANATOMY

articular processes which are diarthroses of the arthrodial variety.

(A) The Ligaments of the Bodies.

The anterior common ligament : a broad band of fibres, extending along front of bodies of vertebras, from axis to sacrum. It consists of two sets of fibres, superficial and deep ; the former extending between the bodies of two or more vertebras, the latter only between adjacent vertebras. The fibres are attached principally to the intervertebral sub- stances.

The posterior common ligament is within the spinal canal, and extends along back of bodies of the vertebras from axis to sacrum, being broad opposite the intervertebral discs, and narrow opposite the bodies, except in the neck, where it is as wide as the bodies. It is attached to the discs and contiguous parts of the bodies of the vertebrae.

The intervertebral substances, found between the vertebrae from axis to sacrum. The circumference of each consists of layers of oblique parallel fibres of white fibrous tissue, en- closing a central part of pulpy elastic material. They are thickest in the lumbar region, and they give the peculiar curves to the column by their differences in thickness.

(B) The Ligaments of the Lamina.

The ligamenta subflava connect the laminae of the vertebrae from the axis to the sacrum. Each ligament is attached to the anterior inferior edge of the lamina above, and to thf posterior superior edge of the lamina below.

The Ligaments of the Articular Processes.

Capsular ligaments surround the articular processes, those in the cervical region being the loosest. Each is lined by a synovial membrane.

The Ligaments of the Spinous Processes.

The interspinous ligaments extend in all regions of the vertebral column between the spinous processes of the ver- tebras, running from root to apex.

The supraspinous ligament: a fibrous cord, joining the tips of the vertebrae, and extending from the seventh cervical to the first sacral.

The ligamentum nuchse continues the supraspinous liga- ment upwards. It consists of a superficial layer, extending from the spine of the seventh cervical to the external occipital protuberance, and a deep layer attached to the spines of the cervical vertebrae and the occipital crest.

The Ligaments of the Transverse Processes.

Intertransverse ligaments extend between the transverse

A RTIC ULA TIONS 3

processes, often absent in the cervical, thin in the lumbar, but round and well marked in the dorsal region.

II.— ARTICULATION OF ATLAS WITH AXIS.

The atlo-axoid articulation consists of four joints — (a) a pivot joint consisting of two parts, (i.) between odontoid pro- cess and anterior arch of atlas, and (ii.) between odontoid process and transverse ligament ; (b) two arthrodial, between the articular processes.

The anterior atlo-axoid ligament consists of a superficial and a deep part. The superficial part continues the anterior common ligament. It is attached above to the anterior tubercle of the atlas ; and below to the body of the axis and base of the odontoid process. The deep part is broad, and reaches from the lower border of the anterior arch of atlas to the base of odontoid process and body of axis.

The posterior atlo-axoid ligament : a thin layer, connected above to the lower border of the posterior arch of atlas, and below to the upper edge of laminas of axis, pierced by the second cervical nerve.

The transverse ligament keeps the odontoid process in its place ; it is attached on each side to a tubercle on the inner surface of the superior auricular process of the atlas. A thin bundle of fibres passes upwards from the middle of the pos- terior surface to the basilar process, and a like process down- wards to the body of the axis. These two processes, together with the transverse ligament, form the cruciform ligament.

Capsular ligaments as in ordinary vertebrae, but supple- mented at the posterior and inner part by an accessory liga- ment passing downwards and inwards to the base of the odontoid process (accessory atlo-axoid ligaments').

Synovial membranes : besides those of capsular ligaments, two ; one in front and one behind the odontoid process, the latter often communicating laterally with one of the occipito- atloid joints.

HI. — ARTICULATION OF ATLAS WITH OCCIPITAL BONE.

The anterior occipito-atloid ligament consists of a super- ficial and a deep part. The superficial, rounded, pa'sses from the basilar process of the occiput to the anterior tubercle of the atlas. The deep part is broad, and attached above to the anterioredge of the foramen magnum, and below to the upper margin of anterior arch of atlas.

X — 2

4 THE POCKET ANATOMY

The posterior occipito-atloid ligament, thin and mem- branous, is attached above to posterior margin of foramen magnum ; below, to upper border of posterior arch of atlas. (Perforated on each side by vertebral artery and subocdpital or first cervical nerve. )

The lateral occipito-atloid ligaments : one on each side ; attached above to the jugular process of occiput, and below to the base of atlantal transverse process.

Capsular ligaments as in ordinary vertebrae.

IV. — LIGAMENTS BETWEEN THE AXIS AND OCCIPITAL BONE.

The occipito-axoid ligament (apparatus ligamentosus colli) : a continuation of the posterior common ligament, connected above with basilar groove of occiput, and below to posterior surface of the body of axis.

The odontoid or check ligaments consist of two cords passing from the sides of the apex of the odontoid process to the rough surface on the inner side of each condyle of the occipital bone. In the interval between the two the ligamen- tum suspensorium dentis passes from the apex of the odontoid process to the anterior margin of the foramen magnum.

V. — TEMPORO-M AXILLARY ARTICULATION.

The condyle of the lower jaw articulates with the anterior part of the glenoid fossa, and with the eminentia articularis of the temporal bone, the joint being divided into an upper and a lower synovial cavity by an interarticular fibro-cartilage.

The external lateral ligament, attached above to tubercle and lower border of zygoma ; below, to outer surface and posterior edge of neck of lower jaw.

The internal lateral ligament is attached above to the spinous process of the sphenoid, and below to the inner margin or lingula of the dental foramen of lower jaw.

The capsular ligament : thin and loose, attached above to the edge of anterior half of glenoid cavity and articular eminence ; below, it surrounds neck of the condyle.

The interarticular fibro-cartilage has an oval shape ; the upper surface is concavo-convex from before backwards, and slightly convex transversely ; the lower surface is concave ; the edge4 is attached to the capsule, and part of the external pterygoid muscle is inserted into its anterior margin.

Synovial membranes, two in number, one above and one below the fibro-cartilage ; the upper being the larger.

The stylo-maxillary ligament: a band of fibrous tissue

ARTICULATIONS 5

extending from the styloid process to angle and posterior border of ramus of the jaw, which is derived from the deep cervical fascia (p. 26).

(Stylo -hyoid ligament: a fibrous cord extending from the styloid process to small cornu of hyoid bone).

VI. — ARTICULATION OF THE RIBS WITH THE VERTEBRA.

(a) Articulations between the Heads of the Ribs and the Bodies of the Vertebra.

Arthrodial joints held together by the following ligaments : —

The anterior costo-vertebral or stellate ligament is com- posed of three fasciculi, which radiate from the anterior surface of the head of the rib. The superior fasciculus passes to the body of the vertebra above ; the inferior fasciculus to the body of the vertebra below ; the middle fasciculus to the interverte- bral substance.

A capsular ligament surrounds articulation between the head of the rib and the articular surface formed by two vertebrae.

The interarticular ligament divides the joint into two parts, each of which has a separate synovial membrane. It passes between ridge on head of rib and intervertebral substance. (Absent in the ist, loth, nth, and iath ribs.)

(b) Articulations of the Necks and Tubercles of the Ribs with the Transverse Processes of the Vertebra.

Arthrodial joints held together by the following ligaments:

The anterior or superior costo-transverse ligament passes from the upper border of neck of rib, to lower border of transverse process above. (Absent in ist rib.)

The middle costo-transverse or interosseous ligament : a short thick band passing from the anterior surface of the transverse process to the posterior surface of neck of corre- sponding rib. (Rudimentary in nth and iath ribs.)

The posterior costo-transverse ligament passes from apex of transverse process to rough non-articular part of tubercle of rib. (Absent in nth and i2th ribs.)

The capsular ligament surrounds articular surfaces, en- closing a small synovial membrane. (This articulation is absent in the nth and i2th ribs.)

VII. — ARTICULATION OF THE UPPER SEVEN COSTAL CARTILAGES WITH THE STERNUM.

The anterior chondro-sternal ligament : a broad thin band, radiating from extremity of the rib cartilage to the sternum.

6 THE POCKET ANATOMY

The superior fasciculi pass obliquely upwards, the inferior downwards, and the middle horizontally.

The posterior chondro-sternal ligament is an indistinct band of fibres radiating from the posterior surface of the inner end of the costal cartilage to the back of the sternum.

The capsular ligament surrounds the joint, and encloses a synovial membrane (In the ist there is no synovial mem- brane ; in the 2nd and 3rd there are 2, the joint being divided by an interarticular ligament passing between end of the costal cartilage and cartilage between adjacent pieces of the sternum. (The 4th, 5th, 6th, and yth have one each.)

VIII. — ARTICULATIONS OF THE CARTILAGES OF THE RIBS WITH EACH OTHER.

The cartilages of the 6th, yth, and 8th ribs articulate with each other by an oval shaped facet, each having a capsule enclosing a synovial membrane.

IX.— ARTICULATIONS OF THE RIBS WITH THEIR CARTILAGES.

The costal end of each cartilage fits into a depression in the sternal end of the rib, and is bound down by periosteum.

X.— ARTICULATIONS OF THE STERNUM.

The ist and 2nd pieces are united by a piece of cartilage, kept together by the following two ligaments : —

The anterior intersternal ligament consists of longitudinal fibres, which blend with the costo-sternal ligaments.

The posterior intersternal ligament: similar to the pre- ceding, placed on the back of the sternum.

XI. —ARTICULATION OF THE PELVIS WITH THE SPINE.

The following ligamentsconnect the 5th lumbar vertebra with the sacrum, and are similar to the common vertebral ones :—

1. The continuations of the anterior and posterior common ligaments.

2. The intervertebral substance between the last lumbar vertebra and the sacrum.

3. The ligamenta subflava between the laminae of the last lumbar vertebra and the margins of upper opening of the sacral canal.

4. Capsular ligaments, between the articular processes.

5. Interspinous and supraspinous ligaments.

Besides these, there are the following special ligaments : The lumbo-sacral or sacro-vertebral ligament: attached above to the front of tip of transverse process of the 5th

ARTICULATIONS 7

lumbar vertebra; below, to the outer border of the front of the lateral mass of the sacrum.

The ilio-lumbar ligament passes from the tip of transverse process of 5th lumbar vertebra, to the crest of L.um in front of sacro-iliac articulation.

XII. — ARTICULATIONS OF THE PELVIS.

(a) Sacro-iliac Joint.

The sacro-iliac articulation is an amphiarthrosis, formed between the lateral surfaces of the sacrum and ilium. The auricular or anterior parts of the articular surfaces are covered with cartilage, and connected by the two following ligaments : —

The anterior sacro-iliac ligament : small bands passing obliquely from sacrum to ilium on the anterior surface.

The posterior sacro-iliac ligament consists of strong inter- osseous bands passing chiefly downwards and inwards from the rough part of the ilium behind the cartilage, to the posterior part of the sacrum. There are two superior, passing from the ist and 2nd transverse sacral tubercles, and one sometimes called the oblique sacro-iliac ligament, which reaches from the posterior superior iliac spine to the 3rd transverse sacral tubercle.

(b) Ligaments between the Sacrum and Ischium.

The great (or posterior] sacro-sciatic ligament, attached by its base to the posterior inferior iliac spine, to the 4th and 5th transverse sacral tubercles, and to the lower part of the edge of the sacrum and coccyx ; passes downwards, outwards, and forwards, to be attached to the inner edge of the ischial tuberosity and to the inner margin of the ramus, forming the falciform ligament.

The small (or anterior] sacrp-sciatic ligament, attached by its apex to the spine of the ischium, and by its base to the lateral margin of the coccyx and sacrum.

Foramina. — Between the great sacro-sciatic ligament and the innominate bone is a space divided into two by the small sacro-sciatic ligament ; the part above this ligament being the great sacro-sciatic foramen, and the part between the two liga- ments the small sacro-sciatic foramen. The large foramen transmits pyriformis, together with superior gluteal, sciatic and internal pudic vessels, the superior gluteal, great and small sciatic, pudic and inferior gluteal nerves, and nerves to the obturator internus, quadratus, and gemelli. The small foramen transmits the obturator internus, whilst its nerve, together with the internal pudic vessels and pudic nerve, re- enters the pelvis by it.

8 THE POCKET ANATOMY

(c) Articulation of the Sacrum and Coccyx. Araphiarthrodial joint.

The anterior sacro-coccygeal ligament, very indistinct, passes from anterior surface of sacrum to that of the coccyx.

The posterior sacro-coccygeal ligament passes from the margin of the lower orifice of the sacral canal to the posterior surface of the coccyx.

Interarticular ligaments between the cornua. Lateral ligaments, passing from the lower lateral angle of sacrum to transverse process of ist piece of coccyx.

A fibro-cartilage is placed between the sacrum and the coccyx.

(d) Symphysis Pubis.

Amphiarthrodial joint bound together by the following ligaments : —

The anterior pubic ligament consists of several layers of fibres crossing the symphysis horizontally in front.

The posterior pubic ligament resembles the anterior, but is much less distinct, and connects the bones posteriorly.

The superior pubic ligament connects the bones superiorly.

The sub-pubic ligament, forming the upper boundary of the pubic arch, is a thick triangular arch of fibres, attached above to the fibro-cartilage, and laterally to the rami.

The fibro-cartilage consists of two parts, one on each bone ; the two are united in front, but posteriorly they are separated by a small cavity lined by a synovial membrane.

ARTICULATIONS OF THE UPPER EXTREMITY.

I. — STERNO-CLAVICULAR ARTICULATION.

An arthrodial joint between the inner end of the clavicle and the ist piece of sternum and ist costal cartilage, con- nected together by the following ligaments :

The anterior sterno-clavicular ligament is attached to upper and anterior part of the inner end of the clavicle, and to the upper and anterior part of the ist piece of the sternum.

The posterior sterno-clavicular ligament passes between the inner end of the clavicle and the sternum on the posterior surface.

The interclavicular ligament passes along the top of the sternum from the inner end of one clavicle to the other.

ARTICULATIONS 9

The costo-clavicular or rhomboid ligament : a strong band of fibres passing backwards, upwards, and outwards from the upper surface of the sternal end of ist costal cartilage, to a rough marking on the under surface of the inner end of the clavicle.

The interarticular fibro-cartilage is a nearly circular plate, thicker at the circumference than in the centre. It is attached above to the upper border of the clavicle, and below to the ist costal cartilage at its junction with the sternum. There are two synovial membranes, one on each side of the cartilage.

II. — SCAPULO-CLAVICULAR ARTICULATION.

(a) Acrormo-clavicular, an arthrodial joint held together by the following ligaments : —

The superior acromio-clavicular ligament passes between the outer end of the clavicle and the upper surface of the acromion.

The inferior acromio-clavicular ligament covers the joint below, being attached to the clavicle internally, and the acro- mion externally.

An interarticular fibro-cartilage, rarely complete, usually occupies the upper half of the joint. When it is complete, there are two synovial membranes.

(ft) The toraco-clavicular ligaments connect the clavicle and the coracoid process of the scapula ; they are : —

The trapezoid ligament (the anterior and external one) : attached below to the posterior half of the upper surface of the coracoid process, and above to the oblique line on the under service of the clavicle. It is in contact posteriorly with the conoid ligament.

The conoid ligament (the posterior and internal one) is attached above by its base, to the conoid tubercle on the inferior surface of the clavicle, and the contiguous part ; by its apex to a rough depression at the base of the coracoid process.

III.— PROPER SCAPULAR LIGAMENTS.

The coraco-acromial ligament passes over the shoulder- joint between the coracoid and acromion processes. Ex- ternally it is attached to the tip of the acromion, and internally to all the outer border of the coracoid process.

The transverse or suprascapular ligament stretches over the notch on the upper border of the scapula, and converts it into a foramen.

10 THE POCKET ANATOMY

IV. — THE SHOULDER-JOINT.

This joint between the head of the humerus and the glenoid cavity is an enarthrodial or ball-and-socket joint. The long tendon of the biceps acts as a ligament to this joint.

The capsular ligament is attached to the circumference of the glenoid cavity, and to the neck (anatomical) of the humerus. It is very loose, and permits free movement of the joint. There is generally an aperture on the inner side, through which a piece of the synovial pouch protrudes to form the bursa under the subscapularis.

The coraco humeral or accessory ligament helps to strengthen the capsule ; it is attached to the outer border and base of the coracoid process, and below to the neck of humerus, above great tuberosity, and it blends with the cap- sule at the margins of the bicipital groove.

Gleno-humeral ligaments, seen as three folds on inner aspect of joint : —

The superior or Flood's ligament passes along inner edge of biceps tendon from glenoid ligament to depression on lesser tuberosity at inner margin of the bicipital groove.

Middle : oblique, arises with superior, runs downwards forming lower margin of aperture for subscapularis bursa to lesser tuberosity.

The inferior or Schlemm's ligament passes from the lower part of the glenoid cavity to the neck of humerus on the inner side of the small tuberosity.

The glenoid ligament is a dense fibrous band attached to the edge of the glenoid. cavity to deepen it, and is con- tinuous with tendon of the long head of the biceps.

Transverse over bicipital groove.

A synovial membrane lines the joint, and protrudes to form the bursa under the subscapularis. It is reflected round the tendon of the biceps, and lines the bicipital groove.

Subacromial bursa beneath acromion and deltoid, and over supraspinatus and capsule.

V. — THE ELBOW-JOINT.

The elbow is a ginglymus or hinge-joint, between the trochlear surface of the humerus and the greater sigmoid cavity of the ulna, combined with an arthrodial joint between the capitellum of the humerus and the upper end of the radius.

The anterior ligament is attached, above to the front of

ARTICULATIONS i,

the humerus just above the coronoid fossa ; and below to the coronoid process, and the front of orbicular ligament.

The posterior ligament is attached, above to the upper border of the olecranon fossa ; below, to the margin of the olecranon.

The internal lateral ligament is triangular in shape ; it is attached, above to the inner condyle of the humerus ; the fibres diverge as they descend, the anterior ones going to the inner margin of the coronoid process, the posterior to the inner margin of the olecranon.

The external lateral ligament, smaller than the preceding, is attached, above to a depression below the external condyle, and below to the orbicular ligament, some of the fibres being prolonged to the outer edge of the ulna.

The synovial membrane is very large, covering the articular surfaces of the humerus, ulna, and radius ; it also serves for the upper radio-ulnar articulation.

VI. — THE RADIO-ULNAR ARTICULATIONS.

(a) Superior Radio-ulnar Articulation (lateral ginglyinus). The orbicular ligament surrounds the head of the radius.

It is attached to the two ends of the lesser sigmoid cavity, and is wider above than below. The outer surface is con- nected with the external lateral ligament. The internal surface is lined with synovial membrane continuous with that of the elbow-joint.

(b) Middle Radio-ulnar Articulation.

The oblique or round ligament is a fibrous cord passing downwards and outwards from the tubercle at the base of the coronoid process, to a little below the tubercle of the radius.

The interosseous membrane passes downwards and inwards (the opposite to the preceding) from the radius to the ulna ; it is attached to the interosseous border of each bone.

(c) Inferior Radio-ulnar Articulation (lateral ginglymus). The anterior radio ulnar ligament passes from the anterior

edge of the radial sigmoid cavity to the anterior surface of the head of ulna.

The posterior radio-ulnar ligament extends similarly upon the posterior surface.

The triangular fibro cartilage passes transversely beneath the lower end of the ulna, between its styloid process and the radius. Its apex is attached to the outer side of base of the styloid process of ulna, and the base to the edge of the radius between the sigmoid cavity and the lower articular surface.

12 THE POCKET ANATOMY

The synovial membrane (membrana sacciformis) is very loose, and lines the contiguous surfaces of the radius and ulna, together with the upper surface of the triangular cartilage ; sometimes communicates with the synovial sac of wrist-joint.

,' '

VII. — THE WRIST-JOINT.

The wrist-joint is a condyloid joint, formed by the lower end of the radius and the triangular fibro-cartilage above ; and by the scaphoid, semilunar and cuneiform bones below. It is united by the following ligaments : —

The external lateral ligament passes from the tip of the styloid process of the radius to a depression on the outer surface of the scaphoid bone.

The internal lateral ligament, a fibrous cord, passes from the end of the styloid process of the ulna, and dividing into two, one part is attached to the pisiform bone, and the other to the inner side of the cuneiform bone.

The anterior ligament, broad and membranous, consists of three bundles of fibres, springing from the anterior edge of the lower end of radius, and the styloid process of the ulna ; below it is fixed into the anterior surfaces of the scaphoid, semilunar and cuneiform bones, some fibres being continued to the os magnum.

The posterior ligament, weaker than the preceding, springs from the posterior margin of the lower end of the radius, and is attached to the dorsal surfaces of the scaphoid, semilunar, and cuneiform bones.

A synovial membrane lines the joint.

VIII. — ARTICULATIONS OF THE CARPUS.

Articulations of the ist Row of Carpal Bones, the pisiform excepted (arthrodial) .

The dorsal ligaments pass transversely between the scaphoid and semilunar, the semilunar and the cuneiform.

The palmar ligaments connect the bones similarly upon the anterior surface.

The interosseous ligaments (2) close the upper part of the intervals between the scaphoid and semilunar, the semilunar and cuneiform bones.

Articulations of the 2nd Row of Carpal Bones (arthrodial).

The dorsal ligaments (3) pass transversely from bone to hone as in the ist row.

The palmar ligaments (3), similar to those of the ist row

ARTICULATIONS 13

The interosseoue ligaments (3) are thicker than those of the ist row, and connect the os magnum and the trapezoid, the os magnum and the unciform bones and the trapezium and trapezoid.

A rticulations of the two Rows of Carpal Bones together.

The anterior or palmar ligaments pass from the front of the ist row to the palmar surface of the os magnum.

The posterior or dorsal ligaments are similarly placed upon the dorsal surface.

The lateral ligaments : the external connects the scaphoid and trapezium bones ; the internal the cuneiform and unciform.

The synovial membrane is large ; it lines the under surface of the bones of the ist row, except the pisiform bone, and is reflected between their contiguous surfaces; it then passes between the bones of the 2nd row, and lines their contiguous surfaces, usually giving reflections between the carpal ends of the four inner metacarpal i bones, and between the con- tiguous surfaces of the trapezium and 2nd metacarpal bone.

The pisiform bone is connected to the cuneiform by a thin capsule lined by a synovial membrane ; and inferiorly to the unciform and 5th metacarpal bones.

The anterior annular ligament extends from the trapezium and scaphoid across to the unciform process and pisiform bone.

The posterior annular ligament extends from the outer border of lower end of radius, to inner side of cuneiform and pisiform bones.

IX. — CARPO-METACARPAL ARTICULATION.

The Articulation of the Trapezium and ist Metacarpal.

Reciprocal reception joint.

The capsular ligament, thick and loose, passes from the upper end of the ist metacarpal to the rough edge round the articular surface of the trapezium. It is lined by a separate synovial membrane.

Articulations of the Carpus and the rest of the Metacarpus.

The dorsal ligaments connect the carpal with the meta- carpal bones on the posterior surface ; each metacarpal receives two fasciculi, except the 5th, which has only one.

The palmar ligaments are similarly arranged on the anterior surface, except that the 3rd metacarpal has three fasciculi.

The interosseous ligaments connect the os magnum and unciform bones to the 3rd and 4th metacarpal bones.

The synovial membrane is continuous with that between ;he two rows of carpal bones, and has been described above.

14 THE POCKET ANATOMY

Articulations of the Metacarpal Bones with each other.

The carpal ends are united by dorsal and palmar ligaments passing transversely.

The interosseous ligaments pass between the bones beneath the level of the articular facets. The synovial membrane is con- tinuous with that between the two rows of carpal bones.

The digital extremities of the four inner metacarpals are connected by the transverse metacarpal ligament, which blends with the palmar surface of each metacarpo-phalangeal articu- lation.

X. — METACARPO-PHALANGEAL ARTICULATIONS.

Condyloid joint.

The palmar ligament is a thick plate of fibro-cartilage, at- tached to the head of the metacarpal bone and the base of the ist phalanx : laterally it blends with the lateral ligaments.

The lateral ligaments, one on each side, attached above to the posterior tubercle and depression on the side of the head of the metacarpal bone, and below to the side of the ist phalanx.

A synovial membrane lines the joint.

XI. ARTICULATIONS OF THE PHALANGES.

Each of these is a small ginglymus or hinge joint, con- nected by a palmar and two lateral ligaments, and lined by a synovial membrane.

ARTICULATIONS OF THE LOWER LIMB.

I. — THE HIP-JOINT.

This is an enarthrodial joint, formed by the head of the femur and the acetabulum. The ligaments are : —

The capsular ligament, very strong and fibrous, arises above from the rim of the acetabulum, just external to the cotyloid ligament, and from the transverse ligament as it bridges the cotyloid notch : below it is attached to the neck of the femur, in front to the anterior intertrochanteric line, superiorly to the root of the neck, and posteriorly to the middle of the neck of the bone, where many of its fibres are reflected upwards upon the neck as the retinacula. The fibres are circular and longitudinal. The circular are most distinct at the lower and posterior part, forming a collar at the lower and back part of the joint, known as the zona orbicularis. The longitudinal fibres form thick bands known as accessory liga- ments. There is often an opening in front of the capsule for

ARTICULATIONS 15

* a protrusion of the synovial membrane to form the bursa under the psoas.

The ilio-femoral ligament ( Y ligament of Bigelow] is accessory to the capsule. It is attached above to the anterior inferior iliac spine, and below it bifurcates and is attached to the anterior intertrochanteric line at its outer and inner parts.

Ischio-capsular ligament (accessory), from ischium below acetabulum, to the circular fibres at the lower and back part of the capsule.

Pubo-femoral ligament (accessory) passes from the ilio- pectineal eminence to the rough tubercle in front of the trochanter minor.

The ligamentum teres passes from the depression on the head of the femur and spreads out to be attached to the margins of the rough depression at the bottom of the aceta- bulum. It consists of connective tissue and vessels, covered with a reflection of synovial membrane.

The cotyloid ligament, a dense fibre-cartilaginous rim, prismatic on section, is attached to the edge of the aceta- bulum, and to the transverse ligament.

The transverse ligament is a narrow band which crosses the cotyloid notch ; the nutrient vessels to the joint pass under it.

The synovial membrane is single, and is reflected over the inner surface of the capsule on to the neck of the femur, thence over the ligamentum teres to the bottom of the acetabulum, where it loosely covers some fat. (Frequently communicates with bursa under ilio-psoas tendon.)

II. — THE KNEE-JOINT.

This is a ginglymus, and is formed by the condyles of the femur, the head of the tibia, and the patella.

The anterior or ligamentum patellae is the continuation of the tendon of the quadriceps extensor. Above it arises from the apex and rough marking on the lower and posterior sur- face of the patella ; below it is attached to the lower part of the tubercle of the tibia. There is a bursa between the upper part of the tubercle and the ligament.

The posterior ligament (ligamentum posticum Winslowii], broad and thin, covers the back of the joint : it springs above from the femur above the condyles, and is attached below to the head of the tibia. From the semi-membranosus tendon it receives a strong expansion, which passes superficially from the inner tuberosity of the tibia to the inner side of the upper part of the outer condyle of the femur.

16 THE POCKET ANATOMY

The internal lateral ligament, broad and flat, is attached above to the inner condyle of the femur ; below to the margin of the inner tuberosity, and to the inner surface of the shaft of the tibia for i£ inches.

The long external lateral ligament, a rounded cord, is attached above to the external condyle of the femur, and below to the external part of the head of the fibula, dividing the biceps tendon into two parts, a bursa intervening.

The short external lateral ligament, very indistinct, lies parallel and behind the preceding, attached above to the outer condyle of the femur, and below to the styloid process of the fibula.

The capsular ligament, thin, fills up the intervals between the special ligaments ; it is attached to the margins of the articular surfaces of the bones, and blends with the fascia lata of the thigh : above it receives expansions from the vasti (lateral patellar ligaments).

Inter articular Structures : —

The anterior or external crucial ligament is attached to the depression in front of the spine of the tibia and to the external semilunar fibro-cartilage ; it passes upwards, back- wards, and outwards to the posterior part of the inner side of the external condyle of the femur.

The posterior or internal crucial ligament is attached to a depression behind the spine of the tibia, to the popliteal notch, and the posterior border of external semilunar fibro- cartilage, this latter slip being sometimes called the ligament of Wrisberg ; it passes upwards, forwards, and inwards, the posterior fibres attached by side of oblique curve of inner con- dyle, the anterior ones to fore part of intercondylar fossa and to the anterior part of the outer surface of the inner condyle.

The semilunar cartilages are thicker at the circumferences than at the central margins, and serve to deepen the cavities for the head of the femur.

The internal semilunar cartilage is oval in shape, the antero-posterior diameter being the longer. Its anterior ex- tremity is attached to the tibia in front of the anterior crucial ligament, and the posterior extremity in front of the posterior crucial ligament.

The external semilunar cartilage is nearly circular : its anterior extremity is attached to the tibia in front of the spine, the posterior extremity to the back of the spine.

In shape the cartilages may be described thus : the internal as a smaller segment of a larger circle, and the external as a larger segment of a smaller circle.

ARTICULATIONS 17

Structures on the Head of the Tibia in the middle line from before backwards : —

1. Transverse ligament.

2. Anterior extremity of in-

ternal semilunar cartilage.

3. Anterior crucial ligament.

4. Anterior extremity of ex-

ternal semilunar cartilage.

5. The spine of tibia.

6. Posterior extremity of ex-

ternal semilunar cartilage.

7. Posterior extremity of in-

ternal semilunar cartilage.

8. Posterior crucial ligament.

The transverse ligament is a band of fibres which passes between the anterior extremities of the semilunar cartilages.

The coronary ligaments bind down the circumferences of the semilunar cartilages to the head of the tibia.

The synovial membrane is the largest in the body. It ex- tends 2 inches above the articular end of femur under the extensors ; thence it passes over the crucial ligaments to the head of the tibia, where it covers both surfaces of the semi- lunar cartilages, and lastly it lines the capsule. It also gives a covering to the popliteus tendon, where it lies within the capsule, and usually communicates with a bursa under the inner tendon of the gastrocnemius and between this tendon and that of the semi-membranosus.

The ligamentum mucosum is a triangular fold of the synovial membrane, attached to the intercondyloid notch, and reaching to the patella.

The ligamenta alaria are two fringes of the synovial mem- brane, seen on either side of the ligamentum mucosum.

III. — THE TIBIO-FIBULAR ARTICULATIONS.

(a) The Superior Tibio-fibular Articulations (arthrodial). The anterior superior ligament passes from the head of

the fibula upwards and inwards to the external tuberosity of the tibia.

The posterior superior ligament passes from the back part of the head of the fibula to the back part of the external tuberosity of the fibula.

A synovial membrane lines the joint.

(b) The Middle Tibio-fibular A rticulation consists of the inter- osseous membrane, the fibres passing down from the tibia to the fibula, being attached to the interosseous ridges on the bones. Superiorly, there is an opening for the anterior tibial vessels ; and inferiorly, one for the anterior peroneal vessels.

(c) The Inferior Tibio-fibular Articulation.

The inferior interosseous ligament passes between the contiguous rough surfaces of the tibia and fibula, and is con- tinuous above with the interosseous membrane.

1 8 THE POCKET ANATOMY

The anterior ligament is triangular in shape, and passes' between the adjacent margins of the tibia and fibula.

The posterior ligament is similarly placed upon the posterior part of the articulation.

The transverse or inferior ligament lies deep to the pre- ceding, passing transversely across the back of the joint, from (lie external malleolus nearly to the internal malleolus, and s jrves to deepen the ankle-joint.

The synovial membrane is continuous with that of the ankle-joint.

IV. — THE ANKLE-JOINT.

This is a ginglymus or hinge joint ; the lower ends of the nbia and fibula embracing the upper articular surface of the astragalus.

The anterior ligament, broad and thin, is connected above with the edge of the articular surface of the tibia, and below with the margin of the superior articular surface of the astra- galus.

The posterior ligament consists principally of transverse fibres, which blend above with the transverse ligament of the inferiortibio-fibular articulation, and are attached to the back part of the upper articular surface of the astragalus.

The internal lateral or deltoid ligament consists of two parts. The superficial part is attached by its apex to the internal malleolus, and by its base posteriorly to the inner side of the astragalus, the sustentaculi tali, and anteriorly to the tuberosity of the scaphoid, blending with the inferior calcaneo-scaphoid ligament. The deep part passes from the apex of the inner malleolus to the inner side of the astragalus.

The external lateral ligament consists of three bundles of fibres. The anterior slip passes between the front of the external malleolus and the side of the astragalus in front of the superior articular process. The middle passes from the apex of the outer malleolus to the middle of the outer side of the os calcis. The posterior is attached to the bone just behind the deep groove on the posterior part of the outer malleolus, running transversely inwards to a depression on the posterior surface of the astragalus.

The synovial membrane lines the inner surface of the ligaments, and is reflected on to the articular surfaces of" the bones. It also lines the inferior tibio-fibular articula- tion.

ARTICULATIONS 19

V. — ARTICULATIONS OF THE TARSUS.

These are arthrodial joints.

Articulations between the Cakanewn and Astragalus.

There are two articulations between the calcaneum and the astragalus : a posterior one, peculiar to the two bones, and an anterior one, common to them and the scaphoid bone ; they are separated by the interosseous ligament.

The external calcaneo-astragaloid ligament passes from outer surface of the astragalus just below the external malle- olus, to the outer surface of the os calcis.

The posterior calcaneo-astragaloid ligament connects the posterior parts of the two bones.

The interosseous ligament consists of a strong thick band passing from the groove between the articulating surfaces of the astragalus to a corresponding groove on the os calcis.

Articulation between Calcaneum and Scaphoid.

The superior calcaneo-scaphoid ligament arises from the groove between the astragalus and os calcis, being blended here with the internal calcaneo-cuboid ligament, and passes upwards and inwards to the outer side of the scaphoid bone.

The inferior calcaneo-scaphoid is a broad strong band passing from the anterior and inner end of the sustentaculum tali of the os calcis to the hollow on the under surface of the scaphoid bone. It supports the head of the astragalus, and its plantar surface is in contact with the tendon of the tibialis posticus.

_ Articulation between the astragalus and scaphoid. The only ligament is

The superior astragalo-scaphoid, passing from the neck of the astragalus to the upper surface of the scaphoid bone.

Articulations between the Scaphoid, Cuboid, and Three Cuneiform Bones are connected by the following ligaments :

Dorsal ligaments, which pass from one bone to the other.

Plantar ligaments, similarly arranged upon the sole.

Interosseous ligaments (4), strong fibres passing between the rough non-articulating surfaces of the bones.

Articulation between Calcaneum and Cuboid.

The superior calcaneo-cuboid ligament passes between the dorsal surfaces of the os calcis and cuboid bones.

The internal calcaneo-cuboid or interosseous ligament attached to a deep groove on the os calcis between it and the astragalus, here blending with the superior calcaneo-scaphoid ligament, and passing to the inner side of the cuboid bone.

The Inferior ligaments are two : —

The long calcaneo-cuboid (long plantar) ligament, attached

2—2

20 THE POCKET ANATOMY

to the under surface of the os calcis in front of the tuberosities ; it passes to the posterior margin of the peroneal groove of the cuboid ; some of the fibres arch over the sheath of the tendon, and are attached to the bases of the and, 3rd and 4th meta- tarsal bones.

The short calcaneo-cuboid ligament is more deeply placed , it reaches from the tubercle and depression on the under surface of the os calcis to the under surface of the cuboid behind the peroneal groove.

VI . — T ARSO-METATARSAL ARTICULATIONS.

The metatarsal bones are connected to the tarsus by : —

Dorsal ligaments, one to each metatarsal bone from the tarsal bone it articulates with. The 2nd metatarsal has a slip from each cuneiform bone.

The plantar ligaments, disposed irregularly.

The interosseous ligaments, strong bands, three in number. The internal one passes from internal cuneiform to the 2nd metatarsal. The middle one passes between the external cuneiform and the 2nd metatarsal. The external connects the external cuneiform and the 3rd metatarsal.

The synovial membranes of the tarsus and metatarsus are six in number : —

One for the posterior calcaneo-astragaloid articulation.

One for the anterior calcaneo-astragaloid articulation and the scapho-astragaloid articulation.

One for the calcaneo-cuboid articulation.

One for the articulations of the scaphoid, and the three cuneiform bones ; the cuneiform bones with each other ; the external cuneiform and the cuboid ; and the middle and external cuneiform bones with the bases of the 2nd and 3rd metatarsal bones.

One between ist metatarsal and internal cuneiform.

One for 4th and sth metatarsal with cuboid.

VII. — ARTICULATIONS OF THE METATARSAL BONES WITH EACH OTHER.

The bases of the metatarsal bones are connected by dorsal, plantar, and interosseous ligaments.

The digital ends are united by the transverse metatarsal liga- ment, which on the plantar aspect connects the ist metatarsal with the others (compare with hand).

VIII. — METATARSO-PHALANGEAL ARTICULATIONS.

These articulations are precisely similar to the correspond- ing parts of the hand.

MUSCLES 21

IX. — ARTICULATIONS OF THE PHALANGES.

The preceding remark equally applies to these articula- tions.

THE MUSCLES.

Explanation.

The — dash divides the origin from the insertion.

Nervous supply is indicated by ( ) brackets.

Action of muscle is indicated by [ ] brackets, and if a muscle has two points on which it acts, A applies to action from origin on point of insertion, and B applies to action from insertion on point of origin.

F signifies that the attachment is fleshy.

T ,, ,, tendinous.

A ,, ,, aponeurotic.

A combination of any of these attachments may occur.

MUSCLES AND FASCLE OF THE HEAD AND

NECK.

The superficial fascia in the epicranial region and on the face is closely united to the skin, slightly developed, except between bellies of occipito-frontalis muscle. At the back part it becomes continuous with superficial fascia of posterior muscles of the neck, and descends laterally over the temporal fascia, where it envelops the external muscles of auricle, and the superficial temporal vessels and nerves. In the neck it is loose and fatty, as over rest of body.

EPICRANIAL REGION.

Occipito-frontalis : Frontal part. Has no bony attach- ments, blends with orbicularis palpebrarum, pyramidalis nasi and corrugator supercilii(p) — epicranial aponeurosis(A) (Facial). Occipital part. Outer § superior curved occi- pital lines, mastoid processes(FT) — epicranial aponeurosis, which is attached behind to curved line between fleshy heads(A). (Posterior auricular branch of facial.) [Frontal part wrinkles forehead horizontally. Occipital part removes the wrinkles; acting alternately the two parts move scalp.]

Epicranial aponeurosis unites frontal and occipital muscles,

22 THE POCKET ANATOMY

and is also attached to inner £ of superior curved line of occipital behind. Laterally it is lost over temporal fascia, where it gives origin to attrahens and attollens aurem.

AURICULAR REGION.

Attrahens aurem : fore part of epicranial aponeurosis(F) — fore part of helix, and eminence on back of pinna, corre- sponding to the fossa of the antihelix(x) (Temporal branch of facial). [Very little ; draws ear forward.]

Attollens aurem: epicranial aponeurosis(p) — cranial surface pinna, corresponding to fossa of antihelix(T) (Temporal branch of facial). [Very little ; raises ears.]

Eetrahens aurem: root of mastoid process(A)— lower part of cranial surface of concha(A) (Posterior auricular). [Very little ; draws ear back.]

PALPEBRAL REGION.

Orbicularis palpebrarum : Sphincter of eyelids. Orbital part. Internal angular process of frontal, internal tarsal ligament, nasal process of superior maxilla(F). Palp ebral part. Internal tarsal ligament(F) — external tarsal ligament(F) (Facial). Ciliary part. Marginal portion of preceding ; lies along bases of eye- lashes. [Closes eye ; maintains apposition of eyelids to eyeball.]

Tensor tarsi (Horner's muscle) : ridge of os lachrymalis(F) —joins with ciliary part of orbicularis internal to the punctum(p) (Facial). [Acting with orbicularis empties lach. rymal sac.]

Internal tarsal ligament (tendo oculi) is attached to ridge on nasal process of superior maxilla in front of lachrymal groove, divides into two slips, each joining the inner end of the corresponding tarsal cartilage.

External tarsal ligament, connects the tarsal cartilages to outer part of orbit.

Corrugator supercilii : inner part of superciliary ridge of frontal(F) — under surface of orbicularis, opposite middle of orbital arch(p) (Facial). [Wrinkles forehead vertically.]

ORBITAL REGION.

Levator palpebrse superioris : inferior surface of small wing of sphenoid, anterior to foramen opticum and external to superior oblique(x) — anterior part of superior tarsal plate, also superiorly to join orbicularis and inferiorly to superior

MUSCLES 23

fornix of conjunctiva(A) (Upper division of 3rd). [Raises upper eyelid.] The four recti arise from two common tendons — superior and inferior. Superior common tendon (ligament of Lock wood) rises above and outside optic foramen and gives origin to superior, internal and external recti (upper head). The inferior common tendon (ligament of Zinn) below and outside optic foramen goes to inferior, internal, and lower head of external recti.

Rectus superior : upper margin of optic foramen(T) — sclerotic(x) (Upper division of 3rd). [Rotates cornea up- wards and inwards.]

Rectus inferior : margin of optic foramen(T) — sclerotic(x) (Lower division of 3rd). [Rotates cornea downwards and inwards.]

Rectus interims : optic foramen(x) — sclerotic(T) (Lower division of 3rd). [Rotates cornea inwards].

Rectus externus: Upper head. Optic foramen(T). Lower head. Optic foramen and process of bone at the lower margin of spheroidal fissure(x) — sclerotic(x) (6th). [Rotates cornea outwards.] Between the two heads pass ^rd, 6th, nasal branch oj 5/A nerve and ophthalmic vein.

Obliquus superior : inner part of optic foramen(x)— passes through "pulley," thence reflected backwards and outwards between superior rectus and eyeball to be attached to scle- rotic between superior and external recti (x) (4th). [Rotates cornea downwards and outwards.] The qth nerve enters its •upper surface.

Obliquus inferior : depression on orbital plate of superior maxilla(F)— external surface of sclerotic under cover of external rectus(x). (Lower division of 3rd). [Rotates cornea upwards and outwards.] Passes outivards from origin beneath inferior rectus and between eyeball and external rectus to its in- sertion.

NASAL REGION.

Pyramidalisnasi : occipito-frontalis(F) — compressor naris(A) (Facial). [Wrinkles skin over nose.]

Compressor naris : facial surface of superior maxilla by side of anterior nares(p)— its fellow of side(A) (Facial). [Closes anterior nares.]

Levator labii superioris alseque nasi : root of nasal process of superior maxilla(F) — ist slip, cartilage of ala ; 2nd slip, orbicularis oris(p) (Facial). [Raises ala of nose and upper lip.]

Depressor al» nasi : incisor fossa of superior maxilla(F)— septum and ala of nose(p) (Facial). [Very little ; depresses ala.]

24 THE POCKET ANATOMY

Dilatator naris: Anterior slip. Cartilage of ala(p) — inner

border of integument of ala(p). Posterior slip. Nasal notch of superior maxilla(F) — inner border of integument of ala(F) (Facial). [Dilates anterior nares.]

SUPERIOR MAXILLARY REGION.

Levator labii superioris : superior maxilla and malar above infra-orbital foramen (F) — orbicularis oris(F) (Facial). [Raises upper lip.]

Levator anguli oris: canine fossa of superior maxilla, beneath infra-orbital foramen(p) — angle of mouth(p) (Facial). [Raises angle of mouth, as in smiling.]

Zygomaticus major: malar bone in front of zygoma(p) — angle of mouth(F) (Facial). [Raises angle of mouth.]

Zygomaticus minor : malar bone near maxillary suture(p) —angle of mouth(p) (Facial). [Raises angle of mouth.]

INFERIOR MAXILLARY REGION.

Levator labii inferioris, vel levator menti : incisor fossa of inferior maxilla(F) — integument of chin(p) (Facial). [Raises skin of chin.]

Depressor labii inferioris, vel quadratus menti : external oblique line of inferior maxilla from symphysis to mental foramen(p) — orbicularis oris(p) (Facial). [Draws down lower lip, everting it.]

Depressor anguli oris, vel triangularis menti : external oblique line of inferior maxilla(p) — angle of mouth (F) (Facial). [Depresses angle of mouth, as in crying.]

INTER-MAXILLARY REGION.

Orbicularis oris : sphincter of mouth. The labial part is free from attachment to bone, and forms red part of lips. The outer or facial part is connected with the muscles which converge to the angles of the mouth, and is attached in the upper lip to septum nasi and incisive fossa of superior maxilla, and in the lower lip to canine fossa of inferior maxilla(p) (Facial). [Closes oral fissure, producing radiating wrinkles.]

Buccinator: external surfaces of alveolar processes of superior and inferior maxillae, as far forwards as ist molar ; pterygo-maxillary ligament(p) — angle of mouth where fibres decussate(p) (Facial). [Closes mouth, also prevents food col- lecting between teeth and lips ; maintains tone of cheeks, as in whistling.

MUSCLES 25

The pterygo-maxillary ligament extends from the hamular process to the posterior edge of the mylo-hyoid ridge of inferior maxilla. It separates buccinator from superior con- strictor of pharynx, giving origin to both.

Risorius : fascia covering masseter(F) — apex of depressor anguli oris(F) (Facial). [Draws angle of mouth back.] (This muscle is part of the platysma of neck.)

TEMPORO-MAXILLARY REGION.

Masseter : Superficial part. Malar process of superior maxilla. Anterior § of lower border of zygoma(TA) — angle and lower £ of outer surface of ramus(p). Deep part. Posterior £ lower border and inner surface of zygoma (F) — upper £ of ramus and outer surface of coronoid process(p) (Inferior maxillary). [Muscle of mastication; elevates lower jaw and draws it forward.]

The masseteric fascia, a continuation of the deep cervical fascia, is attached above to the zygoma; continuing back- wards it invests parotid gland (parotid fascia), from the deep surface of which the stylo-maxillary ligament proceeds.

Temporal: temporal fascia and fossa(F) — internal surface and fore part of coronoid process of inferior maxilla as far as last molar(AT) (Inferior maxillary). [Muscle of mastication, closing mouth ; anterior fibres protrude jaw, posterior retract.]

The temporal fascia is attached above to the temporal ridge, and divides below into two layers, which are attached to inner and outer edges of superior border of zygoma. It covers the temporal muscle, and between the two layers are the temporal branch of temporo-malar nerve, and the orbital branch of superficial temporal artery.

PTERYGO-MAXILLARY REGION.

External pterygoid : pterygoid ridge and surface below on great wing of sphenoid, outer surface of external pterygoid plate(r) — pterygoid depression in front of neck of inferior maxilla and inter-articular fibro-cartilage of temporo-maxillary joint(p) (Inferior maxillary). [Muscle of mastication ; both acting together protrude lower jaw : acting alternately cause grinding movements, each moving jaw to opposite side.]

Between sphenoidal and pterygoid attachments, the internal maxillary artery dips down to reach spheno-maxillary fossa, and the buccal and anterior deep temporal nerves appear.

Internal pterygoid : inner surface of external pterygoid plate, tuberosity of palate bone, and tuberosity of superior

26 THE POCKET ANATOMY

maxilla(F) — angle and inner surface of ramus of inferior maxilla(TA) (Inferior maxillary). [Muscle of mastication; elevates and draws lower jaw forward.]

On muscle are inferior dental and gustatory nerves, internal maxillary and inferior dental arteries, and internal lateral ligament of jaw.

SUPERFICIAL CERVICAL REGION.

Platysma myoides : clavicle and acromion, fascia covering deltoid, pectoralis major, and trapezius(p) — Inner fibres. Blend with opposite platysma. Outer fibres. — Lower jaw, prolonged to angle of mouth and cheek(p) (Facial). [Feeble depressor of jaw ; moves skin of neck and maintains its contour.] The higher fibres of this muscle form the risorius.

Sterno-cleido-mastoid : Inner head. Upper and anterior part of ist piece of sternum(T). Outer head. Inner ^ of superior surface clavicle(F)— external surface of mastoid pro- cess from base to apex(i), and outer § of superior curved line of the occiput(A) (Spinal accessory, Deep branch of 2nd cervical). [(A) Each side acting alone rotates face to opposite shoulder and bends neck to same side ; (B) raises clavicle, and so aids forced inspiration.]

Forms anterior boundary of posterior, and posterior boundary of anterior triangles of neck. Clavicular origin conceals : anterior scalenus, omo-hyoid. Sternal origin conceals: depressors of hyoid bone, cervical lymphatic glands, great cervical vessels and pneumogastric nerve. Union of two heads conceals : middle scalenus, levator anguli scapulas, cervical plexus. Near in- sertion conceals : splenius, trachelo-mastoid, digastric, occipital artery, part of parotid.

The deep cervical fascia is attached behind to the superior curved line of the occiput, to the ligamentum nuchae and to the spine of yth cervical vertebra.

It passes forwards enclosing the trapezius, and then over the posterior triangle as a single layer (where external jugular vein pierces it) until it reaches the posterior border of the sterno-mastoid, where it divides into two layers to enclose that muscle : in this area it is attached below to the clavicle At the anterior border of the sterno-mastoid the two layers again blend together (except for about one inch above the sternum), and passing forwards, over the anterior triangle, it blends with the fascia of opposite side in the middle line.

Below where the two layers do not blend together, tbe anterior one is attached to the front of the upper part

MUSCLES 27

of the sternum and to the interclavicular ligament, whilst the posterior one is connected to the posterior edge of the upper part of the same bone. A small interval (Burn's space) is thus left, triangular in vertical section with the base at upper border of the sternum, which contains some loose areolar tissue, some fat, and often a lymphatic gland, with the anterior jugular veins.

Superiorly this anterior layer passes over the parotid and masseter, forming the parotid, and masseteric fascia, and is attached above and behind to the lower border of the zygoma, and below and in front to the lower edge of the body of the lower jaw.

From the posterior surface of the fascia covering the anterior triangle a septum passes inwards, separating the submaxillary and parotid glands, and forms the stylo- maxillary ligament.

Processes given off from the deep cervical fascia.

From the layer passing behind the sterno-mastoid there proceed : —

1. A layer which passes behind carotid vessels.

2. A layer which passes in front of carotid vessels. These two layers blend together at the inner border of the

carotid artery, forming the carotid sheath to enclose carotid artery, internal jugular, and pneumogastric nerve. The united layers pass upwards and inwards in front of the longns colli and behind the pharynx and O3sophagus, to blend with like process from opposite side and form the prevertebral fascia.

This layer separates the prevertebral muscles from the pharyngeal fascia on the pharynx and oasophagus (retro- pharyngeal space continuous with the posterior mediastinum) and is prolonged laterally over the scaleni, brachial plexus, and subclavian vessels to help form the axillary sheath.

The cervical fascia is attached in the middle line to the symphysis menti, the hyoid bone, and the anterior edge of the upper border of the sternum.

3. A layer in front of thyroid body and trachea, but behind the sterno-hyoid and thyroid muscles, which joins with a corresponding process of the opposite side, and passing down to the root of the neck in front of the trachea and large vessels, blends with the fibrous layer of the pericardium.

4. A process to enclose the omo-hyoid tendon, which binds it down to the clavicle and first rib, blending with the costo- coracoid membrane.

28 THE POCKET ANATOMY

INFRA-HYOID REGION.

Sterno-hyoid : posterior surface of sternum, clavicle and intervening ligament (F) — lower border of body of hyoid bone (A) (ist, 2nd and 3rd cervical through ansa hypoglossi). [Depresses hyoid bone.]

Sterno-thyroid : posterior surface of sternum, cartilage of ist rib(F)— oblique line on side of thyroid cartilage(p) (ist, 2nd and 3rd cervical through ansa hypoglossi). [Depresses thyroid cartilage.]

Thyro-hyoid : oblique line on side of thyroid cartilage(p) — internal half of greater cornu and outer part of body of hyoid bone(p) (ist and 2nd cervical). [Depresses hyoid on thyroid.]

Omo-hyoid: upper border of scapula behind notch, and transverse ligament(A) — lower part of body of hyoid bonefp) (ist, 2nd and 3rd cervical through ansa hypoglossi). [A de- presses hyoid, B very feebly raises shoulder.]

Consists of two bellies united by an intervening tendon. The tendon and posterior belly is bound down to clavicle and cartilage of ist rib by a process of deep cervical fascia.

SUPRA-HYO1D REGION.

Digastric : Posterior belly. Groove on internal surface of mastoid process(p). Anterior belly. Posterior surface of in- ferior maxilla, by side of symphysis(p) — intervening tendon (T), which is bound down to hyoid bone by process of deep cervical fascia (anterior, Mylo-hyoid of inferior dental ; posterior, Facial). [With posterior belly fixed and hyoid bone depressed, it depresses mandible; with the lower jaw fixed, it raises hyoid.]

Stylo-hyoid : posterior aspect of styloid process near root(x) —body of hyoid bone at union of great cornu and body(x) (Facial) . [Raises and draws back hyoid bone, and so tongue.] Perforated by tendon of digastric.

Mylo-hyoid : mylo-hyoid ridge on inner surface of inferior maxilla(F) — middle of body of hyoid bone(T), and joins fellow in median line(A) (Mylo-hyoid of inferior dental). [A raises and draws forwards hyoid under mandible ; B depresses jaw.]

Parts beneath the mylo-hyoid: sublingual and part of sub- maxillary gland, with Wharton's duct; genio-hyoid, genio- hyo-glossus, hyo-glossus, stylo-glossus muscles, sublingual and ranine arteries ; gustatory, and hypoglossal nerves ; sub- maxillary ganglion .

MUSCLES 29

Genio-hyoid : inferior genial tubercle on posterior surface of inferior maxilla near symphysis(T) — middle of body of hyoid bone(p) (ist and 2nd cervical). [Raises and draws forward hyoid.]

LINGUAL REGION.

Genio-hyo-glossus : superior genial tubercle on posterior surface of inferior maxilla near symphysis(T) — body of hyoid bone(p) (posterior fibres) : inferior surface of tongue from root to tip(p) (anterior fibres) (Hypoglossal). [Raises tongue and hyoid bone, draws tongue forwards and protrudes it to opposite side.]

Hyo-glossus : side of body, from all great cornu of hyoid and from smaller cornu(p) — back and side of tongue(p) (Hypo- glossal). [Depresses sides of tongue, making surface convex laterally.]

Parts beneath hyo-glossus : inferior lingualis, genio-hyo-glossKS and middle constrictor muscles, lingual vessels, stylo-hyoid ligament, glosso-pharyngeal nerve.

Stylo-glossus : external surface of apex of styloid process and stylo-maxillary ligament (A) — dorsum and tip of tongue(p) (Hypoglossal). [Draws tongue upwards and backwards, makes Miperior surface concave laterally.]

PHARYNGEAL REGION.

Inferior constrictor : side of cricoid cartilage ; oblique line on thyroid and surface behind it, inferior cornu of thyroid cartilage(p) — fibrous raphe in posterior median line of pharynx(p) (Pharyngeal plexus, External laryngeal, Re- current laryngeal). [Squeezes food towards oesophagus in swallowing. 3

Middle constrictor : great and small cornua of hyoid bone, stylo-hyoid ligament (F) — fibrous raphe in posterior median line of pharynx(p) (Pharyngeal plexus). [Squeezes food towards oesophagus in swallowing.] Superior laryngeal vessels and internal laryngeal nerve pass between this muscle and the inferior, near origin.

Superior constrictor : lower 3rd of posterior margin of in- ternal pterygoid plate, hamular process, pterygo-maxillary ligament, posterior part of mylo-hyoid ridge of inferior maxilla, mucous membrane of mouth and side of tongue(F) — fibrous raphe in posterior median line of pharynx(p), and pharyngeal spine on basilar process(p) (Pharyngeal plexus). [Squeezes food towards oesophagus in swallowing.] Internal

30 THE POCKET ANATOMY

carotid artery, pneumogastric and sympathetic nerves, middle con- stricter and stylo-pharyngeus, etc., lie on outer surface.

Stylo-pharyngeus : inner surface of base of styloid pro- cess^)— pharynx and posterior border of thyroid carti- lage^) (Glosso-pharyngeal). [Raises pharynx over food in swallowing.] Passes between external and internal carotid arteries.

PALATAL REGION.

Levator palati sunder surface of apex of petrous portion of temporal, lower margin of cartilage of Eustachian tube(T) — middle line of soft palate(p) (Pharyngeal plexus). [Raises palate, shutting off naso-pharynx.]

Tensor vel circumflexus palati : scaphoid fossa of sphenoid, outer side of Eustachian tube, spine of sphenoid(F) (turns round hamular process] — posterior border of hard palate, aponeurosis of soft palate(A) (Otic ganglion). [Raises and makes tense soft palate.]

Azygos uvulae : posterior nasal spine of palate bone(p) — tip of uvula(F) (Pharyngeal plexus). [Shortens uvula.]

Palato-glossus (anterior pillar of soft palate] : side and dorsum of tongue (F)— anterior and lateral surface of soft palate(p) (Pharyngeal plexus). [Tends to approximate back of tongue and soft palate.]

Palatp-pharyngeus (posterior pillar of soft palate] : Anterior fibres join opposite muscle at middle line lying between the levator and tensor. Posterior fibres join opposite fellow at middle line(p) (Pharyngeal plexus). Salpingo-pharyngeus : lower edge of cartilage of Eustachian tube — posterior border of thyroid cartilage, side of pharynx(p). [A raises pharynx ; B will, with palato-glossus, shut off mouth from naso- pharynx.]

INTRA-LARYNGEAL REGION.

Crico-thyroideus : lower cornu and lower border of thyroid cartilage(p)— front and side of cricoid cartilage(p) (External laryngeal). [Rotates posterior part of cricoid downwards and backwards, and so makes vocal cords tense.]

Thyro-arytenoideus : lower half of receding angle of thyroid cartilage, crico-thyroid membrane(p). — Two sets of fibres. Internal, edge of vocal process(F)— External, outer surface of arytenoid cartilage(p) (Recurrent laryngeal). [Slackens vocal cords.]

MUSCLES 31

Crico-arytenoideus lateralis: side of superior border of cricoid cartilage(F) — projection at external angle of base of arytenoid cartilage, and contiguous external surface(p) (Re- current laryngeal j. [Adducts cords.]

Cricp - arytenoideus posticus : depression near ridge on posterior surface of cricoid cartilage(p) — projection at external angle of base of arytenoid cartilage(p) (Recurrent laryngeal). [Abducts cords.]

Arytenoideus : single muscle in the median line, fills up posterior concave surface of arytenoid cartilages. Superficial fibres pass from apex of one cartilage to base of other. Deep fibres pass between posterior surfaces of the cartilages (Re- current laryngeal). [Approximates cords.]

ANTERIOR VERTEBRAL REGION.

Rectus capitis anticus major: four tendinous slips from anterior tubercles of transverse processes of 6th, 5th, 4th, 3rd cervical vertebrae(T) — basilar process of occipital(p) (ist, 2nd. 3rd and 4th cervical). [Flexes head and cervical spine.]

Rectus capitis anticu?j minor: root of transverse process and lateral mass of atlas(p) — basilar process of occipital(p) (ist cervical). [Flexes head.]

Rectus lateralis : superior surface of transverse process of atlas(F)— jugular process of occipital(p) (ist cervical). [Flexes head to same side.] Highest intertransverse muscle.

Longus colli : Superior oblique part. Anterior tubercles of transverse processes of 3rd, 4th, 5th cervical vertebrae(T) — tubercle on anterior arch of atlas(T). Inferior oblique part. Bodies of first three dorsal(p)— anterior tubercles of trans- verse processes of 5th and 6th cervical(T). Vertical part. Bodies of lower two cervical and upper three dorsal and itranverse processes of 4th, 5th, 6th, 7th cervical vertebrae(FT) — bodies of and, 3rd and 4th cervical vertebrae(T) (Cervical nerves). [Flexes cervical spine.]

LATERAL VERTEBRAL REGION.

Scalenus anticus : anterior tubercles of transverse pro- •cesses of 3rd, 4th, 5th, 6th cervical vertebrae(T) — scalene tubercle on inner border and superior surface of ist rib(T) — (Branches of lower cervical) . [A raises ribs as in forced inspira- tion, B flexes spine and bends neck to same side.] Phrenic nerve lies along anterior surface; subclavian artery passes behind at origin.

Scalenus medius : posterior tubercles of transverse pro- cesses of lower six cervical vertebrae(T) —rough elevation on

32 THE POCKET ANATOMY

superior border of istrib, behind groove for subclavian artery (F) (Branches of lower cervical). [A raises ribs as in forced inspiration, B flexes spine laterally.]

Scalenus posticus : posterior tubercles of transverse pro- cesses of lower two or three cervical vertebrae(x) — superior border of 2nd rib(x) (Branches of lower cervical). [A raises ribs, B flexes cervical spine laterally.]

POSTERIOR VERTEBRAL REGION.

Rectus capitis posticus major : spinous process of axis(T) — outer J inferior curved line of occiput and bone below(F) (ist cervical, posterior primary division). [Extends head on spine.]

Rectus capitis posticus minor : posterior tubercle of neural arch of atlas(T) — inner part of inferior curved line of occiput and bone between this and foramen magnum(F) (ist cervical, posterior primary division). [Extends head on spine.]

Obliquus inferior : spinous process of axis(p) — transverse process of atlas(T) (ist cervical, posterior primary division). [Rotates face to same side.]

Obliquus superior : superior surface of transverse process of atlas(T) — occipital bone, between the two curved lines(p) (ist cervical, posterior primary division). [Rotates face to oppo- site side.]

MUSCLES AND FASCLE OF UPPER EXTREMITY.

ANTERIOR THORACIC REGION.

The deep fascia of the pectoral region covers the large pectoral muscle, is attached above to the clavicle, internally to the sternum, becoming continuous externally with fascia? of shoulder, axilla, and lateral thoracic region.

The costo-coracoid membrane, continuous with the deep fascia of this part, is attached above to the clavicle so as to enclose the subclavius muscle ; the posterior layer is continuous with the axillary sheath derived from the deep cervical fascia. The lower edge (costo-coracoid ligament) reaches from the ist costal cartilage to the coracoid process, and passes down- wards over pectoralis minor. It is pierced by cephalic vein, acromio-thoracic vessels, and external anterior thoracic nerve.

The axillary fascia is placed across the axilla; it is derived in front from the sheaths of the pectoral muscles, and joins, at the posterior border of the axilla, the sheaths of the latis- simus dorsi and teres major.

MUSCLES 33

Pectoralis major : superiorly, sternal half of clavicle(p) ; in- ternally, front of sternum, cartilages of upper six ribs(F) ; in- fer iorly aponeurosis of external oblique muscle of abdomen (F) — outer ridge of bicipital groove of humerus(T) (External and internal anterior thoracic). [A adducts humerus, flexes shoulder; B raises ribs in forced inspiration.] Anterior boundary of axilla, separated front the deltoid above by cephalic vein and branch of acromio - thoracic artery.

Pectoralis minor : 3rd, 4th, and 5th ribs outside cartilages, aponeurosis over intercostal muscles(F) — anterior* of superior surface and inner border of coracoid process of scapula(x) (Internal anterior thoracic). [Draws scapula forwards and depresses it.] Forms middle £ of anterior axillary boundary, and conceals 2nd part of axillary artery.

Subclavius : ist rib at junction of bone and cartilage(x) — groove on under surface of clavicle between the two tubercles(F) (Branch from 5th and 6th cervical). [Depresses clavicle.] Encased by costo-coracoid sheath.

LATERAL THORACIC REGION.

Serratus magnus : eight or nine digitations from as many ribs, the ist digitation being attached to ist and 2nd ribs; aponeurosis over intercostal muscles ; lower four slips digitate with external oblique muscle of abdomen(F) — vertebral border of ventral surface of scapula; viz., ist digitation from ist and 2nd ribs to upper angle, from 2nd and 3rd ribs to base ; the rest to inferior angle(p) (Posterior thoracic). [Draws scapula forwards, and by rotating inferior angle forwards and upwards, raises arm.]

ACROMIAL REGION.

The deep fascia over the shoulder conceals the back part of the deltoid and the infra-spinatus muscle, and is attached to the clavicle, acromion, and spine of scapula.

Deltoid : outer £ anterior border of clavicle, anterior edge of acromion, all lower edge of spine of scapula(F) — rough deltoid impression on outer surface of humerus just above the middle(T) (Circumflex). [Abducts arm; anterior fibres flex shoulder, posterior extend.]

Parts covered by deltoid : head and neck of humerus ; bursa between head of humerus and muscle; tendons of insertion of subscapularis, pectorales major and minor, teretes naajor and minor, latissimus dorsi, supra- spinatus, infra-spinatus. Origins of coraco-brachialis, biceps (two heads), triceps (long

3

34 THE POCKET ANATOMY

and outer heads): capsular, coraco - acromial, humeral, clavicular, costo-coracoid (external part) ligaments ; coracoid process : acromio-thoracic, supra-scapular, branch of superior profunda, and circumflex vessels ; circumflex nerve.

ANTERIOR SCAPULAR REGION.

Subscapularis : all subscapular fossa, except at neck, angles, and inner border(p T A) — small tuberosity of humerus(T) and neck of humerus for one inch below(F) (Short subscapular and branch from lower subscapular). [Flexes and inwardly rotates shoulder-joint.] Bursa placed between the tendon and root of coracoid process, communicating with shoulder-joint.

POSTERIOR SCAPULAR REGION.

Supra-spinatus : supra-spinous fossa, except near neck of scapula ; upper surface of spine, and fascia covering muscle(F) — upper of three facets upon great tuberosity of humerus(T) (Supra-scapular). [Abducts humerus.]

Infra-spinatus : infra-spinous fossa, except at neck, axillary border, and inferior angle ; from inferior surface of spine of scapula, and fascia covering muscle(F)— middle of three facets on great tuberosity of humerus(T) (Suprascapular). [Extends and externally rotates shoulder-joint.]

Teres minor : from superior § of axillary border of dorsum of scapula, its investing fascia(p) — lowest of three facets upon great tuberosity of humerus(T), and bone below(p) (Circum- flex ; has a gangliform swelling on it}. [Adducts and externally rotates humerus.] Dorsal branch of subscapular artery bends backwards in front of this muscle to reach infra-spinous fossa.

Teres major : from rough surface at inferior angle of dorsum of scapula, and axillary border for lower ^, septum between it and teres minor(p) —inner edge of bicipital groove of humerus (T) (Lower subscapular). [Adducts and internally rotates humerus.] A bursa is sometimes placed between tendon and humerus posteriorly , and between ten don and latissimus dor si insertion an teriorly .

ANTERIOR HUMERAL REGION.

The deep fascia of the arm is continuous with that of the shoulder, investing the muscles of this region. It gives off on either side an intermuscular septum, which is attached to the^condyle and supra-condylar ridge.

Coraco -brachialis: apex of coracoid process of scapula, tendon of coracoid head of biceps(F) — rough ridge near middle

MUSCLES 35

of inner surface of humerus ; some of the upper fibres join a fibrous arch which is attached above to the small tuberosity(x) (Musculo-cutaneous). [Flexes and adducts shoulder-joint.] Brachial vessels to inner side.

Biceps : Long or glenoid head. From scapula at upper border of glenoid cavity, and from glenoid ligament, within the shoulder-joint(T). Short or coracoid head. Apex of coracoid process of scapula(x) — rough and hinder part of tubercle of radius(i) and fascia of forearm (Musculo-cutaneous). [Flexes shoulder, flexes elbow, supinates radius.] A bursa is placed on the smooth and fore part of tubercle. Inner border, the guide to brachial vessels below middle of humerus. A broad band, the semilunar fascia, is given off from inner side of tendon opposite the elbow-joint, covering brachial artery and joining deep fascia of fore- arm.

Brachialis anticus : lower half of outer and inner surfaces of shaft of humerus, embracing insertion of deltoid, all inner intermuscular septum, and upper part of outer intermuscular septum (F) — rough surface in front of coronoid process of ulna(T) (Musculo-cutaneous, Musculo-spiral). [Flexes elbow.] Brachial artery, median, musculo - spiral and musculo - cutaneous nerves lie on it.

POSTERIOR HUMERAL REGION.

Triceps : Long or middle head. Depression on axillary border of scapula, close beneath glenoid cavity(x). External head. From root of great tuberosity to musculo-spiral groove on posterior surface of humerus(p). Internal head. Posterior surface of shaft of humerus, by side of and below musculo- spiral groove, internal and external intermuscular septa(p) — posterior surface of olecranon process of ulna(x) (Musculo- spiral). [Extends and adducts shoulder, extends elbow.] Bursa is placed between the tip of process and tendon.

Sub-anconeus : by two fasciculi just above olecranon fossa of humerus(F) — synovial sac of elbow-joint(F) (Musculo-spiral). [Raises synovial membrane out of olecranon fossa in extension of elbow.]

OF FOREARM — ANTERIOR, (a) Superficial Layer.

The deep fascia of the forearm, continuous above with fascia of arm, is attached posteriorly to subcutaneous edge of ulna, and invests the muscles in this region.

Anterior annular ligament (v. p. 13) is continuous by its upper border with the deep fascia of the forearm.

3-2

36 THE POCKET ANATOMY

Posterior annular ligament (v. p. 13) is the thickened lower part of the posterior part of the deep fascia.

Pronotor radii teres : Humeral head. Internal supra-condylar ridge of humerus, internal condyle of humerus by common flexor tendon. Ulnar head. Inner border of coronoid process of ulna, fascia and septum (F) — rough impression about middle of outer surface of radius(x) (Median) £.7 [Flexes elbow and pronates forearm.] Median nerve enters forearm between the two heads of origin.

Flexor carpi radialis : common flexor tendon from internal condyle of humerus(T), aponeurosis of forearm, intermuscular septa(p) — bases of palmar aspect of 2nd and 3rd metacarpal bones(x) (Median)*,? [Flexes elbow and wrist, abducts hand.] External edge of muscle, guide to radial artery. Passes through groove in trapezium, and has special sheath externally under annular ligament.

Palmaris longus : common flexor tendon from internal con- dyle of humerus(x), aponeurosis of forearm(F), intermuscular septa(F) — Palmar fascia, and a slip to short muscles of thumb (T) (Median).? [Flexes wrist, makes tense palmar fascia.] Passes over annular ligament.

Flexor carpi ulnaris : Humeral head. Common flexor tendon, from internal condyle of humerus(T). Ulnar head. Inner side of olecranon, upper f of posterior border of ulna(A) — Pisiform bone and prolonged to base of 5th metacarpal and hook of Cuneiform bone(x) (Ulnar)j8,J [Flexes elbow and wrist, adducts hand.] Radial side of muscle, guide to ulnar artery. Ulnar nerve enters forearm between two heads of origin.

Flexor sublimis digitorum, vel perforatus : Humeral head. Common flexor tendon from internal condyle of humerus(x), internal lateral ligament(F), intermus^ula^sejjtaCFV Ulnar head. Inner border of coronoid processoiulna. ' Radial head. Oblique line of radius below tubercle, and part of anterior border(A) — sides of middle phalanges of ringers, tendon being split for flexor profundus digitorum(x) ( Median ).^|;/[Flexes elbow, wrist, carpal, metacarpal, and ist interphalangeal joints.] Tendons pass under annular ligament, in pairs, those of middle and ring-finger being anterior to those of index and little fingers.

(b) Deep Layer.

Flexor profundus digitorum, w/perforans : upperf of anterior and internal surfaces of shaft of ulna, upper f of ulnar half of interosseous membrane, aponeurosis from posterior border of ulna(p) — palmar surfaces of bases of last phalanges(xj. (Inner

MUSCLES 37

half, Ulnar ; Outer half, Anterior interosseous of median.) [Flexes wrist, metacarpal, phalangeal, and all interphalangeal joints.] Tendons pass beneath annular ligament.

Flexor longus pollicis : hollow on upper § of anterior sur- face of shaft of radius, outer £ of interosseous membrane for same distance(p) ; base of coronoid process of ulna by a separate slip(p) — base of last phalanx of thumb(T) (Anterior interosseous)^ ) [Flexes wrist and all joints of thumb.] Tendon passes beneath the annular ligament.

Pronator quadratus : anterior surface and anterior border of shaft of ulna, for lower fourth(p) — for two inches into lower end of anterior surface and anterior border of radius(p) (Anterior interosseous).^ /[Pronates radius.]

POSTERIOR, (a) Superficial layer.

Supinator longus : upper § external supra-condylar ridge ofhumerus, external intermuscular septum(p) — root of styloid process of radius(x) (Musculo-spiral). [Flexes elbow and pronates or supinates radius from extreme position to midway between pronation and supination.]

Extensor carpi radialis longior : lower £ of external supra- condylar ridge of humerus, external intermuscular septum(p) — base of posterior surface of 2nd raetacarpal(x) (Musculo- spiral). [Extends elbow, extends and abducts hand.] Passes in groove, posterior to styloid process of radius.

Extensor carpi radialis brevior : common extensor tendon from external condyle of humerus(x), external lateral ligament, intermuscular septum (F) — base of posterior surface of 3rd metacarpal(x) (Posterior interosseous). [Extends elbow and wrist, abducts hand.]

Extensor communis digitorum : common extensor tendon from external condyle of humerus(x) ; intermuscular septum(F) — dorsa of last two phalanges of fingers(x) (Posterior in- terosseous). [Extends wrists and all joints of carpus and fingers.] The four tendons pass through a separate compartment of the posterior annular ligament with the extensor indicts. The tendons of the middle, ring, and little finger are connected by tendinous slips.

Extensor minimi digiti : common extensor tendon from external condyle of humerus, deep fascia and intermuscular septum(x) — 2nd and 3rd phalanges of little finger joining common expansion(x) (Posterior interrosseous). [Extends wrist and all joints of little finger.] Tendon passes through separate sheath of posterior annular ligament, below which it splits into two, the external one being united by a cross-piece with the tendon of common extensor going to little finger.

38 THE POCKET ANATOMY

Extensor carpi ulnaris: common extensor tendon from external condyle of humerus(T), intermuscular septum (F) by aponeurosis from upper § of posterior border of ulna(A) — prominence on ulnar side of base of 5th metacarpal bone (T) (Posterior interosseous). [Extends wrist, carpal joints and 5th metacarpo-phalangeal joint, adducts hand.] Has separate sheath in posterior annular ligament.

Anconeus : posterior surface of external condyle of humerus (T) and deep fascia(F) — outer side of olecranon, impression on upper J of posterior surface of ulna limited by oblique line(p) (Musculo-spiral). [Extends elbow.] The recurrent interosseous vessels lie beneath this muscle.

(b) Deep Layer.

Supinator brevis : external condyle, external lateraf liga- ment of elbow-joint, orbicular ligament of radius, depression below lesser sigmoid cavity, external edge of ulna for 2 inches (F) — surrounds upper £ of radius, is attached to all the neck, except at inner side, to the upper £ of posterior, and upper £ of external surfaces(F) (Posterior interosseous). [Extends elbow, supinates radius.]

Extensor ossis metacarpi ppllicis : middle £ of posterior surface of shaft of radius, special impression on superior and external part of posterior surface of ulna for same length, intervening interosseous membrane(F) — dorsal aspect of base of ist metacarpal (Posterior interosseous). [Extends ist carpo-metacarpal joint abducts hand.] The radial artery winds backwards beneath tendon near carpus.

Extensor brevis pollicis : posterior surface of radius and interosseous membrane below preceding muscle for about i£ inches(F)— dorsal aspect of base of ist phalanx of thumb (T) (Posterior interosseous). [As preceding ; also extends ist metacarpo-phalangeal joint ] Goes through groove under posterior annular ligament with extensor ossis metacarpi pollicis.

Extensor longus pollicis : posterior surface of ulna, on inner side and below extensor ossis metacarpi pollicis for 4 inches, interosseous membrane(F) — dorsal aspect of base of last phalanx of thumb(x) (Posterior interosseous). [Ex- tends wrist and all joints of thumb.] Tendon goes through separate sheath of posterior annular ligament, and below is separated from other extensors of thumb by a triangular interval, which con- tains the radial artery.

Extensor indicis : internal part of posterior surface of shaft of ulna for about 3 inches just below middle, and interosseous

MUSCLES 39

membrane(p) — joins tendon of extensor communis digitorum to 2nd and 3rd phalanges of index-finger(x) (Posterior inter- osseous). [Extends wrist and all joints of index.]

THUMB, THENAR EMINENCE.

Abductor pollicis : ridge of trapezium, sometimes scaphoid, upner part of annular ligament(p) — outer side of base of ist phalanx of thumb(x) (Median). [Abducts thumb.]

Opponens pollicis : anterior surface and ridge of trapezium, annular ligament(p) — whole length of radial border of shaft of ist metacarpal(F) ("Median). [Opposes thumb to palm.]

Flexor brevis pollicis : Outer head. Lower border of annular ligament — outer margin of the base of ist phalanx of thumb (Median). Inner head. Inner side of base of tst metacarpal bone— inner side of base of ist phalanx of thumb (Ulnar). [Flexes metacarpo-phalangeal and ist interphalangeal joint of thumb.] A sesamoid bone developed in each tendon of insertion. Deep palmar arch of radial, issues from behind inner head.

Adductor obliquus pollicis : sheath of flexor carpi radialis, anterior carpal ligaments, os magnum, bases of 2nd and 3rd metacarpal bones — inner side of base of ist phalanx of thumb (Ulnar). [Adducts and flexes thumb.]

Adductor transversus pollicis : ridge on lower § of anterior surface of shaft of 3rd metacarpal(p) — ulnar side of base of ist phalanx of thumb(x) (Ulnar). [Adducts and flexes thumb.]

LITTLE FINGER, HYPOTHENAR EMINENCE.

Palmaris brevis : annular ligament, palmar fascia(p) — skin on ulnar side of palm(p) (Ulnar). [Corrugates skin on ulnar side of palm.]

Opponens minimi digiti : process of unciform bone, lower part of annular ligament(p)— ulnar edge of 5th metacarpal(F) ( Ulnar). [Opposes little finger to palm.]

Flexor brevis minimi digiti : tip of process of unciform, annular ligament(p) — ulnar side of base of ist phalanx of little finger(T) (Ulnar). [Flexes little finger.]

Abductor minimi digiti : pisiform bone, tendon of flexor carpi ulnaris(p) — ulnar side of base of ist phalanx of little finger(T) (Ulnar). [Abducts little finger.]

DEEP PALMAR REGION.

Lumbricales (4) : radial side of deep flexor tendons (2 inner from ulnar margins of and and 3rd tendons also) (K) — radial

40 THE POCKET ANATOMY

side of tendinous expansion on dorsa of ist phalanges of fingers(r) (2 outer median, 2 inner ulnar). [Flex metacarpo- phalangeal and extend interphalangeal joints.]

Interossei dorsales (4) : ist muscle (abductor indicts). Outer head. From upper ^ of ulnar border of ist metacarpal(F). Inner head. Radial border of 2nd metacarpal(F). The others from posterior part of lateral surfaces of both metacarpals, between which they lie — ist and 2nd muscles to radial side of ist phalanx of index and middle fingers respectively, 3rd and 4th in similar manner to ulnar side of middle and ring fingers (T). Each is inserted partly into base of ist phalanx, and partly into expansion of common extensor on ist phalanx(x) (Ulnar). [Abduct fingers from middle line of hand — i.e., 3rd (middle) finger ; also same action as lumbricales.]

Interossei palmares (3) : ist from ulnar side of 2nd meta- carpal, 2nd and 3rd from radial sides of 4th and 5th meta- carpals respectively (F) — ist phalanx of finger from which they arise and on the same side as the origin, and into extensor tendon expansion(x) (Ulnar). [Adduct fingers towards middle line, and same action as lumbricales.]

MUSCLES AND FASCIA OF BODY.

BACK, IST LAYER.

Trapezius : spinous processes of all dorsal and 7th cervical vertebrae, with supra-spinous ligaments, ligamentum nuchas, inner Jrd of superior curved line of occiput(T) — outer £rd of posterior border of clavicle, superior edge of acromion, superior lip of posterior border of spine of scapula(F), and rough im- pression on spine about i inch from root(T) (Spinal accessory, 3rd and 4th cervical by cervical plexus.) [A — Upper fibres draw scapula and clavicle upwards, lower fibres downwards, all backwards ; B pulls head backwards, and also flexes to same side.] Anterior margin forms posterior boundary of posterior triangle of neck.

Latissimus dorsi: spinous processes of lower 6 dorsal, supra-spinous ligaments(A) ; from the posterior layer of the lumbar aponeurosis, by which it is attached to all the lumbar and sacral spines, and posterior £ of outer edge of iliac crest, beyond this for i inch(p), lower 3 or 4 ribs(F), and occasionally a slip from angle of scapula — bottom of bicipital groove of humerus(x) (Long subscapular). [Draws arm down and back- wards, rotating inwards.] In the back the latissimus is posterior to

MUSCLES 4»

the teres major, but twisting upon itself it is inserted anteriorly to teres, and lowest fibres are inserted highest.

BACK, 2ND LAYER.

Levator anguli scapulae : posterior tubercles of transverse processes of upper three or four cervical vertebrae (T) — verte- bral border of scapula between spine and superior angle (F) (5th cervical [nerve to rhomboidei] and deep branches from 3rd and 4th cervical). [Elevates scapula.] Forms part oj floor of posterior triangle of neck.

Rhomboideus minor : ligamentum nuchae, spinous processes of yth cervical and ist dorsal vertebrae(T) — vertebral border of scapula, opposite root of spine(p) (sth cervical). [Elevates and draws back scapula.]

Rhomboideus major : spines and supra-spinous ligaments of upper 4 or 5 dorsal vertebrae, below preceding(x)— vertebral border of scapula between spine and inferior angle (F) (5th cervical). [Elevates and draws back scapula.] Sometimes the fibres end in a tendinous arch near the bone.

BACK, 3RD LAYER.

Serratus posticus superior: ligamentum nuchae, spinous processes of yth cervical and two or three superior dorsal vertebrae, supra-spinous ligament(A)— upper borders and outer surfaces of 2nd, 3rd, 4th, and 5th ribs external to angle(p) (External posterior branches of dorsal). [Elevates upper ribs.]

Serratus posticus inferior: spinous processes of nth and 1 2th dorsal, and ist and 2nd lumbar vertebrae, and from tendon of origin of latissimus dorsi and the fascia lum- borum(A)— inferior borders of lower four ribs external to angle(p) (External posterior branches of dorsal). [Draws lower ribs downwards and backwards, fixing them for dia- phragm to act from.]

The vertebral aponeurosis. A thin membrane, attached to the spines of the dorsal vertebrae, and passing outwards to the angles of the ribs. Below it is joined to the upper edge of the inferior serratus and the tendon of latissimus, whilst above it passes beneath the superior serratus and splenius to become continuous with the deep fascia of the neck. It binds down the erector spinae in the groove between the vertebral spines and the angles of the ribs.

Splenius : lower £ of ligamentum nuchae, spinous processes of yth cervical and upper 6 dorsal vertebrae, supra-spinous

42 THE POCKET ANATOMY

ligaments(A) — Capitis, apex and hinder border of mastoid process, outer £ superior curved line of occiput(T) ; Colli, posterior tubercles of transverse processes of ist, 2nd, and 3rd cervical vertebrae (T) (External posterior branches of cer- vical). [Extends spine and head ; laterally flexes head and rotates face to the same side.]

BACK, 4TH LAYER.

Erector spinse : Outer mass. Ilio-costalis, musculus ac- cessorius, cervicalis ascendens. Inner mass. Longissimus dorsi, transversalis colli, trachelo-mastoid. [In all its parts extends spine.]

Erector spinse : posterior ith inner lip of iliac crest, from the sacral transverse processes, and lower part of posterior surface of sacrum, from the sacral, lumbar and lower 3 dorsal spines, with supra-spinous ligaments(x). Divides opposite last rib into sacro-lumbalis and longissimus dorsi (External posterior branches of sacral and lumbar).

Ilio-costalis : erector spinas(F) — angles of lower 6 or 7 ribs (T) (External posterior branches of lumbar and dorsal).

Musculus accessorius : angles of lower 6 ribs(x) — angles of upper 6 ribs, and transverse process of 7th cervical(x) (External posterior branches of dorsal).

Cervicalis ascendens : angles of 3rd, 4th, 5th, and 6th ribs (T) — Posterior transverse tubercles of 6th, 5th, and 4th cervical vertebrae(x) (External posterior branches of cervical).

Longissimus dorsi. (See erector spines, of which it forms nearly the whole of the inner mass.) — Internally. Accessory processes of lumbar and transverse processes of dorsal vertebrae(XF). Externally. Lumbar transverse processes(p), middle layer of fascia lumborum : to all the ribs except first two or three by fleshy processes between tubercle and angle(p) (External posterior branches of lumbar and dorsal).

Transversalis colli : transverse processes of upper 5 dorsal vertebrae(x) — Posterior tubercles of transverse processes of 6th, 5th, 4th, 3rd, and and cervical vertebrae (x) (External posterior branches of cervical).

Trachelo-mastoideus: transverse processes of upper 4 dorsal vertebrae(x), articular processes of 7th, 6th, 5th, and 4th cervical vertebrae (x) — posterior edge of mastoid process (F) (External posterior branches of cervical).

Spinalis dorsi : spinous processes of nth and i2th dorsal and ist and 2nd lumbar vertebras (FX) — Spinous processes of

MUSCLES 43

upper 4 or 8 dorsal vertebrae(T) (External posterior branches of dorsal and lumbar).

Complexus : transverse processes of upper 6 dorsal and yth cervical, articular processes of inferior 3 or 4 cervical, and spinous process of yth cervical vertebrae(T) — Impression between superior and inferior curved lines of occiput(F) (Suboccipital, internal posterior branches of cervical). [Ex- tends head, and rotates face to the opposite side.] The inner part of this muscle is sometimes described as a separate muscle, called biv enter cervicis.

BACK, 5TH LAYER.

Semi-spinalis dorsi : transverse processes of loth, gth, 8th, 7th, and 6th dorsal vertebrae(x) — Spinous processes of upper four dorsal and last two cervical vertebrae(T) (Internal pos- terior branches of dorsal). [Extends spine.]

Semi-spinalis colli : transverse processes of upper 6 dorsal (FT) — spinous processes of and, 3rd, 4th, and 5th cervical vertebrae(T) (Internal posterior branches of cervical). [Ex- tends spine.]

Multifidus spinse : back of sacrum as low as 4th sacral foramen; inner surface of posterior superior iliac spine, posterior sacro-iliac ligament, mammillary processes of lum- bar, transverse processes of dorsal, articular processes of lower 5 cervical vertebrae(Fx) — spines and neural arches of vertebrae from 3rd sacral to and cervical(p) (Internal posterior branches of sacral, lumbar, dorsal and cervical). [Extends spine.] Fills groove on either side of spinous processes of vertebra.

Rotatores spinse, vel dorsi (eleven in number) : tip and upper edge of transverse process of a dorsal vertebra(p) — lower border of lamina of vertebra next above (A) (Internal posterior branches of dorsal). [Rotate spine.]

Inter-spinales : placed in pairs, one on each side of inter- spinous ligament between spinous processes (Internal posterior branches of cervical, dorsal, and lumbar). [Extend spine.] These muscles are wanting between ist and 2nd cervical, and all the dorsal except first and last two pairs.

Inter - transversales : lie between transverse processes. Cervical (seven pairs, two sets). One set attached to anterior, the other to the posterior tubercles. Dorsal. Single sets, from three to six in number, attached to the processes of the lower vertebrae. Lumbar. Four in number, the lower ones filling up the spaces between processes entirely. A second set here pass between adjacent accessory processes. (Internal posterior branches of cervical, dorsal, and lumbar). [Laterally flex spine.]

44 THE POCKET ANATOMY

ABDOMINAL REGION.

Obliquus abdominis externus: eight digitations from in- ferior borders and outer surface of eight lower ribs, upper five digitating with serratus magnus, lower three with latis- simus dorsi(p) — Anterior half of external lip of iliac crest, and aponeurosis in front of belly, which is attached to pubic spine and symphysis below(A), blends above with the fascia over the pectoralis major, and joins in the middle line with the opposite aponeurosis, forming the linea alba ; the rest of the fibres forming Poupart's and Gimbernat's ligaments (A) (Lower intercostals.Ilio-hypogastric, and Ilio-inguinal). [Sup ports and compresses viscera, draws down lower ribs, and laterally flexes thorax.]

The external abdominal ring is an opening formed by a diver- gence of some of the lower fibres of the aponeurosis of the external oblique muscle ; it is situated just above the crest of the pubes, and transmits spermatic cord in male and round ligament in female. Boundaries — Below. Pubic crest. Above. Arched fibres. Laterally. External and internal pillars ; the external pillar is attached below to pubic spine, the internal pillar to pubic symphysis. The intercolumnar fascia passes between the pillars, and is prolonged downwards over the cord.

Poupart's Ligament. The part of the aponeurosis of the ex- ternal oblique extending between anterior superior iliac spine and pubic spine. The inner attachment is prolonged along the pectineal line, forming Gimbernat's ligament, of which some fibres are again reflected upwards and inwards to linea alba, forming triangular fascia.

Obliquus interims : outer £ of Poupart's ligament, anterior § middle lip of iliac crest, fascia lumborum between iliac crest and I2th rib(p) — inferior edges of cartilages of lower three ribs on posterior surface, aponeurosis blending with its fellow at linea alba; some of the lower fibres of the aponeurosis arch over spermatic cord, join tendon of transversalis just above pectineal line, forming the conjoined tendon, which is attached to pectineal line, and crest of pubes(T) (Lower inter- costals, Ilio-hypogastric). [As externus.] Aponeurosis forms sheath to encase the rectus except at lower fourth posteriorly.

Cremaster (peculiar to male) : middle of Poupart's ligament and internal oblique(p) — crest of os pubis(x) (Genito-crural). [Supports and raises testis.] Fibres embedded in fascia (cremas- teric) derived from internal oblique, covering cord and testis.

Transversalis : outer £ Poupart's ligament, anterior f inner lip iliac crest, inner surfaces of cartilages of lower six ribs(p)

MUSCLES 45

fascia lumborum(T) — lower fibres end in the conjoined tendon, inserted into pubes and pectineal line(x) ; rest of fibres ter- minate in an aponeurosis attached to linea alba(A) (Lower intercostals, Ilio-hypogastric, Ilio-inguinal) . [Supports and compresses viscera.] As low as midway between pubes and umbilicus, the aponeurosis is posterior to the rectus, but below this level it is anterior.

The Posterior aponeurosis of the Transversalis or fascia lumborum is attached to the lower border of the last rib above, and to the ilio-lumbar ligament and posterior part of the iliac crest below. Tracing it towards the spine, it splits to enclose the quadratus, and becomes attached to the lumbar transverse processes. From the posterior of these layers a process is given off to the lumbar spines, enclosing the erector spinse.

Rectus abdominis : pubic crest and symphysis(x) — ensiform appendix, cartilages of 5th, 6th, and yth ribs, bone and cartilage of 5th rib(FT) (Lower intercostals Ilio-hypogastric). [Supports viscera, flexes spine, A drawing down thorax, B drawing up pelvis, as in climbing.] Traversed by three or four tendinous intersections, linea transverse. Sheath of rectus. Aponeurosis of internal oblique splits at outer edge of muscle, one piece passing anteriorly, the other posteriorly. The posterior part is joined by aponeurosis of transversalis, and is deficient at lower fourth ; the lower free border forms the Fold of Douglas. The anterior part blends with aponeurosis of the external oblique.

Pyramidalis : front of pubes and anterior pubic ligament(x) — linea alba(x) midway between umbilicus and pubes (i2th intercostal). [Makes linea alba tense.] Enclosed in sheath of rectus, and frequently absent.

Quadratus lumborum : Anterior part. Upper edge of trans- verse processes of 3rd, 4th and 5th lumbar vertebrae — inner £ lower border 1 2th rib. Posterior part. Ilio-lumbar ligament, and inner lip of iliac crest for 2 inches external to it (A) — apices of transverse processes of upper four lumbar (T), inner £ in- ferior border of i2th rib(p) (Anterior branches of lumbar). [Flexes spine laterally, draws down last rib and with its fellow extends spine.]

THORACIC REGION.

Intercostales extern! (n): outer lip of groove on inferior border of rib, from the tubercle to costal cartilage(K) — outer -edge of superior border of rib belo W(F) (Intercostals) . [Elevate Tibs and aid inspiration.] Fibres run downwards ana forwards.

46 THE POCKET ANATOMY

The corresponding spaces between the rib cartilages are occupied by th* anterior intercostal aponeurosis.

Intercostales intern! (n) : inner lip of groove on inferior border of rib, extending from angle to sternum(F) — inner edge of superior border of rib below (Intercostals). [Probably ele- vate ribs and aid inspiration.] Fibres run downwards and back- wards, but not so obliquely as the external muscles. The inner surface of each intercostal space between the tubercle and angle is occupied by the posterior intercostal aponeurosis. The intercostal vessels and nerve lie between the external and internal muscles.

Subcostales (10) : inner surface of a rib, near angle(p) — inner surface of ist, 2nd, or 3rd ribs below(FT) (Intercostals). [Elevate ribs.]

Triangularis aterni : side of ensiform appendix and sternum, as high as 3rd intercostal space, posterior surfaces of cartilages of 7th, 6th, and 5th ribs(F)— posterior surfaces of 2nd, 3rd, 4th, 5th and 6th ribs at junction of bone and cartilage(TF) (Anterior branches of intercostals). [Draws down ribs.]

Levatores costamm (12) : apex and lower border of trans- verse processes of yth cervical and upper n dorsal vertebrse (T) — superior border of rib below, extending from tubercle to angle(F) (Intercostals). [Raise ribs.]

DIAPHRAGMATIC REGION.

Diaphragma : posterior surface of ensiform appendix, in- ternal surfaces of lower six costal cartilages(F), ligamenta arcuata (externa et interna) (A). Right crus, from bodies and intervertebral substances of ist, 2nd, 3rd lumbar vertebrae(T). Left crus, from bodies and intervertebral substances of ist and 2nd lumbar vertebrae(T) — central tendon (Phrenics). [En- larges vertical diameter of thorax, so aids inspiration.] The ligamentum arcuatum internum arches over psoas, attached to body of ist lumbar vertebra internally and to transverse pro- cess of ist lumbar vertebra externally. The ligamentum arcuatum externum reaches from transverse process of ist lumbar ver- tebra to lower border and apex of last rib, arching over quadratus.

Openings. AORTIC(F) : between the crura and spine, trans- mits aorta, thoracic duct, and vena azygos major. CESOPHA- GEAL(F) : above and little to left of aortic, transmits 0330- phagus and pneumogastric nerves. CAVAL(T) : in the right leaflet of tendon, transmits vena cava inferior, which is in- separably united to it. In each crus there is a fissure for the three splanchnic nerves, the left one transmitting in addition

MUSCLES 47

the vena azygos minor. The cord of the sympathetic per- forates the outer part of the crus.

PERINEAL REGION.

Superficial Fascia. In the anterior half of the perineum this consists of two layers, the superficial fatty and the deep layer fibrous and well marked (fascia of Colles) : the latter is attached to rami of pubes and ischium, and from ischial tuberosity to central point of perineum ; here it joins the triangular liga- ment, by turning round the transversus perinei. It is con- tinuous in front with the dartos. and from its deep surface there is a septum passing forwards to scrotum in the middle line.

Triangular Ligament of the Urethra, or Deep Perineal Fascia, consists of two layers. The anterior layer is attached to the symphysis and to rami of pubes and ischium on each side, and joins the superficial fascia where this curves over the transversus perinei. About an inch below the symphysis it is perforated by the urethra, and above this by the dorsal vein of the penis, and on either side of this opening the dorsal artery and nerve of penis are transmitted. The posterior layer consists of two lateral portions separated in the median line by the urethra, and continuous with the recto-vesical fascia in the middle line, which here invests the prostate ; exter- nally it joins the obturator fascia on the pubic and ischial rami, and is really the subpubic part of the parietal pelvic fascia.

Parts between the two layers of the triangular ligament. Sub- pubic ligament, dorsal vein of penis, membranous part of urethra, compressor urethrae. Cowper's glands and ducts, internal pudic arteries giving off branches to bulb, to glands of Cowper, and the artery to corpus cavernosum, and the dorsal nerves of penis.

THE PELVIC FASCIA. Lines muscles of pelvis and forms f oor of outlet of pelvis. Consists of parietal and visceral layers.

Parietal Layer, (a) The Obturator Fascia. Covers inner surface of obturator internus. It is attached above to ilio- pectineal line, to oblique line on posterior surface of body of pubes from symphysis to upper part of thyroid foramen. Posteriorly it is attached to the anterior edge of the sacro- sciatic notch and large sacro-sciatic ligament, whilst below it is attached to the rami of pubis and ischium, and in front in the subpubic angle is continuous with the posterior layer of the triangular ligament. At th^ top of the thyroid foramen

48 THE POCKET ANATOMY

the fascia joins the obturator membrane, its bony attachment being here interrupted, and forms thus the floor of the short canal which transmits the obturator vessels and nerve. The upper part of the fascia is in the pelvic cavity, and is lined by peritoneum, whilst the lower part forms the outer boundary of the ischio-rectal fossa, and encases the internal pudic vessels and pudic nerve as they pass forwards.

(b) The Fascia of the Pyriformis is the continuation of the obturator fascia to the sacrum, and lies anterior to the pyri- formis and sacral plexus.

Visceral Layer. The Recto-vesical Fascia is attached in front to the posterior surface of the pubis, close to the obturator fascia, the origin of the levator ani intervening. Laterally it is attached to the obturator fascia along a line from the upper part ol the thyroid foramen to the ischial spine, whilst behind it joins the lower part of the pyriformis fascia. From these attachments it passes downwards and inwards over the upper surface of the levator ani to the prostate, bladder and rectum, joining the fascia of the opposite side in front of the bladder, and between the bladder and the rectum, thus form- ing the floor of the pelvis. Along the attachment of the recto- vesical to the obturator fascia is a thickened band, the white line of the pelvic fascia.

Processes from the recto-vesical fascia : —

Pubo -pro static ligaments or anterior true ligaments of the bladder. Narrow fasciculi, one on each side, passing from the back of the pubes to the front of the prostate and neck of the bladder.

Lateral true ligaments of the bladder. This is the anterior ligament prolonged laterally, and passes to the side of the prostate, and to the side of the bladder above the vesiculae seminalis, enclosing the prostatic plexus, whilst posteriorly it is attached to the bladder between the vesiculae, and is pro- longed downwards over and enclosing them, being joined to a like process from the opposite side.

Ligament of the rectum. A piece of fascia descends from the ischium and is attached to the rectum on each side.

In the female the vagina receives a prolongation of the recto-vesical fascia corresponding to the prostatic sheath.

Sphincter ani externus : tip and back of coccyx and sub- cutaneous fatty layer on either side(TF) — central perineal tendon(F) (4th sacral and inferior haemorrhoidal of pudic). [Closes anus.]

Sphincter ani internus : the involuntary muscular fibres of the large intestine thickened about \ inch deep. [Closes anus.]

MUSCLES 49

Bulbo-cavernosus, vel accelerator, vel ejaculator uriuae : central perineal tendon and raphe(v) — Posterior fibres. Under surface of triangular ligament(F). Middle fibres surround bulb and corpus spongiosum. Anterior fibres. Side of corpus cavernosum, and united with one on opposite side it encases dorsal vessels(A) (Deep perineal of pudic). [Compresses bulbous urethra, discharging its contents.]

Erector penis, vel ischio-cavernosus : internal surface of tuber ischii(TF) — internal and external surfaces of crus penis (T) (Deep perineal of pudic). [Compresses crus and produces erection.]

Transversus perinaei : internal surface of tuber ischii(T) — central perineal tendon(p) (Deep perineal of pudic). [Draws back and fixes central point of perineum.]

Levator ani : posterior surface of pubis near symphysis, spine of ischium, and between these two points from recto- vesical fascia, along attachment of obturator fascia(T) — central perineal tendon, sides of rectum and coccyx(p) (Perineal of pudic and Anterior division of 4th sacral). [Supports pelvic viscera, compresses and raises lower part of rectum in defaeca- tion.] Forms floor of pelvic cavity.

Compressor vel constrictor urethras : internal surface of pubic arch, posterior surface of triangular ligament(A) — muscle of opposite side(x) (Deep perineal of pudic). [Constricts urethra and expels contents.] Surrounds membranous portion of urethra.

Coccygeus : upper part of ischial spine, small sacro-sciatic ligament(TF) — side and anterior surface of coccyx and last piece of sacrum(p) (Anterior division of 4th sacral). [Supports pelvic floor.]

Note. — In the female the perineal muscles are essentially the same : for erector penis, read erector clitoridis, inserted into side of clitoris. The sphincter vagina, corresponding to ejaculator urinae, is attached to the central tendon of the perineum, and passing forwards on each side of the vagina — corpora cavernosa and body of clitoris.

MUSCLES AND FASCIAE OF LOWER EXTREMITY.

The FASCIA LATA of the thigh envelops the muscles and surrounds the limb. Above it is attached to the back of the sacrum and coccyx, to the iliac crest, to Poupart's ligament, pubic body and ramus, ischial tuberosity and ramus, and to the lower edge of the great sacro-sciatic ligament. The tlio- tibial band is a thickened part attached above to the iliac crest

4

5o THE POCKET ANATOMY

and below to the head of the fibula and outer tuberosity of the tibia. The fascia lata is attached below to the head of the tibia and sides of the patella, being strengthened by aponeuroses from the vasti muscles. Behind the fascia passes across between the hamstring muscles, enclosing the popliteal space.

The Saphenous Opening. This is an aperture in the fascia lata in upper and inner part of the thigh, through which the internal saphenous vein passes. It is covered by the cribri- form fascia. To describe it, the fascia is spoken of as con- sisting of two parts, of pubic portion on the inner side of the opening and continuous below with the iliac portion.

The pubic portion passes up over the pectineus, adductor longus and gracilis, and behind the femoral sheath, blending externally with sheath of psoas and attached internally to the pectineal line (Cooper ' s ligament) and to Gimbernat ' s ligament.

The iliac portion, on the outer side of the saphenous opening, and covering the femoral vessels, is attached exter- nally to the iliac crest, Poupart's ligament, and pubic spine, joining here the pubic portion. From the pubic spine it passes down and out with a free margin, the superior cornu or falciform process of Burns, forming the outer margin of the saphenous opening, and becoming continuous below and internally with the pubic portion, the margin here being well defined and named the inferior cornu.

Sheath of the Femoral Vessels. The upper part of the sheath surrounding the femoral vessels is called the crural sheath, which is formed by a prolongation from the transversalis fascia in front, and from the fascia covering the iliacus behind. It is divided into three compartments, the outer containing the artery, the middle one the vein, and the inner one, or crural canal, a lymphatic gland.

The crural canal, the innermost compartment of the femoral sheath, is about £ inch long, reaching from Gimbernat's liga- ment to the saphenous opening.

The upper opening of the crural canal is called the crural ring, which is on a level with Gimbernat's ligament, and is closed by a layer of sub-peritoneal fascia, the septum crurale.

Boundaries of the crural ring : —

In front, superficial (Poupart's ligament) and deep crural arches.

Behind, pubis, covered by pectineus ; pubic portion of fascia lata.

Internallv, Gimbernat's ligament, conjoined tendon.

Externally, femoral vein.

MUSCLES 51

The dsep crural arch is a thickened bundle of fibres of the transversalis fascia, attached to Poupart's ligament outside the femoral vessels, and passing across the femoral sheath to the ilio-pectineal line behind Gimbernat's ligament.

ILIAC REGION.

Psoas magnus : transverse processes and sides of bodies of all the lumbar and body of iath dorsal vertebrae(p) (the fleshy fibres are only attached to upper and lower margins of bodies, and intervertebral substances, being connected by a tendinous arch between) — small trochanter of femur, receiv- ing some fibres from the iliacus(T) (Branches from lumbar plexus). [A flexes thigh on trunk, and rotates femur out- wards; B flexes trunk on thigh.]

Psoas parvus : bodies of i2th dorsal and ist lumbar vertebrae and intervertebral disc(F) — ilio-pectineal line(T) (Branch from lumbar plexus). [Flexes lumbar spine.] Fre- quently absent.

Iliacus : upper half of iliac fossa, ilio-lumbar ligament, ala of sacrum, and capsule of hip-joint(F) — tendon of psoas, triangular surface anterior to and below the small trochanter (F) (Anterior crural). [A flexes hip-joint and rotates femur outwards ; B flexes trunk on thigh.] Passes beneath Poupart's ligament with the psoas.

ANTERIOR FEMORAL REGION.

Tensor fasciae femoris : outer edge of iliac crest for one inch, anterior superior iliac spine, and half notch below it(A) —fascia lata(ilio-tibial band) about £ down thigh, anterior to great trochanter(p) (Superior gluteal). [Makes fascia lata tense, rotates inwards, and abducts femur.]

Sartorius : anterior superior iliac spine and half notch below (A) — inner side of tibia, by side of tubercle, reaching by its upper edge as far back as internal lateral ligament(AT) (Middle cutaneous or special branch from anterior division of anterior crural). [Flexes hip and knee, abducts and rotates thigh out.] Longest muscle of body, crosses thigh obliquely, forming outer boundary of Scarpa's triangle; lies over the roof of Hunter's canal; lower tendon pierced by patellar branch of long saphenous nerve.

Quadriceps extensor— composed of:—

Vastus externus : upper half of shaft of femur, thus : — from base of neck, anterior and outer parts of base of great' tro- chanter. and line from great trochanter to linea aspera, upper half of external lip of linea aspera, external intermuscular

4—2

52 THE POCKET ANATOMY

septum(AF) — common extensor tendon, and slip to outer side ofpatella(x) (Anterior crural).

Vastus internus : inner lip of linea aspera, lower part of spiral line, tendons of adductores longus and magnus(TA) — common tendon and inner side of patella(x) (Anterior crural).

Crureus : upper § anterior and outer surfaces of shaft of femur, lower half external intermuscular septum(p) — common tendon (A) (Anterior crural).

Rectus femoris : ist head. Anterior inferior iliac spine(x). 2nd head. Groove above acetabulum(T) — common extensor tendon into upper border of patella(x) (Anterior crural).

THE COMMON EXXENSOR XENDON is inserted into the upper and lateral edges of the patella, very few fibres being prolonged over bone to help form the ligamentum patellae. [Extends knee ; rectus also flexes hip.]

Subcrureus : two slips from anterior surface of shaft of femur in lower fourth(p) — synovial sac of knee-joint(F) (An- terior crural). [Pulls up synovial expansion of knee-joint in extension.]

INXERNAL FEMORAL REGION.

Gracilis : internal margin of anterior surface of descending pubic ramus — inner side of tibia superior to semi-tendinosus, but inferior to backward prolongation of insertion of sartorius (x) (Anterior branch of obturator). [Adducts thigh, flexes knee.]

Pectineus : ilio-pectineal line and triangular surface anterioi to it(p) — posterior to small trochanter and upper half of line leading from it to linea aspera(x) (Anterior crural, and Acces- sory obturator or Obturator). [Adducts thigh, flexes hip, rotates thigh out.]

Adductor longus : anterior surface of pubes below angle of crest and symphysis(x) — inner lip of linea aspera(F) (Anterior division of obturator). [Adducts thigh, flexes hip, rotates thigh out.] Forms internal boundary of Scarpa's triangle.

Adductor brevis : body and ramus of pubis, extending from adductor longus to middle of ramus(FA)— behind pectineus into line leading from small trochanter to linea aspera(r) (Obturator, generally anterior branch). [Adducts thigh, flexes hip, rotates thigh out.] Anterior division of obturatornerve placed in front and posterior part behind, the internal circumflex artery between upper border and obturator externus.

Adductor magnus : pubic arch, from body of pubis to tuber ischii(A) — Anterior part. Line from great trochanter to linea aspera, inner lip of linea aspera, upper half of line leading

MUSCLES 53

to inner condyle(p). Posterior part. Tubercle above inner condyle(x) (Posterior division of obturator, Great sciatic). [Adducts thigh ; rotates thigh out ; posterior fibres extend hip- joint.] Between the two parts of the muscle there is an interval, the femoral opening, which transmits the femoral vessels.

HUNTER'S CANAL. Extends from the apex of Scarpa's triangle to the opening in the adductor magnus, containing the superficial femoral vessels and long saphenous nerve. It is formed by aponeurotic fibres passing from the adductores magnus and longus to the vastus internus, and is covered by sartorius.

GLUTEAL REGION.

Gluteusmaximus : external surface of ilium between superior curved line and posterior £ of outer lip of crest, aponeurosis over erector spinae, posterior surfaces of coccyx, and of last 2 pieces of sacrum, and great sacro sciatic ligament(F) — gluteal ridge between linea aspera and great trochanter(AF), fascia lata^F) (Inferior gluteal). [A, extensor and rotator out- wards of thigh ; B, after stooping, extends trunk on thigh.]

Parts beneath the glutens maximus : part of gluteus mediua the pyriformis, superior and inferior gemelli, tendon of obturator internus, quadratus femoris, upper part of adductor magnus, origins of semi-membranosus, semi-tendinosus, and biceps and part of vastus externus. Superficial branch of gluteal artery and superior gluteal nerve, sciatic vessels, and great and small sciatic nerves, internal pudic vessels and pudic nerve, nerve to obturator internus, inferior gluteal nerve, branches of external and internal circumflex and ist per- forating arteries. Three bursae, one over great trochanter, one over tuber ischii, one over vastus externus. Great sacro- sciatic ligament. Great trochanter and tuber ischii.

Gluteus medius : bone between iliac crest and superior curved line above, and middle curved line below, fascia(p) — outer surface of great trochanter from tip posteriorly to base anteriorly(p) (Superior gluteal). [Extends and abducts thigh : anterior fibres rotate thigh inwards, posterior out- wards.] Conceals gluteal vessels and nerve.

Gluteus minimus : posterior surface of hip-bone between middle and inferior curved lines(p) — impression on anterior part of great trochanter(p) (Superior gluteal). [Abducts and rotates thigh inwards.]

Pyriformis : anterior surface of sacrum, from 2nd, 3rd, and 4th pieces between anterior foramina, upper margin of great sciatic notch, great sacro-sciatic ligament(p)— posterior part

54 THE POCKET ANATOMY

of upper edge of great trochanter(x) (ist and and Sacral). [Rotates the thigh outwards.] Goes through great sacro-sciatic foramen.

Obturator interims : posterior surfaces of pubic arch, obtu- rator membrane, and ischium behind ; from great sciatic notch, fascia(F) — front of upper border of great trochanter with the gemelli(T) (Sacral plexus). [External rotator of thigh.] Passes through small sacro-sciatic foramen.

The obturator membrane closes the thyroid foramen, except at the upper and outer part, where a canal is left for the obturator vessels and nerve.

Gemellus superior : outer surface of ischial spine(F) — superior border of great trochanter anterior to the pyriformis with obturator internus(x) (Sacral plexus). [Rotates thigh outwards.]

Gemellus inferior : superior and outer border of tuber ischii (F) — superior border of great trochanter with obturator in- ternus(T) (Sacral plexus). [Rotates thigh outwards.]

Obturator externus : anterior half of outer surface of obtu- rator membrane, rami of pubis and ischium(F) — digital fossa at root of great trochanter(x) (Posterior division of obturator). [Rotates thigh outwards.]

Quadratus femoris : external border of tuber ischii(F) — tubercle on posterior inter-trochanteric ridge, and downwards as far as insertion of adductor magnus(p) (Sacral plexus). [External rotator and adductor of thigh.]

POSTERIOR FEMORAL REGION.

Biceps : Long head. Lower and inner impression on tuber ischii, and great sacro-sciatic ligament(T). Short head. Outer lip of linea aspera in the lower half, upper part of line to ex- ternal condyle, external inter-muscular septum(F) — by two slips embracing the external lateral ligament upon the outer side of head of fibula(T) (Great sciatic). [Flexes knee and extends thigh, rotates leg outwards.] Forms outer hamstring.

Semi-tendinosus : lower and inner impression on tuber ischii with the biceps(x), tendon of biceps(p)— upper part of internal surface of tibia, under cover of the sartorius(x) (Great sciatic). [Extends thigh, flexes knee, and rotates leg inwards.]

Semi-membranosus : upper and outer impression on the tuber ischii(x) — (i) hinder part of lower lip of groove on internal tibial tuberosity(x) beneath internal lateral ligament • — (2) forms principal part of posterior ligament of knee — (3) into fascia over popliteus (Great sciatic). [Extends thigh, flexes knee, and rotates leg inwards.]

MUSCLES 55

ANTERIOR TIBIO-FIBULAR REGION.

Tibialis anticus : external tuberosity and upper § of external surface of shaft of tibia, contiguous interosseous membrane, fascia and intermuscular septum (F) — inner surface of internal cuneiform ; base of metatarsal bone of great toe(r) (Anterior tibial). [Flexes ankle and extends tarsal joints, adducts and inverts foot.] Passes through innermost compartment of anterior annular ligament. Outer border conceals anterior tibial vessels.

Extensor proprius hallucis : middle f of anterior surface of shaft of fibula, contiguous interosseous membrane(F) — base of last phalanx of great toe(x) (Anterior tibial). [Flexes ankle, extends tarsal joints and great toe.] Anterior tibial vessels lie on the inner side, but the tendon crosses to inner side of vessels under anterior annular ligament.

Extensor longus digitorum : external tuberosity of tibia, head and upper £ of anterior surface of shaft of fibula, inter- osseous membrane(F) — by four tendons into the middle and last phalanges of four outer toes(x) (Anterior tibial). [Flexes ankle, extends joints of tarsus and toes.]

Peroneus tertius : lower £ of anterior surface of shaft of fibula, interosseous membrane, intermuscular septum(F) — base of 5th metatarsal on dorsal surface(x) (Anterior tibial). [Flexes ankle and extends tarsal joints, everting the foot.]

POSTERIOR TIBIO-FIBULAR REGION, SUPERFICIAL LAYER.

Gastrocnemius : Inner head. Impression on upper and posterior part of. inner condyle(T), line above condyle(F). Outer head. Impression on external surface of outer con- dyle(x), upper and posterior part of condyle(F) — unites with tendon of soleus to form tendo Achillis, inserted into lower half of posterior surface of os calcis(T) (Internal popliteal). [Flexes knee and extends ankle.]

Soleus : posterior surface of head, and upper J of posterior surface of shaft of fibula, oblique line and middle £ of internal border of tibia, fibrous arch over vessels(A) — tendo Achillis (Internal popliteal and posterior tibial). [Extends ankle.] Posterior tibial vessels and nerve lie beneath.

Plantaris : line above outer condyle, posterior ligament of knee-joint(F) — tuber calcis, with or by inner side of tendo Achillis(x) (Internal popliteal). [Flexes knee and extends ankle.] Tendon, longest in body.

56 THE POCKET ANATOMY

POSTERIOR TIBIO-FIBULAR REGION, DEEP LAYER.

The FASCIA of the leg invests the limb except where the inner surface of the tibia is subcutaneous ; it is continuous above with the fascia lata of the thigh, and below with the annular ligaments of the ankle, being attached in front to the anterior and inner borders of the tibia, and to the antero- and postero-external borders of the fibula, forming inter- muscular septa.

Popliteus : anterior half of impression on external surface of outer condyle(T), posterior ligament of knee-joint(p) — triangular space on posterior surface of shaft of tibia above oblique line(p) (Internal popliteal). [Flexes knee and rotates leg inwards.] Forms floor of popliteal stace ; arises in capsule of joint but outside synovial membrane.

Flexor longus hallucis : lower § of posterior surface of shaft of fibula, intermuscular septum (F) — base of last phalanx of great toe(x) (Posterior tibial). [Extends ankle, flexes tarsal joints and joints of great toe.] Grooves astragalus.

Flexor longus digitomm : inner part of posterior surface of shaft of tibia, from oblique line to 3 inches from lower end, aponeurosis over tibialis posticus(F) —four tendons, joined by flexor accessorius, passing through slits in tendons of flexor brevis digitorum, to bases of last phalanges of four outer toes (T) (Posterior tibial). [Extends ankle, flexes joints of tarsus and four outer toes.]

Tibialis posticus : posterior surface of interosseous mem- brane except below, and aponeurosis superficial to muscle, external part of posterior surface of tibia from head to 2 inches from lower end, internal surface of shaft of fibula(r) — tubercle on scaphoid bone, slips to cuneiform, cuboid, bases of and, 3rd, and 4th metatarsals, and sustentaculum tali(T) (Posterior tibial). [Extends ankle, flexes and supports tarsal joints, inverts foot.]

FIBULAR REGION.

Peroneus longus : upper | external surface of shaft of fibula, fascia, intermuscu lar septum(p) — outer part of plantar sur face of internal cuneiform and of base of ist metatarsal(T ) (Musculo-cutaneous). [Extends ankle-joint and everts foot.] Winds round grooves behind external malleolus and outer border of cuboid bone.

Peroneus brevis : lower $ external surface shaft of fibula, intermuscular septum(F)— projection at base of 5th meta- tarsal(x) (Musculo-cutaneous). [Extends ankle-joint and everts foot.]

MUSCLES 57

THE ANTERIOR ANNULAR LIGAMENT consists of two parts. A superior or vertical part, attached to the anterior border of the tibia internally, and to the anterior border of the fibula externally, being continuous above with the fascia of the leg, and divided into two compartments, the internal one for the tibialis anticus tendon, which alone has a synovial sheath, the outer one for the extensor longus digitorum and peroneus tertius tendons. An inferior or horizontal part, which is attached externally to the upper surface of the os calcis, passes inwards across the foot and divides, the upper band being attached to the inner malleolus, the lower to the fascia over the foot. It contains three compartments, with separate synovial sacs, the internal one for the tibialis anticus tendon, the middle one for the extensor proprius hallucis tendon, and the external one for the extensor longus digitorum and peroneus tertius tendons.

THE INTERNAL ANNULAR LIGAMENT passes between the inner malleolus and the inner margin of the os calcis, being continuous above with the deep fascia, and below with the plantar fascia. It is divided into three compartments. The one next the malleolus transmits the tibialis posticus tendon, the next one the flexor longus digitorum, and the lowest, on the astragalus, the flexor longus hallucis. Between these last two canals the posterior tibial vessels and nerve pass under the ligament.

THE EXTERNAL ANNULAR LIGAMENT passes from the outer malleolus to the os calcis, binding down the peronei tendons.

THE PLANTAR FASCIA consists of a central and two lateral parts.

The inner part covers the abductor hallucis, and is con- tinuous with the dorsal fascia.

The outer part covers the abductor minimi digiti, and ex- tends from the external tubercle of the os calcis to the base of the 5th metatarsal.

The central part is attached behind to the internal tubercle of the os calcis, and, extending forwards, splits up into five parts at the heads of the metatarsal bones, one part passing to each of the toes.

FOOT, DORSAL REGION.

Extensor brevis digitorum : superior surface of os calcis in front of groove, anterior annular ligament(F) — four tendons, inner one to base of ist phalanx of great toe, rest to outer side of tendons of long extensor to 2nd, 3rd, and 4th toes(T)

58 THE POCKET ANATOMY

(Anterior tibial). [Extends toes and flexes tarsal joints.] Inner tendon crosses dorsalis pedis artery.

FOOT, PLANTAR REGION, 1ST LAYER.

Abductor hallucis : inner side of large tubercle on under surface of os calcis, plantar fasci-a, internal annular ligament (p)-»-inner side of base of ist phalanx of great toe(-r) (Internal plantar). [Abducts great toe.]

Flexor brevis digitorum : front part of inner tubercle of os calcis(T), plantar fascia(F), intermuscular septa(p) — four tendons, which on the ist phalanx divide into two, allowing long flexor tendons to pass through ; the slips then reunite and are inserted, again separating, into the sides of the bases to middle phalanges of four outer toes(T) (Internal plantar) [Flexes tarsal joints and first interphalangeal joint of toes.]

Abductor minimi digiti: outer tubercle and fore part of inner tubercle of os calcis, plantar fascia, intermuscular septa(r) — outer side of base of ist phalanx of little toe (External plantar). [Abducts little toe.] -

FOOT, PLANTAR REGION, 2ND LAYER.

Flexor accessorius : Inner head. Inner concave surface of os calcis(p). Outer head. Outer surface of os calcis in front of outer tubercle, long plantar ligament (T) —long flexor t-ndons(p) (External plantar). [Flexes toes, correcting obliquity of pull of the flexor longus digitorum.]

Lumbricales : long flexor tendons, from adjacent sides of two tendons, except most internal one, which arises from inner side of ist flexor tendon (F) — inner sides of bases of ist phalanx of four outer toes, and dorsal expansion of extensor tendon(T) (Internal plantar, ist ; External plantar, 2nd, 3rd, and 4th). [Flex metatarso-phalangeal and extend inter- phalangeal joints.]

FOOT, PLANTAR REGION, 3RD LAYER.

Flexor brevis hallucis: internal border of cuboid and adjacent part of external cuneiform(T), tendon of tibialis posticus(T) — outer and inner sides of base of ist phalanx of great toe(T) (Internal plantar). [Flexes great toe and adducts it to middle line of foot.]

Adductor obliquus hallucis ; bases of 2nd, 3rd, and 4th metatarsals, sheath of peroneus longus(p) — outer side of base of ist phalanx of great toe(T) (External plantar). [Adducts great toe.]

Adductor transversus pollicis : capsules of metatarso-

ARTERIES 59

phalangeal joints of three outer toes(p) — outer side of base of ist phalanx of great toe (x) (External plantar). [Binds toes together and adducts great toe.]

Flexor brevis minimi digiti : base of 5th metatarsal, sheath of peroneus longus(p) — outer side of base of ist phalanx of little toe(T) (External plantar). [Flexes metatarso-phalangeal joint of the little toe.]

FOOT, PLANTAR AND DORSAL INTEROSSEOUS REGION.

Interossei dorsales (4) : by two heads from adjacent sides of metatarsal bones(p) — side of and dorsal extensor expansion on tst phalanx thus : the inner two go to and toe, one on each side, outer two to outer sides of 3rd and 4th toes respec- tively^) (External plantar). [Abduct from middle line of 2nd toe.]

Interossei plantares (3) : under and inner surfaces of three outer metatarsal bones(p) — inner side of base of ist phalanx of same toes(T), and dorsal expansion on ist phalanx(T) (External plantar). [Adduct to middle line of 2nd toe.]

THE ARTERIES.

ARTERIES OF HEAD AND NECK.

THE SUBCLAVIAN ARTERIES. — Extent : Right, from innomi- nate opposite right sterno-clavicular articulation. Left, from transverse part of arch of aorta. Both pass into neck, arching outwards over pleura; lying on first rib, between scalenus anticus and medius, to end at outer border of it.

Divisions : The scalenus anticus, passing anteriorly to artery, 'is 'used to divide it into three parts, viz. : —

ist part, from origin of vessel to inner border of scalenus anticus.

2nd part, portion posterior to scalenus anticus.

3rd part, from outer edge of scalenus to external border of ist rib.

5o

THE POCKET ANATOMY

RELATIONS OF THE 1ST PART OF THE RIGHT SUBCLAVIAN.

In Front.

Below.

Behind.

Skin.	Internal ju-	Pleura. Pleura.
Superficial fascia. Platysma. Deep fascia.	gular Vertebral Anterior ju-	«5 Rscurrent laryn- Recurrent \ •3 geal nerve. laryngeal > and cardiac
Sterno-mas- > „,-	gular	branches of
toid JJ Sterno-hyoid V «	Pneumogas- tric	vagus. Sympathetic
Sterno-thy- 1 4j	Sympathetic	u5 loop with
roid )	loop and	. > lower
Below and in	superior cervical	u cardiac ^ branches. /
Front.	cardiac	Longus colli
Subclavian ^ rf Commence- 1 c mentofin- f'%	branch.	muscle.
nominate J

RELATIONS OF 1ST PART OF LEFT SUBCLAVIAN.

In Front.

Inner Side.

Behind.

Skin. Superficial fascia. Manubrium	Anterior ju- " gular Internal ju-	§	Left carotid. Trachea. (Esophagus.	Longus colli. (Esophagus. Thoracic duct
sterni.	gular		Thoracic duct	(below).
Platysma.	Left innomi-	>	Pneumogastric.	Inferior cervical
Deep fascia.	nate		Lower cardiac	ganglion.
Sterno-mas- ^ .	Vertebral		branches of	Cord of sympa-
toid JJ Sterno-hyoid V "	Left phrenic " Left vagus	i	sympathetic. Left recurrent	thetic. Pleura.
Sterno-thy- I M roid J *	Sympathetic loop	%	laryngeal nerve.	Outer Side and
Left common	Thoracic duct		Behind.
carotid artery.	(above).		Left lung.
			Pleura.

RELATIONS OF 2ND PART OF SUBCLAVIAN.

In Front.	Behind. Below
Skin.	Subclavian vein	Pleura and lung. Pleura.
Superficial fascia. Platysma. Deep fascia.	(below level). Phrenic nerve (on right side).	Above. Brachial plexus.
Sterno-mas- ^ ^
toid (clavi- 1 J"
cular origin) V &
Scalenus anti- 1 £

ARTERIES 61

RELATIONS OF 3RD PART OF SUBCLAVIAN.

Contained in subclavian triangle, and enclosed in tube 01 deep cervical fascia.

lit Front. Below.

Skin. Supra-scapular artery. ist rib.

Superficial fascia. Clavicle.

Descending cutaneous Subclavius. tientnd.

branches of cervical Nerve to subclavius. Scalenus medius.

plexus. Lowest bracliial

Platysma. Above. aerve trunk.

Deep fascia. Brachial plexus.

External jugular - Subclavian Branch from cephalic

to external jugular Supra-scapular Transverse cervical Anterior jugular

BRANCHES FROM THE IST PART.

VERTEBRAL : from upper and back part. Passes upwards and backwards, behind inferior thyroid artery and internal jugular and vertebral veins, then between scalenus anticus and longus colli, to enter foramen in transverse process of 6th cervical vertebra. Ascends in corresponding foramina as far as axis, having vertebral vein in front, and cervical nerves behind. It then passes outwards and upwards, through foramen in atlas, and winds backwards and inwards in verte- bral groove of atlas, lying on the floor of the suboccipital triangle, having the trunk of the ist cervical nerve beneath it, and the posterior branch of same nerve crossing it behind. It pierces posterior occipito-atloid ligament and dura mater, and enters skull through foramen magnum. It then winds round bulb, passing between hypoglossal and anterior root of ist cervical nerve to front of medulla, uniting with fellow, to form the basilar artery (p. 73), at the lower border of the pons.

Cervical Branches : —

Lateral spinal : each enters spinal canal through an inter- vertebral foramen, dividing into posterior to supply cord and membranes, and anterior to supply bodies of vertebrae.

Muscular : to deep cervical muscles.

Cranial Branches : —

Posterior meningeal : arises before vertebral pierces dura mater opposite foramen magnum, to falx cerebelli. and dura in posterior fossa

62 THE POCKET ANATOMY

Posterior spinal : arises opposite posterior part of medulla, passes down back of cord behind roots of nerves, anasto- mising with spinal branches coming through intervertebral foramina.

Anterior spinal : given off near end of artery, descends in front of medulla, unites with opposite fellow just below fora- men magnum to form a single artery, which is continued along the cord, anastomosing like the posterior artery ; sup- plies pia mater and cord.

Posterior inferior cerebellar : arising near pons, passes backwards and outwards between roots of hypoglossal and then between spinal accessory and pneumogastric nerves, to reach under surface of cerebellum ; divides into two branches, one continuing backwards in sulcus between two hemispheres, the other outwards to supply under surface of cerebellum ; anas, superior cerebellar. Supplies hemisphere, vermiform process, and choroid plexus of 4th ventricle.

Bulbar arteries enter medulla.

THYROID AXIS : a short thick trunk from front of artery near scalenus anticus, quickly dividing into : —

Inferior thyroid : passes upwards on vertebral artery and under internal jugular vein ; then inwards and downwards behind sheath of carotid and sympathetic (middle cervical ganglion), finally outwards and upwards to under part of thy- roid body ; anas, opposite fellow and superior thyroid.

Branches : —

Ascending cervical: arises as inferior thyroid turns behind carotid sheath, ascends parallel to phrenic nerve and between scalenus anticus and rectus anticus major, supplying them, the cord and its membranes.

Inferior laryngeal : upwards on trachea to back of larynx, with recurrent laryngeal nerve.

Tracheal : to trachea ; anas, bronchial.

CEsophageal : to supply resophagus.

Thyroid : to gland.

Muscular.

Supra- scapular : runs downwards at first, over scalenus anticus and phrenic nerve, crosses 3rd part of subclavian, then runs transversely outwards, behind and parallel to clavicle, to upper edge of scapula under cover of trapezius ; inclining downwards with nerve to pass over transverse liga- ment on supra-scapular notch, enters supra-spinous fossa in contact with the bone beneath supra-spinatus, which it sup- plies. It then winds over neck of scapula to infra-spinous fossa ; anas, with posterior scapular and dorsalis scapulae.

ARTERIES 63

Branches : —

Muscular: to neighbouring muscles, ^ecially sterno- mastoid.

Supra-acromial : through trapezius to acromion ; anas, acro- mio-thoracic.

Subscapular : arises as suprascapular passes over notch ; anas, in subscapular fossa with posterior scapular and sub- scapular of axillary.

Injra-spinous : descends on neck of scapula to fossa ; anas. dorsal of subscapular and posterior scapular.

Articular: to shoulder-joint. Nutrient: to scapula.

Transverse cervical : over scaleni muscles, phrenic nerve, and brachial plexus, under omohyoid, to outer edge of levator anguli scapulae, there dividing into : —

Superficial cervical : ascends beneath anterior edge of tra- pezius, supplying it together with glands, integuments and muscles of that region ; anas, superficial branch of arteria princeps cervicis.

Posterior scapular : backwards to superior angle of scapula beneath levator anguli scapula?, then downwards along verte- bral border of scapula under the rhomboids supplying sur- rounding muscles ; anas, supra-scapular, subscapular.

INTERNAL MAMMARY: from under surface of suDclavian just below thyroid axis, runs down behind clavicle and subclavian vein to posterior surface of ist costal cartilage, being crossed here by phrenic nerve; downwards between pleura and costal cartilages, crossed by intercostal nerves and lying on tri- angularis sterni as far as the 6th space, there dividing into two terminal branches.

Branches : —

Comes nervi phrenici (superior phrenic) : arises high in chest, accompanies phrenic nerve between pleura and pericardium to diaphragm, supplying it; anas, musculo-phrenic, inferior phrenic.

Mediastinal : to areolar tissue of anterior mediastinum and thymus gland.

Pericardiac : to upper part of pericardium.

Sternal : to triangularis sterni and sternum.

A nterior Intercostal : to upper five or six intercostal spaces, two in each space ; anastomose with aortic intercostal.

Perforating : perforate upper five or six intercostal spaces to supply pectoral muscles and mammary gland.

Musculo-phrenic : external of two terminal branches per forates diaphragm about gth intercostal space, supplying dia- phragm, and branches to lower intercostal spaces.

<>4 THE POCKET ANATOMY

Superior epigastric : internal terminal branch passes behind yth costal cartilage and pierces diaphragm, lies posterior to rectus within the sheath, terminating in that muscle; anas. deep epigastric of external iliac.

BRANCH FROM THE 2ND PART.

SUPERIOR INTERCOSTAL : from upper and back part behind scalenus anticus, bends backwards over pleural dome in front of neck of ist rib to ist and 2nd intercostal spaces, supplies small branches to cord and deep spinal muscles. On the neck of the ist rib, the ist intercostal nerve is external, and ist thoracic ganglion of sympathetic, internal to artery.

Branch : —

Deep cervical : corresponds to posterior branch of an aortic intercostal ; passes between transverse process of yth cervical vertebra and ist rib, ascending beneath complexus to axis ; anas, vertebral, and deep branch of arteria princeps cervicis of occipital.

THE COMMON CAROTID ARTERY.

THE COMMON CAROTID ARTERY : On the right side, arises from the innominate, at its bifurcation behind the right sterno-clavicular articulation. On the left side, from the highest or transverse part of aortic arch, and is consequently longer than the right artery, and more deeply placed in the thorax at its origin. It ascends obliquely to the neck.

Relations of the Left Common Carotid in the Thorax.

In Front.	Behind.	Left Side.
Skin. Superficial fascia. Deep fascia. Part of pectoralis	Sterno-hyoid and Sterno-thyroid muscles. Left innominate	Trachea. (Esophagus. Thoracic duct. Left recurrent	Left subclavian artery. Left pneuraogas- tric and phrenic
major, ist piece of ster-	vein. Thymus gland.	laryngeal nerve.	nerves. Left pleura and
num.		Right Side.	lung.
		Innominate
		artery.

Extent. — In the neck the common carotid of either side ex- tends from sterno-clavicular articulation to opposite upper border of thyroid cartilage, there dividing into external and internal carotids.

Course. — A line drawn from sterno-clavicular articulation, to point midway between mastoid process ajad angle of irA- tprior maxilla.

ARTERIES

Relations of both Common Carotids in the Neck. Crossed about midway by omo-hyoid, and enclosed in same sheath of deep cervical fascia as internal jugular vein and pneumogastric nerve.

Part below Superior Border of Omo-hyoid.
In Front. Behind.	Inner Side.
Skin.	Internal ju- ""	Scalenus anticus.	Trachea.
Superficial fascia. Platysma. Deep fascia.	gular (over- laps on left side)	Longus colli. Inferior thyroid »5 artery.	CEsophagus. Recurrent laryn- geal nerve.
Sterno-mas- \ ioid (sternal J ^ origin) 1 ,« Sterno-hyoid V « Sterno-thy- ,5 roid 1 ^	Superior and middle thy- roid Anterior ju- gular j Descendens and	>-•— Vertebral artery. > Sympathetic ~\ . Recurrent 1 $ laryngeal v fc Pneumogas- j £ trie	Thyroid body. Superior thyroid artery.
Omo-hyoid /	communicans hypoglossi. Outer Sid*.
	Internal jugular.
	Pneumogastric.

Behind. Rectus capitis anticns major. Pneumogastric nerve. Sympathetic ,,

Inntr Side. Larynx. Pharynx. Superior thyroid artery. Outer Side. | Internal jugular.

Part above Omo-hyoid. In Front. Platysma. Deep fascia. Sterno-mastoid. D«cendens hypo- glossi.

Sterno-mastoid branch of superior thyroid.

BRANCHES of the Common Carotid Artery. Terminal only, viz., external and internal carotid.

EXTERNAL CAROTID. Extent. — From bifurcation of com- mon carotid opposite upper border of thyroid cartilage, to level of neck of condyle of inferior maxilla, there dividing into superficial temporal and internal maxillary.

Course. — Line of artery same as common carotid.

RELATIONS. Superficial. Behind.	Inner Sidt.
Skin.	Facial	•\	Pharynx.	Pharynx.
Superficial fascia. Platysma. Deep fascia. Sterno-mas- ~\ «j toid ha Digastric J 3 Stylo-hyoid J 3	Lingual Temporo- maxillary Hyp^glossal	\l h	Styloid process. Stylo-glossus. Stylo-pharyn- geus. Glosso-pharyn- geal nerve Internal carotid	Ramus of jaw. Stylo-maxillary ligament. Parotid gland. Superior ^j .% laryngeal I « External j !j
Parotid gland-			artery.	laryngeal J f
				5

66 THE POCKET ANATOMY

Anterior Branches of External Carotid.

Superior thyroid : given off just below great cornu of hyoid, curves downwards and forwards to thyroid body ; anas, fellow of opposite side, inferior thyroid.

Branches : —

Muscular: to muscles covering it. Sterna -mastoid branch passes downwards and outwards across sheath of common carotid, supplying sterno-mastoid and integument.

Infra hyoid : runs transversely inwards, along inferior border of hyoid ; anas, with opposite fellow.

Superior laryngeal : accompanies superior laryngeal nerve, pierceo thyro-hyoid membrane, supplies muscles, glands, and mucous membrane of larynx ; anas, opposite fellow.

Crico-thyroid : crosses crico-thyroid membrane transversely , anas, opposite fellow.

Thyroid : to upper and anterior part of gland.

Lingual : arises from anterior part of artery between superior thyroid and facial arteries, curves upwards and forwards on middle constrictor to tip of great cornu of hyoid, where it is crossed by hypoglossal nerve, thence forwards under hyo- glossus muscle, digastric and stylo-hyoid, parallel with hypo- glossal nerve, finally on genio-hyo-glossus upwards and for- wards to tip of tongue as ranine.

Branches : —

Supra-hyoid : along superior border of hyoid, supplying muscles, etc. ; anas, opposite fellow.

Dorsalis lingua: ascends to dorsum of tongue; anas, oppo- site fellow, supplies mucous membrane, tonsil, epiglottis, soft palate, etc.

Sublingtial : runs forwards and outwards to supply sub- lingual gland, adjacent muscles and mucous membrane.

Ranine : continuation of the lingual to tip of tongue, accom- panies gustatory nerve ; anas, opposite fellow.

Facial : arises near angle of inferior maxilla, directed for- wards and upwards beneath digastric and stylo-hyoid muscles in groove on deep surface of submaxillary gland to base of lower jaw, over which it ascends to face, being anterior tc masseter muscle ; ascending to inner canthus, imbedded in levator labii superioris alaeque nasi, where it takes name of angular, it rests successively upon lower jaw, buccinator, and levator anguli oris, with vein to outer side, and crossed by platysma, risorius, zygomaticus major, and sometimes by the levator labii superioris ; anas, ophthalmic

ARTERIES 67

Cervical Branches : —

Ascending or inferior palatine : between stylo-glossus and stylo-pharyngeus to pharynx near border of internal ptery- goid muscle ; after supplying muscles, tonsil, Eustachian tube, divides near levator palati into two branches, one going to supply soft palate, glands, etc. , the other to tonsil ; anas. tonsillar and artery of opposite side.

Tonsillar : penetrates superior constrictor of pharynx to supply tonsil and root of tongue; anas, ascending palatine.

Submaxillary (three or four) to supply submaxillary gland.

Submental : arises as artery turns round base of jaw, and runs forwards over mylo-hyoid, supplying it and digastric, then to symphysis, there dividing into superficial, which turns round chin ; anas, inferior labial and mental, and a deep branch perforates mylo-hyoid, supplying deep muscles ; anas. sublingual.

Facial Branches : —

Muscular : to masseter, buccinator, etc.

Inferior labial : runs beneath depressor anguli oris, to supply lower lip ; anas, inferior coronary, submental, mental.

Inferior coronary : arises near angle of mouth, tortuous course between mucous membrane of lower lip and orbicularis oris ; anastomoses with opposite fellow.

Superior coronary : arises with or near preceding, having corresponding course in upper lip ; anastomoses with opposite fellow, supplies a branch, artery of septum, to collu- mella of nose.

Lateral nasal : turns inwards beneath levator labii superioris alaeque nasi to supply ala and dorsum of nose ; anas, opposite fellow, nasal of ophthalmic, and infra-orbital.

Angular: terminal branch; anastomoses at inner canthus with nasal of ophthalmic.

Posterior Branches of External Carotid : —

Occipital : arising from the posterior part of artery, about opposite the facial, runs upwards and backwards beneath digastric, stylo-hyoid, sterno-mastoid, splenius, and trachelo- mastoid to interval between transverse process of atlas and mastoid process, then backwards in the occipital groove, and lying on rectus capitis lateralis, superior oblique and com- plexus ; lastly, piercing the trapezius near insertion, it ascends in company with the great occipital nerve to the back of scalp. Hypoglo^al nerve hooks round it at origin, and the artery crosses in the neck the internal carotid artery, pneumogastric and spinal accessory nerves and internal jugular vein.

5—2

68 THE POCKET ANATOMY

Branches :—

Muscular to digastric, stylo-hyoid ; stcrno-mastoid branch to supply that muscle.

Mastoid : through mastoid foramen to dura mater.

Posterior meningeal: ascends, in company with internal jugular vein, through jugular foramen to dura mater in posterior fossa.

Cervical (ramus princess cervicis) : at outer border of corn- plexus ; descends at back of neck ; superficial branch passes beneath splenius, supplying it and the trapezius, anas. superficial cervical ; deep branch, goes beneath complexus, anas, vertebral, deep cervical of superior intercostal.

Cranial : to muscles and integuments of occiput ; anas. opposite fellow, posterior auricular and superficial tem- poral.

Posterior auricular : arises opposite apex of styloid process, ascends in parotid to groove between pinna and mastoid pro- cess, dividing into anterior or auricular, anas, posterior division of temporal ; and. posterior or mastoid, anas, occipital. Joined near mastoid process by posterior auricular branch of the 7th nerve.

Branches : —

Stylo-mastoid : enters stylo-mastoid foramen, supplying tym- panum, mastoid cells, etc.

Auricular : to posterior part of concha.

Ascending branch of External Carotid : —

Ascending Pharyngeal : smallest branch, arising half an inch above origin of trunk, ascends between internal carotid and pharynx to base of skull.

Branches : —

Prevertebral : to rectus anticus, ist cervical ganglion, and gth, loth and nth nerves, glands, etc.

Pharyngeal (three or four) : inwards to pharynx, supplying constrictors, Eustachian tube, and a palatine branch to soft palate and tonsil.

Meningeal : one through foramen jugulare, another through anterior condylar foramen, and a third through foramen lacerum medium to supply dura mater.

Terminal Branches of External Carotid : —

Superficial temporal : smaller of two terminal branches, continues in the line of external carotid. Imbedded at first in parotid, crosses over root of zygoma in -front of auriculo- temporal nerve, upwards under skin fora inches, dividing intq two terminal branches.

ARTERIES 69

Branches : —

Parotid to gland.

Transverse facial : arises in parotid, accompanies transverse branches of facial nerve and parotid duct across face, lies above the duct, supplying muscles, glands, etc. ; anas, facial, infra-orbital.

Middle temporal : arises just above zygoma, perforates tem- poral fascia, supplying muscle ; anas, deep temporal.

Orbital (may come from middle temporal) : along zygoma between layers of temporal fascia to outer can thus.

Anterior auricular : to anterior portion of external ear ; anas. posterior auricular.

A nterior temporal : one of terminal branches, ascends over tero - poralfascia, supplying muscles, etc.; anas, frontal, supra- orbital.

Posterior temporal: curves backwards over temporal fascia and inosculates with opposite fellow; anas, posterior auricular, occipital.

Internal maxillary : larger of terminal branches, arises in parotid, at first (maxillary portion) curving forwards between jaw and internal lateral ligament, parallel with auriculo- temporal nerve and lying on internal pterygoid muscle and inferior dental nerve, then (pterygoid portion) forwards and outwards on outer (frequently on inner) surface of lower head of external pterygoid, finally (spheno - maxillary portion) enters spheno-maxillary fossa between two heads of origin of external pterygoid.

Branches from Maxillary portion : —

Tympanic : enters Glaserian fissure, supplies tympanum, and membrana tympani, generally gives off deep auricular to external auditory meatus ; anas, vidian, stylo-mastoid. (May come from middle meningeal.)

Middle or great meningeal : arises between internal lateral ligament and neck of conclyle, passes between two roots of auriculo-temporal nerve, through foramen spinosum of the sphenoid, dividing on great wing of sphenoid into anterior and posterior branches ; anterior going to anterior inferior angle of parietal, posterior to squamous of temporal ; anas, opposite fellow, anterior and posterior meningeal. The trunk of the artery gives off Gasserian, to ganglion. Petrosal : enters hiatus Fallopii ; anas, stylo-mastoid of posterior auricular. Orbital : through sphenoidal fissure to orbit. Temporal : through foramen in bone to join branches from deep temporal.

Small meningeal : through foramen ovale, supplies Gasserian ganglion and dura mater. (Generally a branch of the middle meningeal.)

7o THE POCKET ANATOMY

Inferior dental: descends with and behind inferior dental nerve through dental foramen on inner side of ramus of inferior maxilla, divides opposite ist bicuspid into incisor and mental, the former going to incisor teeth ; anas, opposite fellow : the latter comes out through mental foramen ; anas. sub-mental, inferior labial, inferior coronary. Mylo-hyoid branch given off as artery enters dental foramen, runs in mylo- hyoid groove to muscle. Lingual branch accompanies lingual nerve.

Branches from Pterygoid portion : —

Deep temporal (2) : anterior and posterior to temporal fossa between muscle and cranium ; anas, other temporal, lachrymal through foramina in malar bone.

Pterygoid : to pterygoid muscles.

Masseteric : passes over sigmoid notch to deep surface of masseter ; also supplies temporo-maxillary articulation.

Buccal: runs forward with buccal nerve between internal pterygoid and jaw to buccinator; anas, facial.

Branches of Spheno-M axillary Portion : —

Posterior superior dental, or alveolar : given off as artery passes into spheno-maxillary fossa ; descends on posterior aspect of maxilla with branch of superior maxillary nerve, enters posterior dental canals, supplying molars, bicuspids, antrum, gums, etc.

Infra-orbital: continuation of trunk, accompanies superior maxillary nerve through infra-orbital canal, appearing on face beneath levator labii superioris ; anas, facial and buccal. In the canal it gives off branches to orbit, and an anterior dental branch goes with nerve to supply front teeth ; anas. posterior dental. On the face it supplies lachrymal sac and inner canthus ; anas, ophthalmic ; and gives branches down- wards ; anas, transverse facial, buccal and facial.

Descending, or superior palatine : through posterior palatine canal with large palatine nerve, along hard palate, and through foramen of Stenson in anterior palatine fossa ; anas. artery of septum from facial and naso-palatine.

Vidian : through vidian canal with nerve, supplies Eusta- chian tube and tympanum.

Pterygo-palatine : backwards through pterygo-palatine canal with pharyngeal nerve to upper part of pharynx.

Nasal, or spheno-palatine : enters spheno-palatine foramen, supplying posterior ethmoidal cells, etc. Branch. Naso-pala- tine or artery of septum, runs along vomer; anas, descending palatine.

INTERNAL CAROTID. Extent. — From superior border of

ARTERIES 71

thyroid cartilage to Sylvian fissure of brain, there dividing into anterior and middle cerebral.

Course. — Extends directly upwards from common carotid to carotid canal of temporal bone ; entering canal passes upwards, internal to and then above Eustachian tube, then forwards and inwards, then alongside of sella Turcica in the cavernous sinus, having the 6th nerve on the outer side ; it turns upwards on inner side of anterior clinoid process, pierces dura mater, and divides between and and 3rd cranial nerves at anterior perforated spot into branches. No branches given off from cervical part.

RELATIONS IN THE NECK.

Superficial. Inner Side. Behind.

Skin. Pharynx. Internal jugular veil .

Superficial fascia. Ascending pharyngeal Rectus capitis anticus

Platysma. artery. major.

Deep fascia. Superior and external Sympathetic.

Sterno-mastoid. laryngeal nerves. Pneumogastric.

Parotid gland. External carotid. Digastric. Stylo-hyoid. Stylo-glossus. Stylo-pharyngeus. Occipital ) .,,*»««*-

Posterior auricular J ar1 Hypoglossal \

Glosso-pharyngeal l_-___ Pharyngeal branch fne of vagus J

Outer Side. Internal jugular vein.

Branch from Petrous portion : —

Tympanic : inconstant : through a foramen in carotid canal to tympanum ; anas, tympanic of internal maxillary and stylo- mastoid.

Branches from Cavernous portion : —

Pituitary : small branches to pituitary body, etc.

Meningeal : to dura mater in middle fossa.

Ophthalmic : arises at inner side of anterior clinoid process, enters orbit through optic foramen, external and below optic nerve ; it then crosses over nerve to inner angle of orbit to divide into two terminal branches, frontal and nasal.

Branches arising outside Optic Nerve : —

Lachrymal : accompanies lachrymal nerve over external rectus to lachrymal gland, gives off malar branches ; anas.

72 THE POCKET ANATOMY

deep temporal and transverse facial. Branch sent back to anas, middle meningeal through sphenoid fissure

Central of retina : pierces optic nerve, runs in its substance to retina (vide Eye) .

Branches arising over Optic Nerve : —

Posterior ciliary : divided into two sets. Short (10) perforate sclerotic and supply choroid. Long (2) pass forward between choroid and sclerotic; anas, anterior ciliary and supply iris and ciliary processes.

Supra-orbital : ascends with frontal nerve over muscles, etc., to supra-orbital foramen ; passing out, ascends over frontal bone ; anas, temporal, facial and frontal.

Branches arising internal to Optic Nerve : —

Muscular, superior and inferior : to muscles of orbit, give off anterior ciliary (6-8), which pierce sclerotic behind cornea.

Ethmoidal : anterior and posterior to ethmoidal cells, through anterior and posterior internal orbital canals respectively, supplying also dura mater, the anterior accompanying nasal nerve to skin of nose (anterior nasal branch).

Palpebral (2) : one for each lid, arise near pulley, form an arch in each lid, and supply lachrymal apparatus.

Terminal Branches : —

Frontal : turns upwards round inner margin of orbit ; anas. supra-orbital.

Nasal : over tendo oculi to root of nose ; anas, nasal and angular of facial.

Branches from Cerebral Portion of Internal Carotid : —

Anterior cerebral : arises at inner extremity of fissure of Sylvius, passes forwards in great longitudinal fissure. Oppo- site arteries united by anterior communicating. It then curves round fore part of corpus callosum, supplying offsets to corpus callosum, frontal and parieto-occipital sulci, and to anterior perforated spot.

Middle cerebral: largest offset, enters fissure of Sylvius, dividing into branches for external surface of hemisphere, and interior of brain, the latter entering anterior perforated spot. Internal branches: Caudate, thalamic, and lenticulo- striate. External branches: Frontal, parietal, parieto-tem- poral, and temporal.

Posterior communicating: from posterior part of artery, runs backwards ; anas, posterior cerebral of basilar.

Anterior choroid : from back part of artery, passes backwards and outwards to enter descending horn of lateral ventricle, just beneath edge of middle lobe ; supplies

ARTERIES 73

hippocampus major, corpus fimbriatum, and choroid plexus.

THE BASILAR ARTERY : formed by union of the two ver- tebral arteries. Extent, from lower to upper border of pons, there dividing into posterior cerebrals.

Branches : —

Transverse (4 or 6) : twigs to supply pons and internal auditory, an offset to internal ear, with auditory nerve.

Anterior inferior cerebellar : backwards to anterior part of inferior surface of cerebellum ; anas, posterior inferior cere- bellar of vertebral.

Superior cerebellar: arises near termination, to upper surface of cerebellum, winding round crus cerebri behind 3rd nerve ; anas, opposite fellow, inferior cerebellar.

Posterior cerebral (2) : one on each side, terminal of basilar, winds backwards round crus in front of 3rd nerve, passes upwards to under surface of posterior cerebral lobes, joined near crus by posterior communicating, and gives off : — Postero- median to posterior perforated spot ; Posterior choroid to choroid plexus through transverse fissure ; Postero-lateral to optic thalamus ; Cortical branches : temporal, calcarine, parieto- occipital ; anas, anterior and middle cerebral.

CIRCLE OF WILLIS : a name given to the anastomoses between the vertebral and internal carotid arteries at base of brain. The internal carotid sends forward the anterior cerebrals, which are connected by the anterior communi- cating. The basilar sends forwards the posterior cerebrals, which are joined to the carotid by the posterior communicating arteries.

ARTERIES OF UPPER LIMB.

THE AXILLARY ARTERY.

Extent. — From outer border of ist rib to lower border of teres major insertion. Divided into three parts : —

IST PART. Extent. — From outer border of ist rib to upper border of pectoralis minor.

Relations. — In front. Pectoralis major, costo-coracoid mem- brane, cephalic vein, external anterior thoracic nerve, and branches of acromio-thoracic artery and vein.

Behind, ist intercostal space and muscle, ist serration of serratus magnus, posterior thoracic nerve.

Inner side. Internal anterior thoracic nerve and axillarj vein. Outer side. Brachial plexus.

74 THE POCKET ANATOMY

2ND PART. Extent. — From superior to inferior border oi pectoralis minor.

Relations. — In front. Pectorales major and minor. Behind. Subscapularis, posterior cord of plexus. Outer side. Outer cord of plexus. Inner side. Inner cord of plexus, separating artery from

3RD PART. Extent. — From inferior border of pectoralis minor to lower border of teres major.

Relations. — In front. Pectoralis major, inner head of median and internal cutaneous nerves ; below, skin and fasciae.

Behind. Subscapularis, tendons of latissimus dorsi and teres major, musculo-spiral and circumflex nerves.

Inner side. Uln'ar nerve, axillary vein, and lesser internal cutaneous nerve.

Outer side. Coraco - brachialis, median and musculo- cutaneous nerves.

Branches : —

Superior thoracic (ist part) : arises opposite ist intercostal space, supplies pectorales ; anas, internal mammary, inter- costals.

Acromio-thoracic (ist part) : arises from front of artery just above pectoralis minor.

Branches : —

Acromial : supply and perforate deltoid; anas, branch of supra-scapular and posterior circumflex.

Humeral : accompanies cephalic vein ; anas, anterior circumflex.

Thoracic : two or three branches to supply side of thorax ; anas, intercostal,

Clavicular : one or two twigs to clavicle and subclavius.

Long thoracic (and part) : passes downwards along inferior border of pectoralis minor to about 6th intercostal space, supplies pectorales and serratus magnus ; anas, intercostal and other thoracic branches. In female gives branches to mammary gland : external mammary.

Alar thoracic (and part) : supplies glands and fat of the axilla ; not a constant separate branch.

Subscapular (3rd part) : arises opposite lower border of Subscapularis muscle, and courses with the long subscapular nerve to lower angle of scapula.

Branch : —

Dorsalis scapula : given off near origin to dorsum of scapula, passes backwards to the infraspinous fossa through triangular

ARTERIES 75

interval, bounded above and internally by the subscapularis, below by teres major, and externally by the long head of the triceps. In the triangular interval it gives off ventral branches to subscapular fossa, and a descending branch which runs down between the two teres muscles to the angle. Supplies sub- scapularis, latissimus dorsi, teres major, serratus magnus ; anas, supra-scapular and posterior scapular.

Posterior circumflex (3rd part) : arises from back of artery opposite lower border of subscapularis, winds backwards through quadrilateral space, bounded above by the teres minor, below by the teres major, internally by the long head of the triceps, and externally by the neck of the humerus. Supplies deltoid, head of humerus, shoulder-joint, teres minor, and long head of triceps ; anas, acromio - thoracic, anterior circumflex and superior profunda.

Anterior circumflex (3rd part) : arises from outer side of artery, one branch ascends bicipital groove to shoulder-joint, another winds round surgical neck of humerus ; anas, posterior circumflex.

THE BRACHIAL ARTERY.

Extent. — From lower border of teres major to half an inch below bend of elbow, runs along inner borders of coraco- brachialis and biceps, accompanied by venae comites.

Relations. — In front. Integument, fascia, coraco-brachialis, biceps and bicipital fascia, median basilic vein. Crossed by median nerve at insertion of coraco-brachialis.

Behind. Long and inner heads of triceps, musculo-spiral nerve, superior profunda vessels, coraco-brachialis, brachialis anticus.

Inner side. Internal cutaneous nerve to about middle of arm, r.lnar nerve to insertion of coraco-brachialis, median nerve from insertion of coraco-brachialis to elbow.

Outer side. Coraco-brachialis and biceps. Median nerve from origin of artery of insertion of coraco-brachialis.

Branches : —

Superior profunda : arises opposite lower border of teres major, winds backwards and outwards with musculo-spiral nerve in the groove to triceps; gives off anterior branch which pierces external intermuscular septum (anas, radial recurrent) ; and ends as posterior branch behind external condyle ; anas, posterior circumflex, interosseous recurrent, anastomotic. Supplies triceps, anconeus.

Nutrient : arises about middle of humerus, and enters medullary foramen near insertion of coraco-brachialis.

76 THE POCKET ANATOMY

Inferior profuuda: arises opposite insertion of coraco- brachialis, accompanies ulnar nerve, pierces internal inter- muscular septum ; anas, posterior ulnar recurrent and anas- tomotic at elbow.

Anastomotica magna: arises 2 inches above elbow-joint, courses to hollow between olecranon and inner condyle of humerus; anas, inferior profunda, anterior and posterior ulnar recurrent, and a branch across the back of olecranon with superior profunda. Supplies elbow-joint.

Muscular : to coraco-brachialis, biceps, brachialis anticus.

THE RADIAL ARTERY.

Extent. — From bifurcation of the brachial to ending of the deep palmar arch of hand ; accompanied by venae comites.

Relations in the forearm. — In front. Integument, fascia, supinator longus.

Behind. Tendon of biceps, supinator brevis, pronator radii teres, flexores sublimis digitorum et longus pollicis, pronator quadratus, lower end of radius.

Inner side. Pronator radii teres, flexor carpi radialis.

Outer side. Supinator longus tendon, and for middle £rd, radial nerve.

The artery courses along inner border of supinator longus tendon to carpus, winds round carpus beneath extensors of thumb and radial nerve, lying on external lateral ligament of wrist, scaphoid and trapezium, enters palm of hand through the heads of the ist dorsal interosseous muscle, forming deep palmar arch.

Branches : —

Radial recurrent: arises just below elbow, ascends to between brachialis anticus and supinator longus, supplying them and the elbow-joint ; anas, superior profunda.

Muscular : to muscles attached to radial side of forearm.

Superficial volar : arises when the artery is about to wind round carpus, passes between muscles of ball of thumb; anas. with ulnar, completing superficial palmar arch.

Anterior carpal : arises near lower border of pronator quadratus, passes inwards under tendons ; anas, anterior carpal of ulnar.

Posterior carpal : arises beneath extensor tendons of thumb : mas. posterior carpal of ulnar, forming posterior carpal arch , which gives off 2nd and 3rd dorsal interosseous to 3rd and 4th spaces ; and anas, with superior perforating of deep arch, and at lower end of interosseous space gives off inferior per- forating to join palmar digital arteries.

ARTERIES 77

Metaearpal (ist dorsal interosseous) : arises near or with the posterior carpal ; anas, superior perforating of deep arch, digital of superficial arch ; supplies adjoining sides of index and middle fingers.

Dorsalis pollicis (2) : arising near base of ist metacarpal, course along sides of dorsum of thumb.

Dorsalis indicis : courses along radial side of dorsum of index, supplying abductor indicis.

Princeps pollicis : arising as the artery enters palm, courses between ist metacarpal and abductor obliquus pollicis to the base of ist phalanx, where it divides into two terminal branches, which run along the sides of the palmar surface of thumb.

Radialis indicis : arising near the preceding, passes between ist dorsal interosseous and adductor transversus pollicis to outer side of index-finger, sends a branch to superficial palmar arch ; anas, digital of superficial arch.

Deep palmar arch : Extent, from upper end of ist interos- seous space to base of 5th metacarpal. It lies over the bases of the metacarpal bones, and terminates by inosculating with the deep branch of the ulnar.

Branches : —

Recurrent : to front of carpus ; anas, carpal arteries.

Palmar interossei (3) : in the three inner interosseous spaces join digital of superficial arch at cleft of fingers, and an offset from inner branch joins digital branch to inner side of 5th finger.

Superior perforating : pierce three inner dorsal interossei ; anas, dorsal interosseous.

THE ULNAR ARTERY.

Extent. — From bifurcation of brachial to end in superficial palmar arch, coursing along outer side of flexor carpi ulnaris to the palm ; accompanied by venae comites.

Relations in the forearm. — In front. Pronator radii teres, flexor carpi radialis, palmaris longus, flexor sublimis, median nerve in upper half; lower half, overlapped by flexor carpi ulnaris tendon.

Behind, Brachialis anticus, flexor profundus digitorum.

Inner side. Flexor carpi ulnaris, the ulnar nerve in the lower §.

Outer side. Flexor sublimis digitorum.

Lies upon anterior annular ligament at wrist, external to the ulnar nerve and pisiform bone.

78 THE POCKET ANATOMY

Branches : —

Anterior ulnar recurrent : arises near bifurcation of brachial, ascends between brachialis anticus and pronator radii teres, supplying them ; anas, inferior p'rofunda, anas- tomotic.

Posterior ulnar recurrent : arising below the anterior, passes beneath flexor sublimis, ascends behind inner condyle, thence between heads of flexor carpi ulnaris, supplying joint and muscles around; anas, inferior profunda, anastomotic.

Common interosseous : about half an inch long, arising just below radial tubercle, passes to interosseous membrane, there dividing into two terminal branches.

Branches : —

Anterior interosseous : passes down forearm, resting upon anterior surface of interosseous membrane, accompanied by and internal to interosseous branch of median nerve. At upper border of pronator quadratus one branch, the anterior communicating, goes downwards beneath quadratus to anas. with anterior carpal and deep arch : the other piercing in- terosseous membrane descends to back of carpus ; anas, pos- terior interosseous, posterior carpal of radial and ulnar. Supplies nutrient branches to radius and ulna, and branch to median nerve : comes nervi mediani.

Posterior interosseous : passes backwards between oblique ligament and interosseous membrane, and between supinator brevis and extensor ossis metacarpi pollicis, runs down back of forearm, lying internal to posterior interosseous nerve, between superficial and deep muscular layers as far as the wrist ; anas, posterior carpal of radial and ulnar, anterior interosseous.

Branch : —

Posterior interosseous recurrent : given off near origin, passes under anconeus to interval between olecranon and external condyle ; anas, superior profunda, anastomotic.

Muscular : to muscles on ulnar side of forearm.

Anterior carpal : courses beneath tendons of flexor pro- fundus ; anas, anterior carpal of radial.

Posterior carpal : arises just above pisiform, winds back beneath flexor carpi ulnaris tendon, gives branch to inner side of 5th metacarpal, and then passes outwards to anas. with posterior carpal of radial, forming posterior carpal arch (vide Radial Artery).

Superficial palmar arch : continues the ulnar in the hand, lying immediately under palmar fascia and on digital nerves and flexor tendons. It turns outwards a little below the

ARTERIES 79

anterior annular ligament, and, forming an arch with the con- vexity downwards, is directed to the thumb, where the arch becomes completed by joining the superficialis volae, radialis indicis, or princeps pollicis. From the convex side of the arch it gives off four digital branches to supply three inner fingers and inner side of index-finger ; anas, palmar interossei of deep arch, inferior perforating of dorsal interosseous.

The deep branch of ulnar artery or communicating branch is given off at commencement of arch, passes down with the deep branch of ulnar nerve between abductor and short flexor of little finger to complete deep palmar arch.

ARTERIES OF BODY.

THE AORTA.

Large main trunk of systemic arteries, situated partly in thorax and partly in abdomen, commences at left ventricle, arches over root of left lung, descends in front of vertebral column, through diaphragm into abdomen, ending opposite body of 4th lumbar vertebra by bifurcating into two common iliacs. Conveniently divided into three parts: arch of aorta, descending thoracic aorta, abdominal aorta.

ARCH OF AORTA : divided, according to the direction, into ascending and transverse portions. In the concavity of the arch are contained root of left lung, branching of pulmonary artery with ductus arteriosus, cardiac plexuses, left recurrent laryngeal nerve, oesophagus and thoracic duct.

Ascending part : Extent and Course.— Two inches in length. From base of left ventricle, opposite lower border of 3rd left costal cartilage, passing behind pulmonary artery, upwards and to the right, crossing the posterior surface of the sternum obliquely, and extending as high as superior border of 2nd right costal cartilage. At its root it presents three bulgings, the sinuses of Valsalva, and along the right side is a dilatation, the great sinus of the aorta.

Relations. — Is contained nearly completely in pericardium.

In Front. Behind. Right Side. Left Sidt.

Pulmonary artery. Left auricle. Superior cava. Pulmonary ar

Right auricular ap- Right pulmonary Right auricle. tery.

pendix. vessels.

Pericardium. Root of right lung.

Right lung and

pleura. Sternum.

So

THE POCKET ANATOMY

Branches. — Right and left coronary arteries distributed to heart (vide Heart).

Transverse part, which runs much more from before back- wards than from right to left, so that relations in front are also to the left, and those behind to the right, commences at upper border of 2nd right costal cartilage, arching backwards over root of left lung, as far as inferior border of left side of body of 4th dorsal vertebra.

Relations.
In Front and A, to Left. Abave'	Below.	Behind and to Right.
Manubrium. Left innominate	Bifurcation of pul-	Trachea.
Thymus. vein.	monary artery.	Deep cardiac
I .eft pleura and	Ductus arteriosus.	plexus.
lung.	Left bronchus.	(Esophagus.
Left phrenic \ Inferior car- J	Left recurrent laryngeal nerve.	Thoracic duct. Left recurrent
diac of left I j,		laryngeal nerve.
vagus 1 § Superior car- f <u
diac of left fc
sympathetic 1
Left vagus /
Left superior in-
tercostal vein.

Branches : —

Innominate (i| to 2 inches long) : arises at commencement of transverse part, ascends to right beneath sternum, dividing opposite right sterno-clavicular articulation into right common carotid and right subclavian arteries (vide Arteries of Head and Neck, pp. 59 and 64).

Relations of the Innominate. — Lies behind manubrium and origins of right sterno-hyoid and sterno-thyroid muscles, thymus gland and left innominate and right inferior thyroid veins. Trachea at first behind, but above to left side, where artery lies on pleura. On the right side lie the right innomi- nate vein and right phrenic nerve. On the left side, below is the left common carotid, above the trachea. The innominate occasionally gives off a branch, the arteria thyroidea ima, which passes in front of trachea to thyroid gland.

Left common carotid (vide Arteries of Head and Neck, p. 64).

THE DESCENDING THORACIC AORTA.

Extent. — From lower border of 4th dorsal vertebra (left side) to aortic opening in front of body of i2th dorsal ver- tebra.

ARTERIES 8 1

Course and Relations. — Lies in posterior mediastinum ; is at first to left of bodies of vertebrae, but afterwards lies in front of them.

In front. Root of left lung, pericardium and diaphragm, crossed by oesophagus at lower end.

Behind. Bodies of vertebrae and venae azygoi minores, superior and inferior.

Left side. Left lung and pleura, oesophagus below.

Right side. (Esophagus above, thoracic duct, and vena azygos major : right lung and pleura.

Branches : —

Bronchial : supply structure of lungs. For the left lung two branches come off from front of aorta (superior and inferior). The artery supplying right lung arises either with or from superior left branch, or from first right aortic intercostal.

Pericardial : small twigs to posterior surface of pericar- dium.

(Esophageal (4 or 5) : from front of aorta, running obliquely downwards to supply oesophagus ; anas, with one another, inferior thyroid and coronary of stomach.

Posterior mediastinal : supply glands, etc., of posterior mediastinum.

Intercostal (9 pairs) : arise from posterior part of aorta, run transversely outwards on bodies of vertebrae, and behind pleura to intercostal spaces. The right ones, crossing over front of spine, supply the bodies of vertebrae, and pass behind oesophagus, thoracic duct, and azygos veins. The arteries of both sides are crossed by sympathetic chain and its splanch- nic branches. On reaching intercostal spaces, they divide into anterior and posterior branches ; the anterior branch crosses the space obliquely upwards so as to get to lower border of the upper rib near the angle : at first it lies between external intercostal and fascia, subsequently between two intercostal muscles ; anas, anterior intercostal of internal mammary, thoracic branches of axillary. Above the artery is a companion vein, and below the intercostal nerve. A branch, the collateral intercostal, is given off near the angle of the rib, which runs along the upper border of the lower rib ; anas, anterior intercostal. Branches accompany the lateral cutaneous nerves of the thorax from the main trunks of the intercostals. The three lower branches pass forwards between muscles of abdominal wall ; anas, epigastric and lumbar.

The posterior branch passes backwards between vertebra and superior costo- transverse ligament, sending inwards, spinal branch through intervertebral foramen to cord, membranes

6

82 THE POCKET ANATOMY

and body of vertebra, and backwards, muscular branch which divides into inner and outer branches to muscles of back.

(The ist and 2nd intercostal arteries come from the sub- clavian trunk, vide p. 64).

ABDOMINAL AORTA.

Extent. — From last dorsal vertebra to the left side of body of 4th lumbar vertebra, there dividing into common iliacs.

Course and Relations. — Enters abdomen between pillars of diaphragm, occupying middle line of spine, but near its bifur- cations inclines to left side.

In front, from above down. Small omentum, stomach, solar plexus, pancreas, splenic vein, left renal vein, 3rd part of duodenum, root of mesentery, coils of small intestine, aortic plexus and peritoneum. It touches the pancreas and duodenum without any intervening peritoneum.

Behind. Bodies of upper 4 lumbar vertebrae, left lumbar veins, receptaculum chyli and thoracic duct. Embraced by crura of diaphragm above.

On right side. Vena cava inferior, thoracic duct, vena azygos major, and right semilunar ganglion.

On left side. Left sernilunar ganglion, and left cord of sympathetic.

Branches : —

Inferior phrenic (2): arising close together immediately below diaphragm, pass on its under surface across crura, the left one passing behind oesophagus, the right one behind inferior vena cava.

Branches : —

Internal : to fore-part of diaphragm ; anas, fellow, and superior and musculo-phrenic of internal mammary.

External : to outer side of muscle ; anas, musculo-phrenic, lower intercostals.

Superior capsular : to supra-renal body.

Cceliac axis : arises between pillars of diaphragm, just above pancreas, £ incn I°ng5 surrounded by solar plexus ; divides into three visceral branches.

Branches : —

CORONARY OF STOMACH : smallest of three branches, directed upwards and to left side behind lesser sac of peritoneum to car- diac end of stomach ; gives off a few cesophageal branches, then turns to right along lesser curvature, giving branches on each side to viscus, finally anastomoses with pyloric of hepatic.

HEPATIC : directed (to right) forwards and upwards between, layers of small omentum, and anterior to foramen of Winslow,.

ARTERIES 83

to transverse fissure of liver, lying to left of common bile-duct and in front of vena portae ; at transverse fissure it divides into right and left hepatic, supplying corresponding lobes of the liver.

Branches : —

Pyloric : extends on leser curvature of stomach running from right to left ; anas, coronary.

G astro- duodenal : passes behind ist part of dubdenum, divides at lower border into the two following branches :

Right gastro-epiploic : runs along great curvature of stomach from right to left, anas, with left gastro-epiploic of splenic, gives off branches upwards to viscus and downwards to 'omen turn.

Superior Pancreatico-duodenal : runs between the 2nd part of duodenum and the pancreas down to anas, with inferior pancreatico-duodenal of superior mesenteric.

Right Hepatic, to right lobe of liver, giving off Cystic: to supply gall-bladder.

Left Hepatic, to left lobe, giving off branch to Spigelian lobe.

SPLENIC : directed horizontally to left along upper border of pancreas, crossing the left kidney ; reaches spleen by passing between two layers of lieno-renal ligament, and then gastric branches reach stomach between layers of gastro - splenic omentum : supplies spleen and partly stomach and pancreas. Very tortuous; divides near spleen into several terminal branches which enter hilum of that viscus.

Branches : —

Pancreatic : given off as artery runs along pancreas ; one of them (arteria pancreatica magna) accompanies the duct, running from left to right.

Left gastro-epiploic : directed to right side between layers of great omentum, along great curvature of stomach. Anas- tomoses with right gastro-epiploic of hepatic.

Gastric branches (vasa brevia] (5 or 6) : extend to left ex- tremity of stomach to supply its coats.

Supra-renal or middle capsular (2) arises a little below coeliac axis ; each runs transversely outwards over crus of diaphragm to supra-renal body ; anas, superior capsular of phrenic and inferior capsular of renal.

Superior mesenteric : arises £ inch below coeliac axis, passes forwards between pancreas and upper border of 3rd part of duodenum, crosses duodenum, and directed downwards and to the right between the layers of the mesentery, termi- nates in offsets to small intestine, caecum and colon.

Relations. — In front and above. Pancreas and splenic vein.

6-a

84 THE POCKET ANATOMY

Behind. Duodenum, 3rd part, and left renal vein. Sur- rounded by mesenteric plexus of nerves and accompanied by its vein, which lies anterior and to right.

Branches : —

Inferior Pancreatico- duodenal : directed from left to right along concave border of 3rd part of duodenum ; anas, superior pancreatico-duodenal.

Vasa intestini tennis : to supply jejunum and ileum, twelve or fifteen in number ; spring from left convex side of artery ; about 2 inches from origin they bifurcate, each division uniting with a neighbouring branch to form an arch, from which branches issue ; these divide and communicate in the same way four or five times, the resultant branches proceeding directly to intestine.

Ileo-colic: from right side of artery down to caecum, branch- ing to supply head of colon. A descending branch to lower part of ileum. An ascending to ascending colon and anas. with right colic.

Right colic (often a branch of ileo-colic) : from right side of trunk to middle of ascending colon, ascending branch anas. middle colic, descending branch anas, ileo-colic.

Middle colic : passing forward in transverse meso-colon from upper part of right side of artery, supplies transverse colon ; right branch anas, right colic ; left branch anas, on descending colon, with left colic of inferior mesenteric.

Renal (2) : one from each side arising £ inch below superior mesenteric, the right a little lower than the left one. Pass outwards to supply kidneys, the right one passing behind vena cava. Each divides near viscus into four or five branches, which enter it between vein and ureter. Is ac- companied by plexus of nerves, supplies branches to supra- renal body (inferior capsular], ureter and fat around.

Spermatic : two small but very long arteries ; arise just below renal, directed downwards and outwards behind peri- toneum over psoas, crossing ureter and external iliac artery (the right one crosses also the inferior vena cava) to internal abdominal ring, thence accompanied by spermatic vein, spermatic plexus, and vas deferens, it passes along inguinal canal, and out of the external ring to the scrotum, where it divides into branches which enter the posterior surface of the testis ; anas, artery of vas deferens and cremasteric.

In the female the artery is termed ovarian, and runs between layers of broad ligament of uterus, to ovary and round ligament.

Inferior mesenteric : arises on left side of aorta, about

ARTERIES 85

i£ inches above bifurcation. Lies at first on left side of aorta, then crosses over left psoas, left common iliac and ureter, to back of rectum ; supplies descending, iliac and pelvic parts of colon and rectum.

Branches : —

Left colic : directed upwards in front of left kidney, ascending branch anas, middle colic; descending branch supplies descend- ing colon ; anas, sigmoid and superior haemorrhoidal.

Sigmoid : to iliac and pelvic colon ; anas, left colic and superior haemorrhoidal.

Superior h&morrhoidal : continuation of inferior mesenteric trunk, passes behind rectum and divides in meso-rectum into two branches, which pass down, one on either side, to about 6 inches from anus, where they subdivide to supply pelvic colon and rectum ; anas, sigmoid, middle and inferior haemorrhoidals.

Lumbar (5 pairs] : arise from back of aorta, pass outwards, resting on body of corresponding vertebrA underneath sym- pathetic and psoas ; the two upper pairs under crura of diaphragm ; the right ones also under vena cava. Divide near transverse processes into : —

Abdominal : coursing outwards beneath quadratus (the first pair cross quadratus), to end between muscles of abdominal wall ; anas, deep epigastric, internal mammary, intercostals, ilio-lumbar, circumflex iliac.

Dorsal : accompanies posterior primary branch of nerve, gives off spinal branch to supply meninges and cord ; anas. intercostal.

Middle sacral : a small branch given off just at bifurcation courses over 5th lumbar vertebra and middle of sacrum to coccyx behind the left common iliac vein, anas, lateral sacral.

THE COMMON ILIAC ARTERY.

Extent. — From bifurcation of aorta, on body of 4th lumbar vertebra, to opposite lumbo-sacral articulation, there dividing into external and internal iliac. About 2 inches long.

Relations. — In front. Peritoneum, small intestines, ureter, branches of sympathetic.

Differences between right and left artery. — The right one is the longer, the aorta being on the left side of spine ; on right side are inferior vena cava and right psoas. Companion vein at first behind, but to the right at upper part ; left common iliac vein behind. The left one is crossed anteriorly by inferior mesenteric artery, the companion vein being below and internal.

86 THE POCKET ANATOMY

Collateral branches. — None named, supplies peritoneum, psoas, ureters, and lymphatics. One of the renal, lumbar or ilio-lumbar vessels may come off from it.

THE INTERNAL ILIAC ARTERY.

Extent. — From bifurcation of common iliac opposite lumbo- sacral articulation to great sacro-sciatic notch, there dividing into anterior and posterior trunks. i£ inches long.

Relations : in front peritoneum, crossed by ureter, ileum on right, pelvic colon on left : behind on inner border of psoas, internal iliac vein, lumbo-sacral cord and sacrum. Note that this artery lies inside parietal layer of pelvic fascia, which is pierced by all the parietal branches, e.g., sciatic, gluteal.

From the extremity a partly obliterated artery, the hypo- gastric, extends forwards to "side of bladder, between the layers of posterior^false ligament. In the foetus this vessel is nearly as large as the common iliac, ascends the wall of abdomen to umbilicus, passing thence to placenta ; after birth the vessel becomes obliterated except i^ inches at com- mencement.

Branches from Anterior Trunk :

Superior vesical : is the unobliterated part of hypogastric, extending from sacro-sciatic notch in posterior false ligament to side of bladder.

Branches supplied to side and upper part of bladder, and to ureter.

Artery of vas defer ens : accompanies duct to anas, with sper- matic.

Middle vesical : supplies side of bladder.

Inferior vesical : supplies base of bladder, side of prostate and vesiculae seminales in the male.

Middle hsemorrhoidal : supplies lower part of rectum and in the female to vagina. May come off from inferior vesical ; anas, superior haemorrhoidal of inferior mesenteric, inferior haemorrhoidal of internal pudic.

[Uterine : down to neck of uterus, passes inwards between layers of broad ligament to supply body of viscus, where it crosses the ureter superiorly and then divides into a large ascending branch to fundus and ovary, anas, ovarian ; and small descending branch to vagina, anas, vaginal.

Vaginal : corresponds to inferior vesical in male, supplies vagina, fundus of bladder, and lower part of rectum.]

Obturator : directed to groove in upper part of thyroid foramen, passing out of pelvis and dividing into two branches

ARTERIES 87

at upper border of obturator externus. In pelvis it is placed between pelvic fascia and peritoneum, and just below obtu- rator nerve. It lies beneath the horizontal pubic ramus with companion vein and nerve in canal, formed above by bone and below by obturator membrane.

Branches within pelvis : —

Iliac : enters iliac fossa, supplies iliacus and bone ; anas. ilio-lumbar.

Pubic : ascends posterior surface of pubis ; anas, opposite fellow, deep epigastric.

Branches outside pelvis : —

Internal terminal : curves inwards beneath obturator ex- ternus, supplies obturators, gracilis, and adductors; anas. internal circumflex, and external branch of obturator.

External terminal : passes downwards and outwards beneath obturator externus to ischial tuberosity, supplies obturators, hamstrings and hip-joint ; anas, sciatic and internal branch of obturator.

Internal Pudic : —

In the male. Proceeds out of pelvis by great sacro-sciatic notch below pyriformis, winds round ischial spine, re-enters pelvis by small notch, passes within the obturator fascia on inner side of tuber ischii, courses along pubic arch, perforates the two layers of triangular ligament very obliquely, dividing on triangular ligament into dorsal of penis and artery of corpus cavernosum.

Relations. — In the pelvis, lies to outer side of rectum, in front of pyriformis and sacral plexus. In gluteal region is seen under gluteus maximus, on ischial spine, below pyri- formis, external to pudic nerve, and internal to nerve to obturator internus. Thence, in company with vein and nerve, it is on external wall of ischio-rectal fossa, and internal to obturator internus. Beneath triangular ligament crossed by transverse perineal muscle.

Branches : —

Inferior hamorrhoidal : arises just inside tuber ischii, piercing Alcock's canal, crosses transversely ischio-rectal fossa, sup- plies sphincter and levator ani ; anas, middle hsemorrh'oidal and opposite fellow.

Superficial perineal : arising half-way in ischio-rectal fossa, runs parallel to pubic arch, crossing transversus perinei, lying deep to Colics' fascia, between erector penis and accelerator urinae, supplying them, together with scrotum ; anas, super- ficial pudic of femoral.

Transverse pciincal : arises from superficial perineal or from

88 THE POCKET ANATOMY

trunk near it, courses transversely inwards, supplying integu- ments, etc.

Artery of bulb : arises near base of triangular ligament, as internal pudic artery lies between the two layers of triangular fascia, it then pierces anterior layer, reaching bulb ^ inch from base. Supplies a branch to Cowper's gland.

Artery of corpus cavernosum : lies between crus penis and pubic ramus. Enters crus and is distributed to corpus caver- nosum.

Dorsal artery of penis : lies between crus and pubic ramus, through suspensory ligament, along dorsum of penis having the median dorsal vein inside and the nerve outside. It ends in the glans and prepuce.

In the female : the vessel is smaller and has similar course to that in male ; the superficial perineal supplies labia pudendi The artery of bulb supplies bulbus vestibuli. The terminal dorsal and corpus cavernosum arteries supply clitoris, being named dorsalis and profunda clitoridis respectively.

Sciatic : terminal branch of anterior trunk (vide Arteries of Lower Limb, p. 89).

Branches from Posterior Trunk : —

Gluteal : vide Arteries of Lower Limb (p. 90).

Ilio-lumbar : passes upwards, backwards, and outwards beneath psoas and obturator nerve, but anterior to lumbo- sacral cord ; divides in iliac fossa into ascending or lumbar branch, supplying psoas, quadratus lumborum, and giving a spinal branch through foramen between 5th lumbar vertebra and the sacrum. Transverse or iliac ramifies in iliacus, sup- plies bone ; anas, lumbar, deep circumflex iliac.

Lateral sacral (2) : Superior, the larger of the two dis- tributed to upper part of sacrum, the Inferior to lower part of sacrum and coccyx ; anas, middle sacral and opposite artery.

Branches (dorsal) are given off, which enter anterior sacral foramina for distribution on back of sacrum.

THE EXTERNAL ILIAC ARTERY.

Extent. — From bifurcation of common iliac opposite lumbo- sacral articulation to lower border of Poupart's ligament.

Course. — Lower § of line from f inch below and little to left of umbilicus, to point of Poupart's ligament midway between symphysis pubis and anterior superior iliac spine.

Relations.— Covered by peritoneum and sub-peritoneal fat, crossed by ureter and deep circumflex iliac vein, on the right by ileum, left by iliac colon. The spermatic vessels and genito-crural nerve lie on it for a short distance.

ARTERIES 89

To outer side, psoas, except at termination, when it is behind. Inner side, vas deferens and lymphatic glands. The left vein is internal to its artery. The right one is at first internal, but at upper part beneath its artery.

Branches : —

Deep epigastric : from fore part of artery, just above Poupart's ligament, down to ligament, then upwards and inwards between peritoneum and fascia transversalis, being crossed externally by vas deferens near internal abdominal ring; pierces transversalis fascia, and then passes upwards behind rectus to enter sheath under semilunar fold of Douglas ; terminates between rectus abdominis and sheath in anas- tomoses with superior epigastric branch of internal mammary and lower intercostals.

Branches :

Cremasteric : accompanies vas deferens, supplying cremaster ; anas, spermatic, artery of vas deferens.

Pubic : ramifies behind pubis ; anas, pubic of obturator.

Muscular : to rectus ; anas, superficial epigastric.

Deep circumflex iliac: from outer side of artery, near Poupart's ligament, directed to anterior superior iliac spine, then on iliac crest, gradually piercing transversalis fascia and muscle and supplying iliacus, etc. ; anas, ilio-lumbar.

ARTERIES OF LOWER LIMB.

THE SCIATIC ARTERY.

Largest branch of internal iliac, except gluteal, passes out through lower part of great sacro-sciatic foramen, between pyriformis and superior gemellus, in company with great sciatic nerve and internal pudic artery, outside the pelvis it lies between the tuber ischii and great trochanter, under gluteus maximus, below which it ends in cutaneous branches to thigh.

Branches : —

Within the pelvis. Muscular to pyriformis, coccygeus and levator ani.

Outside pelvis : —

Coccygeal branch : pierces great sacro-sciatic ligament, in- clined inwards, supplies gluteus maximus, integument, etc.

Comes nervi ischiadici : accompanies great sciatic nerve, finally enters the substance of it.

Muscular : branches to gluteus maximus and external rotators of thigh ; anas, gluteal, internal^ circumflex.

go THE POCKET ANATOMY

Anastomotic : (i) to pit of great trochanter (digital anas- tomosis], supplies external rotators ; anas, gluteal, ascending of internal circumflex, and (2) to crucial anastomosis; anas. first perforating, internal and external circumflex.

Articular : to capsule of hip-joint.

THE GLUTEAL ARTERY.

Largest branch of internal iliac, passes outwards between lumbo-sacral cord and ist sacral nerve, escapes from pelvis above pyriformis, divides immediately into superficial and deep branches.

Superficial branch : runs between the two larger glutei, sup- plying gluteus maximus ; anas, sciatic and internal circumflex.

Deep branch : goes between two smaller glutei, subdivides into two : —

Superior division : goes to anterior superior iliac spine ; anas. circumflex iliacs, ascending branches of external circumflex.

Inferior division : supplies gluteal muscles, and descends to great trochanter ; anas, external circumflex.

Nutrient branch : enters hip-bone just as artery emerges from pelvis.

THE FEMORAL ARTERY.

Extent. — From Poupart's ligament to the opening in the adductor magnus.

Course. — Thigh being abducted and rotated out, a line drawn from point midway between symphysis pubis and anterior superior iliac spine to most prominent part of in- ternal condyle of femur, will in upper §rd give course.

Relations. — Superficial in upper £rd, being contained in Scarpa's triangle, -more deeply placed in middle Jrd (Hunter's canal). In first i^ inches is enclosed in femoral sheath.

In front. Skin, superficial and deep fascia, internal cutane- ous branch of anterior crural nerve, sartorius, long saphen- ous nerve, aponeurotic arch over Hunter's canal.

Behind. Psoas, prcfunda vessels, pectineus, adductor longus, femoral vein (at lower part of Scarpa's triangle, and in Hunter's canal), tendon of adductor magnus.

Inner side. Femoral vein (in Scarpa's space), adductor longus.

Outer side. Sartorius (in Scarpa's space), vastus internus, femoral vein gets to outer side near ending.

Branches : —

Superficial epigastric : arises $ inch below Poupart's liga- ment, ascends through the saphenous opening to abdominal

ARTERIES 91

wall, as high as umbilicus, in the fascia, anas, fellow of opposite side, superficial branches of deep epigastric.

Superficial circnmflex iliac : arises near preceding, runs outwards to iliac crest, supplies glands, fasciae, and integu- ment, psoas and iliacus; anas, deep circumflex iliac, gluteal, external circumflex.

Superior external pudic : arises from inner side of artery ^ inch below Poupart's ligament, pierces cribriform fascia of saphenous opening, runs upwards to pubic spine, crosses ex- ternal ring and spermatic cord, supplying integument of lower part of abdomen and external organs of generation ; anas, in- ternal pudic.

Deep external pudic : arises either separately or from a common trunk with the preceding, lies on pectineus, covered by fascia lata, which it pierces, and is distributed to scrotum in male and labium in female ; anas, superficial perineal.

Profunda femoris : arises from outer and back part of artery, i or 2 inches below Poupart's ligament, and passing outwards and downwards rests in Scarpa's triangle upon the iliacus, then curving inwards, crosses psoas and pectineus behind the femoral artery, from which it is separated by the deep femoral vein , and lies subsequently upon adductores brevis and magnus, having the longus superficial to it. It ends in the lower third of thigh in a branch which perforates adductor magnus.

Brandies : —

External circumflex : arises from the outer side of the pro- funda (sometimes from the femoral trunk), coursing under rectus and sartorius outwards through the divisions of the anterior crural nerve, dividing into :

(a) Transverse branches, piercing vastus externus just below great trochanter; anas, below trochanter with internal circum- flex, first perforating branch of profunda, and sciatic, (crucial anastomosis).

(b) Ascending pass beneath sartorius, rectus, and tensor fasciae femoris ; anas, with terminal of gluteal and deep circumflex iliac.

(c) Descending branches are distributed to the extensors of the thigh ; anas, with superior articular arteries, a small offset passing, with the articular nerve from the nerve to vastus ex- ternus, to the knee-joint.

Internal circumflex : arises from the internal and back part of profunda, courses backwards between psoas and pectineus, and then below capsule of hip between obturator externus and adductor brevis, dividing at the small trochanter into two branches, one ascending deep to quadratus femoris to

92 THE POCKET ANATOMY

the digital fossa of the great trochanter ; anas, sciatic and gluteal ; the other passes to the hamstrings, appears between adjacent borders of quadratus femoris and adductor magnus, gives off muscular branch at upper border of adductor brevis, which divides into superficial and deep branches to upper adductor muscles, the trunk of the artery then passes out- wards and backwards ; anas, first perforating, sciatic, and external circumflex (crucial anastomosis}. An articular branch enters the joint through the notch in acetabulum.

Perforating branches : four in number, reach the back of thigh by perforating the adductor magnus, and end in the back of thigh : —

First, begins opposite lower border of pectineus, perforates adductores brevis and magnus, distributed to biceps and gluteus maximus ; anas, sciatic, internal and external circumflex.

Second, comes off opposite middle of short adductor, per- forating it and the magnus, distributed to hamstrings ; a nutrient artery (passing upwards) is given off; anas, other perforating branches.

Third, arises at the lower border of adductor brevis, per- forates magnus, as the second, ending in the biceps.

Fourth, or terminal branch, pierces adductor magnus near opening for femoral vessels, supplies short head of biceps ; anas, popliteal and lower perforating.

Muscular Branches : two to seven in number, supplying sartorius and vastus internus.

Anastomotic branch : arises at the termination of the femoral, and courses in the line of the femoral to the internal condyle.

Branches :—

Deep branch, descends inner side of knee ; anas, superior internal articular ; gives off external branch, crosses the femur, supplying branches to knee-joint ; anas, superior external articular, forming an arch above patella.

Superficial branch, accompanies long saphenous nerve to integument; anas, inferior internal articular.

THE POPLITEAL ARTERY.

Extent. — From the opening in the adductor magnus to lower border of popliteus, dividing into anterior and posterior tibial.

Course. — Upper part inclines from inner side of femur to middle of intercondylar space, thence occupying middle line of popliteal space.

ARTERIES 9,

Relations.— The part of artery in the popliteal space is partly covered by the semimembranosus, and below it is covered by the gastrocnemius and plantaris. It rests upon the femur, posterior ligament of knee-joint and popliteus. The vein lies to the outer side in the upper part, but crosses to the inner side near the termination. Superficial and slightly external to the artery is the internal popliteal nerve, in the upper part, but below it crosses to inner side. A small articular branch of the obturator nerve courses upon the artery.

Branches : —

Muscular : Superior set (3 or 4) : to lower end of hamstrings ; anas, perforating of profunda, superior articular.

Inferior set or sural (2) : arise from the posterior part of artery opposite knee-joint, supply both heads of gastroc- nemius, plantaris and soleus.

Superficial : accompanies external saphenous nerve to end in integuments.

Superior articular : Internal. Arises just above condyles of femur, courses transversely inwards beneath semimembranosus and tendon of adductor magnus to front of knee, ending in vastus intern us and joint ; anas, anastomotic and superior external articular.

External. Winds beneath biceps, perforates intermuscular septum ; anas, descending branch of external circumflex, ex- ternal of anastomotic and superior internal articular, forming an arch, inferior external articular; supplies joint by super- ficial and deep branches.

Inferior articular: Internal. Passes down on internal tuberosity of tibia, beneath inner head of gastrocnemius and internal lateral ligament ; anas, opposite artery, superior in- ternal articular, anterior tibial recurrent.

External. Courses outwards under outer head of gastroc- nemius, plantaris and external lateral ligament ; anas, in front with other articular branches, anterior tibial recurrent.

Azygos articular : arises opposite flexure of joint, pierces posterior ligament, supplying crucial ligaments and other structures in the joint.

THE ANTERIOR TIBIAL ARTERY.

Extent. — From division of popliteal artery at lower border of popliteus, to bend of ankle, where it becomes dorsalis pedis.

Course. — At first directed outwards and forwards, through two heads of origin of tibialis posticus, to reach anterior sur- face of interosseous membrane; thence a line drawn from

94 THE POCKET ANATOMY

inner side of head of fibula to midway between the two malleoli will mark its course.

Relations. — Tibialis anticus to inner side, the extensor com- munis digitorum above, and the extensor proprius hallucis below upon its outer side, covered below by annular ligament and crossed by extensor proprius hallucis tendon, rests below upon the anterior surface of the tibia. It is accompanied by two venae comites. Anterior tibial nerve lies at first on outer side, then becomes superficial, and below is on the outer side.

Branches : —

Posterior Tibial Recurrent : passes upwards deep to popli- teus to back of knee.

Superior Fibular: passes over neck of fibula, through soleus, to peroneus longus.

Anterior Tibial Recurrent : arises as artery reaches anterior surface of interosseous membrane, passes in tibialis anticus to external and anterior surfaces of knee-joint ; anas, articular of popliteal.

Malleolar : Two in number, arise just above ankle-joint, supplying it.

Internal. Passes beneath extensor longus hallucis and tibialis anticus tendons to inner malleolus ; anas, branches of posterior tibial.

External. Passes outwards beneath extensor longus digi- torum and peroneus tertius ; anas, anterior peroneal, tarsal of dorsalis pedis.

Muscular : to surrounding muscles.

DORSAL ARTERY OF FOOT.

Extent. — From bend of ankle to posterior part of ist inter- osseous space, ending by anastomosing with external plantar artery to form plantar arch after it has entered sole between heads of origin of ist dorsal interosseous muscle.

Relations. — Lies between tendons of extensor proprius hallucis and extensor longus digitorum ; near termination it is crossed by innermost tendon of extensor brevis digitorum. Bound down by fascia lying on astragalus, scaphoid, and middle cuneiform. Accompanied by two venae comites. Anterior tibial nerve lies to outer side.

branches : —

Tarsal : arises as artery crosses scaphoid, courses forwards and outwards beneath extensor brevis digitorum, supplying it, then backwards to cuboid; anas, external plantar, meta- tarsal, external malleolar, anterior peroneal.

ARTERIES 95

Metatarsal : arises near bases of metatarsals, directed out- wards in an arched direction, beneath short extensor of toes to outer side of foot, near bases of xnetatarsal. bones ; anas. tarsal, external plantar. From the convexity of arch proceed three dorsal interosseous branches to three outer metatarsal spaces. They supply the interossei and divide at cleft of toes into digital branches ; the most external one supplies also outer side of little toe. Each interosseous artery com- municates at the cleft of the toes with the plantar digitals by* an anterior perforating branch, and at the back of the inter- osseous space with the plantar arch by a posterior perforating branch.

The 1st dorsal interosseous artery : arises as dorsalis pedis is about to dip down into sole. It lies over dorsum of ist interosseous space, and divides at cleft to supply contiguous sides of ist and 2nd toes, having previously given off a branch to inner side of ist toe.

Plantar digital, or arteria magna hallucis : arises in sole, passes forwards in ist interosseous space to cleft, where it divides into two branches for contiguous sides of ist and 2nd toes, having previously given off a branch of inner side of great toe.

THE POSTERIOR TIBIAL ARTERY.

Extent. — From lower border of popliteus to lower edge of internal annular ligament of ankle, there dividing into internal and external plantar, at a spot midway between internal malleolus and heel.

Course. — At first midway between tibia and fibula, after- wards approaches tibia and lies on it.

Relations. — Upper frds covered by gastrocnemius and soleus. Lower £rd superficial between inner border of Tendo Achillis and inner border of tibia. Posterior tibial nerve is at first on inner side, but about i inch down crosses posteriorly to reach outer side. Has vends comites, and lies •on tibialis posticus, flexor longus digitorum, tibia, and back of ankle-joint.

Relations of artery at inner malleolus, from within outwards. Tibialis posticus and flexor longus digitorum tendons, vein, •artery, vein, nerve, flexor longus hallucis tendon.

Branches : —

Peroneal : arises i inch from popliteus, courses obliquely to fibula, then along inner border of that bone, between origins •of tibialis posticus and flexor longus hallucis, to lower part of interosseous membrane, where it gives off anterior peroneal,

96 THE POCKET ANATOMY

and is continued as posterior peroneal over lower tibio-fibular articulation to outer side of external malleolus, where it ends by anas, with external plantar and tarsal. Covered in upper part by soleus and deep fascia, then by flexor longus hallucis. Beyond the malleolus it is superficial.

Branches of peroneal :

Muscular ; to soleus, tibialis posticus, flexor longus hallucis, and peronei.

Nutrient : to the fibula, passes downwards.

Anterior peroneal: arises about 2 inches above external malleolus, pierces or passes below interosseous membrane, and under cover of peroneus tertius reaches front of outer malleolus and tarsus, supplying ankle-joint ; anas, external rnalleolar, tarsal of dorsalis pedis, and terminal of peroneal.

Communicating : to join communicating of posterior tibial.

Muscular : to soleus, and deep muscles of back of leg.

Nutrient : to tibia, arises near origin of posterior tibial, largest of kind in body, passes downwards.

Communicating : arises 2 inches above inner malleolus, courses beneath flexor longus hallucis ; anas, communicating of peroneal.

Internal calcaneal : arises near termination, pierces internal annular ligament with internal calcaneal nerve, to supply integument, fat of heel, and muscles on inner side of foot.

INTERNAL PLANTAR.

The smaller branch of the posterior tibial, directed for- wards along inner border of foot as far as base of ist meta- tarsal bone, thence along inner side of great toe to anastomose with inner digital branch, is covered at first by abductor hallucis, and subsequently becomes more superficial by lying between that muscle and the flexor brevis digitorum ; it is accompanied by internal plantar nerve.

Branches : —

Digital, to clefts between four outer toes, joining digital branches from plantar arch.

Cutaneous, to inner side and sole of foot.

Muscular.

EXTERNAL PLANTAR.

From inner part of foot, beneath abductor hallucis, it runs with external plantar nerve, between flexor brevis digitorum and flexor accessorius, to base of fifth metatarsal ; thence it

VEINS 97

passes inwards, resting on the interosseous muscles and deep to flexor tendons and lumbricals to the back part of the ist interosseous space, and anastomoses with dorsalis pedis, completing plantar arch.

The plantar arch is placed across the tarsal end of the meta- tarsus, and is accompanied by the deep branch of the external plantar nerve.

Branches from the Plantar Arch : —

Recurrent : small branches passing back to tarsal joints ; anas, branches of internal plantar.

Posterior perforating (3) : ascend to dorsum of foot through posterior part of three outermost interosseous spaces ; anas. interosseous of metatarsal.

Digital (4) : supply both sides of three outer toes and outer half of 2nd ; inner three bifurcate at the cleft of toes ; give off at point of division, anterior perforating to anas, with inter- osseous arteries of dorsum.

THE VEINS.

VEINS OF THE HEAD AND NECK.

Cerebral : noted for their thin coats, absence of muscular tissue and valves.

Superior (10 to 12 on each side) : lodged chiefly in sulci on cerebral surface, pass forwards and inwards to superior longi- tudinal sinus.

Anterior inferior: from under surface of anterior lobes; ter- minate in cavernous sinus.

Inferior lateral (3 to 5) : terminate in lateral sinus.

Inferior median : from posterior lobe, etc., to straight sinus behind venae Galeni.

Venae Galeni (2, one from right, one from left lateral ven- tricle) : formed by vena corporis striati and vena choroidea ; pass backwards out of transverse fissure to unite and end in straight sinus.

Cerebellar : superior, inferior, and lateral sets ; the ist open into straight, the 2nd into lateral, the 3rd into superior petrosal sinuses.

Sinuses (17 in number): Superior longitudinal: begins at crista Galli, where it may communicate through foramen

7

98 THE POCKET ANATOMY

caecum with nasal veins, runs back in upper border of falx cerebri to torcular Herophili, usually joining right lateral sinus ; receives superior cerebral, parietal and emissary veins. Intersected by fibrous bands, the chordae Willisii ; the lumen is triangular, and on either side lie the Pacchionian bodies.

Inferior longitudinal : along posterior | of free margin of falx cerebri to straight sinus.

Straight : is placed at junction of tentorium and falx cerebri, goes to torcular Herophili, ending usually in left lateral sinus ; receives "inferior longitudinal sinus, vena magna Galeni, inferior median cerebral, and superior cerebellar veins.

Lateral (2) : from torcular Herophili to foramen lacerum pos- terius, empties into internal jugular vein, each receives superior petrosal and occipital sinuses, and mastoid vein : the right also receives the superior longitudinal and the left the straight sinus. Joins inferior petrosal sinus to form internal jugular vein below jugular foramen.

Occipital (2) : smallest ; from posterior margin of foramen magnum to torcular Herophili.

Cavernous (2) : by side of sella turcica, passes from sphe- noidal fissure to apex of petrous part of temporal. Receives ophthalmic veins which connect the angular vein with this sinus ; also anterior inferior cerebral veins and sinus alae parvae. The ophthalmic veins are two in number : superior, the larger, accompanies artery ; and inferior, running below optic nerve, is formed by lower ciliary and muscular branches, and communicates with pterygoid plexus ; both pass through the sphenoidal fissure to empty into the cavernous sinus.

Circular : surrounds pituitary body, connects the cavernous sinuses.

Inferior petrosal (2) : from termination of cavernous to in- ternal jugular vein, lies over petro-occipital suture.

Transverse : connects the inferior petrosal sinuses across basilar process of occipital bone.

Superior petrosal (2) : placed on superior border of petrous part of temporal, connecting lateral and cavernous sinuses ; receives inferior lateral cerebral, and anterior lateral cere- bellar veins.

Sinus alee parva (spheno-parietal) receives some meningeal \nd inferior cerebral veins, and runs inwards along free nargin of lesser wing of sphenoid to cavernous sinus.

Veins of the diploe : lodged in channels of the bones of the cranial vault. They are divided into frontal, joining the supra-orbital vein ; anterior temporal, joining a deep temporal vein ; posterior temporal, joining lateral sinus ; and occipital. joining occipital vein or lateral sinus.

VEINS

99

Emissary veins : small veins passing through foramina in the bones, and connecting the sinuses with the external veins of the head.

Facial: passes obliquely across side of face from inner canthus to anterior border of masseter, being the continua- tion of the angular vein from inner canthus of eye. Under the inferior maxilla near the angle it unites with a branch (communicating facial) from temporo-maxillary vein to form a short trunk (the common facial), which, crossing sub- maxillary gland, digastric and external carotid artery, empties into the internal jugular vein. Also communicates with oph- thalmic (vide cavernous sinus).

f supra-orbital.

anSular Ipalpe^ral (superior).

Inasal.

inferior palpebral. dorsal and lateral nasal.

alveolar branches.

The facial vein receives .. ..

anterior internal maxillary (deep- facial)

infra-orbital, descending palatine . naso-palatine. Vidian.

superior, ^inferior, buccal. masseteric. labial, submental. inferior palatine.

glandular (parotid and submaxillary). part of tamporo-maxillary.

Temporal : from side and vertex of head, passes down over zygoma, there receiving the middle temporal vein ; it then courses down between condyle of jaw and external auditory meatus into the substance of the parotid, where it joins the internal maxillary vein to form the temporo-maxillary trunk.

"anterior temporal, posterior temporal.

The temporal vein receives 4

middle temporal. parotid, anterior auricular, .transverse facial. ,

7— a

ioo THE POCKET ANATOMY

Internal maxillary : is formed by branches corresponding with those of the internal maxillary artery. The branches form a plexus (pterygoid) placed between the pterygoid muscles. The trunk of the vein passes backwards with artery internal to neck of condyle to join temporal vein, and form temporo-maxillary trunk.

/•middle meningeal (2). deep temporal, pterygoid. masseteric.

The pterygoid plexus is formed by

infra-orbital.

buccal.

superior palatine.

inferior dental.

posterior dental.

Vidian.

The pterygoid plexus communicates with the facial vein by the anterior internal maxillary vein (deep facial).

Temporo-maxillary : formed by union of temporal and internal maxillary veins ; descends in parotid gland on ex- ternal carotid artery and crossed by facial nerve, divides into two branches, one of which unites with the facial as the communicating facial, and the other receives the posterior auricular vein to form the trunk of the external jugular vein .

Posterior auricular : from plexus on side of head and back of ear, receives stylo-mastoid vein, and branches from ex- ternal ear; joins into temporo-maxillary to form external jugular vein.

Occipital : from plexus at back part of vertex of skull, placed deeply between muscles of neck, and having on scalp same course as artery; it then passes deeply under complexus, over suboccipital triangle, where it communicates with vertebral, and passes on semispinalis into deep cervical vein ; communicates with lateral sinus by mastoid veins.

External jugular : formed by junction of part of temporo- maxillary trunk and posterior auricular veins at angle of jaw in the substance of parotid. Descends beneath platysma over sterno-mastoid, pierces deep fascia near the clavicle to open into subclavian, or occasionally into the internal jugular. Has two pair of valves. Receives posterior external jugular, draining superficial region at back of neck, supra-scapular, transverse cervical, and frequently the anterior jugular .

Anterior jugular : drains integument and superficial muscles of anterior, ^ntf middje re^ionso of neck. Empties into sub- clavian or dfctfcrn^l jugular- : cpmfnunicates with *ellow just

VEINS 101

above the sternum, also with facial and external jugular veins.

Internal jugular: from jugular foramen, being formed by junction of lateral and inferior petrosal sinuses. Passes vertically down the side of neck, on the outer side of carotid artery, within the sheath, uniting with subclavian near the inner margin of the scalenus anticus to form the vena inno- minata.' Usually crossed by spinal accessory and communi- cans hypoglossi nerves. One pair of valves placed f inch above termination.

'pharyngeal.

f dorsal of tongue, lingual-! lingual venae comites.

[ranine. common facial.

The internal jugular vein receives . .

superior thyroid* middle thyroid.

Vertebral : communicates with posterior spinal and occipital veins; drains occipital region and deep muscles of back ot neck; enters foramen in transverse process of atlas, runs down behind artery through same foramina of the cervical vertebrae to 6th (or yth), where it passes down to enter vena innominata. One pair valves guard its mouth.

(muscular, anterior vertebral, deep cervical, ist intercostal.

Deep cervical (posterior vertebral) corresponds to profunda cervicis artery ; lies deeply in neck ; above receives occipital and ends in vertebral.

VEINS OF THE UPPER EXTREMITY.

A. SUPERFICIAL, LYING ON DEEP FASCIA.

Anterior ulnar : from the anterior and ulnar side of hand up along ulnar side of forearm to elbow-joint, to join the median basilic.

Posterior ulnar : from posterior ulnar border of hand and vein of little finger (vena salvatella), up along ulnar side of back of forearm to join median basilic just below the elbow-joint.

102 THE POCKET ANATOMY

Radial : from dorsum of the thumb, radial side of index- finger and hand, along outer side of forearm to join median cephalic near bend of elbow, and form the cephalic vein.

Median : from palmar surface of hand up the middle of forearm communicating below the bend of elbow, with venae comites of ulnar, and then divides into median cephalic and median basilic.

Median basilic : passes obliquely inwards over bicipital fascia, which separates it from the brachial artery. Empties into basilic.

Median cephalic : passes obliquely outwards from bend of elbow, between supinator longus and biceps. Empties into cephalic.

Basilic : formed by coalescence of anterior and posterior ulnar with the median basilic veins. Ascends on the inner side to middle of the arm, where it pierces deep fascia and joins brachial venae comites to form axillary vein.

Cephalic : passes up between deltoid and pectoralis major, perforates deep fascia and costo-coracoid membrane, and opens into the axillary vein. It is occasionally connected with the external jugular by a branch over the clavicle (jugulo-cephalic).

B. DEEP VEINS ACCOMPANYING THEIR RESPECTIVE ARTERIES AS VEN-ffi COMITES, INTERCOMMUNICATING WITH EACH OTHER, AND THE SUPERFICIAL VEINS FREQUENTLY.

Digital (2) : empty into the superficial palmar.

Palmar superficial (2) : empty into ulnar and radial.

Deep palmar : empty into radial venae comites.

Interosseous (2) : accompany the anterior and posterior interosseous arteries, commencing at the wrist, terminating in venae comites of the ulnar.

Comites radialis (2) : form, with the ulnar, the comites of brachial.

Comites ulnaris (2) : with the radial, form comites of brachial.

Comites brachialis (2) : receiving veins corresponding to the branches of the brachial artery, empty into the axillary vein.

Axillary (single) : formed by junction of brachial veins with the basilic. Commences at lower border of the axillary space ; receives veins corresponding to branches of its artery, and terminates in the subclavian at outer border ist rib. [Valves at inferior border of subscapularis, terminations of subscapular and cephalic veins.]

Subclavian : continuation of axillary, joins internal jugular vein behind the inner end of the clavicle to form vena

VEINS 103

innominata. Separated from its artery by scalenus anticus muscle and phrenic nerve. Receives external and anterior jugular veins. [Valves just external to entrance of external jugular, or about i inch from its termination.]

VEINS OF THE BODY.

Innominate : two large trunks, placed one on each side of the neck, and formed by the junction of the internal jugular and subclavian veins of the corresponding side. They end by uniting to form the superior vena cava. No valves.

The right innominate vein is short (i inch long), and, com- mencing behind the inner end of the clavicle, passes down- wards to join left innominate at the inferior border of ist right costal cartilage. Receives the right vertebral, right internal mammary, right inferior thyroid, and right superior intercostal veins. The right lymphatic duct opens at the angle of union of right subclavian and internal jugular veins.

Relations : —

In Front. Behind.

Right sterno-hyoid. Right pleura and lung.

Right sterno-thyroid. Clavicle.

ist costal cartilage. Thymus.

Left Side. Right Side.

Innominate artery and right Right lung and pleura,

pneumogastric nerve. Right phrenic nerve.

The left innominate is 3 inches long, passes from left to right and downwards. The thoracic duct opens at the angle of union of the left subclavian and internal jugular veins.

'left vertebral, left internal mammary, left inferior thyroid.

The left innominate vein receives-; left superior intercostal.

thymic. mediastinal. pericardiac. Relations : —

In Front. Below.

First piece of sternum. Arch of aorta (transverse part).

Origin of left sterno-hyoid. „ , . ,

Origin of left sterno-thyroid. ****

Thymus gland. Innominate artery.

Left ca» otid artery. Left subclavian artery. Left phrenic nerve. Left pneumogastric nerve.

104 THE POCKET ANATOMY

Internal mammary : two with each artery, uniting in a single trunk, emptying into innominate veins.

Inferior thyroid (sometimes 3 or 4) : from thyroid venous plexus, emptying into right and left innominate veins.

Superior intercostal : receives veins from 2nd and 3rd intercostal spaces. The right one passes down and enters the azygos major, the left passes forward across arch of aorta to left innominate vein, and receives the left bronchial vein.

Vena cava superior : 3 inches long, formed by the junction of the right and left innominate veins behind the junction of the ist right costal cartilage with the sternum ; passes down to the right auricle opposite upper border of 3rd right costal cartilage. The vena cava enters the pericardium about i£ inches from its termination, and this part is covered with serous membrane except posteriorly. No valves. Receives pericardial and mediastinal veins, and just as it enters the pericardium the azygos major vein.

Relations : —

Left Side. In Front. Right Side.

Innominate artery, in Pleura. Pleura.

upper part. Thymus gland. Right phrenic nerve.

Ascending part of aortic Costal cartilages and arch, in lower part. intercostal spaces.

Pericardium.

Behind. Pleura.

Right bronchus. Right pulmonary artery. Upper right pulmonary vein. Pericardium.

Azygos major: commencing opposite ist or 2nd lumbar vertebra by a branch from right lumbar veins, passes up through aortic opening in diaphragm to right of aorta, and along right side of column in front of right intercostal arteries to 3rd dorsal vertebra, where, arching over root of right lung, it empties into superior vena cava. Receives the ten lower right intercostal veins, venae azygoi minores (superior and inferior), several cesophageal, mediastinal, and right bronchial veins. Imperfect valves, though its branches have complete ones.

Azygos minor inferior : commencing in lumbar region of left side from lumbar veins, or branches of renal, passes through left crus of diaphragm to 8th dorsal vertebra, there crossing behind aorta and thoracic duct to terminate in azygos major.

VEINS 105

Receives three or four lower left intercostals ; some ceso- phageal and mediastinal veins.

Azygos minor superior: formed by union of 4th, 5th, 6th, 7th, and 8th left intercostal veins ; communicates above with superior intercostal vein, crosses yth dorsal vertebra behind aorta and thoracic duct to end in vena azygos major.

Bronchial : from lungs ; the right terminating in azygos major ; the left in the left superior intercostal.

SPINAL : Dorsi-spinales ; external to spinal canal, extend along whole length of back of spine, forming network, ter- minating in the vertebral (of neck), the intercostal (of thorax), lumbar and sacral veins.

Meningo-rachidian : situated between vertebra and dura mater, consisting of longitudinales spinales anteriores : whole length of anterior surface of vertebral canal, terminating in dorsi -spinal.

Longitudinales spinales posteriores : whole length of posterior surface of vertebral canal, terminating in dorsi-spinal.

Veins of the vertebrae : Vena basis vertebrarum : from bodies of vertebras, terminating in anterior longitudinal.

Veins of the spinal cord : Medulli-spinales : cover cord, between pia and arachnoid, from sacrum to occiput; anas. freely with contiguous veins. No valves in any of the spinal veins.

Iliaca externa, interna, and communis : see Lower Ex- tremity.

Vena cava inferior : formed by junction of the two common iliac veins in front and a little to the right of 5th lumbar vertebra, passes up on right side of aorta to posterior border of liver, where it becomes imbedded in a groove and receives the hepatic veins ; thence it goes through special opening in diaphragm between middle and right leaflets, enters pericar- dium, and opens into lower and back part of right auricle, its orifice being protected by the Eustachian valve.

Relations : —

In Front. Behind. Left Side.

Mesentery. Vertebral column. Descending aorta

Transverse part of duo- Right crus of dia- Right crus.

denum. phragm and psoas.

Pancreas. Right renal ^

Foramen of Winslow. Right lumbar _ •

Portal vein. Right supra-renal Arteries.

Posterior surface of liver. Right inferior phrenic,/ Hepatic ^

Right spermatic .

Riiht colic r arteries.

Right common iliac } Diaphragm.

io6 THE POCKET ANATOMY

flumbar branches, right spermatic, (ovarian in female).

The inferior vena cava riSht renal- receives

right supra- renal, inferior phrenic, hepatic.

CARDIAC VEINS : Vena cordis magna : from apex, up an- terior interventricular groove to base of ventricles, curving to left side and back part of heart, empties into coronary sinus ; guarded by two valves ; receives posterior cardiac and left cardiac veins.

Venae cordis mediae (posterior cardiac) : from apex up pos- terior interventricular groove, terminating in coronary sinus, guarded by valves.

Venae parvae (anterior veins) : three or four small branches from anterior surface of right ventricle, emptying into lower part of right auricle.

Venae Thebesii : drain muscular substance, opening into right auricle.

Bight or small coronary : from back of right auricle and ventricle, runs in auriculo-ventricular groove to open in right end of coronary sinus.

The coronary sinus : is the part of the great cardiac vein which is placed in the left auriculo-ventricular groove. Is i inch in length, and opens in the right auricle, the opening being guarded by the Thebesian valve. Receives branches as above, and a small straight vein at the back of the left auricle, the oblique vein of Marshall, the remnant of the left superior vena cava of the foetus.

Pulmonary : four in number ; commence in capillary net- work upon the pulmonary alveoli, uniting to form a trunk for each lobe ; the one of the middle lobe of the right lung unites with the one from the superior lobe, hence there are two veins from each side. No valves. Carry arterial blood and empty in to the left auricle, the left veins crossing the descend- ing thoracic aorta.

Relations at the root of the lung : —

From A dove Down. From Before Back. reside. Left Sid*.

Vein. Bronchus. Artery.

Artery. Artery. Bronchus.

Bronchus. Vein. Vein.

VEINS 107

THE PORTAL SYSTEM.

The veins of the portal system collect the blood from the digestive tract. They form a trunk, the vena portse, which enters the liver and breaks up into small branches in its sub- stance. The following veins form the portal system : —

Inferior mesenteric : drains rectum, pelvic, iliac, and descending colon. It lies to the left of its artery, and passing behind transverse part of the duodenum and the pancreas, and over left kidney, opens into the splenic vein. (The haemorrhoidal branches anastomose with the haemorrhoidal branches of the internal iliac.)

Superior mesenteric : drains small intestines, caecum, ascending and descending colon. It passes upwards in front and to right of superior mesenteric artery, in front of trans- verse part of duodenum, and behind neck of pancreas joins the splenic vein at the upper border of the pancreas to form the portal vein.

Splenic : commences in five or six tributaries in hilum of spleen ; these unite to form a trunk which passes below splenic artery from left to right, behind upper border of pan- creas, and in front of aorta ; joins superior mesenteric at a right angle.

The gastric or coronary : a large vein accompanying coron- ary artery from right to left along lesser curvature of stomach to cardia, where it receives cesophageal tributaries, and, passing to right behind lesser sac, opens into the vena portae.

The vena portsa : is formed by the union of the splenic and superior mesenteric veins in front of the right crus of dia- phragm and inferior vena cava, and behind the neck of the pancreas. Passes up behind first part of duodenum and then between the layers of the small omentum, behind and between the common bile-duct and hepatic artery, the duct being placed on the right and artery on the left, to transverse fissure of liver ; here it divides into right and left branches to corresponding lobes, and also gives an offset to the Spigelian lobe. Con- nected with the branch to the left lobe are in front the obliterated umbilical vein and behind the ductus venosus, the remains of a f jetal connection with the inferior vena cava.

io8

THE POCKET ANATOMY

The portal vein re-< ceives ..

splenic

superior mesen- teric ..

gastric or coronary, pyloric. Lcystic.

splenic bran- ches.

vasa brevia of stomach.

pancreatic.

left gastro-epi- ploi'c.

inferior senteric

Heft colic.

me- 1 siSmo.id- -| superior

* * I haemor- rhoidal.

intestinal, ileo-colic. right colic, middle colic, right gastro-

epiploi'c. pancreatic, pancreatico-

duodenal.

VEINS OF THE LOWER EXTREMITY.

SUPERFICIAL SET.

Internal or long saphenous : from plexus on dorsum and inner side of foot ; ascends, in front of inner ankle, behind inner margin of tibia, accompanied by internal saphenous nerve ; bends behind inner condyle of femur, ascends along inner side of thigh, through saphenous opening, empties into femoral i£ inches below Poupart's ligament, where it receives superficial circumflex iliac, superficial epigastric, and superficial external pudic. Communicates with internal plantar, tibial, etc. Two to six valves.

External or short saphenous : from plexus on dorsum and outer side of foot, up behind outer ankle to median line of leg, accompanied by external saphenous nerve ; empties into popliteal vein, between the heads of the gastrocnemius. Two valves, one near termination. Communicates with deep veins of foot.

VEINS

109

DEEP SET.

Posterior tibial : two venae comites, formed from external and internal plantar, joining with the peroneal. Course same as artery.

Anterior tibial : two venae comites, continuation of vena dorsales pedis, pierce interosseous membrane at upper part of leg, and form the popliteal vein, by junction with the pos- terior tibial veins, at the lower border of the popliteus muscle.

Popliteal (see anterior tibial) : passes up to femoral aper- ture in adductor magnus, there becoming the femoral ; re- ceives sural, articular, and external saphenous veins. Four valves. Placed superficial to artery, which it crosses as it ascends, from within outwards.

Femoral (see above) : passes from the opening in the adductor magnus up to Poupart's ligament, there becoming external iliac. Lies at first to outer side of artery, but higher up crosses behind to its inner side. Receives muscular branches, profunda femoris, and the internal saphenous. Four or five valves.

External iliac (see above) : from Poupart's ligament to sacro-iliac synchondrosis, there uniting with the internal iliac to form common iliac. On right side, lies to inside of artery at first, but gradually passes behind it. On left side, alto- gether on inside of artery. Receives deep epigastric and deep circumflex iliac, and a. pubic vein from the obturator.

Internal iliac : formed by the union of all of the venae comites of the branches of the internal iliac artery, except the ilio-lumbar veins which open into the common iliac. It lies at first on the inner side, but finally gets behind the artery. It has no valves. The visceral veins opening into the internal iliac anastomose very freely and form a series of plexuses.

C superior and haemorrhoidal I middle plexus . . j haemor- \ rhoidal.

The internal iliac vein receives

visceral branches

fvesical.

vesico-prosta- 1 dorsal of penis, tic plexus . . 1 deep veins of

\. penis, uterine

no

THE POCKET AN 'ATOM Y

The internal iliac vein receives

parietal branches

obturator.

internal pudic

sciatic .. ..

gluteal. .lateral sacral.

veins of corpus

cavernosum. veins of bulb, transverse peri-

neal. superficial peri«

neal. inferior

hsemorrhoidal. fcoccygeal. I comes nervi | ischiadici. \ muscular.

Common iliac (see external iliac) : from base of sacrum to terminate on 5th lumbar vertebra, a little to the right of the middle line, where, with its fellow of opposite side, it forms vena cava inferior. The right vein is the shorter, and nearly vertical. Receives ilio-lumbar and sometimes lateral sacral veins. Middle sacral empties into left common iliac. No valves.

Relations. — Right vein passes behind, and then to right side of artery. Left vein is placed on inner side of left artery, and then passes behind right common iliac artery to join right vein, crossing middle sacral artery.

THE ABSORBENT SYSTEM.

The thoracic duct receives the absorbents from both lower limbs, abdomen, except upper surface of liver, from left half of thorax, left upper limb, and left side of head and neck.

Length. — 15 to 18 inches.

Extent. — From 2nd lumbar vertebra, where it commences by a dilatation, the receptaculum chyli, to junction of left internal jugular with left subclavian vein. - Relations. — The abdominal part is placed on the front of the body of the 2nd lumbar vertebra, behind and to the right side of the aorta and on the inner side of the right crus ; it then enters the thorax through aortic opening, on the right side of aorta, lying between it and the vena azygos major, and passes upwards to right of aorta on right intercostal

THE ABSORBENT SYSTEM in

vessels. Opposite the 4th dorsal vertebra it passes to the left behind aortic arch, and runs along the left side of the oeso- phagus, behind the left common carotid artery. At the level of the yth cervical vertebra it turns outwards, and passing behind left internal jugular and crossing ist part of left sub- clavian artery, archies over the apex of the left pleura to open at the angle of union of the left internal jugular and left subclavian veins.

The right lymphatic duct : receives the absorbents of the right limb, right side of chest, right half of head and neck, and upper surface of liver. It is about ^ inch long, and enters the venous system at the angle of union of the right internal jugular and right subclavian veins.

THE LYMPHATICS OF THE HEAD AND NECK.

Suboccipital glands (i or 2) : receive lymphatics from back of scalp, efferent vessels join superficial cervical glands.

Mastoid glands (2 or 3) : receive lymphatics from back of ear and external auditory meatus, efferent vessels join super- ficial cervical glands.

Parotid lymphatic glands (3 or 4) : one being placed just anterior to tragus. Receive lymphatics from temporal region, external auditory meatus and eyelids ; efferent vessels pass to submaxillary and superficial cervical glands.

Internal maxillary glands: afferent vessels from temporal, nasal, zygomatic, and orbital fossae, palate and upper part of pharynx; efferent vessels pass to superior deep cervical glands.

Submaxillary lymphatic glands (8 to 10) : afferent vessels from face, floor of mouth, submaxillary and lingual glands ; efferent vessels to cervical glands.

Superficial cervical glands (4 to 6) : placed along the ex- ternal jugular vein. Afferent vessels from external ear, skin of neck ; efferent vessels to the deep cervical glands.

Deep cervical glands (20 to 30) : glandulas concatenate.

Superior: lie along internal jugular vein from division of common carotid to base of skull. Afferent vessels from in- ternal maxillary and submaxillary glands, cranium, tongue, larynx, lower part of pharynx and thyroid body. Efferent vessels to inferior set.

Inferior: placed along lower part of internal jugular vein. Afferent vessels from other cervical glands and lower part of neck. Efferent vessels form a single trunk {Jugular lymphatic trunk), opening into thoracic duct on left side, and into the right lymphatic duct on right side.

THE POCKET ANATOMY

THE LYMPHATICS OF THE UPPER LIMB.

The lymphatics of the arm are arranged in a superficial and a deep set which enter the axillary glands, except a few superficial which join the gland over the internal condyle.

There are two sets of lymphatic glands in the arm, viz., superficial and deep.

The superficial lymphatic glands : one or two above the internal condyle (epitrochlear).

The deep lymphatic glands : two or three on inner side of brachial artery.

The axillary glands (10 or 12) : receive the lymphatics from the upper limb.

Axillary set: placed along axillary vessels, afferent vessels from limb.

Pectoral set: placed along long thoracic artery, afferent vessels from mamma and chest.

Subscapular set: placed along subscapular artery, afferent vessels from the back.

Infra-clavicular set: situated below the clavicle, in the hollow between pectoralis major and deltoid ; afferent vessels from shoulder and efferent vessels from pectoral set.

THE LYMPHATICS OF THE PELVIS AND ABDOMEN.

External iliac glands (6 to 10) : lie along external iliac artery ; afferent vessels from inguinal glands.

Internal iliac glands: placed along internal iliac artery; afferent vessels from pelvic viscera.

Sacral glands : placed in hollow of sacrum, receive lymphatics of rectum.

Lymphatics of bladder : placed near base of bladder ; efferent vessels enter internal iliac glands.

Lymphatics of uterus : in the impregnated state enter in- ternal iliac glands.

Lumbar lymphatic glands : mesial group, surround aorta and vena cava ; afferent vessels from external and internal iliac, and sacral glands, lymphatics of kidney, supra-renal bodies, testicles (ovaries), etc. The lateral group lie behind psoas, and receive the deep lymphatics of the abdominal wall. The efferent vessels of the whole enter the thoracic duct.

Mesenteric glands (130 to 150) : disposed around the trunk and branches of the superior mesenteric artery; efferent vessels go to the thoracic duct.

Cceliac glands (16 to 20) : surround cceliac axis. The afferent

THE ABSORBENT SYSTEM 113

vessels come from stomach, spleen, pancreas, and liver ; the efferent vessels go to the thoracic duct.

THE LYMPHATICS OF THE THORAX.

Sternal glands (6 to 10) : along internal mammary artery. The afferent vessels come from front of chest and abdominal walls, diaphragm and under part of mamma ; the efferent vessels join anterior mediastinal glands and thoracic duct.

Intercostal glands: placed posteriorly on heads of ribs. The afferent vessels come from chest wall ; the efferent open into the thoracic and right lymphatic ducts.

Anterior mediastinal glands (3 or 4) : between pericardium and sternum. The afferent vessels come from lower sternal glands, upper surface of liver and diaphragm : the efferent vessels pass to thoracic and right lymphatic ducts.

Superior mediastinal or cardiac glands (8 to 10) : placed in front of the arch of the aorta in the superior mediastinum. The afferent vessels come from the heart, pericardium and thymus gland ; the efferent vessels unite in two or threp trunks which open into the thoracic and right lymphatic ducts.

Bronchial glands : are placed behind and between the bronchi. The afferent vessels come from the lung ; the efferent vessels join to open into the thoracic and right lym- phatic ducts.

Posterior mediastinal glands (8 to 12) : lie along descending thoracic aorta. The afferent vessels come from the oesophagus, pericardium, and diaphragm ; the efferent vessels, go to the thoracic duct.

THE LYMPHATICS OF THE LOWER LIMB.

The lymphatics of the lower limb are divided into a super- ficial and a deep set. The superficial, except a few which pass to the popliteal glands, go to the superficial inguinal glands. The deep lymphatics enter the deep inguinal glands.

The popliteal glands (4 or 5) : are placed on the popliteal vessels. The afferent vessels come from the lymphatics of the leg ; the efferent go to the inguinal glands.

The superficial inguinal glands (8 to 10) :

Oblique set: lie along Ponpart's ligament. The afferent vessels come from trunk, buttocks, anal canal, perineum, and external genitals, including membranous and spongy urethra in the male and lower third of vagina in female.

Vertical or femoral set : lie along the internal saphenous vein, and receive the superficial lymphatics of the limb. The efferent vessels of both sets join the deep glands.

8

H4 THE POCKET ANATOMY

The deep inguinal glands : surround the femoral vessels (a constant one in the crural canal) . The afferent vessels come from the superficial inguinal glands and the deep lymphatics of the limb ; the efferent vessels join the external iliac glands.

THE SPINAL CORD.

The spinal cord is the part of the cerebro-spinal axis whick occupies the spinal canal. In the adult it occupies about § of the length, but in the foetus, before the third month, it extends the whole length of the canal.

Extent. — The spinal cord extends from the lower border of the foramen magnum, where it is continuous with the medulla oblongata above, to the lower border of the ist lumbar ver- tebra, there terminating in a slender filament, the filum terminal*.

Contents of the Neural Canal.

Venus plexus between bone and dura mater.

( dura mater. Membranes < arachnoid.

( pia mater, with ligamenta denticulata. Cerebro-spinal fluid.

So'nal essels i anterior sPinal artery and vein.

\ two posterior spinal arteries and veins. Spinal cord, with anterior and posterior roots of nerves.

Shape.— In transverse section, nearly round, except at the enlargements, where it is more elliptical.

Enlargements. — Presents two enlargements. The upper or cervical extends from the upper limit of the cord downwards to the ist or 2nd dorsal vertebra.

The lower or lumbar commences opposite the loth dorsal vertebra; is largest at the 1 2th dorsal, and thence tapers, forming the conns medullaris, from the tip of which the filum terminate descends.

The filum terminale (central ligament of the cord) : passes from the end of the conus medullaris downwards in the middle of the cauda equina ; becomes closely invested with dura mater opposite the ist or 2nd sacral vertebra, and blends with the periosteum at the lower end of the sacral canal.

It is a process of pia mater, containing in its upper half the continuation of the central canal of the cord, together with a little grey matter for a short distance. The lower half con- sists of connective-tissue, bloodvessels and medullated nerve-

THE SPINAL CORD 115

fibres. The anterior spinal artery is continued along the front ; it is a very slender vessel.

The nerve-roots. — Consist of anterior and posterior bundles, 31 pairs (see p. 158).

The anterior roots are arranged irregularly along the side of the cord ; the posterior roots issue in a straight line along the postero-lateral groove. They are distinguished from the anterior roots by having a ganglion and by their larger size.

The nerve-roots pass outward to the intervertebral fora- mina, those in the upper part passing almost transversely ; below they pass more obliquely, until in the lower part of the canal their course is vertical. The collected bundles of nerve-roots at the termination of the cord form the cauda equina.

FISSURES.

Anterior median fissure : along the anterior surface of the cord in the middle line. Extends into the substance of the cord for about a third of its thickness, but deeper below than in the upper part. Does not reach grey matter. Lined with pia mater.

Posterior median fissure : not a true fissure, and only con- tains a septum of pia mater. Reaches down to grey matter.

Lateral fissures : Antero-lateral : not a true fissure, but a line corresponding to origin of anterior nerve-roots.

Postero-lateral : corresponding to attachment of posterior nerve roots.

Columns of the cord : —

The cord being divided into two lateral halves by the median fissures, may again be subdivided into anterior, lateral, and posterior columns.

The posterior and lateral columns are separated by a groove or lateral sulcus, to which the posterior nerve-roots are attached.

The anterior and lateral columns are separated by the an- terior roots of the nerves.

The posterior column is subdivided by a groove (only found in the upper part of the cord), a little outside the posterior median fissure, into two columns, the postero-mesial (of Goll) and the postero-lateral (of Burdach).

STRUCTURE OF THE SPINAL CORD.

The spinal cord in transverse section consists of white matter externally, and grey matter internally.

The grey matter : consists of a crescent-shaped portion it)

8—2

n6 THE POCKET ANATOMY

each lateral half of the cord, united by an intervening pro- cess, the posterior or grev commissure.

Each crescent has two cornua, an anterior, thick and short, not reaching the surface of the cord ; and a posterior, long and slender, reaching to the postero-lateral fissure, just before reaching which it becomes enlarged, caput cornu, and becomes less opaque (substantia gelatinosa of Rolando). The size of the grey crescents varies in different parts of the cord, being largest in the cervical and lumbar enlargements. In the upper dorsal region there is a projection of the grey matter on the outer side of the crescent between the anterior and posterior cornu, called the intermedia-lateral tract or lateral cornu.

Central canal : extends through the whole length of the cord in the middle of the posterior or grey commissure. It is lined with a spheroidal ciliated epithelium. Opens above into the floor of the 4th ventricle, and is continued below into the upper part of the filum terminale.

The white matter : encloses the grey matter in each lateral half of the cord, except where the posterior cornu comes to the surface. The portion of white matter between the pos- terior or grey commissure and the anterior median fissure constitutes the anterior or white commissure.

THE MEMBRANES OF THE SPINAL CORD.

The DURA MATER is the most external membrane, and is continuous with that investing the brain ; but it does not form the periosteum of the vertebrae, nor has it any sinuses, but is separated from the bones by areolar tissue and a plexus ot veins. It is connected above with the edge of the foramen magnum ; at the top of the sacrum it becomes im- pervious, and is continued as a slender cord to blend with the periosteum of the coccyx. This membrane gives sheaths to all the spinal nerves.

The PIA MATER is less vascular, thicker, and more fibrous than that investing the brain. It has an external fibrous layer of longitudinal bundles having a fold, the linea splendens, dipping into the anterior fissure, and a smaller one passing into the posterior fissure. The pia mater ends in a slender cord, the filum terminale, which is within the prolongation of the dura mater. A process of pia mater, the ligamentum denticulatum , passes outwards towards the dura, to which it is attached by twenty-two tooth-like processes situated between the origins of the spinal nerves ; its pial origin is continuous, and lies between the anterior and posterior nerve-roots.

The ARACHNOID is placed outside the pia mater, and loosely

THE BRAIN

117

invests the cord. The subarachnoid space of the cord is large, and is imperfectly divided by the ligamentum denticulatum, into an anterior and a posterior portion. The posterior por- tion is further subdivided by the septum posticum, which passes from the posterior fissure backwards to the opposite part of the arachnoid, and contains the larger bloodvessels. Trabe- culse also pass between the nerve-roots and the inner surface of the arachnoid, and between the posterior nerve-roots and the septum posticum.

THE BRAIN.

Sylvian aqueduct, crura cerebri. corpora quadri-

gemina. 3rd ventricle, optic thalami. pineal body, posterior perforated

spot.

corpora albicantia. tuber cinereum. pituitary body, optic commissure, lamina cinerea. convolutions, fissures.

corpus callosum. lateral ventricles. 5th ventricle, septum lucidum. for nix.

foramen of Munro. velum interpositum choroid plexuses, corpora striata. claustrum. tasnia semicircularis nucleus amygdalae, anterior commissure.

	'medulla ob- longata. cerebellum, pons Varolii. s
		mesence- phalon . .
		thalamen- cephalon
The brain . consists of '	cerebrum . . <
		cerebral hemi- spheres. •

n8 THE POCKET ANATOMY

THE MEDULLA OBLONGATA, OR BULB.

Extent. — From the lower border of the foramen magnum to the lower border of the pons Varolii.

Connections. — Inferiorly it is connected with the spinal cord, superiorly it is continued into the pons, anteriorly it rests upon the basilar groove, and posteriorly it lies in a depression between the hemispheres of the cerebellum, called the valle- cula, and here bounds the lower half of the floor of the 4th ventricle.

Dimensions. — 1£ inches long ; greatest breadth f inch.

Shape. — Pyramidal, with base at the pons, and apex at the spinal cord.

Fissures. — Anterior and posterior median fissures, con- tinuous with those of the cord.

Anterior median fissure: terminates just below the pons in the foramen cfscum. The fibres of the anterior pyramids decus- sate at the lower part of the fissure, and partly interrupt it.

Posterior median fissure : continues up from the cord to about half-way up the medulla, where it widens out into the fossa rhomboidalis or floor of the 4th ventricle.

Structure of the medulla. — If the parts of the spinal cord are traced into the medulla, its structure will be easily under- stood.

The line of the posterior roots of the spinal nerves is continued by the upper bundles of the nerve-roots of the spinal acces- sory nerve, above this by the bundles of the vagus, and above this, again, by the bundles of the glosso-pharyngeal nerve.

The line of exit of these nerve-roots represents the postero- lateral groove of the spinal cord. As this line is traced up- wards it turns ventrally outwards, so that about half-way up the medulla it appears upon the lateral surface, and in its upper part it lies close to the posterior margin of the olivary body, from which it is separated by a narrow groove.

The part behind these nerve-roots is termed the posterior area of the medulla, and corresponds to the posterior columns (postero-mesial and postero-lateral) of the cord.

The line of the anterior roots of the spinal nerves, when traced up into the medulla, deepens into a groove which is continued upwards nearly as far as the pons.

The bundles of the nerve-roots of the hypoglossal issue from this groove. The part of the medulla between this groove and the anterior median fissure is called the anterior area, and corresponds to the anterior column of the cord.

THE BRAIN 119

The part between the anterior and posterior areas — that is, the part between the line of issue of the nerve-roots of the spinal accessory, vagus, and glosso-pharyngeal nerves, and line of issue of the nerve-roots of the hypoglossal— is called the lateral area, and corresponds to the lateral column of the cord.

Posterior area of the medulla. — The postero-mesial column (of Goll) of the cord is continued up into the medulla as the funiculus gracilis, which expands as it approaches the 4th ventricle. This expansion is called the clava ; and upon reaching the 4th ventricle the clavae of opposite sides open out to form the lateral boundary of the ventricle in its lower part.

The postero-lateral column (of Burclach) of the cord is continued upwards into the medulla, where it expands slightly, and is called the funiculus cuneatus, which, on the same level with the clava, has an eminence, the cuneate tubercle.

Between the funiculus cuneatus and the line of origin of the nerve-roots of the spinal accessory, vagus, and glosso-pharyn- geal, there appears in the lower part of the medulla a longi- tudinal prominence, \he funiculus of Rolando, which broadens out above into the tubercle of Rolando. It is formed by the approach of the caput of the posterior cornu to the surface.

The Restiform body. — :In the upper part of the medulla, a set of fibres issue from the anterior median fissure, pass trans- versely outwards over the anterior pyramid and olivary body, and, continuing transversely, cross over the funiculus of Rolando and the cuneate funiculus, to turn upwards on these. They are the superficial arciform or arcuate fibres, and are mainly derived from the gracile and cuneate nuclei of the same and opposite sides; joined to these, just above the tubercle of Rolando, are some transverse fibres which come from the lateral column, known as the direct cerebellar tract. These oblique fibres blend with the funiculus of Rolando, and with the superficial fibres of the funiculus gracilis and funiculus cuneatus, the whole forming the restiform body. Superiorly the restiform body diverges from its fellow and enters the cerebellum, of which it forms the inferior peduncle.

Lateral area of the medulla. — The lateral column of the cord, as continued into the medulla, consists of three sets of fibres. One set, the crossed pyramidal tract, crosses obliquely through the anterior column and across the anterior median fissure to the opposite side, where they form the greater part of the pyramid. A second set coasts o{ the direct cerebellar

120 THE POCKET ANATOMY

tract which join the restiform body, whilst the rest of the column passes upwards as far as the lower end of the olive which conceals it.

The olivary body is an oval prominence lying in the upper part of the medulla, between the pyramid and the restiform body. It is separated from the pons by a groove, which con- tains some of the external arcuate fibres.

On the inner side lie the nerve-roots of the hypoglossal ; and on the outer side, but separated from it by a groove, the roots of the accessory, vagus, and glosso-pharyngeal nerves issue. Longitudinal fibres, prolonged from the lateral column, lie in the groove on the outer side of the olive, and occasionally a few bundles of longitudinal fibres are seen on the inner side. These, together with the arched fibres above and below, give it the appearance of being enclosed in a capsule.

The fillet of the olivary body is a small bundle of fibres derived from the capsule, and from the longitudinal fibres from the lateral tract. The fibres ascend in the crus cerebri.

Anterior area of the medulla. — Most of the fibres of the anterior columns of the cord are prolonged upwards deeply beneath the pyramids, but a bundle varying in size passes upwards on the outer side of the crossed portion of the lateral column (crossed pyramidal tract). These fibres form the direct Pyramidal tract.

The pyramids are two oval prominences, broader above than below. They are placed one on each side of the anterior median fissure. They consist of two sets of fibres, the outer derived from the anterior column of the cord, the inner from the lateral column of the opposite side. The crossing of the two sets of these latter fibres constitutes the decussation of the Pyramids.

The fourth ventricle. The central canal of the cord ex- pands in the upper and posterior part of the medulla until opposite the middle peduncles of the cerebellum, where it again gradually narrows, and becomes continuous with the Sylvian aqueduct above. The floor or anterior (ventral) wall of the ventricle is thus diamond-shaped. The lower end has been compared in shape to a pen, and is hence termed the calamus scriptorius.

The floor in the lower half is formed by the upper part of the posterior surface of the medulla, and in the upper half by the back of pons Varolii.

THE BRAIN 121

Structures on the floor. Lower half. Median groove.

Inferior fovea. — A triangular pit on each side of the median groove near the striae acusticae, the apex being directed upwards. From the base two grooves pass down- wards, one towards the calamus scriptorius, and the other towards the lateral boundary. Three areas are thus marked off in each lateral half of the medullary portion : —

1. Trigonum hypoglossi, next to median groove, subjacent

to which is the hypoglossal nucleus.

2. Trigonum vagi, included between the two grooves

passing from the fovea. Contains nucleus of vagus below, and nucleus of glosso-pharyngeal above.

3. Trigonum acustici (lower half), most external, con-

tains chief part of auditory nucleus, forming part of acoustic tubercle.

Upper half. Median groove.

Superior fovea. — A triangular depression in a line with the inferior fovea, dividing off each lateral half into three areas, viz. : —

1. Fasciculus teres, most internal, here raised into the

eminentia teres, and continuous with the trigonum hypoglossi below.

2. Locus cceruleus, a depression extending from the

superior fovea to the upper end of the ventricle, beneath which is some pigment, the substantia nigra.

3. Tuberculum acusticum (upper half).

Issuing from the median groove, and passing outwards on each side over the middle of the tuberculum acusticum are some white lines, the stria acusticee.

Lateral recess. — This is a lateral extension between the cere- bellum and the medulla of the cavity of the ventricle at its widest part.

The roof : in the lower half is formed by pia mater, lineti with epithelium. It has three apertures, one on each side in the lateral recess, and the third at the apex of the calamus scriptorius, the foramen of Majendie, by which the 4th ventricle communicates with the subarachnoid space.

On each side where the pia mater is attached laterally to

122 THE POCKET ANATOMY

the ventricle it is thickened by white matter, and is termed the ligula ; and at the apex of the calamus another thickening, the obex, occurs. Projecting from the roof on each side of the middle line is the choroid plexus.

In the upper half, the roof is formed by the converging superior peduncles of the cerebellum and the intermediate superior medullary velum or valve of Vieussens, continuous with the white matter of the cerebellum. Grey linear thickenings on the valve of Vieussens, continuous with the grey cerebellar cortex, constitute the lingula.

BOUNDARIES OF THE 4*TH VENTRICLE.

Laterally. Floor. Roof. | f Clavseoffuniculigraciles. Medulla (below . Pia mater (below).

"^ -? Funiculi cuneati. Nodule of inferior vermi-

^ ^ Restiform bodies. Pons (above). form process.

^ ,- Valve of Vieussens, and

§ I Superior peduncles of Superior peduncles of

"* \ cerebellum. cerebellum (above).

Grey Matter of the Medulla.

1. Remains of grey matter of cord.

(a) Grey tubercle of Rolando, from posterior cornu,

appears in front of restiform body.

(b) Remains of grey commissure, part continued into

vagus and auditory nuclei , and part into fasciculus teres.

(c) Remains of anterior cornu, intersected by white

fibres, giving rise to the formatio reticularis of medulla.

2. bpecial deposits of grey matter.

(a) Nucleus of hypoglossal.

(b) Nucleus for accessory part of spinal accessory.

(c) Nucleus of vagus, passing above, under auditory

nucleus, into nucleus of glosso-pharyngeal.

(d) Nucleus of glosso-pharyngeal.

(e) Nucleus of auditory nerve.

(/) Corpus dentatum, or nucleus of the olivary body. (g) Accessory olivary nucleus.

THE PONS VAROLII.

Position. Placed above the medulla, below the cruracerebri,

and between the lateral halves of the cerebellum.

THE BRAIN 123

Dimensions. — About i£ inches long, and about 2 inches transversely.

Anterior surface is convex, grooved along the midline for the basilar artery ; has transverse markings, and openings for the entrance of vessels.

Posterior surface : smaller than the anterior, and continuous with the posterior surface of the medulla ; part of it forms the upper part of the floor of the 4th ventricle.

Laterally : transverse fibres pass outwards and backwards from it, forming the middle cerebellar peduncles.

Upper border : longer than the inferior, with a notch in the median line corresponding to the groove on the anterior surface.

Lower border : slightly arched, overlapping the upper part of the medulla.

Structure: Alternating layers of transverse and longitu- dinal fibres, with intermingled grey matter. The transverse fibres come from the middle peduncles of the cerebellum, and pass to the crura cerebri ; the longitudinal are the continua- tion upwards of the fibres of the medulla.

Most anteriorly is a layer of transverse fibres of the middle peduncles ; behind these, longitudinal fibres prolonged from the anterior pyramids of the medulla with intermingled trans- verse peduncular fibres. More posteriorly is a deep layer of transverse fibres, most marked at the lower part of the pons, where they form the corpus trapezoides, and behind these are longitudinal fibres prolonged from the formatio reticularis of the medulla, the lateral tract and the olivary fillet. A septum of commissural fibres exists at the posterior part of the pons.

The grey matter of the pons. — In addition to the grey matter scattered in the above-mentioned formatio reticularis are the following special deposits : —

(a) Superior olivary nucleus. Placed posteriorly near the outer side of the corpus trapezoides.

(b) Nucleus of the facial nerve. Lies in formatio reticu- laris, just behind superior olivary nucleus.

(c) Motor nucleus of the 5th nerve.

(d) Upper sensory nucleus of the 5th nerve, placed outside motor nucleus.

(e) Continuation upwards of principal auditory nucleus. (/) Superior auditory nucleus, placed just outside principal

nucleus.

Accessory auditory nucleus.

k) Nucleus of the 6th nerve, corresponding to the part of fasciculus teres, above the auditory s*riae (vide 4th ventricle).

(g) (h]

124 THE POCKET ANATOMY

THE CEREBELLUM.

The cerebellum is contained in the occipital fossae, being separated from the cerebrum above by the tentorium. It consists of two lateral hemispheres connected together by the vermiform process, which projects considerably upon the under surface, forming the inferior vermiform process; but on the upper surface only forms a slight ridge, the superior vermiform process, continuous with the hemispheres laterally.

The inferior surface of each hemisphere is convex, and between them there is a fossa, the vallecula, at the bottom of which the inferior vermiform process lies, and -which is con- tinuous posteriorly with a notch between the two hemi- spheres. The medulla is in contact with the anterior part of the vallecula, and the posterior part receives the falx cerebelli.

Laminae and fissures. The surface of the cerebellum consists of lamina, which are separated by sulci or fis- sures.

The great horizontal fissure divides each hemisphere into an upper and a lower part. It commences at the pons in front, and passes horizontally round the circumference to end at the notch behind.

Lobes. On the upper surface of the cerebellum are the following lobes : —

(a) Central : a small lobe, forming the anterior part of the superior vermiform process. It is continued forwards on to the valve of Vieussens, forming the lingula (vide roof of 4th ventricle, p. 122), and laterally on to each hemisphere by a winglike fold, the ala.

(b) Lobus culminis : the culmen monticuli forms the highest part of the superior vermis, and on each side is continuous with the anterior crescentic lobe of the lateral hemisphere ; posteriorly the sulcus preclivalis separates it from —

(c) Lobus clivi : consists of the mesial clivus monticuli, connect- ing on either side the two posterior crescentic lobes, which are broad.

(d) Lobus cacuminis : behind the sulcus postclivalis, con- sists of a single folium of the superior vermis, folium cacu- minis, connecting the large postero-superior lobes of the lateral hemisphere.

THE BRAIN 125

On the under surface of the cerebellum are the following lobes from before backwards :

(a) Lobus noduli, comprising the nodule of the inferior vermis and the flocculus of each side, with a delicate connecting white lamina, inferior medullary velum.

(b) Lobus uvula. — The uvula forms a considerable part of inferior vermis , it is connected by a low ridge, the furrowed band crossing the sulcus valleculae, with the prominent tonsil or amygdala.

(c) Lobus pyramidis : the prominent mesial pyramid con- tinuous laterally with the biventral lobes.

(d) Lobus tuberis : comprises the tuber valvula, which is the posterior part of the inferior vermis and the postero- inferior lobes of the lateral hemisphere; the latter is sub- divided into lobus gracilis in front and inferior semilunar lobe behind.

STRUCTURE.

White matter : in each hemisphere there is a central white mass, containing in its middle a grey nucleus, the corpus dentatum.

The white centre sends processes into the laminae, and is prolonged anteriorly into the crus cerebelli, which divides into three peduncles, viz. : —

Superior peduncle : passes to the base of the corpora quad- rigemina and cerebrum.

Connecting the bases of the two superior peduncles is the valve of Vieussens.

Middle peduncle (the cerebellar commissure) : forms the transverse fibres of the pons.

Inferior peduncle : connects the cerebellum with the medulla and cord ; it passes downwards at the back of the medulla, forming the restiform body.

The white matter in the vermiform processes consists of a central part, projecting into the laminae of the pro- cesses.

Anteriorly it is continued into the inferior medullary velum.

Grey matter of the hemispheres :

A cortical layer : forming a continuous covering of the cere- bellum.

126 THE POCKET ANATOMY

The corpus dentatum, or ganglion of the cerebellum, is a dentated capsule of grey matter enclosing white substance, situated in the middle of the white matter of the hemisphere. It is open at its anterior part, whence white fibres issue, passing to the superior peduncles and valve of Vieussens.

Nucleus emboliformis : covering hilum of corpus den- tatum.

Nucleus globosus : placed on the inner side of the preceding, but at a lower level.

Nucleus fastigii : in the anterior part of the white centre of the vermiform process.

The arrangement of white and grey matter in the cere- bellum gives on section an arborescent appearance, the arbor vita.

THE MESENCEPHALON.

The Sylvian aqueduct (iter a tertio ad quartum ventriculum) is about ^ inch long. Posteriorly it is continuous with the narrowed upper end of the 4th ventricle, and anteriorly it opens out into the 3rd ventricle. It has a ciliated epithelial lining, and outside this a layer of grey matter, both being continuous with corresponding parts of the 4th ventricle. Laterally and below are the crura cerebri, whilst posteriorly is the lamina quadrigemina bearing the corpora quadri- gemina.

The grey matter of the aqueduct contains the nuclei of the 3rd and 4th nerves, and the upper nucleus of the 5th nerve.

The crura cerebri extend from the upper border of the pons, and, diverging, pass under the optic tract into the cerebral hemispheres. Between the crura is the interpedun- cular space, containing the posterior perforated spot, the cor- pora albicantia, pituitary body, infundibulum, and the tuber cinereum. Near the angle of divergence the roots of the 3rd nerve issue from a groove on the inner side, which groove indicates the separation of the ventral part (crusta or pes pedunculi) from the dorsal portion (tegmentum) of the crus.

There is a layer of grey matter placed between the pes pedunculi and the tegmentum, known as the substantia nigra or locus niger.

The pes, or crusta pedunculi, consists of longitudinal white fibres, of which the middle third are continuous with the anterior pyramid of the medulla, and pass to the internal capsule.

THE BRAIN 127

The tegmentum consists of white longitudinal fibres and interspersed grey matter, continuous with the formatio reticu- laris of the medulla and pons, and passing above into the optic thalamus. Two more or less definite white longitudinal tracts are here passing upwards, the fillet and the superior cerebellar peduncle, which latter decussates with its fellow beneath the aqueduct.

The corpora quadrigemina are four small bodies placed in pairs, superior and inferior corpora quadrigemina.

Relations : —

In front. Above. Below,

3rd ventricle. Posterior border of Aqueduct of

Posterior commissure. corpus callosum. Sylvius.

The corpora quadrigemina of opposite sides are separated by a longitudinal groove, which is connected below with the superior medullary velum ; the superior corpora quadri- gemina are partly concealed by the overlying pineal gland. From the outer side of each corpus there proceeds a white tract, the brachium. The brachia from the inferior corpora go to the inner geniculate body, and the brachia from the superior bodies pass into the optic tract between the inner geniculate body on the one hand, and the optic thalamus and the external geniculate body on the other hand.

Structure. — The inferior bodies consist of a grey nucleus enclosed in a thin capsule of white fibres. The white fibres, separating the nuclei and the grey matter of the aqueduct, are derived from the fillet of the olivary body. The nuclei of each side are connected by commissural grey ;Jiatter.

The superior bodies consist of a grey nucleus intersected by white longitudinal fibres.

THE THALAMENCEPHALON.

The third ventricle is the narrow space between the optic thalami, extending from the opening of the Sylvian aqueduct under the posterior commissur0, to the foramen of Monro. It is much deeper in front than behind.

The third ventricle communicates above by the Y-shaped foramen of Monro with the lateral ventricles and behind with the 4th ventricle by the aqueduct of Sylvius.

128 THE POCKET ANATOMY

Boundaries : —

Roof. Floor. Laterally.

Fornix. Lamina cinerea. Optic thalamus.

Velum interpositum with Optic commissure. Peduncles of pineal

choroid plexus of 3rd Tuber cinereum. gland,

ventricle. Infundibulum. j^-u_j

Corpora albicantia. Anteriorly.

Posteriorly. Posterior perforated Pillars of fornix.

Pineal gland. spot. Foramen of Monro.

Posterior commissure. Tegmenta of crura Anterior commissure.

Sylvian aqueduct. cerebri.

Commissures : the anterior commissure will be described with cerebral hemispheres.

The posterior commissure : is a commissural layer of white fibres connecting the two optic thalami posteriorly. It forms the posterior boundary of the 3rd ventricle, being placed just above the upper opening of the aqueduct of Sylvius, and beneath the pineal body.

The middle or soft commissure: a delicate band of grey matter passing between the optic thalami, near middle of ventricle.

The optic thalami. Two oblong masses of grey matter, covered with a thin layer of white fibres, the stratum zonale, and projecting above into the lateral ventricles.

Upper surface : there is a groove along this surface, running from behind obliquely forwards and inwards, which corre- sponds to the free lateral edge of the fornix and divides it into two pear-shaped pieces, the outer (ventricular area) having its base forwards and projecting in front, forming the anterior tubercle, and the inner (extra- ventricular area) having its base behind and to the inner side, which forms ihe posterior tubercle or pulvinar. This surface is separated from the mesial, or surface bounding the 3rd ventricle, by the peduncle of the pineal body; and between this and the pulvinar is a trian- gular depressed surface, the trigonum habenula. This surface is partly covered by the fornix resting on the velum inter- positum, and is separated externally from the caudate nucleus by the taenia semicircularis.

Posterior extremity is formed chiefly by the pulvinar. Below and outside this is the eminence of the outer geniculate body ; and just below this is the inner geniculate body, the brachium from the superior corpus quadrigeminum passing between them.

Under surface : placed on the tegtnentum of the crus.

External surface : fibres of the crusta (internal capsule) pass between this surface and the lenticular nucleus,.

THE BRAIN 129

Internal surface : forms lateral wall of 3rd ventricle, and is covered by ependyma.

Anterior extremity (anterior tubercle) : posterior boundary of foramen of Monro.

The pineal body is a cone-shaped body placed at the back of the 3rd ventricle, and overlying the superior quadrigeminal bodies. The 3rd ventricle projects backwards into its base or peduncle (pineal recess), which is thus divided into a dorsal part, connecting the pineal body on each side with the optic thalamus, and a ventral part, connecting it with the posterior commissure.

The posterior perforated spot is a depression containing grey matter placed at the base of the brain, in the angle of divergence of the crura. It is bounded by the corpora albi- cantia in front, and by the pons behind. The anterior part corresponds to the under portion of the floor of the 3rd ven- tricle, and is perforated for bloodvessels to the optic thalami.

The corpora albicantia are two small whitish bodies, placed in front of the posterior perforated spot and behind the tuber cinereum. They consist of grey matter covered with white fibres, derived from the anterior pillars of the fornix.

The tuber cinereum is an eminence of grey matter, situated in front of the corpora albicantia, and extending forwards to the optic tract. From its centre a tubular conical process of grey matter, the infundibulum, passes downwards and forwards to the posterior lobe of the pituitary body.

The pituitary body is a reddish-grey vascular mass lying in the sella turcica. It consists of two lobes, the anterior being the larger.

The optic commissure or chiasma is the union of the two optic tracts, and is placed in the middle line just in front of the tuber cinereum. From the anterior part the two optic nerves proceed.

Decussation of the nerve fibres. — When the fibres of the tract reach the commissure, they pass across for the most part to form the optic nerve of the opposite side, but a few pass directly into the nerve of the same side. The posterior fibres of the chiasma are described as simply passing between the two inner geniculate bodies.

The lamina cinerea is a layer of grey matter lying above the optic commissure, and passing from the extremity of the corpus callosum backwards to the tuber cinereum ; laterally it is connected with the grey matter of the anterior perforated spot, which lies under the anterior end of the corpus callosum and is pierced by vessels.

9

(30 THE POCKET ANATOMY

THE CEREBRAL HEMISPHERES.

The cerebral hemispheres form as a whole an oval mass, with the larger end backwards, and separated into two equal portions by the great longitudinal fissure. Each hemisphere presents three surfaces :

1. Outer : convex, occupying the vault of the cranium.

2. Inner : flat, forming one side of the longitudinal fissure.

3. Under: irregular, corresponding in shape to the anterior and middle fossae, and to the upper surface of the tentorium. It has a deep cleft, the fissure of Sylvius, between the portions occupying the anterior and middle fossae.

The surface of each hemisphere consists of grey matter, and is divided into convolutions or gyri by intervening sulci.

The great longitudinal fissure separates incompletely the two hemispheres, dividing them completely in front and behind ; but at the base near the middle they are united by the corpus callosum. The falx cerebri occupies the fissure.

The transverse fissure of the cerebrum is a cleft in the posterior part of the brain, which is seen when the velum interpositum and choroid plexuses of the lateral ventricles are removed. It extends from the tip of the descending cornu on one side, over the optic thalami, 3rd ventricle, and mesen- cephalon to the tip of the descending cornu on the other side.

The FISSURES of the Hemispheres, or Interlobar Sulci.

1. The fissure of Sylvius commences below at the outer side of the anterior perforated spot, passes upwards and out- wards between the frontal and temporo-sphenoidal lobes, and divides into two branches, an anterior or ascending, the shorter, passing into the frontal lobe, and a posterior or horizontal, passing behind the island of Reil, upwards and backwards to about the middle of the outer surface of the hemisphere.

2. The fissure of Rolando commences at the longitudinal fissure near the vertex, passes downwards and forwards nearly as far as the division of the Sylvian fissure. It separates the parietal and frontal lobes.

3. The parieto-occipital fissure consists of two portions, an internal or perpendicular fissure, seen on the inner surface of the hemisphere, and an external, extending on the outer surface, between the parietal and occipital lobes, for about an inch.

4. The calloso-marginal fissure commences in front near the anterior perforated spot, and takes a course on the inner surface of the hemisphere about midway between the corpus callosum and the edge of the longitudinal fissure, ending a little behind the upper end of the fissure of Rolando.

5. The collateral fissure lies along the lower border of the uncinate convolution ; it projects inwards and forms the

THE BRAIN 131

eminentia collateralis in the descending cornu of the lateral ventricle.

6. Limiting sulcus of Reil, round the island of Reil (p. 133).

THE LOBES.

The hemispheres are by the above fissures arbitrarily divided into seven lobes, viz. : —

1. Frontal: limited below by the Sylvian fissure, behind by the fissure of Rolando, internally by calloso-marginal fissure.

2. Parietal: limited in front by the fissure of Rolando, and behind by the parieto-occipital fissure ; below by fissure of Sylvius continued backwards, and internally by calloso- marginal fissure.

3. Occipital: Bounded in front by the parieto-occipitai fissure ; forms the posterior part of the hemisphere.

4. Temporo-sphenoidal : occupies middle fossa at the base of the skull, being placed behind the Sylvian fissure, and below the parietal and occipital lobes, internally separated from limbic lobe by collateral fissure.

5. Central or Island of Reil: contained in the Sylvian fissure ; triangular in shape.

6. Limbic or falciform: consists of caliosal and uncinate gyri, bounded above and in front by calloso-marginal and below by collateral fissures.

7. Olfactory : lying on the under surface of the frontal lobe, sometimes termed the olfactory nerve.

The frontal lobe :— Convolutions and sidci : — On Tinder surface : —

The tri-radiate or orbital sulcus divides this surface into an inner, anterior, and posterior or outer orbital convolutions. On the inner convolution is the olfactory sulcus, which contains the olfactory lobe. On outer surface : —

The ascending frontal or precentral convolution is bounded behind by the fissure of Rolando, round the lower end of which it joins the ascending parietal convolution ; in front by the precentral sulcus.

The longitudinal frontal convolutions are three in number, upper, middle, and inferior ; they occupy the rest of the outer surface and are separated from each other by two sulci, and from the ascending convolution by the precentral sulcus. On itmer surface : —

The marginal convolution extends along the edge of the longitudinal fissure. It commences at the anterior

0— 7

i32 THE POCKET ANATOMY

perforated spot, and is limited below by the calloso- marginal sulcus, and behind by its upturned extremity .

2. The parietal lohe : —

Convolutions and sulci : — On outer surface : —

The intra- parietal sulcus commences near posterior limb of Sylvian fissure, passes upwards parallel to the lower ha'f of the fissure of Rolando, and then turns backwards to end near parieto-occipital fissure.

The postcentral stilcus continues the line of the vertical part of the intra-parietal sulcus.

The ascending parietal convolution is bounded in front by the fissure of Rolando, behind by the intra-parietal and postcentral fissures, below by the fissure of Sylvius, and above it joins the superior parietal convolution.

The superior parietal convolution is bounded by the post- central fissure in front, behind by the parieto-occipital fissure, round which it is connected to the superior occipital convolution by the first anncctant gyrus.

Inferior parietal subdivided into : —

The supra-marginal convolution, bounded in front and above by the intra-parietal fissure, round the lower end of which it joins the ascending parietal convolu- tion ; behind by the posterior limb of the Sylvian fissure, round which it joins the superior temporo- sphenoidal convolution.

The angular convolution occupies the rest of the outer surface of the parietal lobe. Above is the superior parietal lobule, below the temporo-sphenoidal lobe, in front the supra-marginal gyrus, and behind the occipital lobe : it arches over the upturned end of the parallel sulcus, and is continuous with the second temporo- sphenoidal convolution. The postparietal convolution curves over the upturned second temporal sulcus, and is continued into the third temporo-sphenoidal con- volution. On the inner surface : —

The quadrate lobule lies anterior to the cuneate ; it is bounded behind by the internal parieto-occipital fissure, and in front by the ascending terminal limb of the calloso-marginal sulcus.

3. The occipital lobe : —

On outer surface three convolutions, an upper, a middle, and an inferior, by two sulci.

The superior occipital convolution is connected anteriorly to the 6-H.perior parietal lobule by the first annectant gyrus.

THE BRAIN 133

The middle occipital convolution joins the angular convolution by the second annectant gyms, and to the middle temporo- sphenoidal convolution by the third annectant gyrus.

The inferior occipital convolution is connected to the inferior temporo - sphenoidal convolution by the fourth annectant gyrus.

On inner surface : —

The cuneate lobule is the area between the internal parieto- occipital and the calcarine fissures.

The calcarine fissure commences at the posterior part of the inner surface of the occipital lobe by a forked extremity ; is joined about half-way by the internal parieto-occipital fissure, and ends near the posterior extremity of the corpus callosum.

On under surface : —

The inferior occipito-temporal convolution lies just below the collateral fissure, and extends from the apex of the temporo- sphenoidal lobe to the posterior part of the hemisphere, form- ing the under surface of both temporal and occipital lobes.

4. The temporo-sphenoidal lobe : — On outer surface : —

The superior temporo-sphenoidal or parallel sulcus runs parallel to posterior limb of the Sylvian fissure.

The middle temporo - sphenoidal sulcus lies parallel to the superior.

The superior temporo-sphenoidal convolution (infra-marginal) is bounded above by posterior limb of Sylvian fissure, and con- tinuous behind with supra-marginal convolution.

The middle temporo-sphenoidal convolution joins posteriorly the angular, and by the third annectant gyrus merges into the middle occipital convolution.

The inferior temporo-sphenoidal convolution joins the inferior occipital convolution by the fourth annectant gyrus.

On under surface : —

Inferior occipito-temporal convolution in its anterior part.

5. The central lobe or island of Reil lies in the fissure of Sylvius at the base of the brain. Boundaries : In front, the anterior sulcus of Reil, which separates it from the posterior orbital convolution. Superiorly, the superior sulcus of Reil, separating it from the gyri of the operculum, a collective name given to the portions of the inferior frontal, and lower ends of the ascending frontal and parietal convolutions which lie between the ascending and posterior limbs of the Sylvian fissure. Posteriorly, by the posterior sulcus of Reil, separating it from the temporo-sphenoidal lobe. It is divided by the central sulcus into an anterior part, which is subdivided into

I34 THE POCKET ANATOMY

three gyri breves, and a posterior part subdivided into two gyri longi.

6. The limbic lobe :

On the inner surface consists of : —

The gyrus fornicatus or callosal convolution lies beneath the marginal convolution, being separated from it by the calloso- marginal sulcus. It commences near the anterior perforated spot, follows the curves of the corpus callosum, near the posterior end of which it becomes continuous with the uncinate gyrus.

The uncinate convolution (hippocampal) commences below the splenium of the corpus callosum ; here the end of the calcarine fissure cuts into it, leaving a narrow isthmus con- necting it with the callosal convolution. It runs forwards above the collateral fissure into the temporal lobe and ends as the uncus.

The dentate sulcus (hippocampal) lies along the upper border of the uncinate convolution, and forms the hippocampus major in the descending cornu of the lateral ventricle.

The dentate convolution (fascia dentata) lies in the dentate fissure, It is formed by the superficial grey matter of the hemisphere, which here ends in a fringed margin.

7. The olfactory lobe extends from the anterior perforated spot as the olfactory tract, and ends in an enlargement, the olfactory bulb. It lies in the olfactory sulcus on the orbital surface of the frontal lobe. Posteriorly the tract bifurcates, the outer root passing across commencement of Sylvian fissure to the uncinate convolution, and the inner one to the great longitudinal fissure to join the callosal convolution.

THE INTERIOR OF THE CEREBRUM.

The centrum ovale minus is the central white mass in each hemisphere seen on horizontal section, the section being made about £ inch above the corpus callosum.

The centrum ovale majus, seen on section at the level of the corpus callosum, is the centrum ovale minus of each side, joined by the corpus callosum.

The corpus callosum lies at the bottom of the great longi- tudinal fissure. It is the great transverse commissure of the hemispheres, and consists principally of transverse fibres.

Length. — About 4 inches, extending to within i£ inches of the anterior, and 2$ inches of the posterior extremities of the hemispheres.

Shape. — Broader behind than in front, thicker at each end

THE BRAIN 135

than at the middle, and thickest behind. It terminates pos- teriorly in a free, thickened border, the splenium ; in front it curves down towards the base of the brain, the bend being known as the genu, and the reflected part as the rostrum.

Raphe : the longitudinal eminence along the centre of the upper surface.

Nerves of Lancisi (striae longitudinales) : longitudinal white fibres placed on each side of the raphe.

Covered band of Reil : longitudinal fibres outside the nerves of Lancisi, under cover of the convolution of the corpus callosum.

Relations. — Upper surface forms floor of great longitudinal fissure ; under surface connected behind with the fornix, and in front of this with the septum lucidum. The extremity of the rostrum is connected centrally with the lamina cinerea, and laterally with two white bands, the peduncles of the corpus callosum, which pass backwards and outwards over the anterior perforated spot towards the Sylvian fissure to the anterior extremity of the temporal lobes. Traced upwards, these fibres are continuous with nerves of Lancisi The corpus callosum roofs in the bodies and anterior cornua of the lateral ventricles.

The lateral ventricles are two in number, one in each hemisphere. They communicate below and in front with one another and with the 3rd ventricle by the foramen of Munro. Each ventricle consists of a body or central cavity, and three cornua, anterior, posterior, and descending.

Relations of the body : — Roof. — Corpus callosum.

Internal wall. — Septum lucidum and the fornix. Floor. — From before backwards.

1. Caudate nucleus of corpus striatum.

2. Tasnia semicircularis.

3. Part of optic thalamus in front of choroid plexus.

4. Choroid plexus of lateral ventricle.

5. Fimbriated edge of the fornix.

The anterior cornu is the anterior end of the ventricle which curves outwards round the caudate nucleus. Relations : —

In Front. Roof. Floor and Externally. Internally

Genu of corpus Corpus callosum. Caudate nucleus. Septum 1« callosum. dum.

The posterior cornu projects backwards and inwards into tfc occipital lobe.

'36	THE POCKET ANATOMY
Relations : —
Roof and Outer Wall.	Floor.	Inner Wall.	At Junction o/ Posterior and De*
			scending Cornua.
Fibres of corpus callosum pass- ing to temporo- sph eno id al	White substance of occipital lobe.	Hippocam- pus minor, formed by the calcar-	Eminentia collater- alis, formed by the inward pro- jection of the col-
lobe.		ine sulcus,	lateral sulcus.
		projecting inwards.

The descending cornu passes at first backwards and outwards round the posterior part of the optic thalamus, then down- wards, forwards and inwards.

Relations : —

Roof. Floor. Inner Wall. Outer Wall.

Fibres of corpus Hippocampus Pia mater. White substance

callosum pass- major. of the hemi-

ing to temporo- Tzenia hippocampi. sphere.

sphenoidal lobe. Choroid plexus. Amygdaloid tu- Eminentia collator-

bercle. alis.

Tail of caudate

nucleus.

The hippocampus major : a large white projection in the whole length of the floor of the descending cornu. It corre- sponds with the dentate sulcus. The anterior extremity becomes enlarged and indentated, forming the pes hippocampi.

Tcenia hippocampi or fimbria of the fornix : a narrow white band prolonged from the posterior pillar of the fornix, and lying along the inner margin of the hippocampus major.

The septum lucidum is a double vertical partition between the lateral ventricles, attached to the fornix and rostrum below, and to the under surface of the body of the corpus callosum above. Between the layers is the 5th ventricle, a closed narrow space, having no connection with the other ventricles, and not lined by ependyma.

The fornix consists of two white longitudinal strata beneath the corpus callosum, separated in front and behind, forming the pillars, but joined in the middle, forming the body.

The body is triangular in shape, the base being placed pos- teriorly, and here connected with the corpus callosum. In front of this it is connected with the septum lucidum along its upper surface. The lateral margins are free, lying against the choroid plexus of the lateral ventricles. The under surface lies upon the velum interpositum.

The anterior pillars pass downwards, forming the anterior

THE BRAIN 137

boundary of the foramen of Monro, then through the grey matter on the outer side of the 3rd ventricle ; and on reaching the base of the brain they make a half figure-of-eight turn, forming the white envelope of the corpora albicantia ; they then ascend and pass into the anterior nucleus of the optic thalamus. The pillars receive near the foramen of Monro the fibres of the peduncles of the pineal gland, and those of the taenia semicircularis.

The posterior pillars : the two strata of the fornix diverge behind, being connected at first with the splenium of the corpus callosum ; thence curving round the pulvinar they pass into the descending cornu, the outer fibres being lost on the hippocampus major, the inner ones forming the taenia hippocampi.

Between the diverging posterior pillars a portion of the splenium with transverse markings is exposed ; this is known as the lyra .

The foramen of Monro is the interval between the anterior pillars of the fornix and the optic thalami. It is Y-shaped, the two limbs anteriorly communicating with the lateral ventricles on either side, and the junction of the two opening into the 3rd ventricle.

The velum interposition is a triangular process of pia mater prolonged through the transverse fissure and lying over the 3rd ventricle and upper surfaces of the optic thalami. Its apex reaches the foramen of Monro, and the fornix lies upon its upper surface.

Choroid plexuses : —

Of the lateral ventricles are fringed vascular processes extend- ing from the foramen of Monro to commencement of descend- ing cornu, and attached along the lateral margins of the velum interpositum ; thence each passes into the descending cornu, resting on the taenia hippocampi and hippocampus major, forming the choroid plexus of the descending cornu.

Of the yd, ventricle: from the under surface of the velum interpositum there depend two vascular fringes, diverging behind, and forming the choroid plexus of 3rd ventricle.

Veins of Galen : two veins formed by junction of the vein of the corpus striatum and choroidal vein of each side, and running backwards between the layers of the velum inter- positum, and uniting posteriorly into one trunk, which opens into the straight sinus.

The corpora striata, so called from their appearance on section, which displays alternate white and grey bands, are two in number, one in each hemisphere, and are sometimes termed the ganglia of the hemisphere. Each consists of an

138 THE POCKET ANATOMY

ovoid mass of grey matter lying outside and in front of the optic thalamus. The largesfpart (lenticular nucleus) lies in the white matter of the hemisphere outside the lateral ventricle, and a smaller part (caudate nucleus) appears in the floor of that space.

The caudate nucleus is pear-shaped, with the larger end placed anteriorly, occupying the floor and outer wall of the anterior cornu ; the narrow posterior part lying along the floor and outer wall of the lateral ventricle passes into the roof of the descending cornu, where it is joined by the taenia semi- circularis to form the amygdaloid tubercle.

The lenticular nucleus lies outside and at a lower level than the caudate nucleus, from which it is separated by a layer of white fibres, the internal capsule. Outside the nucleus is another stratum of white fibres, the external capsule, and beyond this a thin lamina of grey matter called the claustrum, the outer surface of which lies next to the white substance of the island of Reil.

The taenia semicircularis is a narrow band of white fibres attached to the anterior pillar of the fornix in front, whence it passes backwards in the floor of the lateral ventricle, between the caudate nucleus and the optic thalamus ; it then passes into the roof of the descending cornu, at the end of which it enters a mass of grey matter, the nucleus amygdala, continuous with the superficial grey matter at the apex of the temporo- sphenoidal lobe, and placed just under the lenticular nucleus.

The anterior commissure is a bundle of white fibres lying in the anterior part of the 3rd ventricle, in front of the anterior pillars of the fornix. The fibres go through the caudate nucleus, and, passing under the lenticular nucleus, ultimately enter the temporo-sphenoidal lobe.

SYNOPSIS OF COURSE OF FIBRES IN THE CENTRAL HEMISPHERES.

i . Peduncular fibres, connecting cord and cerebellum with cerebrum : —

(a) From crusta, chiefly through internal capsule to

convolutions.

(b) From tegmentum, chiefly to optic thalamus ; a part

joins the inner capsule, and passes to occipital

and temporo-sphenoidal lobes.

The peduncular fibres, in their course to the convolutions, are reinforced by fibres from the corpora striata and optic thalami.

THE BRAIN 139

2. Transverse fibres, connecting the two hemispheres : —

(a) Of corpus callosum.

(b) Anterior commissure.

3. Collateral fibres, connecting different parts of the same hemisphere.

(a) Fornix.

(b) Ttenia semicircularis.

(c) Nerves of Lancisi.

(d) Gyrus fornicatus, the fibres of which are said to

encircle the corpus callosum, near the middle line, meeting at the anterior perforated space.

(e) Uncinate fasciculus, a white bundle at the bottom

of the Sylvian fissure, uniting the frontal and

temporo-sphenoidal lobes. (/) Inferior longitudinal fasciculus, a collection of fibres

passing between temporo-sphenoidal and occipital

lobes. (g) Association fibres, passing between and connecting

together the different convolutions.

THE MEMBRANES OF THE BRAIN, OR MENINGES.

The DURA MATER, the most external, is a dense fibrous membrane, which is closely attached to the bones of the skull, forming their internal periosteum. The inner surface is smooth, and covered with endothelium. It is continuous with the dura mater of the spinal cord through the foramen magnum. The fibrous part of the dura mater is divided into two layers, an outer, forming the periosteum, and an inner, lying under the endothelium, forming certain processes, and which, by its separation in certain situations, forms the sinuses (for sinuses of dura mater, vide p. 97). On the upper surface, near, and projecting into the longitudinal sinus, are the Pacchionian bodies, which are enlarged villi of the arachnoid projecting through the layers of dura mater.

Processes of the dura mater : —

The falx cerebri : placed vertically between the two hemi- spheres of the cerebrum, attached in front to the crista galli, behind to the upper surface of the tentorium, and between these above to middle line of internal surface of skull, while the lower border is concave and free. In relation with it are the superior and inferior longitudinal, and the straight sinuses.

The tentorium cerebelli is a crescentic fold of dura mater placed between the cerebrum and the cerebellum. It has an outer convex border, by which it is attached in front to the

140 THE POCKET ANATOMY

posterior clinoid processes, superior edge of the petrous bone, and behind to the margins of the groove for the lateral sinus. The inner concave border is free posteriorly, and forms the opening through which the crura cerebri and the posterior cerebral arteries pass from the posterior into the middle cranial fossa ; in front this border passes over the attached border, and is attached to the anterior clinoid processes. The tentorium is a tent-like process, highest above and in front, at its most anterior point of attachment of the falx cerebri by which the tentorium is suspended, and from this point descending on all sides. In relation to it are the lateral, superior petrosal, and straight sinuses.

The falx cerebelli reaches vertically from the tentorium to the foramen magnum, dividing the two hemispheres of the cerebellum. It is attached posteriorly to the vertical crest of the occiput, where it encloses the occipital sinus, and below to each side of the foramen magnum.

The PIA MATER consists of a delicate stroma supporting bloodvessels, and closely invests the brain, dipping into the sulci. At the transverse fissure it is prolonged into the lateral ventricles and over the 3rd ventricle, pushing the endothelial lining of those cavities in front of it, and forming the velum interpositum and choroid plexuses of the lateral and 3rd ven- tricles. It is prolonged over the roof of the 4th ventricle, sending inwards two vascular fringes, the choroid plexuses of that cavity.

The ARACHNOID is a thin membrane lying outside the pia mater, but is not so closely applied to the brain, as it passes over the sulci without dipping into them. Between the pia mater and the arachnoid is the subarachnoid space, containing the subarachnoid fluid. The space between the dura mater and arachnoid is now known as the subdural space.

The subarachnoid space is larger in some places than in others. The arachnoid stretches across between the two middle lobes at the base of the brain, forming the cisterna basalis, which lies anterior to the pons and reaches as far forward as the optic nerves. Beneath the cerebellum it forms in a like manner the cisterna magna, by stretching between the under surface of the cerebellum and the posterior surface of the medulla.

At the bottom of the longitudinal fissure the subarachnoid space is also large.

The subarachnoid space communicates with the cerebral ventricles by the foramen of Majendie, an opening into the

NERVES 141

4th ventricle in the expansion of pia mater across the roof. There are two other openings through the pia mater, placed one on each side of the upper roots of the glosso-pharyngeal nerve, under the flocculus.

THE NERVES.

THE NERVES OF THE HEAD AND NECK.

THE CRANIAL NERVES, 12 pairs.

IST or OLFACTORY. Course: the olfactory tract passes forwards on the under surface of the frontal lobe near the longitudinal fissure, resting on cribriform plate and expanding anteriorly into olfactory bulb. There is an enlargement at the posterior part of the upper surface called the olfactory tubercle.

Distribution. — About twenty nerve filaments are given off from under surface of the olfactory bulb (p. 134), and pass downwards through ethmoidal foramina; they are divided into three sets to supply Schneiderian membrane of the nose ; inner to septum, middle to roof of nose, outer to superior and middle turbinate bones.

Special function. — Smelling.

2ND or OPTIC. Origin, from optic tract, which arises by two roots : Outer, from external geniculate body, optic thalamus and brachium of superior quadrigeminal body. Inner, from internal geniculate body.

Course. — Winds across outer and anterior surfaces of crus cerebri, uniting with fellow to form optic commissure, which is bounded in front by the lamina cinerea and behind by the tuber cmereum ; the nerves separate at fore part of commis- sure, get ensheathed in arachnoid, and pass into orbit through optic foramen above and internal to ophthalmic artery ; whilst passing through, each receives a tube of dura mater, which divides into two, the outer piece becoming orbital periosteum, and the inner, ensheathing the nerve, joins the sclerotic in front. The nerve pierces sclerotic and choroid coats of eyeball.

Distribution. — Expands to form innermost layer of retina.

Special function. — Nerve of sight.

3RD or MOTOR OCULI. Superficial origin : inner side of crus cerebri, just in front of pons. Deep origin : floor of aqueduct of Sylvius.

Course. — Pierces dura mater to enter canal in outer wall of

i4« THE POCKET ANATOMY

cavernous sinus near posterior clinoid process, lying above and internal to 4th nerve. As it passes forwards to enter orbit through sphenoidal fissure, the 4th nerve and frontal branch of 5th cross externally and become superior to it. It divides into two branches in the fissure, which enter orbit between the heads of the external rectus, the nasal branch of the 5th lying between the two ; whilst in cavernous sinus it communicates with cavernous plexus.

Distribution. — Superior branch supplies superior rectus and levator palpebrae superioris. Inferior divides into three, for internal rectus, for inferior rectus, and for inferior oblique, which latter gives off short or motor root to the lenticular ganglion, through which the 3rd nerve supplies the ciliary muscle and the sphincter fibres of the iris.

Special function. — Motor nerve of eyeball.

4TH or TROCHLEAR. Origin — Superficial : valve of Vieussens, just behind corpora quadrigemina. Deep : floor of aqueduct of Sylvius.

Course. — Winds round outer surface of crus cerebri and pierces free border of tentorium ; passes forwards in outer wall of cavernous sinus below 3rd, but enters orbit through sphenoidal fissure above and internal to the other nerves and external rectus.

Distribution. — Enters orbital surface of superior oblique.

Special function. — Motor nerve of superior oblique.

5TH or TRIFACIAL. Origin — Superficial : from the side of the pons, by small motor and large sensory roots, the latter having a ganglion on it. Deep : Sensory : (a) floor of 4th ventricle ; (6) (ascending root), posterior horn of grey matter of medulla, and upper part of cord. Motor: (a] floor of 4th ventricle ; (b) (descending root), side of aqueduct of Sylvius.

Course. — The two roots pass forwards through oval opening in dura mater near apex of petrous bone, the sensory root entering the Gasserian ganglion, lodged on the apex of petrous part of temporal bone. The motor root passes under ganglion and is not connected with it, but goes through foramen ovale uniting with the Inferior Maxillary division.

The Gasserian ganglion : lodged in a depression (Meckel's cave) near the apex of petrous part of temporal, gives off from its anterior edge the ophthalmic, superior maxillary, and inferior maxillary trunks. The two former are purely sensory ; the last by joining small motor root becomes a mixed nerve.

OPHTHALMIC or ist division of the 5th (sensory and smallest branch) : courses along outer wall of cavernous sinus below 3rd and 4th nerves, to enter orbit through sphenoidal fissure.

NERVES 143

In sinus communicates with cavernous plexus and third, fourth, and sixth nerves, and divides into three branches, two of which, frontal and lachrymal, enter orbit above external rectus, whilst the third or nasal passes between two heads of origin of that muscle, and between two divisions of 3rd nerve.

Branches : —

Lachrymal : passes along outer wall of orbit to under sur- face of lachrymal gland, communicates with orbital of superior maxillary, finally pierces palpebral fascia, and sup- plies skin of upper eyelid, inosculating with branches of facial.

Frontal : largest branch, enters orbit just outside 4th nerve, passes forward on levator palpebrae, and divides into : —

Supra -trochlear : directed forwards and inwards between pulley and supra-orbital notch ; distributed to forehead and communicates with infra-trochlear.

Supra-orbital : continuation of frontal, passes through notch, supplies palpebral filaments, and ends on forehead by dividing just outside orbit into two branches, of which the external is the larger. It supplies the scalp. Communicates with facial.

Nasal : enters orbit between the heads of the external rectus, passes forwards and inwards over optic nerve along inner side of orbit, through anterior ethmoidal foramen ; re-entering cranium, it passes down nasal slit by the side of the crista galli, dividing into two terminal branches, viz : —

Internal : supplying mucous membrane of the septum.

External : runs along groove on internal surface of nasal bone, then passes between bone and lateral cartilage to supply skin of ala, and tip of nose. Communicates with facial.

Branches from nasal in the orbit : —

Ganglionic : arises between heads of external rectus, passes along outer side of optic nerve, entering the posterior superior angle of lenticular ganglion, of which it forms the long or sensory root.

Long ciliary (2 or 3) pass along inner side of optic nerve, join some short ciliary branches from ganglion, and, piercing sclerotic, are distributed to ciliary body and iris.

Infra-trochlear : given off as nerve enters anterior ethmoidal foramen ; it passes to inner angle of orbit, communicating beneath ' pulley ' with the supra- trochlear of frontal. It sup- plies lachrymal sac, skin of eyelids and root of nose.

The LENTICULAR GANGLION is a small reddish-coloured body, placed between the optic nerve and the external rectus, •at the back part of the orbit.

»44 THE POCKET ANATOMY

Branches of communication or roots : —

Long or sensory root : from the nasal of the ophthalmic, joins posterior superior angle.

Short or motor root : from the branch of the 3rd nerve sup- plying inferior oblique, joins posterior inferior angle.

Sympathetic : from the cavernous plexus, and frequently joined with the long or sensory root.

Branches of distribution : —

Short Ciliary Nerves : Ten or twelve given off in two bundles, large inferior and small superior. Pass forwards above and below optic nerve, with long ciliary of nasal. The branches subdivide and, piercing sclerotic, run in grooves on its internal surface 10 end in ciliary muscle and iris. The circular fibres of the iris and the ciliary muscle are innervated by the third nerve, the radial fibres of the iris by the sympathetic.

The SUPERIOR MAXILLARY NERVE (sensory) passes from the middle of the Gasserian ganglion through foramen rotundum, then across spheno-maxillary fossa to enter the infra-orbital canal, and here receives the name of infra- orbital. Emerging on the face from the infra-orbital foramen under the levator labii superioris, it divides into a number of branches, nasal, palpebral and labial, and joins with branches of the facial nerve to form the infra-orbital plexus.

Branch in the Skull : —

Recurrent : given off near origin to dura mater.

Branches given of in the Spheno -maxillary fossa : —

Orbital ortemporo-malar: enters orbit by spheno-maxillary fissure and directly divides into : —

Temporal: passes along groove in oufer wall of orbit, here communicating with the lachrymal : it then goes through a foramen in the malar bone, and, entering the temporal fossa, passes anterior to the temporal muscle : piercing the temporal aponeurosis, it becomes cutaneous, and inosculates with branches from the facial nerve.

Malar: passes to lower and outer angle of orbit, goes through malar foramen, and communicating with the facial becomes cutaneous.

Spheno-palatine (2) descend to Meckel's ganglion.

Posterior superior dental: comes off just before nerve enters canal, and divides into : —

External branch : passes downwards to the 'gums.

Internal branch : enters a canal in the superior maxilla, and runs along outer wall of antrum ; supplies the molar teeth and mucous membrane of the antrum. Communicates with middle superior dental.

NERVES 145

Branches arising within the infra-orbital canal : —

Middle and anterior superior dental : descend in canals in anterior wall of antrum, and divide into branches.

The anterior supplies incisor and canine teeth.

The middle supplies the bicuspid teeth.

Branches arising on the face : —

Inferior palpebral: supplies integument of lower eyelid, communicating with facial, and rnalar of orbital.

Nasal : to integument of side of nose. Joins nasal of ophthalmic.

Labial : three or four branches to integument of upper lip.

The SPHENO-PALATINE or MECKEL'S GANGLION is deeply placed in the spheno-maxillary fossa, near the spheno-palatine foramen.

Roots :—

Motor from the facial. (Large superficial petrosal nerve.)

Sympathetic from the carotid plexus. (Large deep petrosal nerve.) See Vidian nerve, p. 146.

Sensory from the superior maxillary. (Spheno-palatine nerves.)

Branches of distribution : —

Ascending : three or four small branches to the periosteum of the orbit.

Descending : mostly continuous with spheno - palatine of superior maxillary nerve.

The anterior or large palatine nerve passes through large posterior palatine canal to hard palate, there dividing into branches which run forward in grooves in the bone nearly to the incisor teeth, joining the naso-palatine nerve in the region of anterior palatine canal. It supplies the gums and mucous membrane of hard palate. Whilst in the posterior palatine canal it gives off the inferior nasal branches which supply mucous membrane on middle and inferior spongy bones.

The posterior or small palatine nerve enters smaller posterior palatine canal to supply mucous membrane of soft palate, uvula and tonsil.

The external palatine nerve passes through external palatine canal to the tonsil and soft palate.

Internal.

Superior nasal (4 or 5) through spheno-palatine foramen to supply the posterior and upper part of the superior meatus.

The naso-palatine nerve (nerve of Cotunnius) passes inwards through spheno-palatine foramen, crosses roof of nasal fossa to septum, on which it passes downwards and forwards with its fellow of the opposite side to the foramina of Scarpa in anterior palatine canal, the left nerve being anterior, and,

10

146 THE POCKET ANATOMY

communicating with the large palatine nerve, ends in the gums of the incisor teeth. Branches are given to the mucous membrane over the septum.

Posterior.

The Vidian nerve, really formed by two roots of the ganglion, passes backwards through Vidian canal, here giving off the upper posterior nasal branches to the back part of the roof of the nose. On emerging from the canal it divides in the foramen lacerum medium into a large deep petrosal nerve, which joins the sympathetic on the carotid artery, and a large superficial petrosal nerve, which runs along a groove on the petrous bone to the hiatus Fallopii, and, passing into the Fallopian aque- duct, joins the geniculate ganglion on the facial nerve. As the motor root of Meckel's ganglion, it may be traced forwards from facial nerve.

Thepharyng al nerve, which may come off from the ganglion, or from the Vidian nerve, enters pterygo-palatine canal and ends in the mucous membrane of the palate, near the Eustachian tube.

The INFERIOR MAXILLARY NERVE is the largest of the three divisions of the 5th. The large sensory root comes from the inferior angle of the Gasserian ganglion, which root is joined on its deep aspect near or in the foramen ovale by the small motor root from the trunk of the 5th nerve. The united nerve leaves skull by foramen ovale, and immediately divides into anterior and posterior trunks.

Branches from the trunk : —

Recurrent : passes backwards with the middle meningeal artery, through foramen spinosum, to supply dura mater.

Internal pterygoid : to deep surface of internal pterygoid, connected near origin with otic ganglion.

Branches from the anterior (small and chiefly motor} division: —

Masseteric : passes outwards with posterior deep temporal nerve above external pterygoid, then over sigmoid notch with artery, to deep surface of masseter and gives twigs to temporo- maxillary joint.

Deep temporal (3) : anterior, from the buccal nerve, to supply front of temporal muscle; middle, passes above external ptery- goid to deep part of temporal muscle ; posterior, often united with masseteric nerve, to back part of temporal muscle.

Buccal (sensory) : comes out between heads of external pterygoid to reach buccinator, and is frequently joined to the anterior temporal and external pterygoid nerves ; com- municates with facial, and is distributed to mucous membrane and skin of cheek.

NERVES 147

External pterygoid : to external pterygoid (generally given off from buccal) .

Branches from the posterior (large and chiefly sensory) division : —

The auriculo-temporal nerve comes off by two roots, be- tween which the middle meningeal artery passes ; runs back- wards under external pterygoid muscle, round temporo-maxil- lary capsular ligament, then upwards, with superficial temporal artery, beneath parotid to temporal fossa, where it becomes cutaneous, and lies posterior to superficial temporal artery.

Branches of the Auriculo-temporal : —

Inferior auricular : to ear below meatus.

Superior auricular : to integument of tragus, pinna, and to membrana tympani.

Communicating : to otic ganglion and facial.

Superficial temporal : to scalp with artery, joins temporal branches of facial.

Parotid : to gland.

Temporo-maxillary : to joint.

The inferior dental nerve passes down internal to externa: pterygoid muscle, and posterior to the lingual nerve ; then between the ramus of jaw and internal lateral ligament, to the inferior dental foramen, along which canal it runs at first anterior and then above the dental artery. It supplies the molar and bicuspid teeth, and emerges at the mental foramen, having just previously divided into two branches, one of which (incisor) is continued in the bone, and the other (mental) it-, continued over the chin.

Branch before entering the dental foramen : —

Mylo-hyoid : descends in a groove on the inner side of ramus of jaw to outer side of mylo-hyoid muscle, supplying it and giving a branch to the anterior belly of the digastric.

Branches given off in the dental canal : —

Dental: to molars and bicuspids.

Incisor: to canine and incisors.

Mental: passes out ol mental foramen, and divides into branches which supply integument of chin and lower lip, and communicate with the facial.

The gustatory or lingual nenr* lies at first internal to the external pterygoid muscle ; it then passes downwards in front of the inferior dental nerve, and is joined at an acute angle by the chorda tympani from the facial. Thence it passes down- wards and forwards between internal pterygoid and ramus, over the superior constrictor of the pharynx and on the hyo- glossus above the deep part of submaxillary gland, to the

10 — 2

1 48 THE POCKET ANATOMY

side of the tongue, and, crossing Wharton's duct externally, is continued to the tip of the tongue

Branches : —

Communicating: with inferior dental at commencement ; with facial through chorda tympani ; branches are sent also to submaxillary ganglion and the hypoglossal nerve.

Distributary: to mucous membrane of sides and tip of tongue, the gums and sublingual gland, the terminal branches supply- ing anterior f of mucous membrane of dorsum.

The SUBMAXILLARY GANGLION lies between the hyoglossus muscle and the deep part of the submaxillary gland.

Roots : —

Motor and sensory : the connecting branch from the lingual supplies sensory and motor from the facial, through the chorda tj'mpani.

Sympathetic : from plexus round facial artery.

Branches : —

Five or six small twigs supply the submaxillary gland, the mucous membrane, and Wharton's duct.

The OTIC GANGLION (Arnold's) lies on the inner surface of the inferior maxillary nerve, close to the foramen ovale, and is connected with the commencement of the nerve to the internal pterygoid muscle.

Roots :—

Motor and sensory: from the inferior maxillary, by the branch to the internal pterygoid.

Sympathetic : from plexus on middle meningeal artery, which lies just behind it.

The small superficial petrosal nerve passes into the posterior part of the ganglion connecting it with the facial and glosso- pharyngeal nerves.

Branches : —

Communicating: to auriculo- temporal, and to chorda tym pani.

Muscular: to the tensor tympani, and tensor palati.

SYNOPSIS OF THE FIFTH NERVE.

BRANCHES.

Ophthalmic.

Recurrent. Lachrymal :

Lachrymal. Palpebral.

NERVES 149

Ophthalmic (continued) : Frontal :

Supra-orbital. Supra-trochlear Na sal :

Ganglionic.

Long ciliary.

Infra-trochlear. f

Nasal, internal and external .

Superior Maxillary. Recurrent. Orbital :

Malar. . i

Temporal. Spheno-palatine. Posterior superior dental. Middle and anterior superior dental. Infra-orbital. Inferior palpebral. Nasal. Labial.

In'erior Maxillary. Recurrent. Internal pterygoid. Anterior, small or motor part : Deep temporal. Masseteric. Buccal (sensory). External pterygoid. Posterior, large or sensory part. Auricula -temp oval :

Auricular, inferior and superior. Parotid.

Temporal, superficial. Temporo-maxillary. Communicating. Inferior dental :

Mylo-hyoid (motor). Dental. Mental. Incisor. Lingual :

Communicating to inferior dental, sub- maxillary ganglion, and hypoglossal. Distributory to tongue.

150 THE POCKET ANATOMY

GANGLIA IN CONNECTION WITH THE 5TH NERV* Lenticular Ganglion. Roots :

From nasal. From 3rd nerve. From sympathetic. Branch of Distribution : Short ciliary nerves.

Meckel's Ganglion.

Roots :

Facial. \Vidian,

Carotid plexus. J

Superior maxillary. Internal Branches :

Nasal.

Nasopalatine. Ascending :

Orbital. Descending :

Large palatine.

Small palatine.

External palatine. Posterior :

Superior nasal.

Pharyngeal.

Submaxillary Ganglion,

Roots :

Lingual.

Chorda tympani.

Sympathetic. Distributary :

To gland, etc.

Otic Ganglion.

Roots :

Inferior maxillary.

Sympathetic.

Small superficial petrosal. Branches :

To auriculo-temporal.

Chorda tympani.

To Tensor tympani.

To Tensor palati.

NERVES 151

The 6xH or ABDUCENS OCULI. Origin — Superficial: from the sulcus between the pons and medulla, anterior to the anterior pyramid. Deep : floor of 4th ventricle beneath fasciculus teres.

Course.— Pierces dura mater on basilar process and grooves side of dorsum ephipii to reach cavernous sinus; lies to outer side of internal carotid, and below the other nerves. Enters orbit by sphenoidal fissure, between the heads of the external rectus, lying above ophthalmic vein.

Distribution. — External rectus (ocular surface).

Relations. — The following table shows how the nerves of the orbit change their position to one another. They lie from above down.

In ^Cavernous /w ^ sphenoidal Fi,sure.

Third. Fourth. Frontal. Lachrymal. Fourth. (Above the muscles.)

Fifth. Superior division o

Sixth

The 7TH or FACIAL. Origin — Superficial : from the pons, ex- ternally and posteriorly, on its ventral surface. Deep : floor of 4th ventricle, anterior and external to nucleus of 6th nerve.

Course. — Passes forwards and outwards to enter the internal auditory meatus ; it lies upon a groove on the auditory nerve, with pars intermedia of Wrisberg between, and at the bottom of the meatus the latter joins the facial, which entering the aqueductus Fallopii, runs first outwards above and between cochlea and vestibule as far as hiatus Fallopii ; then backwards in internal wall of tympanum, just above fenestra ovalis, at the bend presenting a swelling, the geniculate ganglion ; and finally it passes downwards, to emerge from the bone at the stylo-mastoid foramen ; it then passes outwards and forwards in the parotid, dividing behind the ramus of jaw into temporo-facial and cervico-facial branches, which further subdivide and intercommunicate, forming the pes anserimis.

Communications : —

In the meatus, with auditory and pars intermedia.

In the aqueduct, with Meckel's ganglion by large superficial petrosal ; otic ganglion by small superficial petrosal ; plexus on middle meningeal by external superficial petrosal.

152 THE POCKET ANATOMY

At exit from foramen, with pneumogastric, glosso-pharyngeal, carotid plexus, great auricular, auriculo-temporal.

On the face, with the three divisions on the $th.

Branches within the Aqueduct : —

Communicating from the geniculate ganglion tc the audi- tory.

Large superficial petrosal passes from geniculate ganglion through hiatus Fallopii, then through foramen lacerum medium to Vidian canal, where it joins the large deep pe- trosal to form the Vidian nerve (vide p. 146).

Communicating with the small superficial petrosal nerve (vide pp. 148 and 154).

External superficial petrosal : from geniculate ganglion to plexus on middle meningeal artery.

Tympanic : to the stapedius.

Chorda tympani : given off just before exit from stylo- mastoid foramen, ascends to tympanum through iter chorda posterius; it courses then between membrana tympani and base of pyramid, and between handle of malleus and long process of incus ; it leaves tympanum by iter chorda anterius, and, passing through Huguier's canal, emerges at the inner end of the Glaserian fissure, then forwards between two pterygoids to join gustatory or lingual. It forms the sensory root of submaxillary ganglion, and ends in the tongue.

Communicating with the auricular branch (Arnold's nerve) of the pneumogastric.

Branches given off at exit from Foramen : —

Posterior auricular : passes up behind and between mastoid process and meatus, dividing into auricular to supply retrahens and attollens aurem, and occipital to posterior belly of occipito- frontalis; communicates with auricular of pneumogastric, great auricular, and small occipital.

Stylo-hyoid : to muscle.

Digastric : given off with former to supply posterior belly of digastric, communicates with glosso-pharyngeal.

Branches on the Face : —

Divides near ramus of inferior maxilla into temporo-facial and cervico-facial.

The TEMPORO-FACIAL crosses over external carotid and temporo-maxillary vein, communicating with auriculo-tem- poral and supplying pinna.

Branches of the Temporo-facial : —

Temporal : supply attrahens aurem, joining temporal of superior maxillary and auriculo-temporal of inferior maxil- lary ; anterior branches supply orbicularis palpebrarum and

NERVES 153

anterior belly of occipito-frontalis, joining lachrymal and supra-orbital nerves.

Malar : to supply eyelid muscles, and join supra-orbital.

Infra-orbital : superficial, to superficial muscles of the face, join infra- trochlear, and nasal (5th). Deep, to elevators of upper lip and angle of mouth, join infra-orbital of superior maxillary.

The CERVICO-FACIAL passes downwards and forwards in parotid, receiving communications from the great auricular nerve.

Branches of the Cervico- facial : —

Buccal : to buccinator and orbicularis oris ; joins buccal of inferior maxillary.

Supra-mandibular : to muscles of lip and chin ; join mental branch of inferior dental.

Infra-mandibular : perforates deep cervical fascia be- neath lower jaw, to join superficial cervical and supply platysma.

The STH or AUDITORY NERVE. Origin — Superficial : Mesial Root : between pons and restiform body. Lateral Root : floor of the 4th ventricle, by the striae acusticae. Deep — both roots: auditory nuclei in floor of 4th ventricle.

Course. — Passes round restiform body to posterior border of crus cerebelli with facial ; it then enters the internal auditory meatus with, the facial nerve, the latter lying in a groove on its upper surface, and divides at the bottom into coJilear and vestibular branches.

Distribution. — Cochlear, supplies cochlea, saccule and posterior semicircular canal ; vestibular, to utricle and superior and external semicircular canals (vide Ear, p. 236).

The QTH or GLOSSO-PHARYNGHAL NERVE. Origin — Super- ficial: from the upper part of the medulla, in the groove between the olive and restiform body. Deep : floor of 4th ventricle.

Course. — Passes outwards over the flocculus to the jugular foramen. Leaves the skull with the pneumogastric and spinal accessory, but in a separate tube of dura mater and in front and external to them, being contained in a canal in the petrous part of the temporal bone. It presents near point of exit two ganglionic enlargements — the jugular and petrous. Issuing from the skull, the nerve passes downwards and out- wards between the internal carotid artery and jugular vein, and then forwards over the internal carotid artery, down- wards behind the muscles attached to the styloid process, to reach the lower border of the stylo-pharyngeus. Thence it

154 THE POCKET ANATOMY

is inclined inwards on the middle constrictor beneath the hyo-glossus to the tongue, pharynx, and tonsil.

The jugular ganglion : the smaller of the two is situated at the upper part of the groove in the temporal bone through which the nerve passes. It involves only the outer side of the trunk of the nerve.

The petrous ganglion is placed in a depression on the in- ferior border of the petrous bone.

Branches : —

Connecting, from petrous ganglion :

(a) To superior cervical ganglion of sympathetic.

(b\ To auricular of pneumogastric.

(c) To ganglion of root of the pneumogastric.

Tympanic (Jacobson's nerve): arising from the petrous ganglion, enters a minute canal in the bone between jugular foramen and carotid canal to reach the inner wall of the tympanum ; runs in a groove over the promontory, giving off several branches, and, after communicating with the facial, is continued forwards as the small superficial petrosal nerve (vide p. 148). This nerve pierces the petrous portion of the temporal to reach the middle fossa just external to the hiatus Fallopii, and, passing through the petro-sphenoidal suture, ends in the otic ganglion. It divides into six branches, which form the tympanic plexus on the promontory.

Three branches of communication, to the carotid plexus and small deep petrosal nerve, to the great superficial petrosal nerve, and to the otic ganglion respectively.

Three branches of distribution, to thefenestraovalis, fenestra rotunda, and mucous membrane of the Eustachian tube respectively.

Pharyngeal (3 or 4) : cross the internal carotid and join opposite the middle constrictor with pharyngeal of pneumo- gastric and sympathetic, to form pharyngeal plexus, supply- ing the mucous membrane of the pharynx.

Communicating with digastric branch of facial.

Muscular : to stylo-pharyngeus and mucous membrane of upper part of pharynx.

Tonsillitic : to the tonsil forming plexus, the circulus ton- sillaris, and thence to fauces and soft palate.

Lingual (2) : one branch distributed to the base supplying the circumvallate papillae, the other to the posterior § of side of the tongue.

Special functions. — Nerve of sensation to the mucous mem- brane of pharynx, fauces and tonsil ; of motion to stylo- pharyngeus muscle ; and of taste of the tongue.

NERVES 155

The IOTH NERVE — the PNEUMOGASTRIC or VAGUS. Origin — Superficial ; sulcus, between restiform and olivary bodies. Deep : Trigonum vagi on floor of 4th ventricle.

Course. — Passes from origin over the flocculus to jugular foramen, through which it passes in same sheath with spinal accessory and behind the glosso-pharyngeal ; in the foramen it presents the ganglion of the root. Upon leaving the fora- men, it is connected with the accessory part of the spinal accessory, and forms an enlargement, the ganglion of the trunk. The accessory part of the spinal accessory nerve passes over the ganglion, some fibres joining the trunk of the nerve, but the principal portions are continued into the pharyngeal and superior laryngeal branches. Thence the nerve passes down in the carotid sheath, behind and between the artery and vein, to the root of the neck, where its course on each side of the body becomes different.

The right nerve passes between ist part of subclavian artery and subclavian vein, and down by side of trachea and behind right innominate vein to posterior part of the root of the right lung, forming the posterior pulmonary plexus ; thence proceed two cords, which run down on the oesophagus, communicate with nerve of opposite side (cesophageal plexus), join belowinto one trunk, which lies behind oesophagus, and passing through cesophageal orifice in diaphragm is distributed to the posterior surface of the stomach, joining solar and splenic plexuses.

The left nerve passes down between the left subclavian and carotid arteries, and behind the left innominate vein, where the left phrenic crosses it ; thence in front of the arch of aorta to posterior surface of root of left lung, forming the posterior pulmonary plexus; then along the anterior surface of oesophagus through diaphragm, to be distributed on the anterior surface of stomach, and join left hepatic plexus.

Connecting branches : —

The ganglion of the root is connected to the spinal accessory, petrous ganglion of the glosso-pharyngeal and sympathetic nerves.

The ganglion of the trunk is connected with the hypo- glossal, sympathetic, and loop between ist and 2nd cervical nerves.

Branches : —

Recurrent : from the upper ganglion, passes backwards to the dura mater of the posterior fossa.

Auricular (Arnold's) : from the ganglion of the root, com- municates with the petrous ganglion of the glosso-pharyngeal, and enters a foramen between the root of the styloid process

156 THE POCKET ANATOMY

and jugular fossa. It passes through the temporal bone com- municating with the facial, and emerges by the auricular fissure just behind the external auditory meatus. Finally it divides into two branches, to supply the back of the pinna, which inosculate with the posterior auricular of the facial.

Pharyngeal : principally formed by fibres from the accessory of spinal accessory, passes superficial to internal carotid artery to upper part of middle constrictor, where it joins branches from glosso-pharyngeal, superior laryngeal, and sympathetic to form the pharyngeal plexus.

Superior laryngeal : from the ganglion of the trunk, passes down behind internal carotid artery, where it divides into external laryngeal nerve, which communicates with pharyngeal plexus and upper cardiac of sympathetic, supplies the crico- thyroid and inferior constrictor muscle and internal laryngeal nerve, which passing through thyro-hyoid membrane, is dis- tributed to the mucous membrane of the larynx, and com- municates with a branch from the recurrent laryngeal.

Inferior or recurrent laryngeal : the right nerve arises in front of subclavian artery, winds back round it, and passes up behind common carotid and inferior thyroid arteries to right side of trachea. The left nerve arises on front of arch of aorta, round which it winds to the left of the ductus arteriosus and passes up by left side of trachea. Both nerves ascend in a groove between trachea and oesophagus, and enter larynx by passing under lower border of inferior constrictor muscle. The nerve supplies all the muscles of the larynx (except the crico- thyroid), the inferior constrictor, communicates with the internal branch of the superior laryngeal, and gives branches to the cardiac plexus, inferior cervical ganglion of the sympathetic, to the trachea, and to the oesophagus.

Cervical cardiac (2 or 3) : Superior are small ; join cardiac of sympathetic. Inferior, one on either side, arise just above ist rib ; the right one passes by the side of innominate artery and joins deep cardiac plexus ; the left one descends in front of the arch of the aorta, and joins superficial cardiac plexus.

Thoracic cardiac : right ones from the trunk of the nerve, end in deep cardiac plexus. Left ones arise from left recurrent laryngeal.

Anterior pulmonary (2 or 3) : to anterior part of root of lung, joining with sympathetic to form the anterior pulmonary plexus.

Posterior pulmonary : numerous, to posterior part of root oi lung, which join branches from 2nd, 3rd, and 4th thoracic

NERVES 157

ganglia of sympathetic, forming the posterior pulmonary plexus.

CEsophageal : to oesophagus, forming a plexus (plexus gulae)

Gastric : the right nerve is distributed to posterior part of stomach, and ends in the solar, splenic and left renal plexuses. The left supplies the anterior surface and ends in the left hepatic plexus.

THE IITH or SPINAL ACCESSORY NERVE. Origin — Super- ficial: the accessory part from the lateral tract below vagus, the spinal part from the side of the cord as low down as the 5th cervical nerve. Deep : anterior horn of grey matter of medulla, and of cord as low as 5th cervical nerve.

Course. — The accessory part passes out of the jugular foramen close to the pneumogastric, and sends one or two branches to the ganglion of the root. It does not blend with the ganglion of the trunk, but joins vagus below. The principal part joins pharyngeal and superior laryngeal branches, but offsets are sent to the cardiac and inferior laryngeal branches. The spinal part enters skull through foramen magnum and passes to jugular foramen ; it is enclosed in the same sheath of dura mater as the vagus. Issuing from the foramen, it passes down- wards between internal carotid artery and internal jugular vein, and then backwards superficial to the internal jugular vein to upper part of sterno-mastoid, which it pierces, at the same time communicating with the branch to the muscle from the cervical plexus. Crossing the occipital part of the posterior triangle, it enters the under surface of the trapezius, where it joins with branches of the 3rd and 4th cervical nerves to form a plexus in the substance of the muscle.

Distribution. — Supplies sterno-mastoid and trapezius muscles.

THE I2TH or HYPOGLOSSAL NERVE. Origin — Superficial: by ten or twelve filaments, from the groove between the olivary body and anterior pyramid. Deep: nucleus beneath trigonum hypoglossi in floor of 4th ventricle.

Course. — The nerve passes in two bundles through anterior 7ondyloid foramen, then downwards and forwards between vagus and spinal accessory, between internal carotid artery and internal jugular vein to the lower border of the digastric muscle ; curving round the occipital artery, it crosses the external carotid and lingual arteries, and passing between the mylo-hyoid and hyo-glossus muscles, ends by dividing into branches on the genio-hyo-glossus.

Branches : —

Communicating. To the ganglion of the trunk of pneumo gastric

158 THE POCKET ANATOMY

To the upper cervical ganglion of the sympathetic.

To the loop between ist and 2nd cervical.

To the lingual branch from the pharyngeal plexus.

To the lingual of the 5th, on the hyo-glossus.

Distributing : —

Descendens cervicis vel hypoglossi : a slender branch, given off as the nerve hooks round occipital artery, passes down over carotid sheath, joining in a loop with branch from 2nd and 3rd cervical (communicans hypoglossi) ; from this loop muscular branches are given to sterno-hyoid, sterno-thyroid, and the two bellies of the omo-hyoid. This branch, and those to thyro-hyoid and genio-hyoid, do not arise from hypoglossal nucleus, but are derived from communication above with ist and 2nd cervical, and merely pass down with hypoglossal.

Thyro-hyoid : passes round great cornu of hyoid bone to supply thyro-hyoid.

Muscular : to stylo-glossus, hyo-glossus, genio-hyoid, genio- hyo-glossus and intrinsic muscles of the tongue.

THE SPINAL NERVES.

There are 31 pairs of spinal nerves, viz. : 8 cervical, 12 dorsal, 5 lumbar, 5 sacral, and i coccygeal. Each nerve arises from the spinal cord by an anterior (motor) and a posterior (sensory) root, the latter having a ganglion developed upon it. These roots join together in the inter vertebral foramen, and upon issuing from it immediately split up again into two parts, the anterior and posterior primary divisions, each containing fibres from the two roots. The anterior primary divisions supply the parts in front of the spine, the posterior primary divisions the parts behind that column.

The posterior primary divisions of the spinal nerves are generally smaller than the anterior, and pass directly back- wards, each quickly dividing into an external and an internal branch, to supply the muscles and integuments behind the spine. To this general rule there are a few exceptions, as posterior primary divisions of the ist cervical, the 4th and 5th sacral, and the coccygeal nerves do not thus subdivide.

THE CERVICAL NERVES. THE POSTERIOR PRIMARY DIVISIONS. The first cervical nerve.— The posterior primary division of the ist cervical or sub-occipital nerve passes backwards

NEfi VES 159

beneath the vertebral artery on the posterior arch of atlas, and, entering the sub-occipital triangle, divides into branches to supply the inferior oblique, which branch communicates with the 2nd cervical nerve, the recti postici major and minor, the superior oblique, and the complexus.

With the exception of the sub-occipital nerve, the posterior primary divisions of the cervical nerves divide into : —

External branches : for the muscles behind the spine.

Internal branches are larger than the external branches, and, with the exception of that from the 2nd cervical nerve (great occipital), pass to spinous processes, supplying the muscles on their way, and become cutaneous. The branch from the 3rd cervical nerve supplies the integument at the base of the occiput (third or least occipital}. The internal branches from the 6th, yth, and 8th end in the muscles.

The great occipital nerve is the internal branch of the posterior primary division of the 2nd nerve. It passes through the complexus and trapezius, and ascends with the occipital artery to the back of the scalp, communicating with the small occipital nerve. It usually has an auricular branch.

THE ANTERIOR PRIMARY DIVISIONS.

The anterior primary divisions of the first four cervical nerves form the cervical plexus, and those of the lower four, with part of that of the ist dorsal nerve, compose the brachial plexus.

The anterior primary divisions of the ist and 2nd cervical nerves differ in form from the rest.

The anterior primary division of the 1st cervical nerve passes outwards in the groove on the outer side of the upper articular process of the atlas, lying behind* the vertebral artery, and giving a branch to the rectus lateralis and recti antici capitis major and minor. It joins the 2nd nerve, and communicates with the sympathetic on the vertebral artery, with the superior cervical ganglion, the pneumogastric, and with the hypoglossal nerves.

The second cervical nerve : the anterior primary division of this nerve winds forward outside the vertebral artery, and divides into an ascending part which joins the ist cervical, and a descending part, which joins the 3rd cervical nerve.

The Cervical Plexus is formed by the union of the anterior primary divisions of the first four cervical nerves after each has communicated with the superior cervical ganglion. It is situated between the sterno-mastoid and the middle scalene muscles. Each nerve except the ist divides into an ascending

160 THE POCKET ANATOMY

branch, which connects it with the nerve above, and a descending branch, which joins it to the nerve below. From the loop between the and and 3rd nerves cutaneous branches are given off to the head and neck, and from the union of the 3rd and 4th nerves superficial branches pass for the shoulder and chest, together with muscular and communicating branches.

SUPERFICIAL ASCENDING BRANCHES : —

Superficial cervical nerve : from loop between 2nd and 3rd nerves, passes forwards over the middle of the sterno-mastoid, perforates the cervical fascia, and divides beneath platysma into : —

Ascending Branch : accompanies external jugular vein, com- municates with the facial, and becomes cutaneous, supplies front of upper half of neck.

Descending : supplies integument as low as sternum.

Great auricular: from and and 3rd. Winds round margin of sterno-mastoid to reach parotid gland. Gives off: —

Facial : over parotid to integument of face.

Auricular : to back part of pinna; communicates with pos- terior auricular.

Mastoid : supplying skin over mastoid process, joining with posterior auricular of facial and small occipital.

Small occipital: from and, ascends along posterior border of sterno-mastoid to scalp, lying between ear and occipital irtery ; supplies integument.

Branch : —

Auricular : supplies integument of cranial surface of auricle.

SUPERFICIAL DESCENDING BRANCH : from 3rd and 4th.

Branches : —

Supra-sternal : to integument as far as middle line.

Supra-clavicular : to integument over pectoral muscle, often pierces clavicle.

Supra-acromial : to integument of shoulder.

DEEP BRANCHES (Internal) : —

Communicating : from loop between ist and and, joins sympathetic, hypoglossal, and pneumogastric nerves.

Communicans hypoglossi : from and and 3rd, form a loop with descendens hypoglossi in front of carotid vessels.

Muscular : to prevertebral muscles and through com- munications with hypoglossal to genio- and thyro-hyoid.

Phrenic : from 3rd and 4th, and a branch from the 5th ; lies in front of scalenus anticus, descends inwards on it in front of subclavian artery to enter the chest, having crossed the internal mammary artery at origin, behind the subclavian vein. In the thorax it descends in front of the root of the

NERVES 161

lung, being between the pericardium and the mediastinal pleura, to the diaphragm, which it perforates, and is dis- tributed on its abdominal surface. The right nerve lies to right of right innominate vein and superior vena cava. The left nerve in the neck is crossed by the thoracic duct, and below crosses the arch of the aorta and left pneumogastric, and is longer than the right. Filaments from each supply the pericardium and pleura.

DEEP BRANCHES (External) : —

Communicating : to spinal accessory in sterno-mastoid and trapezius muscles.

Muscular : to sterno-mastoid from the 2nd, levator anguli scapulae from the 3rd and 4th, scalenus medius from the 3rd and 4th, and trapezius from the 3rd and 4th.

NERVES OF THE UPPER EXTREMITY.

The BRACHIAL PLEXUS is formed by the union and subse- quent division of the anterior primary divisions of the lower four cervical and part of anterior division of the ist dorsal nerves. The 5th and 6th cervical communicate with the middle, and yth and 8th with inferior cervical ganglia. The following is the usual method of union and redivision : —

The 5th and 6th cervical join together at outer border of the scalenus anticus to form an upper trunk.

The yth cervical forms a middle trunk.

The 8th cervical and the ist dorsal form a lower trunk.

Each of these trunks then subdivides into an anterior and a posterior branch.

The anterior branches from the upper and middle trunks form the upper or outer cord of the plexus.

The anterior branch of the lower trunk forms the lower or inner cord of the plexus.

The posterior branches of all the trunks unite to form the posterior or middle cord.

The subjoined scheme will make this arrangement clear : —

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The plexus lies between scalenus anticus and medius, and divides into branches for the upper limb below tlu pectoralis minor.

ii

162 THE POCKET ANATOMY

Branches above the Clavicle : —

Muscular : to the longus colli and scaleni.

Nerve to the rhomboidei, from the 5th cervical, passes through scalenus medius to the base of the scapula, then under levator anguli scapulae, supplying it, and ending on the anterior surface of the rhomboid muscles.

Nerve to the subclavius, from the trunk formed by the 5th and 6th cervical, passes downwards in front of the 3rd part of the subclavian artery to the deep surface of the subclavius, often communicates with phrenic.

Communicating : from the 5th to join the phrenic on the scalenus anticus.

Posterior thoracic, or external respiratory nerve of Bell : from 5th, 6th and yth, pierces scalenus medius and then descends behind the plexus and ist part of axillary artery nearly to the lower border of the serratus magnus, which it supplies.

Supra-scapular: from the union of the 5th and 6th cervical, passes beneath trapezius to upper border of scapula, enters supra-spinous fossa through supra-scapular notch, gives off two branches to the supra-spinatus, and an articular one to the shoulder-joint ; thence it passes to the infra-spinous fossa, and ends in the infra-spinatus.

Branches below the Clavicle : —

The several nerves are given off as follows : —

Outer Cord. Inner Cord. Posterior Cord.

External anterior thoracic. Internal anterior thoracic. Subscapular.

Musculo-cutaneous. Lesser internal cutaneous. Circumflex.

Outer head of median. Internal cutaneous. Musculo-spiral.

Ulnar.

Inner head of median.

External anterior thoracic (outer cord) : crosses over axillary artery to under surface of the pectoralis major, in which it communicates with internal anterior thoracic.

Internal anterior thoracic (inner cord) : passes between axillary artery and vein to the two pectoral muscles.

Subscapular : three (posterior cord).

Upper : the smallest, perforates upper part of subscapularis.

Lower : ends in the teres major, having previously given a filament to the subscapularis. '

Middle or long : runs along lower border of subscapularis with the subscapular vessels to supply the latissimus dorsi.

Circumflex (posterior cord) : passes backwards with pos- terior circumflex vessels at the lower border of the sub- scapularis, through quadrilateral space formed by teres major,

NERVES 163

scapula, long head of the triceps and humerus, and, having given an articular branch to the shoulder-joint, divides into —

Anterior branch : winds round neck of the humerus, supply- ing deltoid and skin.

Posterior branch : gives a branch to teres minot, which has a gangliform swelling upon it ; also branches to deltoid and integument.

Cutaneous appears at posterior border of deltoid, supplies skin over lower § of muscle.

Internal cutaneous (inner cord) : lies in front of 3rd part of axillary artery, becomes cutaneous about middle of arm, and divides into two branches

Anterior : passes behind median basilic vein, supplies front of inner side of forearm as low as wrist.

Posterior : winds over internal condyle, supplying the back of inner side of forearm to about the middle.

Lesser internal cutaneous (nerve of Wrisberg) (inner cord) : lies to inner side of axillary vein, communicates with the intercosto-humeral, and then descends along inner side of brachial vessels to middle of the arm, where it becomes cutaneous and supplies integument of inner side as far as inner condyle. It communicates with the posterior branch of the larger internal cutaneous.

Musculp-cutaneous (outer cord) : perforates coraco-brachi- alis, passing to outer side of arm between biceps and brachialis anticus, supplying the three named muscles ; fila- ments also are given to the elbow-joint ; becomes cutaneous just above elbow, and, passing behind median cephalic vein, divides into —

Anterior cutaneous branch: passes along radial border of forearm, supplying ball of thumb and joining the radial.

Posterior cutaneous branch : supplies integument of lower 3rd of back of forearm on the radial side ; joins branches of radial and musculo-spiral (external cutaneous branch).

Median : arises by two roots, one from the outer cord, the other from the inner cord of the plexus, which cresses 3rd part of axillary artery to join the outer head. At first the nerve lies to the outer side of the axillary artery, but about the middle of the arm it crosses the brachial artery to reach the 'inner side ; it then passes between the two heads of the pronator radii teres, and is continued straight down the forearm upon the flexor profundus, and beneath the flexor sublimis ; at the wrist it lies between the tendons of the flexor sublimis and flexor carpi radialis. Passing beneath the annular ligament, it becomes somewhat

1 64 THE POCKET ANATOMY

flattened, and divides into two parts to supply the outer 31 fingers.

Branches in the Forearm : —

Articular: to elbow-joint.

Muscular : to pronator radii teres, flexor carpi radialis, palmaris longus, and flexor sublimis digitorum.

Anterior interosseous : is given off just below the elbow-joint. It, passes down external to the anterior interosseous artery on the membrane, between the flexor profundus and flexor longus pollicis, to end in the deep surface of pronator quad- ratus. Supplies flexor longus pollicis, pronator quadratus, and outer half of flexor profundus digitorum.

Palmar cutaneous : pierces fascia just above angular ligament, ends in the integument of the palm, joining the palmar cutaneous of the ulnar nerve.

Terminal branches in the Hand : —

Muscular to thumb : supplies abductor, opponens, and outer head of flexor brevis pollicis.

Digital : five in number, supplying outer 3^ fingers, ist and and supply the thumb, 3rd to radial side of index finger also supplies ist lumbrical; 4th supplies and lumbrical and adjacent side of index and middle fingers ; 5th supplies adjacent sides of ring and middle fingers, and joins a branch of the ulnar, giving sometimes a branch to the 3rd lumbrical.

Ulnar (inner cord) : passes down the inner side of axillary and brachial arteries to middle of arm ; it then runs with inferior profunda artery through internal intermuscular septum to groove between olecranon and internal condyle. Thence it passes through the two heads of the flexor carpi ulnaris and descends under cover of that muscle, along ulnar side of forearm and internal to ulnar artery, as far as the pisiform bone ; it then courses over the annular ligament external to that bone, and divides into superficial and deep palmar branches.

Branches in the Forearm : —

Articular : to elbow and wrist joints.

Muscular : to flexor carpi ulnaris and inner half of flexor profundus digitorum.

Cutaneous : arises near middle of forearm, and divides into: superficial to integument of forearm, and palmar, accompanies ulnar artery to hand, supplying the palm : joins the cutaneous of median.

Dorsal cutaneous : comes off about 3 inches above pisiform bone, winds round ulna beneath flexor carpi ulnaris, supplies inner side of little finger, and adjacent sides of ring and little fingers on the dorsal aspect.

NER VES 165

Palmar branches • —

Superficial : supplies palmaris brevis, ends in two digital branches for inner i£ fingers the outer one communicating with the median.

Deep : accompanies deep palmar arch ; it supplies the small muscles of the 5th finger, and gives two branches to each interosseous space, one for each set of interossei ; branches are also given to the two inner lumbrical muscles. In the space between the thumb and index finger the nerve ends by supplying the adductor obliquus, adductor transversus, and inner head of the flexor brevis pollicis.

Musculo-spiral (posterior cord) : winds round between outer and inner heads of triceps in the musculo-spiral groove with superior profuncla artery to the outer side of arm. Piercing the external intermuscular septum, it passes to the external condyle between the supinator longus and brachialis anticus, where it divides into radial and posterior interosseous nerves.

Branches in the Arm : —

Muscular : to the three heads of the triceps, to the anconeus, supinator longus, extensor carpi radialis longior, and brachialis anticus.

Cutaneous : Internal, comes off near axilla, supplies integu- ment on back of arm to near olecranon. External (2), upper one perforates outer head of triceps, accompanies cephalic vein to elbow, supplying the integument of the lower half of arm in front. Lower one supplies integument of lower part of arm, and back part of radial side of forearm as far as the wrist.

Terminal branches : —

Radial : passes down by outer side of radial artery, under cover of the supinator longus, till within 3 inches of the lower end of the radius, where the nerve passes backwards beneath the tendon of the supinator longus, and, becoming cutaneous by piercing the fascia on outer side of forearm, divides into two branches : —

External : supplies ball and outer border of thumb, joining with the external cutaneous nerve.

Internal : joins a branch of the external cutaneous and dorsal of ulnar. It gives off four dorsal digital nerves, thus : ist to inner side of thumb, 2nd to outer side of index, 3rd to adjacent sides of index and middle, 4th to adjacent sides of middle and ring fingers. It thus corresponds in its distribu- tion with the median nerve.

Posterior interosseous : reaches the back of the forearm by piercing the supinator brevis ; there it passes between the superficial and deep layers of muscles to about middle of

1 66 THE POCKET ANATOMY

forearm, where it passes deep to extensor longus pollicis to reach the interosseous membrane, on which it lies, as far as the wrist ; it there ends in a gangliform enlargement, from which there are given off filaments to the ligaments, etc. Supplies supinator brevis, extensores carpi radialis brevior, communis digitorum, minimi digiti, carpi ulnaris, ossis meta- carpi pollicis, longus and brevis pollicis, and indicis.

NERVES OF THE TRUNK.

DORSAL : twelve in number. The ist comes out between the ist and and dorsal vertebrae, and the greater part joins the brachial plexus. The last nerve emerges from between the i ath dorsal and ist lumbar vertebrae. Each nerve at its exit from the intervertebral foramen divides into an anterior and posterior primary division. The ist and I2th nerves, however, require a separate description.

The POSTERIOR* PRIMARY DIVISIONS, or dorsal branches, pass backwards between the transverse processes and divide into external and internal branches, which emerge on either side of the middle division of the erector spinse (longissimus dorsi), and supply the muscles of the back. Cutaneous branches are derived from each of these sets, the six upper ones coming from the internal branches and the six lower ones from the external branches.

The ANTERIOR PRIMARY DIVISIONS, or intercostal nerves, are twelve in number on each side ; each communicates with the corresponding ganglion of the sympathetic chain.

The UPPER six pass forwards in the intercostal spaces below the vessels, lying at first between the pleura and external intercostal muscle, then between the external and internal intercostal muscles ; after giving off the lateral cutaneous branches, they lie in the internal intercostal muscle, and then between that muscle and pleura, extending forwards to the sternum, and crossing the internal mammary artery, to end as the anterior cutaneous nerves of the thorax by perforating internal intercostal and pectoralis major.

Branches : —

Lateral cutaneous : given off midway between head of rib and sternum. .The ist intercostal nerve has generally no lateral cutaneous branch. Each branch, except that from the 2nd nerve, then pierces the external intercostal muscle, and divides into anterior and posterior branches, which supply the muscles, mammary gland, and integument.

The lateral cutaneous branch of the 2nd nerve, or intercosto-

NER VES 167

humeral, has no anterior branch ; the posterior branch crosses the axilla, joins the lesser internal cutaneous nerve, and supplies the integument of the inner side of the arm.

The LOWER six pass like the upper ones to the. front of the intercostal spaces, thence between the internal oblique and transversalis to the sheath of the rectus, which they perforate, and terminate near the middle line as anterior cutaneous branches of the abdominal wall.

Branches : —

Lateral cutaneous: supply the integument of the abdomen, having anterior and posterior branches.

PECULIAR DORSAL NERVES : The ist nerve : its anterior primary division is mostly consumed in the brachial plexus, but a small branch is given off to the ist intercostal space, which has no lateral cutaneous branch. The i2th nerve does not lie in an intercostal space, but below the I2th rib in front of the quadratus lumborum ; it then pierces the posterior aponeurosis of the transversalis, passing forwards between transversalis and internal oblique to end by perforating rectus ; is remarkable for the large size of its lateral cutaneous branch, which does not divide, but, piercing internal and external obliques, passes over iliac crest and supplies skin over gluteal region as far down as great trochanter.

LUMBAR : five on each side. The ANTERIOR PRIMARY DIVI- SIONS increase in size from above downwards, and near their origin communicate with the sympathetic ganglia, the upper four forming the lumbar plexus ; that of the 5th joins with the ist sacral to form the lumbo-sacral cord. The POSTERIOR PRIMARY DIVISIONS pass backwards between the transverse processes and divide into internal and external branches. These are seen to be separated by the longissimus dorsi. The internal branches end in the muscles, and all the external gjve muscular branches; the upper three also give cutaneous branches to gluteal region.

NERVES OF THE LOWER EXTREMITY.

LUMBAR PLEXUS : formed in the psoas by the communica- tions of the anterior primary divisions o£ the four upper lumbar nerves in the following manner : —

The ist gives off the ilio-hypogastric, the ilio-inguinal, a branch to the genito-crural, and a communicating branch to the 1 2th dorsal and 2nd lumbar.

The 2nd gives off branches to the genito-crural, and external

168 THE POCKET ANATOMY

cutaneous, and a communicating branch to the 3rd, which also forms part of the anterior crural and obturator.

The 3rd gives off part of the external cutaneous, of the anterior crural, and of the obturator.

The 4th gives off a branch to the anterior crural, one to the obturator, and a communicating one to the 5th.

Muscular branches are also supplied to the psoas and quad- ratus lumborum.

BRANCHES OF THE LUMBAR PLEXUS.

Ilio-hypogastric : from ist lumbar, appears at upper part of outer border ot psoas, crosses quadratus lumborum to iliac crest, and, piercing the trans versalis, divides into: —

Iliac branch: pierces two oblique muscles, crosses iliac crest behind lateral cutaneous of last dorsal to integument of buttock.

Hyfiogastric branch : pierces internal oblique and then ex- ternal oblique aponeurosis above abdominal ring to integument of hypogastric region.

Ilio-inguinal : from ist lumbar ; passes over quadratus lumborum and iliacus to iliac crest, pierces the transversalis and internal oblique ; it then accompanies the cord through canal and external ring, and is distributed to the integument of the groin and the scrotum.

Genito-crural : from 2nd lumbar, with a branch from ist. Passes on the psoas to Poupart's ligament to divide into : —

Genital branch : crosses external iliac, enters inguinal canal through internal abdominal ring, accompanies spermatic cord, and supplies the cremaster muscle. In the female it accom- panies the round ligament of the uterus.

Cmral branch : passes beneath Poupart's ligament, perforates fascia on outer side of femoral artery, communicates with middle cutaneous nerve, supplies integument of upper and front of thigh.

External cutaneous : from loop between 2nd and 3rd lumbar ; perforates middle of outer border of psoas, and enters thigh just below anterior superior iliac spine, where it divides into : —

Anterior branch: contained at first in a tube of the fascia lata ; supplies outer part of anterior surface of thigh.

Posterior branch : supplies outer surface of thigh to the middle.

Obturator : from 2nd, 3rd, and 4th lumbar ; passes from inner border of psoas, near brim of pelvis and above obturator artery, but below external iliac, to canal in upper part of thyroid foramen. In this canal it divides into : —

NERVES 169

Anterior or superficial part: descends in front of adductor brevis, behind pectineus and adductor longus ; it supplies the hip-joint, gracilis, adductor longus, adductor brevis, femoral artery, and a branch to plexus near sartorius ; rarely the pectineus ; communicates with accessory obturator when this is present.

Posterior or deep part: passes through obturator externus and behind adductor brevis ; it supplies a large branch to adductor magnus, and gives branches also to obturator ex- ternus, adductor brevis when this latter is not supplied by the anterior branch, and a branch along popliteal artery to knee-joint.

Accessory obturator : from 3rd and 4th lumbar or from obturator trunk ; when present it passes down on inner side of psoas, over horizontal ramus of pubes, under pectineus, and supplies pectineus and hip-joint ; communicates with the anterior branch of the obturator.

Anterior crural : from 3rd and 4th, and partly from the 2nd lumbar ; emerges from lower part of outer border of psoas, and descends between that muscle and the iliacus, lying on the outer side of the iliac vessels. It supplies the iliacus and femoral artery whilst in the pelvis, and on emerging from it beneath Poupart's ligament, it divides into : —

Anterior or superficial portion : which gives off : —

Middle cutaneous : pierces fascia lata 3 inches below Poupart's ligament, dividing into two branches to supply the integument of the front of the thigh as far as the knee. Communicates with crural of genito-crural and internal cutaneous, and gives a branch to the sartorius.

Internal cutaneous : passes obliquely across to inner side of femoral artery, and divides into: Anterior branch: pierces fascia lata in lower J of thigh ; supplies integument of the lower £ of inner side of thigh ; communicates near the knee with -long saphenous. Posterior branch : passes down posterior border of sartorius to knee, giving branches to plexus near that muscle, and finally is distributed to integu- ment of the leg; communicates in the thigh with the obturator and the internal saphenous nerves, forming in Hunter's canal a plexiform interlacement, the subsartorial plexus.

Nerve to pectineus : generally two, which pass inwards under femoral vessels to muscle.

Nerves to sartorius : given off with middle cutaneous.

Plexus patella : the patellar plexus is formed by communica- tions between the anterior branch of the internal cutaneous, branches of the middle and external cutaneous nerves, together

i yo THE POCKET ANATOMY

with the patellar branch of the internal or long saphenous nerve.

Deep or posterior part : which gives off : —

Internal or long saphenous : accompanies, lying on outer side of, femoral vessels as far as Hunter's canal, where it crosses, artery, and leaves it at opening in adductor magnus by passing inwards beneath sartorius. Here it. becomes subcutaneous, and is continued with the internal saphenous vein along inner side of leg, behind inner border of tibia, and, passing in front of inner ankle, is distributed on inner side of foot as far as ball of great toe. In its course it gives off a branch to plexus under sartorius formed by obturator and internal cutaneous nerves, to patellar plexus, and below the knee to the integu- ment on the anterior and inner surfaces of the leg.

Muscular. — To the rectus, which gives branch to hip-joint.

To the vastus externus, which gives an articular branch to the knee-joint, and accompanies descending branch of the external circumflex artery.

To the vastus internus, which gives off an articular branch to the knee-joint, and accompanies the deep branch of the anastomotica magna artery.

To crureus, two or three, the internal one supplying sub- crureus and knee-joint.

SACRAL NERVES, five in number. The roots of origin form the cauda equina, and in this region t.he posterior root ganglia are placed inside the spinal canal, though outside the dura mater. Each nerve divides into anterior and posterior primary branches.

The posterior primary branches of the upper four emerge from the posterior sacral foramina, the fifth at the lower end of the spinal canal ; the upper three nerves divide into internal and external branches, the former supplying the multifidus spinae, the latter the integument over sacrum, coccyx, and posterior gluteal region ; the two lower nerves do not divide, and supply filaments to integument over coccyx, the 5th com- municating with the coccygeal.

COCCYGEAL NERVE : this nerve divides into an anterior branch, which pierces sacro-sciatic ligament and coccygeus, supplies integument over coccyx, and communicates with the 5th sacral, forming part of ano-coccygeal plexus ; and a posterior, to supply coccygeal integument.

The ANTERIOR PRIMARY BRANCHES decrease in size from above downwards. The upper four issue from the anterior sacral foramina, the 5th emerging between sacrum and coccyx. Each nerve communicates with the sympathetic. The first

NERVES 171

three and part of the 4th nerves enter the sacral plexus, whilst the lower part of the 4th, the 5th, and the coccygeal nerve form a small plexus, ano-coccygeal, which lies on the pelvic surface of the coccygeus.

The ano-coccygeal plexus : formed as described above. Branches : — Muscular to : — Coccygeus. Levator ani. Sphincter ani externus (usually called the perinea)

branch of the 4th sacral). Visceral. Vesical. Rectal.

Vaginal (in female).

Cutaneous : perforating cutaneous of 4th sacral to integu- ment over coccyx.

The SACRAL PLEXUS is formed by the lumbo-sacral cord (p. 167), anterior primary branches of the upper three and part of that of the 4th sacral nerves. Lies on anterior surface of pyriformis, behind the sciatic and internal pudic arteries. Branches : — Muscular: To pyriformis, from ist and and.

To obturator internus and gemellus superior, from 5th lumbar, ist and 2nd sacral, emerges from pelvis through great sacro-sciatic foramen, winds over ischial spine outside the internal pudic artery, passes in through small sacro-sciatic foramen to inner surface of muscle, having first supplied superior gemellus.

To quadratus femoris and gemellus inferior, given off from lumbo-sacral cord and ist sacral, passes anterior to gemelli and obturator internus tendon to anterior surface of quadratus, giving on its way a branch to gemellus inferior, and an articular branch to the hip-joint.

Superior gluteal : from lumbo-sacral cord and ist sacral, passes out of great sacro-sciatic foramen, above the pyriformis, with the gluteal vessels ; divides into a superior branch, which passes between the two smaller glutei, supplying the medius, and an inferior branch, supplying the gluteus minimus and the tensor fasciae femoris.

Pudic : comes off from the 2nd, 3rd, and 4th nerves, passes out of great sacro-sciatic notch between pyriformis and coccygeus internal to great sciatic nerve, winds over ischial

172 THE POCKET ANATOMY

spine internal to pudic artery, and re-enters pelvis through the small notch lying on inner side of internal pudic artery ; it then enters, with accompanying vessels, a sheath of the obturator fascia in the outer wall of the ischio-rectal fossa and divides into its three branches.

Branches : —

Inferior h&morrhoidal : crosses ischio-rectal fossa to supply external sphincter, skin of anus ; communicates with inferior pudendal of small sciatic and superficial perineal nerves.

Perineal : largest terminal branch, accompanies perineal artery, and divides into :

Cutaneous or superficial perineal, two in number : the internal passes with superficial perineal artery either under or over the transversus perinaei to supply the scrotum ; the external gives a branch to the anus, and, piercing the deep layer of the superficial fascia, supplies the scrotum, joining the inferior pudendal.

Muscular branches supply transversus perinaei, erector penis, ejaculator urinas, compressor urethras, sphincter and levator ani.

Nerve to bulb : pierces ejaculator urinaa and supplies bulb.

Dorsal nerve of the penis : accompanies internal pudic artery between the layers of the triangular ligament lying on the outer side of the artery, pierces the anterior layer of the liga- ment, and the suspensory ligament to reach dorsum of penis, along which it runs as far as the glans, gives off many branches to supply the organ, and joins branches of the sympathetic. In the female this nerve is distributed to the clitoris.

Inferior gluteal : from the lumbo-sacral cord, ist and 2nd sacral nerves ; passes out of pelvis below the pyriformis, at the lower border of which it turns backwards, and, dividing into numerous branches, enters deep surface of gluteus maximus. Communicates near origin with the small sciatic.

Small sciatic : a cutaneous nerve to lower part of buttock and back of thigh ; it comes off from 2nd and 3rd sacral nerves. It passes below the pyriformis with the sciatic artery, and runs down the back of the thigh beneath the gluteus maximus, and below this beneath the fascia lata, which it pierces in the popliteal space.

Branches : —

Internal cutaneous ; to integument of upper and inner side of thigh : one larger one, the inferior pitdendal, turnj inwards over hamstrings, supplies scrotum, and joins the external superficial perineal nerve.

NERVES 173

External cutaneous : winds round ghueus maximus, supplies the integument over lower part of buttock.

Terminal: to integument of thigh, popliteal region, and calf of leg.

GREAT SCIATIC : the largest nerve in the body, and is the main continuation of the sacral plexus, lies in pelvis on pyri- formis ; it is derived from the lumbo-sacral cord, the ist, 2nd, and 3rd sacral nerves. It passes out of pelvis below the pyrifoimis, and between the tuber ischii and great trochanter. resting upon the gemelli, obturator internus, quadratus femoris, and adductor magnus. It is at first external to the biceps, then between its two heads of origin, finally between it and semi-membranosus, and is accompanied by the sciatic artery, which supplies a branch to its substance (comes nervi ischiadici). At a variable distance between the sacral plexus and lower part of the thigh, but generally about the middle of the thigh, the nerve bifurcates into external and internal popliteal.

Branches of the Trunk : —

Muscular : given off under biceps to semi-membranosus, semi-tendinosus, both heads of biceps, and to the inner part of adductor magnus.

INTERNAL POPLITEAL: larger terminal branch, passes along middle of popliteal space to lower border of popliteus, where it gets the name of posterior tibial; it is at first superficial to and outside the artery, but at the lower end of the space, under the gastrocnemius, crosses to the inner side.

Branches : —

Articular (3) : one accompanies each of the upper and lower internal articular arteries, the third the azygos.

Muscular : to the gastrocnemius, one for each head, the outer one supplying also the plantaris. To the soleus and to the Popliteus ; the nerve to the latter turns round lower border of muscle and enters it upon its anterior surface.

Tibial communicating : passes down leg superficially between two heads of the gastrocnemius, pierces the deep fascia about middle of leg, there joining the peroneal communicating from the external popliteal, and is now known as the external or short saphenous nerve ; it then follows the course of the external saphenous vein round outer malleolus, and supplies integu- ment of outejr side of foot and little toe, communicating with the musculo-cutaneous on the dorsum.

POSTERIOR TIBIAL (continuation of internal popliteal): begins at the lower border of the popliteus, and runs with

174 THE POCKET AN ATOM?

the posterior tibial vessels to interval between the external malleolus and heel, where it divides into external and internal plantar. It is at first inside the artery, but afterwards crosses to the outer side. Branches : —

Kluscular : to soleus, tibialis posticus, flexor longus digi- torum, and flexor longus hallucis, the latter accompanying the peroneal artery.

Internal calcanean : pierces internal annular ligament, to supply integument of heel and inner side of sole of foot.

Internal plantar : larger terminal branch of the posterior tibial ; accompanies internal plantar artery along inner side of foot : the larger nerve thus accompanies the smaller artery. Corresponds in distribution to median nerve of hand. It passes between the abductor hallucis and flexor brevis digi- torum to divide opposite the bases of the metatarsal bones into four branches, the outermost of which communicates with the external plantar. Branches : —

Cutaneous : to sole of foot.

Muscular: to abductor hallucis and flexor brevis digi- torum.

Articular : to tarsal and metatarsal articulations. Digital (4) : the ist supplies inner border of ist toe and the flexor brevis hallucis, the 2nd supplies the adjacent sides of the ist and 2nd toes and the ist lumbrical, the 3rd supplies the adjacent sides of the 2nd and 3rd toes, and the 4th supplies the adjacent sides of the 3rd and 4th toes and joins a branch from the external plantar.

External plantar : passes across to outer side of foot with external plantar artery, supplying on its way the abductor minimi digiti and flexor accessorius ; at the outer border of the latter muscle it divides into two branches : —

Superficial : which divides into two digital nerves, one sup- plying the outer side of the little toe, the flexor brevis minimi digiti, and the two interossei of the 4th space ; the other supplies the adjacent sides of the 4th and 5th toes and com- municates with the internal plantar.

Deep or muscular: accompanies deep part of external plantar artery, supplying the adductor obliquus hallucis, adductor transversus Jhallucis, three outer lumbricals and interossei of inner three spaces.

EXTERNAL POPLITEAL OR PERONEAL : passes along the popliteal space under cover of and inside biceps tendon, then over outer head of gastrocnemius to the fibula ;

NERVES 175

i inch below head of that bone it pierces the peroneus longus, and in that muscle divides into anterior tibial and musculo- cutaneous nerves.

Branches : —

Articular (2) : generally given off together, accompany superior and inferior external articular arteries.

Cutaneous : supply integument of back and outer side of leg in upper third.

Peroneal or fibular communicating : arises close to head of fibula and joins the tibial communicating, the two forming the short saphenous nerve.

Anterior tibial : passes to front of interosseous membrane by piercing extensor longus digitorum to reach outer side of anterior tibial artery, with which it descends to the ankle- joint, where it bifurcates into an internal and external branch ; it lies in middle J of leg, in front of artery, and in lowest ^, again, outside it.

Branches : —

Recurrent articular: sends a branch to knee, which accom- panies anterior tibial recurrent artery to joint.

Muscular : to tibialis anticus, extensor longus digitorum, peroneus tertius, and extensor proprius hallucis.

External or tarsal : passes outwards beneath the extensor brevis digitorum and becomes ganglionic, supplies the extensor brevis, and the articulations of the tarsus and metatarsus.

Internal: accompanies dorsalis pedis to ist interosseous space, lying outside it, supplies adjacent sides of ist and 2nd toes, communicating with the musculo-cutaneous.

Musculo-cutaneous : supplies peroneus longus and brevis, and dorsal integument of foot. It passes down between peronei and the long extensor of toes, piercing deep fascia at lower £ of leg.

Branches : —

Muscular : to peroneus longus and peroneus brevis.

Cutaneous : to lower part of leg.

Internal: passes over ankle to inner side of ist toe and adjacent sides of 2nd and 3rd toes, communicates with internal saphenous and anterior tibial nerves.

External : supplies adjoining sides of 3rd, 4th, and 5th toes; communicates with short saphenous.

SYMPATHETIC NERVES The sympathetic system consists of —

1. The great gangliated cords.

2. The prevertebral plexuses, and branches proceeding

from them.

176 THE POCKET ANATOMY

3. Ganglia of union with cranial nerves — viz., ophthal- mic, spheno-palatine, otic, and submaxillary. These have been described with the 5th nerve.

THE GREAT GANGLIATED CORDS,

two in number, extend the whole length of the vertebral column. They consist of ganglia, united by intervening cords, and are placed partly in front and partly by the side of the vertebras. Above they are connected with two plexuses entering the cranium, and below they join together in a loop over the coccyx. The parts of the cords are named accord- ing to the region they occupy — viz., cervical, dorsal, lumbar, and sacral. The cervical portion has three ganglia, whilst in the rest of its extent each cord contains ganglia equal in number to the vertebrae.

Each ganglion is connected with the anterior primary division of the corresponding spinal nerve by an afferent (white) filament, and an efferent (grey) connecting branch. The interganglionic cords are composed of white and grey fibres, the former being continuous with the filaments from the spinal nerves.

The CERVICAL PART of the gangliated cord lies behind the carotid sheath, just in front of the prevertebral muscles, and contains three ganglia.

i. The SUPERIOR CERVICAL GANGLION lies on the rectus capitis anticus major behind carotid sheath, opposite the and and 3rd cervical vertebras.

Branches : —

Connecting : with the anterior primary divisions of ist, 2nd, 3rd, and 4th cervical nerves : with the ganglion of trunk and the ganglion of the root of the pneumogastric, with the hypo- glossal, with the petrous ganglion of the glosso-pharyngeal.

Pharyngeal nerves and plexus : the pharyngeal nerves are given off from the front of the superior cervical ganglion, and pass forwards and downwards. They join with branches from the pneumogastric and glosso-pharyngeal nerves forming the pharyngeal plexus, which lies on the middle constrictor muscle. Branches from the plexus supply the constrictors, levator palati, palato-glossus, palato-pharyngeus, andazygos uvulae muscles : the motor fibres are derived from the bulbar part of spinal accessory, and reach plexus through pharyngeal branch of vagus.

The upper cardiac nerves : the right upper cardiac nerve comes off by two roots from the upper cervical ganglion. It passes downwards behind the carotid sheath, but in front of the inferior thyroid artery and recurrent laryngeal nerve. It

NERVES 177

then goes either behind or in front of the subclavian artery, and, coursing along the innominate, ends in the deep cardiac plexus behind the arch of the aorta. In the middle of the neck it communicates with the external laryngeal, lower down with the upper cardiac branches of the pneumogastric, in the thorax with the recurrent laryngeal, and with other sympa- thetic branches in its whole course.

The left upper cardiac nerve has the same connections in the neck as the right nerve. On entering the thorax, it passes along left common carotid artery, and, crossing the arch of the aorta, joins the superficial cardiac plexus.

Branches to Vessels. — Branches are given to the external carotid artery, which are prolonged to its branches.

Ascending or carotid branch lies behind internal carotid artery, enters carotid canal, and divides into: —

(a) External division : distributed to internal carotid ;

communicates with tympanic branch of glosso- pharyngeal, and forms the carotid plexus.

(b) Internal division : distributed over internal carotid

artery, thus communicating with the external division, and prolonged to form the cavernous plexus.

The carotid plexus lies on the outer side of the internal carotid artery at its 2nd bend.

Branches : —

Connecting : to the 6th nerve and Gasserian ganglion.

The large deep petrosal nerve passes from the plexus through the hiatus Fallopii, to join the large superficial petrosal nerve at the Vidian canal, the junction of the two forming the Vidian nerve.

The small deep petrosal nerve passes backwards in a small canal in the processus cochleariformis, to join the tympanic plexus.

The cavernous plexus lies below and to the inner side of last bend of the internal carotid artery.

Branches : —

Connecting : to the 3rd, 4th, and ophthalmic division of 5th nerve.

Ganghonic : the sympathetic root of the ophthalmic or lenti- cular ganglion passes into the orbit. It is generally joined to the branch of the 3rd nerve supplying the inferior oblique.

Pituitary : to that body.

2. The MIDDLE CERVICAL GANGLION generally lies on the inferior thyroid artery, opposite the 6th cervical vertebra.

Branches : —

Connecting : to the 5th and 6th cervical nerves.

Thyroid: to the thyroid body, communicating with external

12

T7* THE POCKET ANATOMY

and recurrent laryngeal nerves, and with the upper cardiac nerve from the superior ganglion.

Middle or great cardiac nerve : on the right side passes in front or behind subclavian artery to the front of the trachea, and joins the deep cardiac plexus. Communicates in the neck with the upper cardiac and recurrent laryngeal nerves. On the left side it lies between the left carotid and left subclavian arteries, and joins the deep cardiac plexus.

3. The LOWER CERVICAL GANGLION lies between the transverse process of the yth cervical and the neck of the ist rib, behind the vertebral artery, internal to the superior intercostal artery. Branches : —

Connecting : to the 7th and 8th cervical nerves. Lower cardiac nerve : passes behind the subclavian artery, joins recurrent laryngeal, and enters the deep cardiac plexus. Branches to vessels : branches are given to form a plexus round the vertebral artery.

The THORACIC PART of the gangliated cord lies by the side of the vertebrae in a line corresponding to the heads of the ribs. The ganglia are usually twelve in number, and each com- municates with the corresponding intercostal nerve.

Branches of the upper 6 ganglia are given off to the thoracic aorta, vertebras, ligaments, and from the third and fourth to the posterior pulmonary plexus. Branches from the lower 6 ganglia : —

The great splanchnic nerve : formed by the union of branches from the 6th, yth, 8th, gth, and loth ganglia. It passes inwards over the bodies of the vertebras, perforates the crus of the diaphragm, and ends in the semilunar ganglion.

The small splanchnic nerve comes from the loth and nth ganglia, passes with the great splanchnic nerve, and ends in the solar plexus.

The smallest splanchnic nerve comes from the i2th ganglion. It pierces the crus of the diaphragm, and ends in the renal plexus, and partly in the coeliac plexus.

The LUMBAR PART of the gangliated cord lies nearer the middle line than the thoracic on the bodies of the vertebrae. Each ganglion communicates with the anterior division of a lumbar nerve by branches which pass under fibrous arches of psoas. The ganglia give off branches to the aorta, and other branches to form the hypogastric plexus.

The SACRAL PART of the gangliated cord lies to the inner side of the anterior sacral foramina, and is united with its opposite fellow at the lower end of the sacrum by a cord, in

NERVES 179

the middle of which there is sometimes found a coccygeal ganglion or ganglion impar.

Branches are given from the ganglia to the pelvic plexus, and to the middle sacral plexus.

THE PREVERTEBRAL PLEXUSES OF THE SYMPATHETIC.

The CARDIAC PLEXUS lies against the aorta and pulmonary artery. It is divided into two parts, superficial and deep.

The superficial cardiac plexus lies in concavity of the arch of the aorta on the right of the ductus arteriosus. It is com- posed of the left upper cardiac nerve of the sympathetic, the lower cervical cardiac of the left vagus nerve, and branches from the deep plexus. In the plexus is the small ganglion oj Wrisberg. The plexus gives branches to the anterior pul- monary plexus of the left side, and ends in the right coronary plexus which accompanies the right coronary artery.

The deep cardiac plexus lies between the arch of the aorta and the trachea. It consists of right and left halves united by branches. The right half lies above the right branch of the pulmonary artery; the left half lies on the left of the trachea, close to the ductus arteriosus.

Afferent branches : —

a. All the cardiac branches from the cervical ganglia

of the sympathetic, except the left upper nerve.

b. All the cardiac of pneumogastrics and recurrent laryn-

geals, except the lower cervical cardiac of the left vagus.

Efferent branches from the right side join the superficial cardiac plexus to form the right coronary plexus, and others are distributed to the right auricle.

Efferent branches of the left side mostly end in the left coronary plexus, which accompanies the left coronary artery, and in the superficial cardiac plexus.

The SOLAR PLEXUS is the largest prevertebral plexus. It lies behind the pancreas and inferior vena cava, in front of the aorta and crura of the diaphragm. It surrounds the origin of the coeliac axis, extending laterally to the supra-renal bodies. It receives the large and small splanchnic nerves and part of the right pneumogastric. It contains several ganglia, and branches are given off from it to accompany the bloodvessels to the viscera, and to form secondary plexuses on these arteries.

The semilunar ganglia, one in each half of the solar plexus, lie on the inner side of the supra-renal bodies, the left one

12—2

i8o THE POCKET ANATOMY

lying behind inferior vena cava. The great splanchnic nerve enters its upper end.

The diaphragmatic or phrenic plexus accompanies the arteries to the diaphragm. On the right side near the supra- enal body is the phrenic ganglion, connecting together the phrenic nerves of the spinal and sympathetic systems.

The supra-renal plexus is derived from the solar plexus and the outer part of the semilunar ganglion. It is joined by branches of one of the splanchnic nerves.

The renal plexus is derived from the semilunar ganglion, and partly from the solar and aortic plexuses, and receives the smallest splanchnic nerve. It lies along the renal artery, and contains numerous small ganglia.

The spermatic plexus comes off from the renal and aortic plexuses.

The cceliac plexus is derived from the solar plexus. It surrounds the coeliac axis, and subdivides into : —

The coronary plexus accompanies coronary artery along the smaller curvature of the stomach, communicating with the pneumogastric nerves.

The hepatic plexus accompanies hepatic artery into the sub- stance of the liver. Communicates with the left vagus, and the right supra-renal plexus. Gives off the cystic, pyloric, right gastro-epiploic and pancreatico-duodenal plexuses.

The splenic plexus accompanies splenic artery to the spleen, and is joined by the right pneumogastric. It gives off the left gastro-epiploic and pancreatic plexuses.

The superior mesenteric plexus accompanies superior mesenteric artery.

The aortic plexus lies on the anterior surface of the abdominal aorta. It gives off the inferior mesenteric and part of the spermatic plexuses. It ends in the hypogastric plexus.

The HYPOGASTRIC PLEXUS lies between the two common iliac arteries ; it is formed by the terminations of the aortic plexus, together with branches from the lumbar ganglia. It divides below into two parts, which form the pelvic plexuses.

The PELVIC PLEXUSES : two in number. Each is com- posed of a division of the hypogastric plexus, joined with some branches from the 3rd and 4th sacral nerves and ganglia.

The following plexuses are derived from the pelvic plexuses : —

The hsemorrhoidal plexus to the rectum and anal canal.

The vesical plexus to the bladder, with secondary plexuses in the male to the vas deferens and to the vesiculae seminales.

THE ORGANS OF DIGESTION 181

The prostatic plexus to the prostate gland, giving off the cavernous nerves of the penis.

(The vaginal plexus to the vagina.

The uterine plexus accompanying the uterine artery to the uterus.)

THE ORGANS OF DIGESTION.

THE TEETH.

Temporary teeth : the following is the dental formula for the temporary teeth, with the dates in months of their eruption : —

Mo. Mo. Ca. In. In. In. In. Ca. Mo. Mo. ( Upper ..i i i i i i i i i i = io"\

( Lower . . i i i i i i i i i i = ioj 24 12 18 9 7 7 9 18 12 24 months.

Permanent teeth : subjoined is the dental formula for the permanent teeth, with the date in years of their eruption : —

Wis. Mo. Mo. Bi. Bi. Ca. In. In. In. In. Ca. Bi. Bi. Mo. Mo. Wis. I Upper ixxiiixxiiiiiiii = i61

I Lower ixixiixxiixixii i = 16 ) 18 xa 6 10 9 ii 8 7 7 8 n 9 10 6 12 18 years.

THE TONGUE.

The tongue occupies the floor of the mouth ; its base is connected with the hyoid bone, the epiglottis, the pillars of the soft palate, and with the pharynx ; along its inferior surface the genio-glossus runs from base to tip, connecting it to the lower jaw and hyoid bone.

The mucous membrane on the under surface is smooth, forming in front a median fold, the franum lingua; on the sides it is continuous with the mucous membrane of the mouth. On the dorsum there is a rapht along the middle line, which ends posteriorly in the foramen ccecum. Posteriorly the epiglottis is connected to the tongue by three glosso-epiglottic folds, the middle one being called the fr&num epiglottidis . The anterior two-thirds of the dorsum of the tongue is covered with papillae ; they are of three kinds :

The circumvallate papillae (seven to ten) form a row on each side at the back of the tongue, meeting in the middle line thus, A, in front of the foramen caecum.

The fungiform papilla: found principally at the apex ^nd on the sides.

i82 THE POCKET ANATOMY

The filiform papilla are numerous, and are arranged in rows parallel to the circumvallate, but towards the tip of the tongue their direction becomes more transverse.

Glands : near the circumvallate papillae are found numerous mucous glands, known as the lingual glands.

THE MUSCLES OF THE TONGUE. — The extrinsic muscles of the tongue are the hyo-glossus, genio-hyo-glossus, palato- glossus, and the stylo-glossus. These have been described (vide pp. 29 and 30).

The intrinsic muscles are entirely contained within the sub- stance of the tongue, and are as follows : —

The superior lingualis: one on each side. Longitudinal fibres lying under the mucous membrane. It arises from the fraenum epiglottidis, and from the fascia along the middle line ; the fibres pass obliquely outwards, the anterior fibres being longitudinal, to the side of the tongue.

The inferior lingualis (2) is a bundle of muscular fibres running along the under surface of the tongue from base to tip. It lies between the genio-hyo-glossus and hyo-glossus muscles. It arises from the fascia at the base of the tongue, is joined anteriorly with some fibres of the stylo-glossus, and passes to the apex.

Transverse fibres form a horizontal layer of muscular fibres 'between the superior and inferior linguales. The fibres spring from the septum and pass outwards to the sides of the tongue.

Vertical fibres arise from dorsum, and mingle with trans- verse fibres.

The septum of the tongue is a vertical fibrous partition, extending, in the muscular portion, from the hyoid bone to the apex.

Arteries : lingual, tonsillar of facial.

Nerves : lingual or gustatory to anterior two - thirds ; glosso-pharyngeal to side and posterior third ; hypoglossal to muscles.

THE PALATE.

The palate forms the roof of the mouth, and consists of two parts — the front being the hard palate, and the back the soft palate.

The hard palate consists of the palatal processes of the superior maxillae and palate-bones, together with the mucous membrane and the periosteum covering them . The descending palatine artery and anterior palatine nerve run forwards under cover of alveolus.

THE ORGANS OF DIGESTION 183

The soft palate, consisting of muscles, aponeurosis, vessels, nerves, etc., enclosed between two layers of mucous mem- brane, is attached in front to the posterior margin of the hard palate, the sides blending with the pharynx ; from the middle of the posterior edge the uvula projects, and from the bases of this arch, on each side, there are two folds of mucous membrane enclosing muscular fibres — the pillars, anterior and posterior, between which the tonsil lies. The narrowed passage between the anterior pillars, leading from the mouth to the pharynx, is called the isthmus faucium.

The aponeurosis of the soft palate is attached to the posterior edge of the hard palate, is joined by the tendon of the tensor palati, and becomes lost between the muscles.

Structure of the palate from before backwards :

1. Oral mucous membrane and mucous glands.

2. Palato-glossus.

3. Aponeurosis.

4. Tensor palati.

5. Anterior fibres of palato-pharyngeus.

6. Levator palati.

7. Azygos uvulae in middle line.

8. Posterior fibres of the palato-pharyngeus.

9. Mucous glands and pharyngeal mucous membrane. The tonsils occupy the recesses between the pillars of the

fauces, the anterior pillar being formed by the palato-glossus and the posterior by the palato-pharyngeus. On the outer side of each is the superior constrictor, and internally the buccal mucous membrane. Their arterial supply is large, from the ascending pharyngeal, ascending and descending palatine, tonsiilar, and dorsalis linguae arteries.

THE SALIVARY GLANDS.

The PAROTID GLAND is the largest, and lies between the external auditory meatus and mastoid process behind, and the vertical ramus of the jaw in front. Anteriorly, it overlaps the hinder part of the masseter.

Boundaries : —

Ex- ternally.	Above.	Below.	Anteriorly and Below,	Behind,
Skin.	Zygoma.	Line from angle	Stylo-maxil-	External audi-
Platysma. Cervical		of jaw to mas- toid process.	lary liga- ment.	tory meatus. Mastoid process.
fascia.		Posterior belly of		Sterno-mastoid.
		digastric

[84

THE POCKET ANATOMY

The deep surface is irregular, and lies on the styloid process and its attached muscles, the internal jugular vein, the vagus, spinal accessory and hypoglossal nerves, and is divided into three lobes : —

The glenoid lobe fills up glenoid cavity behind Glaserian fissure.

The pterygoid lobe passes forwards internal to the ramus of the jaw between the external and internal pterygoid muscles.

The carotid lobe surrounds the styloid process, and lies between the external and internal carotid artery.

The socia parotidis is a separate lobe projecting from the anterior surface.

Relations of the Socia Parotidis : —

Above. Below.

Zygoma. Duct.

Cervico-facial divi- sion of facial nerve.

Internally. Masseter. Transverse facial artery.

The duct (Stenson's) is 2 inches long ; comes off from the anterior border and crosses the masseter to pierce the buccinator and buccal mucous membrane. Its opening in the mouth is opposite the 2nd upper molar tooth.

Course of the duct: line from bottom of lobule of ear to middle of upper lip. The transverse facial artery lies above the duct, and the buccal branches of the yth nerve below.

The parotid gland is traversed by the following, of which the arteries lie deep and the nerves most superficial.

Veins. Nerves.

Internal maxillary. Facial. Temporal. Auriculo-temporal.

Temporo-maxillary . Facial of great auri- cular.

Arteries.

External carotid. Posterior auricular. Internal maxillary. Superficial tem- poral. Transverse facial.

Nerve supply of gland : sympathetic and glosso-pharyngeal. The latter branch may be traced as follows : The tympanic (Jacobson) branch gives off small superficial petrosal, which passes through otic ganglion and joins the auriculo-temporal trunk, thus supplying the gland.

THE SUBMAXILLARY GLAND lies under cover of the body oi the lower jaw.

Superficial lobe: separated by stylo - maxillary ligament from parotid, grooved above and behind by facial artery.

THE ORGANS OF DIGESTION 185

Lies upon. Superficial Coverings. Below.

Mylo-hyoid. Platysma. Tendon of

Stylo-hyoid. Deep fascia. digastric.

Hyo-glossus. Facial vein.

Deep lobe : passes with duct between mylo-hyoid and hyo- glossus.

The duct of Wharton : passes with deep lobe of gland beneath mylo-hyoid, resting on the hyo-glossns. At first the lingual nerve lies above the duct and the hypoglossal nerve below, but the duct, crossing over the nerve, passes up- wards and forwards on genio-hyo-glossus to open on the papilla by the side of the fraenum linguae.

Nerves : sympathetic, and chorda tympani through sub- maxillary ganglion.

THE SUBLINGUAL GLAND occupies the sublingual fossa of lower jaw, lying under mucous membrane of floor of mouth, and having its anterior extremity close to the fraenum. Below is the mylo-hyoid, and internally is the genio-hyo-glossus.

Ducts of Rivini (18 to 20) : open separately in the floor of the mouth. One larger one from the posterior part opens into or by the side of Wharton's duct, and is called the duct of Bartholin.

Nerves : sympathetic, and from chorda tympani through submaxillary ganglion.

THE PHARYNX.

The Pharynx is an oval musculo-membranous bag lying behind the nose, mouth, and larynx. It is about 4^ inches long, and extends from the base of the skull to the lower border of the cricoid cartilage in front, and to the lower border of the 5th cervical vertebra behind. It is widest opposite the hyoid bone. Behind, it is separated by a pre- vertebral layer of the deep cervical fascia from the longus colli and rectus capitis anticus muscles of each side. Below, it is continuous with the resophagus.

A ttachments : —

Above : under surface of body of sphenoid, under surface of petrous of temporal.

In front: internal pterygoid plate, pterygo-maxillary liga- me%». lower jaw, base of tongue, cornua of hyoid bone, and styj \ hyoid ligament ; thyroid and cricoid cartilages, corre- sponding to attachments of constrictor muscles.

1 86

THE POCKET ANATOMY

Behind. Longi colli. Recti capitis antici. Upper 5 cervical

vertebrae. Prevertebral fascia.

Below. (Esophagus

Relations :—

Laterally. Styloid process. Stylo-hyoid. ^ ^

Stylo-pharyngeus. jo Internal pterygoid. I & Sterno-thyroid. I £ Sterno-hyoid. J ^ Internal and common >

carotid.

Ascending pharyngeal. Ascending palatine. Tonsillar.

Internal jugular vein. Glosso-phary ngeal . Pneumogastric. Sympathetic. Spinal accessory. Hypoglossal. Superior laryngeal. Thyroid gland.

Muscles : inferior, middle and superior constrictors, stylo- pharyngeus, palato-pharyngeus, salpingo-pharyngeus. (Vide pp. 29 and 30.)

A runes : Ascending pharyngeal ; pterygo-palatine ; ascend- ing and descending palatine ; dorsalis linguae ; tonsillar.

Openings : the posterior nares (2), placed in the upper part of the anterior wall ; Eustachian tubes (2), open one on each side at the upper part; the mouth, situated just below the posterior nares ; the laryngeal and cesophageal openings.

The pharyngeal wall consists of 4 layers : (i) internally a striated squamous epithelium with submucous tissue ; (2) pharyngeal aponeurosis ; (3) muscular ; (4) an indistinct layer of fascia called the bucco-pharyngeal fascia, derived from the deep cervical fascia.

The pharyngeal aponeurosis forms the base of the walls of the pharynx, lying between the mucous membrane, and the muscles. It is thin below, but strong above, where it fills in the space above the upper crescentic margin of the superior constrictor (sinus of Morgagni), over which the Eustachian tube passes. It is attached above to the body of the sphenoid and petrous portion of the temporal, being strengthened in the middle line by a process of fascia attached to the pharyngeal tubercle on the basilar part of the occipital bone. Inferiorly it becomes lost between the muscular and mucous strata.

THE ORGANS OF DIGESTION

187

THE (ESOPHAGUS.

The oesophagus extends from pharynx to stomach, and is 9 inches long. It begins at the lower border of cricoid cartilage opposite the 5th cervical vertebra, and ends opposite the loth dorsal.

Course and relations : —

In the neck : passes downwards and to the left.

In Front. Trachea. Thyroid gland. Left recurrent

1 a r y n g e a 1

nerve.

Behind. Vertebrae. Left longus colli muscle.

Left Sidt. Left inferior thy- roid.

Left carotid. Left subclavian. Thoracic duct.

Right Side. Right carotid. Right recurrent

1 a r y n g e a 1

nerve.

In the chest. — In the superior mediastinum passes down- wards to the right to reach middle line opposite 5th dorsal vertebra.

In the posterior mediastinum : passes forwards and down- wards to the left, with the two pneumogastrics, which form a plexus on its surface ; the left nerve is anterior, and the right is posterior.

Behind.

In Front. Left carotid artery. Longus colli. bifurcation of Vertebra.

trachea. Thoracic duct.

Right pulmonary Venae azygo

artery.

Left bronchus. Left recurrent laryn- vessels.

geal nerve. Aorta (below).

Pericardium and left

auricle. 1 liaphragm.

inores.

Right intercostal Thoracic aorta. Left pleura.

Left Side. Right Side.

Left subclavian Right pleura.

artery. Vena azygos

Left pneumogas- major.

trie nerve. Arch of aorta.

In the abdomen : passes through cesophageal opening in diaphragm opposite the disc between the gth and roth dorsal vertebrse, to end at the cardiac opening of the stomach opposite the loth dorsal vertebra.

THE STOMACH.

Form : conical, with base or fundus to left side ; the upper border is concave, and is called the lesser curvature ; the lower border is convex, and is named the greater curvature. The left extremity is known as the fundus, above and to the right of which is the cardiac orifice, and the right or small end is termed the pyloric extremity.

i88 THE POCKET ANATOMY

Position : occupies left hypochondriac and epigastric regions.

Orifices : cardiac, above, communicating with the oeso- phagus; pyloric, at the right extremity, passing into the duodenum.

Dimensions : 10 to 12 inches long ; 4 to 5 inches in diameter at widest part.

Relations : —

Left or cardiac end : fixed by oesophagus and gastro-phrenic ligament to diaphragm, lying beneath the yth left costal cartilage, i inch from sternum : it is connected with the spleen by the gastro-splenic omentum.

Right or pyloric end .- reaches gall-bladder, touching under part of quadrate lobe of liver ; is very movable, when stomach is empty is in mid-line on line midway between upper border of sternum and upper border of pubis, over ist lumbar vertebra.

Anterior surface, which also looks upwards, is in contact with, from left to right, diaphragm, abdominal parietes (epi- gastric region), under surface of liver.

Posterior surface is separated from diaphragm, aorta, pan- creas, spleen, left kidney, and supra-renal, transverse meso- colon and colon, by lesser sac of peritoneum.

Superior border : attached to liver by small omentum.

Inferior border : gives attachment to great omentum.

ARTERIES. — Coronary and pyloric run along lesser curvature ; right and left gastro-epiploic, along inferior or greater curvature ; vasa brevia, from the splenic to fundus.

NERVES. — Right pneumogastric, to posterior surface; left [neumogastric, to anterior surface ; sympathetic, from the solar plexus to both surfaces.

THE SMALL INTESTINES.

THE DUODENUM.

Length : 8 to 10 inches.

Shape : horse-shoe, with the convexity to the right side, the concavity enclosing the head of the pancreas.

Position : occupies epigastric and umbilical regions.

Has no mesentery, and is only partially invested by peri- toneum.

Divided into three parts.

Relations : —

1st part : 2 inches long ; directed from pylorus upwards, backwards, and to the right, reaching the neck of the gall-

THE SMALL INTESTINES 189

bladder. The ist inch is invested with peritoneum, but the 2nd inch is covered in front only.

In front. Liver, gallbladder.

Behind. Bile - duct, 'vena portae, hepatic artery, gastro- duodenal artery.

Below. Head of pancreas.

2nd part : 3^ inches long ; is vertical ; passes from opposite neck of gall-bladder down to 3rd lumbar vertebra. Ducts of liver and pancreas enter this part. Covered in front by peritoneum.

In front. Transverse colon, liver and gall-bladder, small intestines.

Behind. Right kidney, supra-renal capsule, renal vessels, and inferior vena cava.

Left side. Head of pancreas, common bile - duct, and pancreatic duct.

Right side. Hepatic flexure of colon.

On the inner aspect, 3^ or 4 inches from the pylorus, is the bile papilla, on which is the orifice for both the common bile and pancreatic ducts.

3rd part : about 4^ inches long ; passes from right to left across spine, ascending from 3rd to and lumbar vertebra, ends in jejunum on left side of spinal column ; lies below transverse meso-colon, and is covered in front by peritoneum, except where root of mesentery crosses it.

In front. Superior mesenteric vessels and plexus.

Behind. Aorta, inferior vena cava, crura of diaphragm, left psoas, and left renal vessels.

Above. Pancreas.

ARTERIES. — Pyloric, and superior pancreatico-duodenal of hepatic, inferior pancreatico-duodenal of superior mesenteric.

NERVES, from solar plexus.

THE JEJUNUM AND ILEUM.

The jejunum forms f of the rest of the small intestines, which are 23 feet long ; commencing on the left side of the 2nd lumbar vertebra, it terminates in the ileum ; it is wider, and its coats are thicker, more vascular, and of a deeper colour than the ileum.

The ileum consists of the remaining f of the small intestines, and terminates in the right iliac fossa by opening into the caecum.

The ileum with the jejunum is suspended from the posterior abdominal wall by the mesentery (p. 196). The vessels are derived from the superior mesenteric artery, and the veins drain into the vein of the same name.

i go THE POCKET ANATOMY

The following characteristics will serve to distinguish the three parts of the small intestines :

Duodenum. The largest part. Thickest coats. Brunner's glands. Valvular conniventes. No mesentery.

Jejunum. More vascular than ileum. Valvulae conniventes. Villi, well marked.

Ileum. Villi, small. Valvulae conniventes, not present or only slightly. Peyer's patches.

THE LARGE INTESTINE.

Extent .- from the ileum to the anus. Length : 5 or 6 feet.

Characteristics of Ccecum and, Colon. — Larger size, more fixed than the small intestine ; has appendices epiplo'icse. The longitudinal muscular fibres are arranged in three bands, which, being shorter than the other coats, cause sacculation.

The caecum is a dilated pouch in which the large intestine commences, situated in the right iliac fossa, and completely covered by peritoneum ; at the lower, inner, and back part, and generally attached by a mesentery to the caecum, is the appendix vermiformis, a blind tubular projection, about 3 inches long, and about the size of a large quill.

The ileo-ccscal valve lies on the left side of the caecum ; is formed by the two inner coats of the ileum passing through the wall of the caecum. The upper fold is horizontal, and called the ileo-colic. The lower is vertical, and termed the ileo-caecal. The ridge on either side is called the frcznum.

The COLON is divided into ascending, transverse, descend- ing, iliac and pelvic.

The ascending colon extends from the caecum to the under surface of the liver to the right of the gall-bladder, where it turns to the left, forming the hepatic flexure. It lies in the right lumbar and right hypochondriac regions. The peritoneum covers the anterior and lateral surfaces. Length, 8 inches.

Relations. — In front. The convolutions of the ileum.

Behind. Iliacus, quadratus lumborum, outer side of right kidney.

The transverse colon passes in the umbilical region from right to left, from the gall-bladder to the spleen. It forms an arch, convex anteriorly and below : the transverse arch of the colon. It is entirely surrounded by peritoneum, which is attached posteriorly to the spine, forming the meso-colon. Length, 20 inches.

Relations. — Above. Liver, gall-bladder, large curvature of stomach, lower end of spleen.

Below. Small intestines.

Anteriorly. Anterior layers of great omentum, anterior abdominal wall.

THE LARGE INTESTINE 191

Posteriorly. Right kidney, 2nd part of duodenum, transverse meso-colon, pancreas, and small intestines.

The descending colon passes from the end ot the transverse colon by a bend, the splenic flexure. Between the splenic flexure and the diaphragm, opposite the roth left rib, is a fold of the peritoneum, the costo-colic ligament, which slings up the spleen. The gut then passes downwards to the left iliac crest, ending in the iliac colon. The peritoneum invests its anterior and lateral surfaces. Length, 4 to 6 inches.

Relations.— Behind. Left kidney, quadratus lumborum, and psoas.

In front. Small intestine.

Inner side. Outer border of left kidney.

The iliac colon is continuous with the descending colon at the left iliac crest, and ends at the inner border of the left psoas.

Peritoneum invests its anterior and lateral surfaces ; it has no mesentery.

Relations. — In front. Small intestines; when distended, the anterior abdominal wall. Behind. Left ilio-psoas.

Length. 5 to 6 inches.

The pelvic colon extends from the inner border of the psoas to the level of the 3rd sacral vertebra.

Length. 16 or 17 inches ; very variable. It has an extensive mesentery.

Relations.— Passing over left brim of pelvis, it crosses left external iliac vessels and left ureter, and passes to right margin of pelvis, resting on bladder in male and uterus in female ; above lie coils of small intestine. It then turns back to mid-line on posterior wall of pelvis, and, forming a second bend, descends to end in the rectum.

The rectum : —

Extent. — From the 3rd sacral vertebra to the tip of the coccyx (5 to 6 inches long).

Relations. — It has peritoneum on the upper § of anterior surface only, and no mesentery.

In front. Recto-vesical pouch : triangular area at base of bladder, vesiculaeseminales, vasa deferentia, posterior surface •of prostate (male), posterior wall of vagina (female).

Behind. Sacrum, coccyx, levatores ani.

Laterally. Pararectal fossa, below coccygeus.

The anal canal :—

Extent. — From the tip of the coccyx to anus (i to i£ inches Jong).

Direction. Downwards and backwards.

Relations : —

In front. Membranous part of the urethra, bulb of corpus

192 THE POCKET ANATOMY

spongiosum (male), posterior wall of vagina, the perineum intervening (female).

Laterally and behind. Levatores ani, which, uniting, support it as in a sling. Internal and external sphincters. Ischio- rectal fossa.

THE LIVER.

Situation.— Right and left hypochondriac and epigastric regions.

Average weight. — 50 ounces.

Upper surface. Convex, covered by peritoneum; above is the diaphragm. It is divided into two unequal lobes (right and left) by a fold of peritoneum, called the suspensory or broad ligament. In relation with the diaphragm,

Under surface. Concave, and is in relation with the stomach, pylorus, duodenum, hepatic flexure, right kidney, and right supra-renal body ; is covered with peritoneum, except where gall-bladder is attached, and at the transverse fissure, and at the fissure for ductus venosus, which give attachment to the lesser omentum.

Posterior surface. Is broad and round : connected to dia- phragm over right lobe by the coronary ligament, (between the two layers of which its surface is non-peritoneal. On this surface, opposite the loth and nth dorsal vertebrae, is the Spigelian lobe, which bounds the lesser sac in front. Right supra-renal capsule, inferior vena cava, aorta, oeso- phagus, and lesser peritoneal sac lie behind.

Anterior surface. Triangular, and marked by a notch opposite the attachment of the suspensory ligament. In relation with diaphragm and anterior abdominal wall.

Right surface. Convex and in relation with diaphragm.

The LIGAMENTS are five in number ; four are composed of peritoneum, and are : —

The suspensory, falciform, or broad ligament, sickle-shaped, with the base forward. It is attached above to the diaphragm, extending on to the sheath of rectus as far as the umbilicus, and below from the notch in front, to the posterior edge of the liver. The inferior edge encloses the round ligament.

The lateral ligaments, right and left, extend from the sides of the diaphragm to the posterior border of the liver.

The coronary ligament is continuous with the lateral liga- ments, and attaches the posterior surface of right lobe of the liver to the diaphragm.

The round ligament is the obliterated umbilical vein and ductus venosus contained within the posterior or free edge of the suspensory ligament.

THE LIVER 193

FISSURES : —

The longitudinal fissure is occupied by the round ligament, and divides the organ into right and left lobes ; it is separated into two parts by its union with the transverse fissure.

The anterior part or umbilical fissure contains the remains of the umbilical vein, and lies between the left lobe and the lobus quadratus. The posterior part or fissure of the ductus venosus lies between the left lobe and the lobus Spigelii, and contains the remains of the ductus venosus.

The transverse or portal fissure is placed at right angles to the longitudinal fissure, between the lobus quadratus and the lobus Spigelii, and lodges the hepatic ducts, artery, and portal vein, nerves and lymphatics. The artery lies between the duct in front, and the vein behind.

The fissure for the inferior vena cava is placed obliquely at the posterior margin of the liver, behind the gall-bladder, lying between the right lobe and the lobus Spigelii, and sepa- rated from the transverse fissure by the lobus caudatus. The hepatic veins enter the vena cava at the bottom of this fissure.

LOBES : —

Right and left lobes are separated from each other by the umbilical fissure on the under surface, and posteriorly by th^ fissure of the ductus venosus. The right is the larger, ami contains the transverse fissure and fissure for the inferior vena cava ; is subdivided into the three following lobes : —

Tiie lobus quadratus : bounded by the umbilical and trans- verse fissures and the fossa of the gall-bladder.

The lobus Spigelii is on the posterior surface, and is the projection between fissures for the inferior vena cava and ductus venosus, behind the transverse fissure.

The lobus caudatus connects the preceding lobe with the main mass of the right lobe, and lies behind the transverse fissure.

FOSSA : —

The fossa for the gall-bladder lies on the under surface of the right lobe, parallel to the umbilical fissure, and separates the quadrate lobe from the main mass of the right lobe.

THE GALL-BLADDER AND BILE-DUCTS.

The gall-bladder is a conical bag placed in a fossa on the under surface of the right lobe of the liver. Its upper surface is attached to the liver, and its fundus and posterior surfaces are invested by peritoneum reflected from the adjacent surface of the liver.

Relations. — The body is in relation in front with the liver

13

194 THE POCKET ANATOMY

and behind with the ist part of duodenum, and the hepatic flexure of colon. The fundus is in contact with the parietes opposite the gth right costal cartilage.

The cystic duct passes from the neck of the gall-bladder downwards, backwards, and to the left, to join the hepatic duct at the mouth of the portal fissure.

The hepatic duct, formed by union of ducts from right and left lobes, issues from the liver at the bottom of the transverse fissure. It joins the cystic duct, the two forming the common bile-duct. Its length is i inch, and it lies entirely within the portal fissure.

The ductus communis ckoledoclms or common bile-duct results from the union of the hepatic and cystic ducts. It passes downwards in front of the foramen of Winslow in the layers of the gastro-hepatic omentum, having the vena porta behind, and the hepatic artery on the left. It then descends behind the ist part of the duodenum, and, passing between the pancreas and 2nd part of the duodenum where it lies on the inferior vena cava, it enters the small intestine obliquely, a little below the middle of the descending part of the duo- denum, by an opening on the biliary papilla (p. 189) common to it and the pancreatic duct. Length 3 inches. Vessels of the liver : —

The hepatic artery from the coeliac axis enters the trans- verse fissure and divides into two branches for the right and left lobes. The right branch gives off the cystic branch to the gall-bladder.

The portal vein, having the hepatic artery on the left and in front, and the common bile-duct on the right, ascends between the layers of the gastro-hepatic omentum, in front of the fora- men of Winslow, to the transverse fissure. The vessels, accom- panied by nerves and lymphatics, are surrounded by areolar tissue, the capsule of Glisson, which passes with them into the liver.

The hepatic veins pass out of the liver at the bottom of the fissure of the inferior vena cava, immediately joining that vessel.

THE PANCREAS.

Length : 6 to 8 inches. Consists of a body, enlarged to the right at its head, with which the body is connected by a narrow part or neck, and narrowed to the left, where it ends as the tail.

Position. — Placed in the epigastric and left hypochondriac regions, directed transversely across posterior wall of abdomen.

THE PANCREAS 195

Relations of the body : —

Upper surface. Stomach and small omentum : covered by peritoneum.

Posterior surface. Aorta, crura of diaphragm, splenic vein, left kidney, left supra-renal body and left renal vessels.

Upper border. From right to left ; creliac axis, splenic artery.

Inferior surface. From right to left ; duodeno-jejunal flexure, splenic flexure, and small intestines : covered by peritoneum.

Left end or tail. Touches lower part of internal surface of spleen.

Right end or head. Embraced by three parts of duodenum, from which it is partly separated, behind by common bile- duct, and in front by pancreatico-duodenal arteries. Is covered in front by transverse colon : the superior mesen- teric vessels overlap the left end of the head, lying in a groove on the anterior surface. Behind are inferior vena cava and right renal vessels.

Neck lies on the 1st and 2nd lumbar vertebrae, from which it is separated by the crura of the diaphragm, superior mesen- teric vessels, and portal vein.

Duct (canal of Wirsung) : extends transversely from left to right, opens into 2nd part of the duodenum in common with the ductus communis choledochus.

Arteries: pancreatic of splenic, superior pancreatico-duo- denal of hepatic, and inferior pancreatico-duodenal of superior mesenteric.

Veins : open into splenic and superior mesenteric.

Nerves : from the solar plexus.

THE SPLEEN

situated in the left hypochondrium and epigastrium, is of an oblong, flattened form, the external surface being convex ; on the inner surface is a vertical ridge dividing it into two parts, the posterior of which is applied to the outer surface of the left kidney, whilst the anterior receives the tail of the pancreas, and lies against the fundus of the stomach. Near this ridge is a fissure, the hilum, where the vessels enter. The anterior border is notched, and the inferior or basal sur- face is triangular, and rests on the costo-colic ligament (vide S. 191) and the splenic flexure. It is covered, except at the ilum, by peritoneum, which here passes forwards and inwards in a double line enclosing the vessels, as the gastro-splenic

13—2

ig6 THE POCKET ANATOMY

omentum, to the fundus of the stomach: behind the hilum two layers pass on to the left kidney as lieno-renal ligament.

Relations. — External surface. Diaphragm, which separates it from the gth, ioth, and nth left ribs and pleura.

Internal surface. In front of the hilum. Fundus of stomach . Behind the hilum. Left kidney, left supra-renal body. Below the hilum. Tail of pancreas.

Inferior surface. Costo-colic ligament and splenic flexure.

Arteries: Splenic.

Nerves : Branches from solar plexus of the sympathetic.

THE PERITONEUM.

The peritoneum is the serous membrane of the abdominal cavity. It consists of a parietal layer lining the abdominal and pelvic walls, and a visceral layer reflected more or less over the contained organs. In the male it is a closed sac, but in the female the free extremities of the Fallopian tubes open into the cavity. The continuity of the peritoneum may bt, traced in the following manner.

Commencing at the middle line and passing horizontally, the peritoneum lines the right half of the abdominal wall, as far as the lumbar region, where it entirely surrounds the caecum and vermiform appendix. It only invests the front and sides of the ascending colon, though occasionally the whole circumference of the gut is enclosed, a meso-colon being then formed. The peritoneum then passes inwards, covering the lower part of the anterior surface of the right kidney, the front of the 3rd part of duodenum, and goes downward over the front of the vessels of the small intestines, encloses the small intestines, and is reflected upwards on the posterior surface of the vessels to the spine, thus forming the mesentery. From the spine it may be traced to the left over the lower part of the anterior surface of the left kidney to the descending and iliac colon, and thence on to the abdominal parietes to the middle line. The descending and iliac colon is invested in a similar manner to the ascending.

The peritoneum of the pelvis is continuous with that of the abdominal cavity. It encloses completely the pelvic colon, and forms the pelvic meso-colon. It is applied to the front and sides, and lower down to the front only of the rectum, whence it is reflected in the male on to the base and upper part of the bladder, forming the recto-vesical pouch ; this is bounded on each side by the peritoneum

THE PERITONEUM 197

reflected forwards from the sides of the rectum over the obliterated hypogastric artery and ureter,lformingthe/>osten'or false ligament of the bladder.

From the apex of the bladder the peritoneum passes upwards on to the anterior abdominal wall, enclosing the remains of the urachus and constituting the anterior false ligament of the bladder ; whilst laterally it is reflected from the bladder along the line of the obliterated hypogastric artery to the iliac fossa, forming the lateral false ligaments of that viscus. Where the obliterated hypogastric artery passes between the abdominal wall and the side of the bladder it raises the peritoneum into a fold, which separates two shallow fossae, the internal and external inguinal fosses, which correspond respectively to the internal and external abdominal rings.

In the female the peritoneum is reflected from the sides and front of the rectum to the upper part of the posterior wall of the vagina, and thence over posterior, upper, and anterior surfaces of the uterus to the bladder. Between the uterus and rectum is the recto-vaginal or Douglas's pouch, corresponding to the recto-vesical pouch in the male. The peritoneum passes off from the lateral margins of the uterus to the pelvic wall, forming the broad ligaments, in the upper border of which folds the Fallopian tubes run, the peri- toneum being continuous with their open fimbriated ex- tremities.

In the upper part of the abdomen the peritoneum is attached to the under surface of the diaphragm as far back- wards as the posterior surface of the liver, and the oesophageal opening of the stomach. It is then reflected forwards on the upper surface of the liver, forming the ligaments of that organ ; and passing round the anterior border it is applied to the under surface as far as the transverse fissure, where, meeting a peritoneal layer from the posterior surface (from the smaller sac), the two descend to the stomach to form the small or gastro-hepatic omentum. Tracing it to the right from the longitudinal fissure, it invests the gall-bladder, under surface of the right lobe, and the front of the 2nd part of the duodenum, passing to the anterior surface of the right kidney, where it becomes continuous with the part already traced. To the left of the longitudinal fissure the peritoneum covers the left lobe of the liver, and is reflected over the front of the cardiac end and fundus of the stomach, whence it passes off to invest the spleen, forming a reduplicature, the gastro- splenic omentum. From the spleen it is continued over the anterior surface of the left kidney, forming the posterior

i98 THE POCKET ANATOMY

layer of the lieno-renal ligament, and over the descending colon to join the part already described.

Between the liver, stomach, and transverse colon is a diverticulum of the main peritoneal sac, which communicates with the larger peritoneal cavity through the foramen of Win- slow. To understand the disposition of the layers one has only to imagine the smaller sac to have been invaginated through the foramen of Winslow inwards and behind the stomach, and the arrangement becomes clear.

The two sacs traced vertically.

From transverse fissure of liver, two layers pass : —

To small curvature of stomach.

Two layers separate, one passing in front and the other behind stomach, thus enclosing it.

Join together at great curvature, forming anterior layers of great omentum.

Pass down in front of and beyond transverse colon.

Bend upwards and backwards, and separate to enclose transverse colon ; continue together to the posterior abdominal wall, until opposite the anterior border of the pancreas, where they part, one layer passing upwards, and the other down- wards.

The ascending layer passes : —

Over upper surface of pancreas and posterior part of diaphragm.

Then on to posterior surface of liver to the transverse fissure.

The descending layer passes : —

Along superior mesenteric vessels, round jejunum and ileum, and back to spine, forming mesentery.

Downwards in front of spine, lower part of aorta and sacral promontory.

Over pelvic colon, forming pelvic meso-colon.

Forwards. Male. — To bladder, forming recto-vesical pouch and

posterior false ligaments.

Female. — To vagina and uterus, forming posterior liga- ments of uterus and recto-vaginal pouch. Then over uterus to bladder, forming utero-vesical pouch and posterior vesical ligaments.

Over bladder to anterior abdominal wall, covering urachus and obliterated hypogastric arteries as far as umbilicus.

Over under surface of diaphragm.

Reflected over upper surface of liver.

THE PERITONEUM 199

Round anterior border of liver to under surface as far as transverse fissure.

The two sacs traced horizontally, at the level oj the foramen of Winslow.

From falciform ligament of liver : —

Over anterior abdominal wall and diaphragm.

Over outer part of left kidney.

Reflected outwards behind splenic vessels to spleen, forming posterior layer of lieno-renal ligament.

Over spleen as far as hilum.

To stomach, forming anterior layer of gastro-splenic omentum.

Over anterior wall of stomach into anterior layer of gastro- hepatic omentum.

Turns round hepatic artery, forming anterior edge of foramen of Winslow (here the smaller sac commences).

Passing from right to left : —

Forms posterior layer of small omentum.

Over posterior surface of stomach.

Forms posterior layer of gastro-splenic omentum, reaching hilum of spleen.

Forms anterior layer of lieno-renal ligament.

Passing now from left to right : —

Continues over left kidney, aorta, and inferior vena cava, here forming posterior boundary of foramen of Winslow (here smaller sac ends, and large sac again commences).

Over right kidney to liver.

Over under-surface of liver to left border, round which it may be traced over anterior surface, to falciform ligament.

SYNOPSIS OF PROCESSES OF THE PERITONEUM.

Omenta — folds connected with the stomach.

Lesser or Gastro-hepatic Omentum. — From transverse fissure and fissure for ductus venosus on liver to small curvature of stomach and ist part of duodenum. Right border free, forming anterior boundary of foramen of Winslow.

Great or Gastro-colic Omentum. — Formed, as shown above, by the passing downwards and then folding upwards of the two layers passing from stomach, and thus encloses the lower part of the cavity of the smaller sac of the peritoneum.

Gastro-splenic Omentum. — Passes from fundus of stomach to hilum of spleen, and contains the splenic vessels be- tween its layers. Below it is continuous with the great omentum.

200 THE POCKET ANATOMY

Mesenteries — folds connecting intestine to posterior ab- dominal wall.

The Mesentery. — Attached behind to left side of 2nd lumbar vertebra, passing downwards across vertebras to right sacro- iliac synchondrosis. Contains superior mesenteric vessels, jejunum and ileum between its layers. The upper layer is continuous with inferior layer of transverse meso-colon, the lower layer with peritoneum on posterior abdominal wall.

Transverse Meso-colon.— Formed by junction of two ascend- ing layers of great omentum after they have enclosed transverse colon; at the spine the two layers separate, as explained, into ascending and descending layers.

Pelvic Meso-colon. — A long process attached to brim of pelvis.

Ligaments. — The peritoneum, as explained, is reflected from the abdominal walls to viscera, forming ligaments.

Ligaments of the Liver : —

Suspensory or Falciform. — Sickle-shaped fold passing from anterior abdominal wall to upper and anterior surfaces of liver. The inferior free border contains obliterated umbilical vein or round ligament.

Coronary. — Connects right lobe to diaphragm ; consists of two layers, the anterior being derived from greater sac, and the posterior from lesser sac.

Lateral (2). — These are the right and left ends of the coronary ligament.

Ligaments (False) of the Bladder : —

Posterior False Ligaments (2). — The edges of the recto-vesical pouch.

Lateral False Ligaments (2). — Reflection from sides of bladder.

Superior False Ligament. — Reflection from bladder to anterior abdominal wall along urachus.

Ligaments of the Uterus : —

Broad Ligaments (2).— Each passes from side of uterus to lateral pelvic wall : contains between its folds the round ligament, Fallopian tube, the ovary, and its ligament and branches of ovarian and uterine vessels.

Anterior Ligaments (2). — Margins of utero-vesical pouch.

Posterior Ligaments (2). — Margins of recto-vaginal pouch.

Ligament of Spleen, or lieno-renal ligament, passes from left kidney to spleen ; the right or anterior layer is formed by the lesser sac, and the left or posterior by the larger one.

Behind,	Above.	Below.
Between the layers of the	Inferior vena cava. Right crus of	Caudate lobe.	ist part of duodenum. Commence- ment of
small omentum.	diaphragm.		hepatic ar- tery.

THE MEDIASTINA 201

Costo-colic ligament (vide p. 191.)

The foramen of Winslow is the orifice behind the right free margin of the small omentum, by which the smaller peritoneal sac communicates with the general peritoneal cavity.

Relations : —

In Front.

Hepatic artery. Portal vt-.in. Common bile-duct.

THE MEDIASTINA.

The superior mediastinum is the space above the peri- cardium extending upwards to the root of the neck.

Boundaries : —

Above. Superior aperture of the thorax.

Below. Plane passing from lower part of body of 4th dorsal vertebra, to the junction of the gladiolus and manubrium of sternum.

In front. Manubrium and origins of sterno-hyoid and sterno- thyroid muscles.

Behind. First four dorsal vertebrae, and lower ends of longi

coin.

Laterally. The parietal or mediastinal pleura, passing back from posterior surface of sternum to vertebrae.

Contents. Trachea (lower end), oesophagus, thoracic duct, transverse part of arch of aorta, innominate artery, thoracic part of left carotid and subclavian arteries, innominate veins, upper part of superior vena cava, phrenic and pneumogastnc nerves, left recurrent laryngeal and the cardiac nerves, lymphatic glands and remains of thymus gland.

The anterior mediastinum is the space between the two pleurae in front of the pericardium ; it is narrow above, but broader below.

Boundaries : —

In front. Sternum, with 5th, 6th, and part of yth left costal cartilages, triangularis sterni, and left internal mammary vessels.

Behind Pericardium.

T..iterallv Pleura

202 THE POCKET ANATOMY

Contents. Anterior mediastinal glands.

The middle mediastinum contains the pericardium with its contents, the phrenic nerves and accompanying vessels, the arch of the vena azygos major, the roots of the lungs and bronchial lymphatic glands.

The posterior mediastinum lies behind the pericardium.

Boundaries : —

In front. Pericardium and roots of lungs, and diaphragm (below).

Behind. Spinal column, from the lower border of the 4th dorsal to the i2th dorsal vertebra.

Laterally. Pleura.

Below. Diaphragm covered by pleura.

Above. Plane passing forwards from lower border of 4th dorsal vertebra.

Contents. Descending thoracic aorta and some of its right intercostal branches, ossophagus, pneumogastric and great splanchnic nerves, the three azygos veins, thoracic duct, and posterior mediastinal glands.

THE HEART AND PERICARDIUM

THE PERICARDIUM.

The pericardium is a nbro-serous membrane, containing the heart and the commencement of the great vessels. The apex points upwards and surrounds the ascending aorta, superior vena cava, and pulmonary artery for about 2 inches — i.e., to the level of the lower border of the aortic arch. The base is fixed to the central tendon and adjoining muscular fibres of the diaphragm.

In front. Behtnd. Laterally.

Gladiolus. Roots of lungs. Pleura.

Left costal car- CEsophagus. Comes nervi phre-

tilages (4th to Descending aorta. nici vessels.

yth). Phrenic nerve.

Remains of thy-

mus gland. Overlapped by

both lungs and

pleurae.

THE HEART AND PERICARDIUM 203

The serous layer of the pericardium lines the inner surface of the pericardium, and is continued on to the surface of the heart, being also prolonged over the vessels in the pericar- dium. The aorta and pulmonary artery are enclosed in one sheath, and it surrounds the ends of the four pulmonary veins, forming a pouch posteriorly between the veins of the right and left sides. The part of the superior vena cava within the pericardium is also invested by it.

The serous layer forms a reduplicature above and in front of the root of the left lung, enclosing the hbrous remains of the left superior vena cava ; it reaches from the left superior inter- costal vein downwards to the side of the left auricle, where it joins the serous investment round the left upper pulmonary vein. This reduplicature is known as the vestigial fold of Marshall.

THE HEART.

The heart is a hollow muscular organ enclosed in the pericardium, and having an irregular conical shape. It is attached at its base to the great bloodvessels, being otherwise free within the pericardial sac.

Position. — The heart is placed obliquely, the base being directed upwards, backwards, and to the right; the apex downwards, forwards, and to the left. The apex corresponds to a point in the 5th left intercostal space 3^ inches from the mid-line.

The Limits of the Heart.

Superior. Line from lower border of 2nd left, to upper border of 3rd right costal cartilage.

Inferior. Line from yth right chondro-sternal articulation to apex.

Right side. Line drawn nearly vertically i£ inches from mid-line of sternum, from upper to lower limit.

Left side. Line from lower border of 2nd left costal cartilage, i inch from sternum, downwards and to the left to apex.

Position of the Valves.

Pulmonary. Opposite upper border of 3rd left costal carti- lage near sternum.

Aortic. Opposite left £ of sternum, on level with lower border of 3rd costal cartilage.

Tricuspid. Opposite right £ of sternum, on level with 4th intercostal space

204 THE POCKET ANATOMY

Mitral. Opposite junction of 4th left costal cartilage with sternum.

Divisions. — The heart is divided longitudinally by a septum into two halves, right and left, each of which is subdivided transversely into two cavities. Those four divisions are indicated on the heart's surface by grooves. Two longitudinal grooves, one situated on the anterior and the other on the posterior surface, indicate the lateral division, whilst a trans- verse furrow, the auricula-ventricular groove, indicates its separa- tion into auricles above the furrow and ventricles below it.

The Circulation. — The right auricle receives venous blood from the vense cavae and coronary sinus ; thence it passes into the right ventricle, whence it is conveyed to the lungs by the pulmonary artery. After being oxygenized the blood passes into the left auricle by the pulmonary veins ; thence it is conveyed into the left ventricle, and from there to the aorta, whence it passes through the body.

THE CAVITIES OF THE HEART.

The RIGHT AURICLE consists of a principal cavity and an appendix auriculae.

The principal cavity, or sinus venosus, is of an irregular form.

The appendix auricula is a small muscular pouch projecting from the anterior and upper angle of the auricle overlapping the root of the pulmonary artery.

At the junction externally of the two cavities is seen a well-marked groove (sulcus terminalis), which on the interior appears as a ridge (crista terminalis of His) .

Openings in the sinus. — Superior vena cava, in the upper and front part. Inferior vena cava, at the lower and back part of the auricle. Between the openings of the two cavae is a muscular projection, the tubercle of Lower.

The coronary sinus opens between the inferior vena cava and the auric ulo-ventricular opening.

Foramina Thebesii are the mouths of small cardiac veins.

The auricula-ventricular opening is in front of the inferior cava.

Openings of anterior cardiac veins (2 or 3) from the surface of the right ventricle.

Valves. — The Eustachian valve is a semilunar fold of endo- cardium in front of the anterior margin of the inferior vena cava ; passes upwards and to the left to anterior margin of annulus ovalis.

THE HEART AND PERICARDIUM 205

The coronary valve, or valve of Thcbesius, protects the open- ing of the coronary sinus.

Remnants of foetal structures. — The Fossa ovalis is the remains of the foramen ovale on the lower and posterior part of the septum auricularum, just above and to the left of the opening of the inferior vena cava.

The annulus ovalis is the upper crescentic elevated margin of the fossa.

The musculi pectinati are the prominent muscular columns running over the surface of the appendix auriculae.

The endocardium is smooth in the main part of the cavit)', but irregular over the musculi pectinati of the auricu- lar appendix.

The RIGHT VENTRICLE consists of a cavity, the upper and left angle of which is prolonged into a funnel-shaped canal, the infundibulum or conus arteriosus, leading to the pulmonary artery. On the wall (except in the infundibulum, which is smooth) are projections, column® carnea, formed of muscular bundles, of which there are three varieties : the first are merely prominent ridges ; the second are attached at the ends, being free in the middle ; the third are the musculi papillares, which project inwards, and are attached by their bases to the wall of the ventricle, the other end being connected with the chorda tendinea, or cords attached to the flaps of the auriculo- ventricular valve.

The tricuspid valve, which guards the right auriculo-ventricu- lar opening, consists of three cusps, formed by a reduplication of the endocardium, with some fibrous tissue enclosed. The bases of the flaps are attached to the fibrous ring of the auriculo- ventricular orifice, while to their free ends are attached the chordae tendineae.

Position of cusps. Right one against right wall of ventricle (marginal cusp). Posterior one between auriculo-ventricular opening and septum (septal cusp). Left between auriculo ventricular and pulmonary orifices (infundibular cusp). The valve prevents regurgitation of blood into the auricle during the heart's contraction.

The opening of the pulmonary artery is at the summit of the funnel-shaped infundibulum, and is guarded by the pulmonary semilunar valves. The semilunar valves are three folds of the lining membrane, aright, left, and posterior, which guard the orifice of the pulmonary artery. The free margin of each has in its middle a small fibrous nodule, the corpus Arantii, and between each valve and the beginning of the pulmonary artery is a dilatation called the pulmonary sinus, or sinus of

206 THE POCKET ANATOMY

Valsalva. The point corresponding externally to these valves is the upper border of the junction of the third left costal cartilage with the sternum.

The LEFT AURICLE consists of a principal cavity and an appendix auriculae ; the latter extends forwards and to the right side, projecting over the commencement of the pul- monary artery. Its interior presents musculi pectinati as on the right side.

OPENINGS. — The pulmonary veins (4) open into the cavity, two on either side.

The auricula-ventricular opening is smaller than that on the right side.

On the septum may be seen a shallow depression, the re- mains of the foramen ovale.

The LEFT VENTRICLE is longer and more conical than the right, with its walls nearly three times as thick. The interior contains columnae carneae, musculi papillares, and chordae tendineae, as on the right side.

OPENINGS. — The auricula-ventricular opening corresponds to the junction of 4th left costal cartilage with the sternum ; it is closed by the mitral valve, which is attached to the circum- ference at the opening, similarly to the tricuspid. It consists of two flaps, the larger being anterior (aortic cusp).

The aortic opening is placed in front and to the right side of the preceding, and its position may be marked externally by a line drawn through left half of the sternum, on a level with the lower border of the 3rd left costal cartilage. The orifice is guarded by three semilunar valves, which are precisely similar to those on the pulmonary artery, the characteristics of which are, however, better marked ; they are named from their position anterior, right posterior and left posterior.

The endocardium is the serous membrane lining the whole of the interior of the heart, and is continuous with the lining membrane of the bloodvessels.

The coronary arteries supply the substance of the heart.

The right coronary artery comes off from the anterior sinus of Valsalva (aortic), passes on the right side of the pulmonary artery, between it and the right appendix, then backwards along the right auriculo-ventricular groove as far as the posterior inter-ventricular groove, where it divides into two branches, one of which passes transversely in the left auriculo- ventricular groove and joins branch of left artery, whilst the other passes downwards in the posterior inter-ventricular groove to supply the ventricles and septum ; anas descending branch of left artery

ORGANS OF VOICE AND RESPIRATION 207

The left coronary artery arises from the left posterior sinus of Valsalva. It passes behind and then to the left of the pul- monary artery, and divides it into two branches, one of which passes forwards and downwards in the anterior inter-ventri- cular groove, and the other to the left and backwards along the left auriculo-ventricular groove.

The cardiac veins return the blood from the muscular wall mainly through the coronary sinus into the right auricle (p. 106).

The nerves come from the cardiac plexuses.

ORGANS OF VOICE AND RESPIRATION.

THE LARYNX.

The larynx lies in the front and upper part of the neck, being placed below the tongue and hyoid bone and between the large vessels of the neck. It opens above into the pharynx and below into the trachea. It is subcutaneous in the middle line, being covered only by skin and cervical fascia ; but laterally it is overlaid by the insertions of the sterno-hyoid and sterno-thyroid, by the thyro-hyoid and origin of the inferior constrictor. Is composed of cartilages held together by ligaments, and moved by muscles, the whole being lined with mucous membrane.

The cartilages of the larynx : —

The thyroid cartilage is the largest, consists of two wings or alae united in front at an acute angle, and forming the projection known as the pomum Adami.

Outer surface : traversed by oblique line, passing upwards and backwards, giving attachment to sterno-thyroid and Ihyro-hyoid muscles, and below oblique line to inferior constrictor.

Inner surface : presents in the middle line at the junction of right and left ala, the receding angle, to which are attached the root of the epiglottis, the superior and inferior thyro-aryte- noid ligaments, the thyro - arytenoidei and thyro-epiglottidei muscles.

Superior border ; sinuous ; connected to hyoid bone by thyro-hyoid membrane ; the two meeting together anteriorly in the mid-line form notch above pomum Adami.

Inferior border : connected with upper border of cricoid by crico- thyroid membrane anteriorly, and by crico-thyroid muscle laterally.

Posterior border : thick and rounded, receives insertion of

2o8 THE POCKET ANATOMY

stylo- and palato-pharyngei muscles, prolonged upwards into superior cornu, which passes up wards, backwards, and inwards, having lateral thyro-hyoid ligament attached to tip ; and downwards into inferior cornu, shorter, passing downwards, forwards, and inwards, presenting on inner surface a small facet to articulate with cricoid.

The cricoid cartilage : shaped like signet ring, deep behind and shallow in front.

Outer surface: anterior half gives attachment to crico- thyroid muscles, and behind this to part of inferior con- strictor. Posterior half, broad and thick, presents ridge in middle line for attachment of some longitudinal fibres of oesophagus ; on each side of ridge, a depression giving attach- ment to the crico-arytenoideus posticus, and external to this a small facet for articulation with inferior cornu of thyroid.

Inner surface : smooth, lined with mucous membrane.

Superior border : inclines from the front, upwards and back- wards, gives attachment anteriorly and laterally to crico- thyroid membrane and crico-arytenoideus lateralis. Presents posteriorly in mid-line a notch, on each side of which is a facet for articulation with arytenoid cartilage.

Inferior border: horizontal, connected with ist ring of trachea by intervening membrane.

Arytenoid cartilages : are two small pyramidal cartilages, articulating with posterior part of upper border of cricoid.

Antero-external surface : convex and rough, receives attach- ment of thyro-arytenoideus muscle and false vocal cord. At upper end is a tubercle for superior thyro-arytenoid ligament, and below an oblique ridge.

Posterior surface : hollowed for attachment of arytenoideus muscle.

Internal surface : narrow and smooth, covered with mucous membrane.

Base : has concave facet on under surface for articulation with cricoid cartilage, and prolonged into three angles.

External or muscular process : short and prominent, gives attachment to lateral and posterior crico-arytenoid muscles.

Anterior or vocal process : long and pointed, gives attach- ment to true vocal cord.

Internal : rounded.

Apex : looks backwards and inwards, surmounted by the cartilage of Santorini.

Cartilages of Santorini or cornicula laryngis : two small cartilages- of conical shape, each attached to the apex of an arytenoid cartilage, and giving attachment to the aryteno- epiglottidean fold.

ORGANS OF VOICE AND RESPIRATION 209

Cuneiform cartilages, or cartilages of Wrisberg, are two

small cartilages, one on each side, found in the aryteno- epiglottidean fold.

The epiglottis covers the superior aperture of the larynx ; it is a leaf-shaped lamina of yellow nbro-cartilage.

Apex: attached to receding angle of thyroid by thyro epiglottic ligament.

Base : broad, rounded, and free ; directed upwards.

Anterior surface: covered in upper part by mucous mem- brane, which passes forwards as the three glosso-epiglottic folds to connect it with the tongue ; below it is attached to the hyoid bone by hyo-epiglottic ligament.

Posterior surface : covered by mucous membrane, concave from side to side, concavo-convex from above downwards; the convex part is known as the cushion or tubercle of the epiglottis.

The LIGAMENTS of the larynx are : —

The thyro-hyoid membrane : passes from the upper border of the thyroid cartilage to the upper border of the posterior surface of the hyoid bone: between it and the posterior surface of the hyoid bone is a synovial bursa. It is pierced by the superior laryngeal vessels and internal laryngeal nerve of each side.

(The lateral thyro-hyoid membrane is the posterior edge of the preceding, passes from the superior cornu of the thyroid to the tip of the great cornu of the hyoid bone, in which is found a small cartilaginous nodule, the cartilage triticea.)

The crico-thyroid membrane connects the thyroid and cricoid cartilages. Consists of two parts : —

Central: thick, triangular, with base down wards, passingfrom lower border of thyroid to upper border of cricoid cartilage.

Lateral : thinner, passes from upper border of cricoid car- tilage internally to ala of thyroid, ending in a free border, the true vocal cord, or inferior thyro-arytenoid ligament.

The superior thyro - arytenoid ligaments are attached anteriorly to the angle between the alae of the thyroid cartilage, just below the epiglottis, and posteriorly to the anterior surface of the arytenoid cartilage. They lie within the mucous membrane, forming the false vocal cords.

The inferior thyro-arytenoid ligaments are attached an- teriorly to the angle between the alae of the thyroid cartilage, and posteriorly to the anterior process at the base of the arytenoid cartilage. The inner free edge, covered with mucous membrane, forms the true vocal cord, and below it is continuous with the lateral part of the crico-thyroid ligament.

210 THE POCKET ANATOMY

Capsular ligaments, lined with synovial membrane, sur- round the articulations between the cricoid and inferior cornua of the thyroid, and also between the cricoid and two arytenoid cartilages.

The hyo-epiglottic ligament connects the lower part of the anterior surface of the epiglottis to the upper border of hyoid bone.

The thyro-epiglottic ligament connects the apex of the epiglottis to the upper part of the receding angle of the thyroid cartilage.

THE INTERIOR OF THE LARYNX.

The cavity of the larynx extends from the superior aperture to the lower border of the cricoid cartilage. The vocal cords form an imperfect diaphragm, dividing the cavity into two parts. The chink between the true vocal cords is the glottis or rima glottidis, which is the narrowest part of the larynx. The whole is lined by mucous membrane.

The superior aperture of the larynx is triangular in shape. with base directed forwards. In front is the epiglottis, behind are the summits of the arytenoid cartilages and cornicula, and, laterally, the aryteno-epiglottic folds pass between the lateral edges of the epiglottis backwards to the tips of the arytenoid cartilages and cornicula, enclosing the cuneiform cartilages.

The superior or false vocal cords, one on each side, are two folds of mucous membrane enclosing the superior thyro- arytenoid ligaments ; each is placed above the corresponding ventricle.

The inferior or true vocal cords, one on each side, are attached in front to the receding angle of the thyroid carti- lage, and behind to the anterior angle or vocal process at the base of the arytenoid cartilage. They are formed of mucous membrane, enclosing the inferior thyro-arytenoid ligaments.

The ventricles of the larynx are the fossae between the false and true vocal cords ; the anterior part of each ventricle is prolonged upwards between the false vocal cord and the ala of the thyroid cartilage into a pouch, the sacculus laryngis. The opening of the sacculus into the ventricle is narrow, and its cavity contains numerous small glands.

The muscles of the larynx have been described (vide pp. 30 and 31).

The arteries of the larynx are the laryngeal branches of the superior and inferior thyroid.

ORGANS OF VOICE AND RESPIRATION 211

The nerves are the superior laryngeal, the inferior or recurrent laryngeal, and branches of the sympathetic of each side.

THE TRACHEA.

The trachea extends from the lower border of the larynx (opposite the lower border of 5th cervical vertebra) to the level of the disc between the 4th and 5th dorsal vertebrae, there dividing into the two bronchi. In length it measures 4^ inches.

Relations in the Neck.

In front. Skin.

Superficial and deep fasciae. Anastomosis of anterior jugular veins.

Isthmus of thyroid gland. Inferior thyroid veins.

Laterally.

Cervical fascia.

Common carotid artery.

Lateral lobe of thyroid gland.

Inferior thyroid artery.

Recurrent laryn- geal nerve.

Behind. QEsophagrs.

In the Thorax.

In Front. Right Side.

Manubrium Right pneumo- sterni. gastric nerve.

Innominate ar-

tery. Pleura.

Left Side. Left cardiac nerves. Left pneumogastric

nerve. Left recurrent

laryngeal nerve. Aortic arch. Left subclavian m-

tery. Pleura.

Posteriorly.

(Esophagus.

Origin of sterno

mastoid. Origins of sterno-

t hy roid and

sterno-hyoid. Remains of thymus

gland. Left innominate

vein. Commencements of

innominate and

left carotid ar- teries.

Arch of aorta. Deep cardiac

plexus.

The cartilages, from sixteen to twenty in number, are U-shaped, the anterior § or convex part being cartilage, the posterior j fibrous membrane.

14—2

212 THE POCKET ANATOMY

The right bronchus, about i inch long, is shorter, more vertical in direction, and of larger calibre than the left. It passes from the trachea downwards and to the right on a level with the 5th dorsal vertebra to the root of the corre- sponding lung, lying at first above and then behind the right pulmonary artery. The superior vena cava and right phrenic nerve lie in front, and the venaazygos major arches forwards above it.

The left bronchus is nearly 2 inches long, and passes down- wards and forwards under the arch of the aorta to the root of the left lung, joining it at the level of the upper border of 6th dorsal vertebra. Behind it are the oesophagus, thoracic duct, and descending aorta. It lies at first behind, and then below, the left pulmonary artery.

THE LUNGS AND THE PLEURAE.

The lungs, two in number, occupy the whole of the thorax except the mediastina (vide pp. 201 and 202), which separate them from each other. They are conical in shape, and are covered with pleura. Each lung is free except at the median part or root, where it is attached to the bloodvessels and bronchi.

The pleurae are two serous sacs enclosing and investing the lungs. Each pleura consists of a visceral and parietal layer. The visceral portion covers the lung, and the parietal layer lines the inner surface of the chest walls, the upper surface of the diaphragm, and the sides of the pericardium. The visceral layer of each pleura becomes continuous with the parietal layer in front and behind the root of the lung ; and below the root a fold, the ligamentum latum pulmonis, extends down- wards along the inner surface of the lung to the diaphragm. The mediastina are formed by the visceral layers of each side approaching one another towards the median line.

The limits of the parietal pleurae are as follows: each extends upwards into the neck, forming a dome-like process over the apex of the lung about 2 inches above the anterior end of the first rib ; from this each pleura passes down- wards and forwards to the posterior aspect of the sterno- clavicular joint and meets its fellow in the mid-line at the manubrio-gladiolar articulation ; they pass down together to level of 4th costal cartilages, where right pleura passes verti- cally to level of yth right costal cartilage in mid-line ; then outwards, crossing gth rib in mid-axillary line ; then down- wards and backwards along nth rib to reach spine at neck of

ORGANS OF VOICE AND RESPIRATION 213

rath rib. Behind, it passes upwards on right side of bodies of vertebras to apex. At level of 4th costal cartilage the left pleura arches outwards, leaving uncovered part of anterior surface of pericardium, and lying about f inch from the margin of sternum, to reach yth left costal cartilage, below which it follows same line as on right, but is placed at a slightly lower level.

THE LUNGS.

Each lung is cone-shaped, with the base downwards.

The apex projects upwards into the root of the neck behind the clavicle and anterior scalene muscle. Above the first rib, the first part of the subclavian artery lies in front, being separated from it by the pleura.

The base is concave, resting upon the diaphragm, and following the attachment of the midriff is placed lower ex- ternally and posteriorly than anteriorly.

The outer surface is convex, and corresponds to the chest wall.

The inner surface is concave, corresponding in part to the convex outer surface of the pericardium. It presents about its middle, and towards the posterior part, a slit, the hilum pulmonis, where the bronchi and vessels pass in to form the root.

The anterior margin is thin, and overlaps the pericardium, and presents on the left side a notch for the apex of the heart.

The posterior margin is rounded, and occupies the groove by the side of the vertebrae.

Fissures and Lobes. — The left lung is smaller and narrower than the right, and is divided into an upper and lower lobe by a fissure, which passes upwards and backwards from the anterior border nearly to the root. The right lung is larger and shorter than the left, and is divided into three lobes, upper, middle, and lower, by two fissures. One fissure passes obliquely from the outer surface upwards and inwards nearly to the root, and the second passes horizontally from the middle of the first, forwards to the anterior margin, cutting off a middle triangular lobe.

Each root consists of the corresponding bronchus, a branch of the pulmonary artery, two pulmonary veins, nutritive bronchial vessels, anterior and posterior pulmonary plexuses, lymphatic vessels and glands, all held together by areolar tissue, and covered by the pleura.

2i4 THE POCKET ANATOMY

Relations of the right root : —

In Front. Behind. Atm*. Below.

Right phrenic Right pneumogas- Vena azygos Ligament -.im

nerve. trie nerve. major. latum pu:.

Superior vena cava. Vena azygos major. m o n i s. Part of right

auricle.

Relations of the left root : —

In Front. Behind. Above. Below.

Left phrenic nerve. Descending thoracic Arch of Ligamenturr

aorta. aoita, latum pul-

CEsophagus. munis. Thoracic duct. Left pneumogastric

Position of the constituents of the root : — From before backwards in each lung : — Pulmonary veins. Pulmonary artery. Bronchus.

From above downwards :— -

Right side. Left side.

Bronchus. Pulmonary artery.

Pulmonary artery. Bronchus.

Pulmonary veins. Pulmonary veins.

THE PULMONARY ARTERY.

The pulmonary artery conveys venous blood from the right side of the heart to the lungs. It is 2 inches long, and com- mencing at the infundibulum of the right ventricle, is directed upwards in front of ascending part of aorta, and in same tube of pericardium, then passes upwards and backwards on left of ascending aorta to reach the concavity of the aortic arch, where it divides into right and left branches for the lungs. Near the bifurcation a fibrous cord, the ligamentwn arteriosum, passes from the left branch to the under surface of the aorta. It is the remains of the ductus arteriosus in the foetus.

Relations (contained in same sheath of pericardium with ascending aorta) : —

DUCTLESS GLANDS ON THE TRACHEA 215

In Front. Pericardium. Left pleura and lung.

Behind. Ascending aorta. Left auricle.

Above. Transverse aorta. Ligamentum ar- teriosum.

Laterally. Coronary artery. Auricular appen- dix. Ascending aorta (right side).

The right pulmonary artery is longer than the left, passes to the root of the right lung, behind the ascending aorta and superior vena cava, where it divides into three primary branches, one for each lobe.

The left pulmonary artery is connected at origin with arch of aorta by ligamentum arteriosum, and passes in front of the descending aorta and left bronchus to the root of the left lung, there dividing into two primary branches for the two lobes.

DUCTLESS GLANDS ON THE TRACHEA.

THE THYROID GLAND.

The thyroid gland is situated on the upper part of the trachea, and consists of two lateral lobes united at lower part by neck or isthmus, which lies over 2nd, 3rd, and 4th rings of trachea and is covered by skin, superficial and deep fasciae, and anterior jugular veins.

Each lobe is conical, with smaller end upwards.

Dimensions. Vertical, i£ inches ; transverse, £ inch ; thick, £ inch.

Relations : —

Antero-external (convex), surface. Deep cervical fascia, sterno- mastoid, sterno - thyroid, sterno - hyoid, and omo-hyoid muscles.

Postero-internal (concave), surface. Upper six rings of trachea, cricoid and thyroid (below oblique line), crico-thyroid and inferior constrictor muscles, inferior thyroid artery, recurrent laryngeal and external laryngeal nerves, oesophagus (on left side) .

Postero-external (convex] surface. Sheath of carotid vessels.

Vessels. Arteries, superior and inferior thyroid ; veins, superior, middle, and inferior thyroid.

THE THYMUS GLAND.

The thymus gland attains its full size at two years, after which it gradually shrinks away. It is situated partly in the anterior mediastinum, and partly in the neck, reaching from level of 4th costal cartilage upwards on trachea as high as

216 THE POCKET ANATOMY

lower border of thyroid gland. It consists of two lateral lobes with occasionally a middle connecting one.

Relations in early life : —

Base. Pericardium.

Behind. Trachea, pericardium, and great thoracic vessels.

In front. Sternum as low as 4th costal cartilages, origins of sterno-hyoid and sterno- thyroid muscles.

Externally. Pleura, sheath of carotid.

Internally. Opposite lobe and side of trachea.

THE URINARY ORGANS.

THE KIDNEYS.

The kidneys secrete the urine, and are situated for the most part in the hypochondriac and epigastric regions of the abdomen behind the peritoneum, extending from the nth rib to within an inch of the crista ilii, the right being placed lower than the left, and lying slightly in the right lumbar and umbilical regions. The average length of each kidney is 4 inches, breadth 2 inches, and thickness i inch. Weight 4^ ounces.

Relations. — The relations of the two kidneys differ some- what ; each is placed so that its anterior surface looks out- wards and the posterior inwards, the upper end being nearer the mid-line than the lower. Each kidney is covered partly on its anterior surface by peritoneum.

Relations of the Right Kidney. In front. Behind.

Right lobe of liver. Diaphragm,

znd part of duodenum. Quadratus lumborum.

Hepatic flexure of colon. Psoas.

(Of which the last two Fasciae covering these areas are non-»peritoneal.) muscles.

Anterior lamella of lumbar

aponeurosis. Last dorsal. \ Ilio-hypogastric, I Nerves.

ilio- inguinal, J ist lumbar artery. Pleura.

Last intercostal space and I2th rib.

THE URINARY ORGANS 217

Relations of the Left Kidney.

In front. Behind.

Fundus of stomach. As on right, except that left

Fostero-internal surface of kidney, lying rather higher, spleen. lies over nth rib.

Tail of pancreas.

Descending colon.

(Of which last two are non- peritoneal.) 9

Above each kidney is the supra-renal body.

Below each kidney is the iliac crest.

The external border is convex, and is directed outwards and backwards.

The internal border is concave, directed well forwards, and at the centre is the fissure or hilum, where the vessels enter and the ureter leaves, lying from before backwards as follows : renal vein, renal artery, ureter.

Each kidney is connected with the bladder by a ureter, which serves to convey urine to the latter viscus ; the top of each ureter is expanded, and forms the pelvis of the kidney, which is divided into three parts called infundibnla, which are subdivided into about 12 calyces. Into these calyces small papilla project, which are the apices of the pyramids of Malpighi. These latter form the medullary substance of the kidney, and are imbedded in the cortical substance, which encloses them completely except at the papillae.

SUPRA-RENAL CAPSULES.

These are ductless glands, resembling in shape a cocked hat, and which embrace the upper extremity of each kidney. The right usually has no peritoneum in front, but the left is covered in front by peritoneum, except where the pancreas crosses it.

Relations : —

A nteriorly — Right. Liver, inferior vena cava, and duodenum. Left. Stomach and lesser sac of peritoneum, pancreas and spleen.

Posteriorly. Diaphragm.

Below. Top of kidney.

THE URETERS.

The ureters connect the kidneys with the bladder, forming the excretory ducts of the former, 12 to 14 inches long.

2i8 THE POCKET ANATOMY

Relations of the Ureter in the Abdomen.

Behind. In front.

Psoas. Peritoneum.

Genito-crural nerve. Colic vessels.

Common or external iliac Spermatic vessels, artery. Ileum (right side).

Pelvic colon (left side).

The right ureter lies close to the outer side of the inferior vena cava.

in the pelvis.

In the Male.— Each ureter enters the fold of peritoneum limiting laterally the recto - vesical pouch (posterior false ligament of bladder) and reaches the base of the bladder, below which it runs downwards and forwards under the obliterated hypogastric artery, crossing the vas deferens externally ; it reaches bladder 2 inches from its fellow and the same distance from prostate ; finally it enters the interiro of the bladder by passing very obliquely through its coats at the posterior angle of the base.

In the Female. — Passes in posterior false ligament of uterus, over side of cervix below uterine artery and lateral to upper part of vagina, to posterior part of base of bladder, and ends as in the male.

THE BLADDER.

The bladder receives the urine from the kidneys by the ureters.

Position. — In infancy it lies partly in the abdomen. In the adult it lies in the pelvis behind the pubes ; in the male in front of the rectum ; in the female it is placed in front of the uterus and vagina.

Differences in the sexes : the female bladder is larger trans- versely.

The apex is connected to the umbilicus by the urachus and by the obliterated hypogastric arteries, the part posterior to the urachus being covered with peritoneum.

The body is uncovered anteriorly by peritoneum, and in front are the triangular ligament, the symphysis and body of the pubis, and pubo-prostatic ligaments. Superiorly it is covered by peritoneum in the upper part, and is in relation with the pelvic colon in the male, and uterus in the female, and with small intestines in both. Crossing

THE URINARY ORGANS

219

obliquely on each side of the bladder is the obliterated hypogastric artery, which marks the lateral limit of its peri- toneal covering ; the vas deferens crosses obliquely the lower part of the lateral surface along the inner side of the ureter and obliterated hypogastric artery.

The base or fundus is directed backwards and downwards.

In the

Rectum, from which it is separated by

Relations of the Base.

Male.

Above.

Recto - vesical pouch of peri- toneum.

Below. Recto-vesical

fascia. Vasadeferentia and

vesiculae semin- , ales.

In the Female. Pouch of Douglas Cervix uteri and

anterior vaginal

wall.

The cervix or neck of the bladder is the part continuous with the urethra, and is embraced in the male by the prostate.

LIGAMENTS. — There are two sets of ligaments of the bladder — true and false.

The true ligaments are two anterior and two posterior. These are formed of recto-vesical fascia, and are described on p. 48. The urachus is usually described as the 5th or superior true ligament.

The false ligaments, five in number, are formed of peri- toneum ; there are two posterior, two lateral, and an anterior, the latter covering the urachus. They have been described on p. 200.

Interior of the Bladder. — Upon the inner surface of the base of the bladder, just behind the urethral orifice, is a triangular smooth surface or trigone, with the apex looking forwards. It is bounded laterally by two ridges passing to. the openings of the ureters, the posterior angles being formed by those openings, placed i£ inches apart; at its apex there is an eJevation, formed by the prostate, called the uvula vesicce, which is i^ inches from the ureters. The mucous membrane over the trigone is smooth, but everywhere else elevated upon the irregular muscular wall and is rugose.

220 THE POCKET ANATOMY

THE MALE ORGANS OF GENERATION.

THE PROSTATE GLAND.

The prostate gland adjoins the neck of the bladder and surrounds the beginning of the urethra, which is placed nearer the anterior than the posterior surface of the gland. It is said to resemble a horse-chestnut in shape, with the apex directed downwards. It measures about i^ inches across its base and i^ inches in depth, and i inch from before backwards, and is held in position by the anterior true ligaments of the bladder.

The prostate is perforated from base to apex by the urethra, into which, as it lies in the gland, the common ejaeulatory ducts open.

Relations : —

Anterior or Pubic Posterior

Base. Apex.

Surface. Surface.

Symphysis pubis. Rectum. Surrounds bladder- Rests on uppei

Anterior ligaments .. . .. neck. layer of tnan-

of bladder. Laterally^ Vesiculae semin- gular ligament.

Dorsal vein of Levator ani. ales.

pens.

Vasa deferentia.

The prostate is surrounded by a sheath derived from the recto-vesical fascia (vide p. 48) and by the prostatic plexus of veins, and is supported by the levator ani.

COWPER'S GLANDS.

Cowper's glands are two small round bodies about the size of a pea, placed behind the membranous part of the urethra, between the two layers of the triangular ligament. Their ducts are about I inch long, and pass forwards, piercing anterior layer of triangular ligament, to open in the bulbous part of the urethra.

THE PENIS.

The penis is divided into a root, body, and glans.

The root is connected to the pubic rami by two strong pro- cesses, the crura, and to the symphysis pubis by the sus- pensory ligament.

The glans forms the extremity ; at its summit is the opening

MALE ORGANS OF GENERATION 221

of the urethra, the meatus urinarius; passing from the lower margin of this is a fold of mucous membrane continuous with the prepuce and called the frenum prtzputii. At the base of the glans is a projecting edge or corona, and behind that a constriction, the cervix. Sebaceous glands (of Tyson) are found on both. The integument of the penis, attached to the neck of the glans, is doubled upon itself, forming the prepuce or foreskin.

The body is the part between the root and the glans, the upper surface being the dor sum.

The corpora cavernosa form the greater part of the body of the penis; they are two cylindrical columns placed side by side, connected together for the anterior f ths, the septum pectiniforme intervening, but separated behind to form the two crura, which are attached to the inner margins of the ischial and pubic rami ; anteriorly the corpora cavernosa fit into the base of the glans. There is a groove on the upper surface for the dorsal vein of the penis and another groove on the lower surface for the corpus spongiosum ; the corpora are attached to the pubic symphysis by the suspensory liga- ment.

The corpus spongiosum commences at the triangular liga- ment by an enlargement, the bulb, and runs forward in the groove on the under surface of the corpora cavernosa, ex- panding over their extremities to form the glans. The bulb lies below the anterior or lower layer of the triangular ligament, and is embraced by the accelerator urinae muscle. The urethra pierces the bulb near its upper surface, and then runs forward in the middle of the corpus spongiosum.

The URETHRA in the male extends from the neck of the bladder to the end of the penis, and has a length of from 6 to 8 inches. It is divided into three parts, according to the structures through which it passes.

(1) The prostatic portion passes through the prostate gland from base to apex ; this part is ij inches long and spindle- shaped : in cross-section it is horseshoe-shaped, with the convexity forwards. On the posterior wall is a longitudinal ridge, the verumontanum or caput gallinaginis, and on each side of this promontory is a depression, the prostatic sinus, into which the prostatic ducts open. Towards the anterior part of the verumontanum is a depression, the sinus pocularis, vesicula prostatica, or utricle, upon the elevated edges of which the ejaculatory ducts open.

(2) The membranous portion extends from the apex of the prostate to the bulb, and is £ inch long anteriorly, but only

222 THE POCKET ANATOMY

£ inch posteriorly from the bulb projecting backwards; it is contained between the layers of the triangular ligament, and is surrounded by the compressor urethrae.

(3) The spongy portion is contained in the corpus spongiosum and occupies the rest of the canal, being from 4 to 6 inches long ; the portion contained in the bulb is somewhat dilated, and the ducts of Cowper's glands open on the floor ; the canal enlarges again iust behind the meatus urinarius, which enlarge- ment is named the fossa navicularis. The lumen of this part of the urethra is transverse, except at the meatus (its narrowest part), where it is vertical.

The floor of the urethra is sprinkled with lacuna, which are the openings of the glands of Littre ; one large one in the fossa navicularis is called the lacuna magna.

THE SCROTUM.

The scrotum contains the testicles and spermatic cords. It is divided in the middle line by a raphe ; the left half is longer than the right, as the left testicle hangs down lower, the left spermatic cord being longer than its fellow.

Coverings of the Testis in the Scrotum : —

1. Skin.

2. Superficial fascia and dartos muscle.

3. Inter-columnar or spermatic fascia.

4. Cremaster muscle and fascia.

5. Infundibuliform fascia, continuous with the transversalis fascia.

6. Tunica vaginalis, consisting of a parietal and visceral layer, forms a closed sac. The visceral layer invests the body and epididymis of the testicle except behind, where the duct and vessels are attached ; at its lateral reflection it is continuous with the parietal layer. It passes, on the outer side, a little between epididymis and body, forming the digital fossa.

THE SPERMATIC CORD.

The spermatic cord consists of the vas deferens with artery to the vas, spermatic artery and pampiniform plexus of veins forming spermatic vein above, sympathetic nerves, the cremasteric artery, the genital branch of the genito-crural nerve, lymphatics, together with some areolar tissue; it extends from the internal abdominal ring to the testis, passing in its course along the inguinal canal, from which it emerges by the external abdominal ring, and thence in front of the

MALE ORGANS OF GENERATION

223

pubes to the scrotum. The vas deferens is placed at the back

of the cord, and may be recognised by its hard and cord-like

feeling.

Boundaries of the Inguinal or Spermatic Canal : —

Extent : i£ inches long, from the internal to the external

abdominal ring

Behind.

Peritoneum and fascia trans- versalis for whole length.

Conjoined ten- don (inner two-thirds).

Triangular fascia.

In Front. Floor formed by

Internal oblique Meeting of Pou-

(outer third). Aponeurosis of external ob- lique (for whole length).

part's liga- ment and fascia trans- versalis.

Rooffonned by Arched fibres of internal oblique and trans versalis, and apposition of layers of abdo- minal wall.

THE TESTES.

The testes are two glandular organs ; each is suspended in the scrotum by the spermatic cord, which is attached to the posterior border. Each testis consists of two parts : the body, which is anterior, and the epididymis, placed posteriorly; to the lower end of this latter the duct or vas deferens is attached.

Coverings of the Testis : —

1. Serous or tunica vaginalis is derived from the peritoneum, and consists of two layers, the visceral and parietal.

2. Fibrous or tunica albuginea covers the body of the testicle, sending in a vertical septum the mediastinum or corpus High- ntori : this latter gives off secondary processes or septa, which serve to separate the lobules of the testicle.

3. Tunica vasculosa consists of the bloodvessels, connected together with areolar tissue.

The epididymis is a long narrow body, consisting of three parts, viz. : a superior portion projecting forwards on the upper end of the body, the head or globus major ; a lower, the tail or globus minor, with which the vas deferens is continuous ; and between these two, the body or central portion. The epididymis consists of a duct 20 feet long, exceedingly con- voluted, and bound together by areolar tissue ; it receives the coni vasculosi at the upper part of the testicle.

The body of the testicle consists of numerous lobules of pyramidal shape, which are formed by trabeculae, mediastinum, and tunica albuginea, the base of the lobule being directed 10 the circumference of the testis, and the apex towards the mediastinum. Each lobule contains one or more tubuli semini- /eri held together by areolar tissue. Each tubule commences

224 THE POCKET ANATOMY

near the base, in either a blind extremity or by anastomotic loops, becoming straighter near the apex ; as they enter the mediastinum, they coalesce together to form twenty or thirty tubuli recti.

The tubuli recti or vasa recta pierce the mediastinum, inter- lace, and form the vete testis.

Above twelve to twenty tubules pass from the upper part of the rete as the vasa efferentia.

The vasa efferentia perforate tunica albuginea, being at first straight, then convoluted, and as the coni vasculosi form the globus major.

The coni open into the excretory duct at intervals (when unravelled) of about 3 inches.

The vas deferens commences at the lower part of the globus minor, and ascends along the inner side of the posterior part of the epididymis ; thence it follows the spermatic cord through the inguinal canal and internal abdominal ring. Here it lies under the peritoneum and passes inwards, crossing to the inner side of the external iliac artery, and, entering the pelvis, arches over the superior surface of the bladder, crossing the obliterated hypogastric artery and ureter. At the base of the bladder it runs along the inner side of the vesiculas seminales and loses its peritoneal covering, being separated from the rectum by the recto-vesical fascia, here becoming sacculated ; narrowing again at the base of the prostate, it unites with the duct of the vesicula seminalis of the same side, and forms the common ejaculatoiy duct, which passes forwards through the prostate and opens on the lateral margin of the sinus pocularis into the prostatic urethra.

THE VESICULA SEMINALES.

The vesiculse seminales are two sacculated pouches, placed between the base of the bladder in front and the rectum behind. They are pyramidal in shape, the posterior part being the wider ; anteriorly they converge to enter the prostate near the middle line. The corresponding vas deierens lies on the inner side.

THE FEMALE ORGANS OF GENERATION.

The external organs of generation in the female are : the mons veneris, the labia majora, the labia minora, the clitoris, the meatus urinarius, and the orifice of the vagina. The term vulva includes the whole of these.

FEMALE ORGANS OF GENERATION 225

The mons veneris is the eminence in front of the pubes,

covered with hair.

The labia majora are two prominent folds extending from the mons to the perineum. Externally they are covered with hair and integument, internally with mucous membrane; the labia are joined together anteriorly and posteriorly, forming commissures. A small transverse fold of mucous membrane is found in the posterior commissure called the fourchette ; the space between this and the posterior commissure is known as the fossa navicularis .

The labia minora or nymphse are two folds of mucous membrane, extending for i\ inches downwards and outwards from the clitoris, finally losing themselves below in the labia majora. They surround the clitoris, the upper folds forming the preputium clitoridis, the lower ones, attached o the glands, being the fmnum.

The clitoris, corresponding somewhat in structure to' the penis, is placed just below the anterior commissure. It con- sists of two corpora cavernosa attached to the pubic rami by two crura ; the free extremity or glans is formed by the corpus spongiosum. Between the nymphae, and bounded anteriorly by the clitoris, is the vestibule, at the back part of which the meatus urinanus opens, being about i inch below the clitoris.

The Bulb of the Vestibule. — A mass of erectile tissue lying internal to the nymphas, and resting on the inferior surface of the triangular ligament.

Below the meatus is the orifice of the vagina, closed more or less in the virgin by the hymen, which is a duplicature of mucous membrane, generally semilunar in shape. After its rupture small elevations, carunculcs myrtiformes, only remain.

The glands of Bartholin, analogous to Cowper's glands in the male, are situated on each side near the entrance of the vagina, and their ducts open on the nymphae, external to the hymen.

The urethra in the female is only i£ inches long, and is embedded in the anterior wall of the vagina ; it perforates the triangular ligament, as in the mala. The meatus urinarius, the external orifice of the urethra, opens between the nymphae, about an inch below and behind the clitoris.

The vagina is a dilatable canal, the axis of which is naturally transverse, extending from the vulva to the uterus ; the an- terior wall is about 3^ inches and the posterior wall 4^ inches long. The upper end widens to receive the neck of the uterus, which it meeis at an anglu anteriorly of about 90 degrees.

15

226 THE POCKET ANATOMY

The relations are : —

Anteriorly. Posteriorly. Laterally.

Base of bladder. Perineal body. Broad ligament and

Urethra. Rectum and anal ureter.

canal. Levator ani,

Pouch of Douglas Sphincter vaginse. (upper inch).

There is a ridge or raphe along the middle of the inner surface of both the anterior and posterior walls. The walls likewise present many transverse ridges or ruga. The lower end of the vagina is embraced by the sphincter vaginae.

THE UTERUS.

The uterus or womb is a pear-shaped body, flattened from before backwards, placed in the pelvis between the bladder and rectum ; superiorly it does not reach above the brim of the pelvis. The position corresponds to the pelvic axis. The uterus is covered by peritoneum behind, above, and in front except where it is attached to the base of the bladder ; the peritoneum is reflected from off the sides to the pelvis, forming the broad ligaments. The average length of the uterus is 3 inches, breadth 2 inches, and thickness i inch, and it is, for the pur- pose of description, divided into three parts : —

(1) The fundus is the broad upper end of the body, projecting into the abdomen between the attachments of the Fallopian tubes.

(2) The body extends from the fundus to the neck, narrowing as it approaches the latter ; at the junction of the fundus and body is an angle to which the Fallopian tube is attached ; a little anteriorly to this the round ligament is connected, below and behind this the ovarian ligament is attached.

(3) The neck or cervix uteri is surrounded below by the vagina, into which it projects, forming a vaginal part, which presents a transverse opening, the os uteri externum, bounded by two thick lips, anterior and posterior, of which the anterior is the thicker and the posterior the longer. The part pro- jecting into the vagina is called the portio vaginalis. The sulci in front of the anterior and behind the posterior lips are the anterior and posterior fornices, of which the posterior is much the deeper, and behind is in direct relation with peritoneum (pouch of Douglas).

The cavity of the uterus, flattened from before backwards, is triangular in shape, the superior angles leading to tht.

FEMALE ORGANS OF GENERATION 227

Fallopian tubes. Where the body joins the neck there is a constriction, the os uteri internum.

The ligaments are two anterior or utero-vesical, two pos- terior or recto- vaginal, and two lateral or broad ligaments, all formed of peritoneum.

The broad ligaments are formed of a double layer of peri- toneum passing from the lateral margins of the uterus to the sides of the pelvis. Between the two layers of this ligament on each side are the Fallopian tube, the round ligament, the parovarium, the ovary and its ligament, uterine and ovarian vessels, nerves and lymphatics.

The round ligament is a cord placed between the layers of the broad ligament, extending from the superior angle of the uterus to the internal abdominal ring ; thence it passes into the inguinal canal to lose itself in the labium. It is enclosed for some part of the way in peritoneum, which is known as the canal of Nuck.

THE APPENDAGES OF THE UTERUS.

The Fallopian tubes are two in number, placed in the upper margin of the broad ligament. Each tube measures about 4 inches in length. The cavity commences by a narrow orifice called the ostium internum, and terminates in a fimbriated extremity, which passes over the superior and posterior borders of the ovary, and is attached by the fimbria ovarica to the superior pole of the ovary.

The ovaries are two in number, and correspond to the testes in the male ; they are of a flattened ovoid form, vertically placed in the posterior part of the broad ligament. By its anterior border the ovary is connected to the broad ligament, and by its lower pole to the uterus by a proper ligament, extending to the superior angle of the uterus, and called the ligament of the ovary. The lateral surfaces and posterior border are free. The superior pole and posterior border are embraced by the Fallopian tube ; on its inner surface it is in relation with small intestine in Douglas' pouch, and exter- nally lies in a peritoneal fossa between the external and internal iliac vessels as they diverge. The vessels enter the hilum at the attached anterior border.

The parovarium lies between the Fallopian tube and ovary, and is the remains of the Wolffian body.

15-*

228 THE POCKET ANATOMY

THE NOSE.

The organ of smell consists of an anterior prominent part, situated on the face, and composed of bones, cartilages, muscles, and integument, and two nasal fosses.

The cartilages of the nose are five in number : —

The upper lateral cartilages (2) : situated just below the free margins of the nasal bones. Each cartilage is triangular in shape ; anteriorly it joins its fellow and the cartilage of the septum ; posteriorly it is in connection with the nasal process of the superior maxilla, and inferiorly it joins the lower lateral cartilage.

The lower lateral cartilages (2) are peculiarly curved to form the nostrils, laterally and mesially, being open behind; laterally each cartilage is connected to the nasal process of the superior maxilla by fibrous membrane, in which are two or three sesamoid cartilages ; above it joins the upper cartilage and the cartilage of the septum.

The cartilage of the septum is thicker at the edges than at the centre ; its connections are : anteriorly, with the nasal bones, the two upper lateral cartilages and the lower lateral carti- lages ; posteriorly, with the perpendicular plate of the ethmoid ; inferiorly, with the vomer and the palatal processes of the superior maxillae.

The nasal fossae, separated from each other by the septum nasi, open in front by the anterior nares and behind by the posterior nares. Each fossa may be described as possessing a roof, a floor, an inner and an outer wall.

The roof is formed by the nasal bones, the nasal spine of the frontal, the cribriform plate of the ethmoid, the under surface of the body of the sphenoid, alae of the vomer, sphenoidal processes of the palate bones.

The floor consists of the palatal processes of the superior maxillae and of the palate bones.

The inner wall is made up of the cartilage of the septum, the crest of the nasal bones, the nasal spine of the frontal, the perpendicular plate of the ethmoid, the vomer, the rostrum of the sphenoid, and the crests of the superior maxillary and palate bones.

The outer wall is formed by the nasal process of the superior maxilla, the lachrymal bone, the ethmoid, inner surface of the superior maxilla, the inferior turbinate bone, the vertical plate of the palate bone, and the internal pterygoid plate of the sphenoid.

Meatuso* — The superior and middle turbinate processes of

THE NOSE 229

the ethmoid and the inferior turbinate bone project inwards from the outer wall, dividing each fossa into a superior, a middle, and an inferior meatus.

Openings : —

Superior meatus : sphenoidal and posterior ethmoidal cells.

Middle meatus : anterior ethmoidal cells and frontal sinus, by a common orifice the infundibulum, and antrum of High- more.

Inferior meatus : nasal duct.

The septum is the partition separating the two fossae. It is formed by the perpendicular plate of the ethmoid, the vomer, crest of nasal bones, the nasal spine of the frontal, the rostrum of the sphenoid, the crests of the superior maxillary and palate bones, and the cartilage of the septum. The space between the anterior nares and the anterior edge of the cartilage of the septum is filled by membrane, the columna nasi.

The anterior nares are the anterior openings of the nasal fossae. They are separated from each other by the columna nasi, and within the margin are arranged short stiff hairs, vibrissa.

The posterior nares open backwards into the pharynx. They are oval in shape, being about I inch vertically and £ inch transversely.

Sinuses. — The nasal fossae communicate with the following sinuses in the neighbouring bones, the mucous membrane of the nose being continued into them : —

r. Sphenoidal sinus.

2. Posterior ethmoidal cells.

3. Anterior ethmoidal cells.

4. Frontal sinus.

5. Maxillary antrum.

The mucous membrane lining the cavity of the nose is called the Schneiderian membrane. It is continuous with that of the various sinuses communicating with the nasal fossae, with the conjunctiva through the nasal duct and lachrymal canals, with the mucous membrane of the pharynx through the posterior nares, and with the skin of the face through the anterior nares. On the outer wall, as on the septum, the mucous membrane is inappreciably divided into an upper, olfactory, and a lower, respiratory, part ; the olfactory part consists of the mucosa over the superior and upper part of the middle turbinated, the corresponding part of the septum and the roof of the nose ; the remainder being respiratory.

The epithelium covering the surface consists of three varieties : —

2 jo THE POCKET ANATOMY

1. Stratified squamous, in the region of the nostrils.

2. Columnar, in the olfactory region.

3. Ciliated columnar, in the respiratory region and the sinuses.

The vessels to the nose are the following arteries and veins : spheno-palatine, branches of descending palatine, and arteria septi nasi from facial. The nerves are : olfactory, nasal (first division 5th), naso-palatine, nasal branch of Vidian, nasal branch from anterior palatine and from Meckel's ganglion.

The Olfactory Nerve. — From the olfactory lobe there pro- ceed about twenty branches through the cribriform plate of the ethmoid, which may be divided into three sets : —

1. Inner : pass along the grooves on the septum.

2. Middle : distributed to the roof.

3. Outer: passing to the upper turbinate bone, the anterior part of plain surface of the ethmoid and the middle turbinate bones.

THE EAR.

The ear is divided, for the purpose of description, into three parts, external, middle, and internal.

THE EXTERNAL EAR.

The external er>r consists of the auricle or pinna, and the external auditory meat us.

The pinna is a plate of cartilage covered with integument, and attached to the commencement of the meatus ; it has numerous ridges and depressions, as follows : the external rim is the helix, and anterior and parallel to it is another ridge, the anti helix, which bifurcates above to enclose the fossa of the anti-helix ; between the helix and anti-helix is the fossa of the helix . Anterior to the anti-helix is a depression, the concha; projecting backwards over the meatus is the tragus, and opposite to the latter is the anti-tragus. The lowest part of the pinna, which contains no cartilage, is called the lobule. It is controlled by three muscles (p. 22).

The external auditory meatus reaches from the bottom of the concha to the membrana tympani ; it is i£ inches long. It is arched slightly upwards, and is directed forwards and inwards ; it is formed partly by cartilage and partly by bone. The outer or cartilaginous part is continuous with the pinna, and is about £ inch long. The cartilage does not form a

THE EAR

231

complete tube, being deficient at the upper and back part, the interval being filled by fibrous tissue. One or two fissures (fissures of Santorini) partially traverse the tube. The inner or osseous part is longer than the preceding, and at its inner end there is a groove round the sides and floor for the insertion of the membrana tympani. In the cartilaginous part of the meatus are hairs and ceruminous glands, which latter secrete the ear-wax.

THE MIDDLE EAR OR TYMPANUM.

The tympanum is contained in the temporal bone. It com- municates with the pharynx by the Eustachian tube, and is traversed by a chain of bones, which connect the membrana tympani with the internal ear.

The cavity of the tympanum is bounded externally by the meatus and membrana tympani, internally by the external surface of the internal ear, and it communicates posteriorly with the mastoid antrum.

Thereof (tegmen tympani) is formed by a thin plate of bone separating the tympanum from the middle fossa of the skull.

The floor is formed by the roof of the jugular fossa.

The outer wall is formed by the membrana tympani and the bone around it ; the following fissures are seen : —

The Glaserian fissure : through which the processus gracilis of the malleus and tympanic branch of internal maxillary artery pass.

Aperture of the iter chorda posterius : leading to a canal which opens into the aquseductus Fallopii.

Aperture of the iter chorda anterius : leading to the canal of Huguier, and transmitting the chorda tympani.

The inner wall presents the following : —

The fenestra ovalis : leading into the vestibule, closed by a membrane and the base of the stapes.

The ridge of the aquaductus Fallopii : for the facial nerve placed just above the preceding ; posteriorly it passes down- wards and backwards on the mesial aspect of the large opening of the aditus ad an£nim.

The promontory : placed below the fenestra ovalis, formed by the projection of the first turn of the cochlea.

The fenestra rotunda lies at the bottom of a funnel-shaped depression behind the promontory. It is closed by a mem- brane, the secondary membrane of the tympanum of Scarp a, which closes an aperture in the bone leading to the scala tympani of the cochlea.

232 THE POCKET ANATOMY

The posterior wall presents above the large aperture of the mastoid antrum (aditus ad antrum} and below :

The pyramid which is placed just behind the fenestra ovalis ; it contains the stapedius, the tendon of which projects through the apex.

The anterior wall shows the following : —

The canal for the tensor tympani, opening just anteriorly to the fenestra ovalis.

The processus cochleariformis : a process of bone lying be- tween and separating the canal for the tensor tympani and the Eustachian tube.

The Eustachian tube leads into the pharynx, is partly carti- laginous and partly osseous ; the internal or cartilaginous part is trumpet-shaped, and terminates in an oval opening at the side and upper part of the naso-pharynx. The osseous portion is placed along the angle of union of the squamous and petrous portions of the temporal bone, and is about £ inch long. Below this a thin plate of bone separates the tympanum from the carotid canal.

The membrana tympani is the membrane which separates the external and middle ears. It is inserted into the groove in the osseous portion of the external meatus, and is placed obliquely across the opening, forming with the floor of the meatus an angle of 45°. It contains the handle of the malleus between its layers, which makes the membrane concave ex- ternally. There is a small notch in the upper and anterior part of the groove of insertion known as the notch of Rivini, which is closed by a loose portion of the membrane, the membrana ftaccida of Shrapnell.

Structure of the membrane, from without inwards: —

1. Prolongation of skin of meatus.

2. Fibrous tissue or membrana propria.

3. Mucous membrane of the tympanum.

The ossicles of the tympanum are : —

1. The Malleus.

2. The Incus.

3. The Stapes.

The malleus, or hammer, consists of : —

The head: the thickened upper part, presenting on tne posterior surface a facet for articulation with the body of the i-icus.

The neck : a constriction below the head.

THE EAR 233

The handle: a long tapering process passing downward, and attached by its outer side to the membrana tympani.

The processus gracilis : a slender spicule passing from the neck downwards and forwards into the Glaserian fissure.

The processus brevis : arises from the root of the handle and projects outwards to be attached to the membrana tympani by the anterior and posterior malleal folds which bound the notch of Rivini.

The incus, or anvil, consists of : —

The body : articulating in front by a saddle-shaped facet with the head of the malleus.

The processus brevis : attached to the margin of the mastoid aditus.

The processus longus : passes downwards, behind and parallel to the handle of the malleus. The tip projects inwards, and ends in the orbicular process, which articulates with the head of the stapes.

The stapes closely resembles a stirrup. It consists of: —

The head: looking outwards, and articulating with the orbicular process of the incus.

The base : fixed to the margins of the fenestra ovalis.

The crura : arising from a constricted part, the neck, pass inwards to the extremities of the base. The anterior crus is shorter r-xd straighter than the posterior, and between the two a th.n membrane is stretched.

The ligaments unite the chain of bones to the adjacent walls of the tympanum. They are : —

The anterior ligament of the malleus : passing between the root of the processus gracilis and the edge of the Glaserian fissure. This ligament was formerly described as a muscle passing from the malleus out of the Glaserian fissure, and termed the laxator tympani.

The external ligament of the malleus : passing between the processus brevis and notch of Rivini.

The superior ligament of the malleus : passing between the head of the malleus and the roof of the tympanum.

The ligament of the incus : passing between the processus brevis and the posterior wall of the tympanum.

The annular ligament of the stapes connects the base of the stapes with the edge of the fenestra ovalis.

The muscles : —

The tensor tympani arises from cartilage of the Eustachian tube, and from the bony canal in which it lies. The tendon turns round the end of the processus cochleariformis, and is inserted into the inner border of the handle of the malleus, near its root.

234 THE POCKET ANATOMY

The stapedius is lodged in the aquaeductus Fallopii and pyramid. The tendon issues from the apex of the pyramid, and is inserted in the posterior part of the neck of the stapes.

The mastoid antrum is a large recess placed behind and rather above the tympanum, with which it is connected by the large opening (aditus) before mentioned on the upper part of the posterior tympanic wall ; it is developed with the tympanum and lined by a continuation of its mucous mem- brane. Into it open the mastoid pneumatic cells.

THE INTERNAL EAR OR LABYRINTH.

Within the internal ear are the terminal ramifications oi the auditory nerve. The internal ear or labyrinth is divided into osseous and membranous parts, the former enclosing the latter. Within the membranous labyrinth is a fluid, the endolymph ; arid outside, between the membranous and osseous labyrinths, is a fluid, theperilymph or liquor Cotunnii.

The OSSEOUS LABYRINTH consists of the vestibule, the cochlea, and the semicircular canals.

The vestibule is the central part of the labyrinth. Its outer wall corresponds to the inner wall of the tympanum, and in it is thefenestra ovalis, closed by the base of the stapes ; on its inner wall is a depression, the fovea hemispherica, per- forated by several holes for the branches of the auditory nerve; behind this is a ridge, the crista vestibuli ; and still further back is the internal opening of the aqueduct of the vestibule. On the roof is a depression, the fovea hemi-elliptica. At the posterior part are the five openings of the semicircular canals, and at the anterior part is the apertura scales vestibuli.

The semicircular canals are three arched osseous canals placed above and behind the vestibule, opening into that chamber by five rounded apertures, two adjacent canals having a common opening. Each canal forms about two- thirds of a circle, and presents at one end a dilated part, the ampulla. Two of the canals are vertical, and the third is horizontal.

The siip erior canal is vertical, and forms a projection on the upper surface of the petrous part of the temporal bone. The inner extremity joins the opening of the posterior canal.

The posterior canal is vertical, its upper end being joined to the lower opening of the superior canal.

The horizontal or external canal is the smallest of the three, and lies horizontally just above the level of the fenestra ovalis.

The cochlea is cone-shaped, with the base turned to the

THE EAR 235

internal meatus, £nd the apex opposite the canal for the tensor tympani, and consists of a tapering spiral canal of 2^ turns, with the inner wall formed by its axis or modiolus : the canal is divided into two scalae by a partition of bone and membrane, the lamina spiralis. The enclosed arched extremity of the cochlea is called the cupola, and the first turn of the canal bulging into the tympanum forms the promontory. The lamina spiralis ossea ends at the apex of the cochlea in a small point, the hamulus, between which and the modiolus is a small opening, the helicotrema, by which the two scalae communicate.

The modiolus is pierced by small canals for the passage of nerves, and one larger one, the central canal of the modiolus, passes from the base to the last half-turn of the cochlea. At the base of the lamina spiralis is a small canal, the spiral canal of the modiolus, which winds round the axis, and contains a spiral ganglionated cord, the ganglion spirale.

The scalse are known respectively as the scala tympani and the scala vestibuli.

The scala tympani is the lower one , it commences at the fenestra rotunda.

The scala vestibuli commences at the cavity of the vestibule, and communicates at the apex of the modiolus with the scala tympani, by the helicotrema.

The MEMBRANOUS LABYRINTH consists of sacs containing fluid (endolymph). The ramifications of the auditory nerve are distributed on the wall. These membranous sacs com- plete the septum between the scala tympani and the scala vestibuli, besides enclosing a third space, the scala media or membranous canal of the cochlea.

The membranous vestibule consists of two sacs, the utricle and the saccule.

The utricle or common sinus is larger than the saccule, and is situated in the posterior and upper part of the vestibule, being contained in the fovea hemi-elliptica. The apertures of the membranous semicircular canals open in the posterior part. At the anterior part is a thickened spot, the macula acustica, where the nerves enter. The interior contains, opposite the macula, attached to the wall, a small mass of calcareous grains, known as otoliths, otoconia, or ear sand. Below there is a canal, which, joined to a similar tube from the saccule, extends along the aqueduct of the vestibule, and ends in a dilated pouch, the saccus endo-lymphaticus.

The saccule is smaller and rounder than the utricle, and lies in the fovea hemispherica. Like the utricle, it contains

236 THE POCKET ANATOMY

a macula and a collection of otoliths. Below there is a small canal, canalis reuniens, which connects it with the membranous canal of the cochlea.

The membranous semicircular canals are about one-third the size of the osseous ones, except at the ampullae, where they dilate to nearly fill the bony canal. Each membranous canal is free on the convex surface, the concavity being fixed to the osseous canal. On the part of the internal surface of the ampulla, corresponding to the attachment to the bony canal, is a transverse projection, the crista acustica, in which some filaments of the auditory nerve end.

The membranous cochlea consists of a membranous tube divided into three parts — the scala tympani, scala vestibuli, and canal of the cochlea (ductus cochlearis), which latter contains the organ of Corti, to which the auditory nerve is chiefly distributed.

The lamina spiralis ossea partly divides the spiral canal into the scala tympani and scala vestibuli, the latter being superior. The septum is completed by the membrana basilaris, which is attached to the outer free edge of the lamina spiralis ossea, and passed outwards to the wall of the cochlea, where it is fixed to a thickening of the periosteum called the spiral ligament.

The canal of the cochlea contains the organ of Corti. It lies on the outer part of the scala vestibuli, and is separated from it by the membrane of Reissner, which passes from the lamina spiralis upwards and outwards to the roof of the scala. Thus a triangular piece is cut off, bounded internally by the membrane of Reissner, externally and above by the outer wall of the cochlea, and below by the basilar membrane. The canal of the cochlea is connected below with the saccule by the canalis reuniens, and above it terminates in a blind cone- shaped extremity, partly bounding the helicotrema and fixed to the cupola. The part of the lamina spiralis within the canal of the cochlea becomes thickened, and is called the limbus, and terminates in a concave border, the sulcus spiralis. The basilar membrane is attached to the lower margin of the sulcus spiralis.

The Auditory Nerve. — The auditory nerve divides in the in- ternal auditory meatus into two branches, which perforate the cribriform plate, and are distributed to the cochlea and the vestibule.

The superior or vestibular branch supplies :—

1. The utricle.

2. The ampulla of the superior semicircular canal.

3. The ampulla of the horizontal semicircular canal.

THE EYE AND ITS APPENDAGES 237

The inferior or cochlsar branch is distributed to : —

1. The cochlea.

2. The saccule.

3. The ampulla of the posterior semicircular canal. Nerves of the Cochlea. — The branches of the auditory nerve

destined for the cochlea perforate a number of foramina at the bottom of a spiral groove, the tractus spiralis foraminulen- ttis, placed in the centre of the base of the cochlea. These foramina lead to small canals, which at first pass through the modiolus, and then radiate outwards between the bony layers of the lamina spiralis, so passing to the organ of Corti. In the centre of the tractus spiralis foraminulentus is a larger foramen leading to the central canal of the modiolus, and transmitting nerve filaments for the last half-turn of the cochlea.

THE EYE AND ITS APPENDAGES.

THE APPENDAGES OF THE EYE.

The eye-brows are two arched eminences over each orbit consisting of thickened integuments and muscles, surmounted by hairs.

The eye-lids are two movable folds, an upper and a lower, the upper one being more movable, which by their closure protect the eye from injury. When the eye-lids are open the angles of junction of the upper and lower lids are called re- spectively the external and the internal canthus. In the inner canthus the lids are separated by a small triangular area, the lacus lachrymalis, in which is seen a pink mass of fat and connective - tissue, the caruncula lachrymalis, and which is separated from the eye-ball by a vertical fold of conjunctiva, the plica semilunaris, a rudimentary third eye-lid; opposite the outer edge of the caruncle, on each lid, is the lachrymal papilla, which is pierced by the punctum lachrymals, the external open- ing of the lachrymal canal.

Structure from without inwards : skin, areolar tissue, orbicu- laris muscle (p. 22), tarsal plate, and palpebral ligament, Meibomian glands, and conjunctiva; the upper lid also con- tains the aponeurosis of the levator palpebrse, which is 'attached along the upper margin of the tarsal plate.

The tarsal plates are laminae of condensed connective- tissue found in each lid ; the superior, the larger, is half oval

238 THE POCKET ANATOMY

in shape, the lower a narrow oblong strip. In their substance are lodged the Meibomian follicles. Each tarsal plate is at its edge (except towards the ocular fissure, where it is free) continuous with the membranous sheet known as the palpebral ligament, while internally and externally it receives the tarsal ligaments (p. 22). The superior tarsal plate re- ceives above the main insertion of the levator palpebrse superioris.

The palpebral ligaments form an incomplete diaphragm for the anterior orifice of the orbit ; peripherally they are attached to orbital margin and centrally to edge of tarsal plates.

The conjunctiva is the membrane which forms the most posterior layer of both eye-lids, at the free edges of which it joins the skin. At the base of each eye-lid, where the structures enter its layers, the conjunctiva is reflected on to the eye-ball, the lines of reflection being known as the fomices, of which the superior is the deeper ; into it some fibres of the levator palpebrae superioris are inserted. Over the eye-ball, where it covers the sclerotic, the conjunctiva is loosely connected, some connective-tissue and Tenon's capsule intervening ; but at the corneo-sclerotic margin the conjunctiva is firmly adherent, covering the cornea as its anterior epithelial layer. The conjunctival sac has opening into it above the ducts of the lachrymal gland, and below the openings of the lachrymal canaliculi at the puncta lachrymalia.

The lachrymal gland occupies a depression in the supero- external angle of the orbit ; the anterior margin is connected to the back part of the upper eye-lid. The ducts (12 or 14) open by apertures, placed in a row, on the inner surface of the upper lid.

The lachrymal canals commence at the puncta lachrymalia, which are the openings of the canaliculi, and, arching in the free edge of the lid, pass inwards to open into the lachrymal sac.

The lachrymal sac is placed in a groove formed by the lachrymal bone and the nasal process of the superior maxilla, being behind the tendo oculi, and in front of the tensor tarsi ; it is the dilated upper end of the nasal duct.

The nasal duct, formed by the lachrymal, superior maxilla and inferior turbinal bones, leads from the lachrymal sac to the inferior meatus of the nose, where it opens, the aperture being partly guarded by a valve formed of the mucous mem- brane. It is about £ inch long, and is directed downwards, and slightly outwards and backwards.

THE EYE AND ITS APPENDAGES 239

THE BYE.

The eye-ball is contained within the orbit; its shape is spherical, with the segment of a smaller sphere, corresponding to the cornea, superimposed anteriorly.

The eye-ball consists of three coats enclosing three re- fractive media :

IChoroid. Ciliary body. Iris. yd coat ... ... ... Retina.

The refractive media are : —

1. Aqueous humour.

2. Vitreous body.

3. The lens.

Covering the posterior £ of the eye-ball is a layer of fascia, the capsule of Tenon, continuous posteriorly with the sclerotic at the entrance of the optic nerve, whilst anteriorly at the corneo-sclerotic junction it is connected with it by loose tissue only, and is pierced by the tendons of the muscles of the eye- ball. It is connected with the eye-ball only by delicate con- nective-tissue, the interval constituting an extensive lymph- spa^e and forming a free socket in which the eye-ball glides.

The sclerotic coat is opaque and fibrous, and occupies the posterior £ of the eye-ball, being continuous in front with the cornea, at the corneo-sclerotic junction.

The outer surface is white and smooth, receiving the inser- tions of the recti and obliqui muscles.

The inner surface is of a light-brown colour, due to a lining of pigmented connective-tissue, the membrana fusca, which is connected by fine filaments to the choroid coat. Between the sclerotic and choroid coats is a lymph-space transmitting branches of the ciliary vessels and nerves.

The optic nerve passes through the posterior part of the sclerotic, about $ inch internal to the axis of the eye-ball, the point of perforation being called the lamina cribrosa. At its entrance, the outer sheath of the nerve blends with the sclerotic coat.

The sclerotic is thickest at its posterior part, gradually thinning until about £ inch from the cornea, where it thickens hgain.

240 THE POCKET ANATOMY

Close to the junction of the cornea with the sclerotic is a small circumferential lymph -space, called the canal oj Schlemm.

The bloodvessels of the sclerotic are few in number, but near its junction with the cornea there is a vascular zone derived from the anterior ciliary branches of the ophthalmic artery.

The cornea is the anterior transparent part of the outer coat of the eye-ball, occupying about fc of the circumference of the globe. It projects forward beyond the curvature of the sclerotic, being the segment of a smaller sphere. The posterior surface is concave, and projects further backwards than the anterior convex surface, being overlapped by the edge of the sclerotic ; this surface forms the anterior boundary of the anterior chamber of the eye, containing the aqueous humou-r.

The cornea is clothed on its anterior convex surface by the conjunctiva, which here consists only of an epithelial layer.

At the circumference of the cornea some of the fibres which form its stroma are continued backwards and outwards into the choroid, sclerotic, and iris; those going to the iris are called the ligamentum pectinatum iridis or the pillars of the iris; they form an annular meshwork enclosing a series of lymph-spaces (spaces of Fontana) which communicate with the anterior chamber.

The choroid coat is situated between the sclerotic and the retina, and is the vascular tunic of the eye-ball. It is con- tinued anteriorly into the iris, but before its junction it forms a number of projections, folding inwards, and arranged in a circle, known as the ciliary processes.

The choroid coat is thickest behind, where it is pierced by the optic nerve.

Externally it is connected to the sclerotic by loose connec- tive-tissue traversed by vessels and nerves as before described. Internally it is covered by the pigmented cells of the retina.

The choroid consists of bloodvessels connected together by loose connective-tissue, and containing large branched and pigmented cells.

It is made up of two layers, an outer and an inner. The outer part contains the larger branches of the vessels. The arteries, the short posterior ciliary, pierce the sclerotic coat close to the optic nerve, pass forwards, and bend inwards to end in the inner layer.

The veins, vasa vorticosa, are external to the arteries and join together into four or five principal trunks, which pierce the sclerotic midway between the cornea and the optic nerve

The inner coat, or tunica Ruyschiana, is formed by the

THE EYE AND ITS ATPENI'-IGES 241

capillary endings of the vessels of the outer coat ; they pass forwards to £ inch from the cornea, joining those of the ciliary processes.

The Ciliary Body consists of the ciliary processes and the ciliary muscle.

The ciliary processes are of the same structure as the rest of the choroid. They are about seventy in number, and are placed in corresponding depressions upon the surface of the vitreous humour, and upon the suspensory ligament of the lens. The bloodvessels are derived from the anterior ciliary branches.

The ciliary muscle consists of two sets of involuntary muscular fibres, radiating and circular. (Nerve supply from 3rd cranial.)

The radiating arise by tendon from the sclerotic close to the junction with the cornea, between the spaces of Fontana and the canal of Schlemm, and are inserted into the choroid opposite the ciliary processes.

The circular: a zone of circular fibres internal to the radiating, at the base of the ciliary processes.

The iris is the coloured membrane suspended in the aque- ous humour behind the cornea and in front of the lens. In the centre is an aperture, the pupil.

It is connected at its circumference to the choroid, being continuous with it ; and anterior to this it is attached to the cornea by the pillars of the iris, or ligamentum pec- tinatum.

The anterior surface is coloured and marked by wavy lines converging towards the free edge of the pupil.

The posterior surface is darkly pigmented (uvea] and marked with folds prolonged from the ciliary processes.

The framework of the iris is a delicate stroma of connec- tive-tissue, containing bloodvessels, nerves, pigment cells, and two groups of involuntary muscular fibres : —

The sphincter, a narrow band of fibres placed posteriorly close to the pupil (3rd nerve) .

The dilator, commencing at the outer margin of the iris, with the fibres converging towards the pupil (sympathetic nerve).

The bloodvessels of the iris consist of the two long ciliary and the anterior ciliary arteries ; the former pierce the sclerotic close to the optic nerve, and pass forwards in the lymph- space between the lamina fusca of the sclerotic and the lamina supra-choroidea of the choroid to enter the outer surface of the iris, having previously divided into two branches. They anastomose with the corresponding vessels of the opposite

10

242 THE POCKET ANATOMY

side, and with those from the vascular zone of the sclerotic, formed by the anterior ciliary arteries. These form the circulus iridis major. Small branches from this circle converge towards the pupil, and freely anastomose with one another, forming the circulus iridis minor.

The veins follow the same arrangement as the arteries, and communicate with the canal of Schlemm.

The nerves of the choroid and iris are about fifteen in number, and are the ciliary nerves, from the lenticular ganglion and the nasal branch of the 5th ; they follow very closely the course of the bloodvessels, and, reaching the ciliary body, form a plexus, sending twigs to the ciliary muscle, iris, and cornea.

The retina is the expanded termination of the optic nerve, and forms the innermost tunic of the eye. It reaches forwards nearly as far as the ciliary processes, where it ends in a saw- edged border, the ora serrata, and from this border there is prolonged a thin layer as far as the ciliary processes, which blends with the uvea of the iris. This prolongation contains no nerve-fibres, and is called the pars ciliaris retina.

The outer surface is covered with uveal pigment -cells (formerly described as part of the choroid).

The inner surface contains : —

The macula lutea, or yellow spot, situated in the axis of the globe.

Thefovea centralis, a depression in the preceding.

Theporus opticus, or disc, about ^ inch to the inner side of the yellow spot, where the optic nerve enters, and from which its fibres radiate ; coursing over the optic disc may be seen the central vessels of the retina.

Bloodvessels of the retina : —

The central artery of the retina passes through the optic nerve, and reaches the inner surface of the retina through the disc. It here divides into two branches, an ascending and descending, and each of these, again, into an outer or temporal division, and an inner or nasal.

The outer branches give small offsets to end in capillaries round the fovea. The rest of the branches are distributed, as capillaries, to the retina, as far as the ora serrata, but the smaller branches do not anastomose with one another or with any other vessels. The veins follow the same distribu- tion as the arteries.

The vitreous body is a soft gelatinous substance occupying about $ of the eye-ball. It supports the retina behind, and is hollowed out in front for the lens

THE EYE AND ITS APPENDAGES 243

Between the retina and the vitreous, and enclosing the latter except in front, is a thin capsule, the hyaloid membrane.

This membrane passes forwards in front to the anterior part of the margin of the lens. It becomes stronger in this part, and is called the zonule of Zinn, the zonula ciliaris, or the suspensory ligament of the lens.

The zonule commences near the ciliary processes, and passes forwards to the front of the lens, and is attached in front to the lens capsule. In addition some fibres are attached to the extreme edge of the lens, and others become continuous with the posterior part of the capsule.

The interstices between these fibres are occupied by fluid, but after death they may be distended with air, and an appearance of a canal (canal of Petit) encircling the lens is produced.

Extending forwards from the optic disc through the vitreous, as far as the capsule of the lens, is the canal of Stilling, or hyaloid canal, which is the remains of a passage for a branch from the central artery of the retina in the foetus.

The lens is a transparent bi-convex body enclosed in a transparent membrane, the lens capsule. It is in contact anteriorly with the iris ; posteriorly it rests in a depression in the vitreous body, and it is surrounded by the suspensory ligament or zonule of Zinn. It is about £ inch in diameter, and about \ inch thick.

The lens capsule is the structureless membrane enclosing the lens, thick in front near its circumference, where it is strengthened by the fibres of the zonule, but very thin posteriorly.

The aqueous humour and the aqueous chambers. — The aqueous humour occupies the space between the anterior surface of the lens capsule and the posterior surface of the cornea.

The iris divides the chamber into two parts, known as the anterior and posterior chambers.

The anterior chamber is bounded in front by the cornea, behind by the iris, and opposite the pupil by the anterior part of the lens.

The posterior chamber is the triangular interval at the cir- cumference of the lens between the ciliary processes, the iris, and the zonule of Zinn,

16— a

INDEX

ABDOMINAL aorta, 82

ring, external, 44 internal, 223 Abducens nerve, 151 Abductor indicis muscle, 40 hallucis muscle, 58 minimi digiti muscle 39

pedis muscle,

58

pollicis muscle, 39 Accessorius muscle, 58

ad sacro-lumbalem, 42 Accessory obturator nerve, 169 Acromio-clavicular articulation, 9 Acromio-thoracic artery, 74 Aditus ad antrum, 232 Adductor brevis muscle, 52

obliquus hallucis muscle, 58 longus muscle, 52 magnus muscle, 52 obliquus pollicis muscle, 39 transversus hallucis muscle,

58 . pollicis muscle,

39

Alar ligaments of the knee, 17 Ampulla, membranous, 235

of the semicircular canals,

Amygdaloid lobe of cerebellum, 124 Anastomotic artery of brachial, 76 femoral, 92 Anconeus muscle, 38 Angular artery, 67

vein, 99 Ankle-joint, 18 Annular ligament of ankle, anterior,

57

external, 57

internal, 57

of wrist, anterior,

13,35 posterior,

13,36

Annulus ovahs, 205 Anterior commissure of brain, 138 Anti-helix, 230 Anti-tragus, 230 Aorta, 79

Aorta, abdominal, 82

thoracic, 80 Aortic arch, 79

opening, 46 plexus, 180 sinus, 79 Aperture of the aorta, 46

inferior vena cava,

46

coronary Arteries, 206 Eustachian tube, 232 for the femoral artery, 53 of the larynx, 210

nares, 186, 229 oesophagus, 187 pulmonary artery, 205 veins, 206 Aponeurosis, epicranial, 21

of external oblique, 44

over femoral artery, 53

of internal oblique, 44

lumbar, 45

of the pharynx, 186

plantar, 57

of the soft palate, 183

temporal, 25

of the transversalis

muscle, 44 vertebral, 41

Appendages of the eye, 237 Appendix auriculae, 200, 204, 206

vermiformis, 190 Aqueduct of Sylvius, 126

of the vestibule, 234 Aqueous humour, 243 Arachnoid membrane of the brain, 140

of cord, 116

Arbor vitae cerebelli, 126 Arch, crural or femoral, 50 of aorta, 79 of diaphragm, 46 palmar deep, 77

superficial, 78 plantar, 97 Arciform fibres, 119 Arteria acromialis thoracica, 74

anastomotica brachialis, 76

magna, 90 angularis faciei. 67

INDEX

245

\rter., aorta abdominalis, 82

thoracica, 80 articulates inferipres, 93 superiores, 93 articularis azygos, 93 auricularis posterior, 68 auditoria, 73 axillaris, 73 basilaris, 73 brachiahs, 75 bronchiales, 81 buccalis, 70 capsularis inferior, 84 media, 83 superior, 82

carotis communis dextra, 64 sinistra, 64 externa, 65 interna, 73

carpi ulnaris anterior, 78 posterior, 78 radialis anterior, 76 posterior, 76 centralis retinae, 72 cerebelli inferior, 62

anterior, 73 superior, 73 cerebri anterior, 72 media, 72 posterior, 73 cervical is ascendens, 62 profunda, 64 choroidea cerebri, 72 ciliares anteripres, 72 posteriores, 72 circumflexa anterior, 75 externa, 91 ilii interna, 89

superficialis, 91 interna, 91 posterior, 75 coeliaca, 82 colica dextra, 84 media, 84 sinistra, 84 comes nervi ischiadici, 89

phrenici, 63 communicans cerebri anterior,

72

posterior, 72 palmaris, 79 plantaris, 96 coronaria dextra, 206

labii inferipris, 67 superioris, 67 sinistra, 207 ventriculi, 82 corporis bulbosi, 88

Arter., corporis cavernosi, 88 cremasterica, 89 crico-thyroidea, 66 cystica, 83 deferentialis, 86 dentalis anterior, 70 inferior, 70 superior, 70 diapbragmatica, 63, 82 digitales manus, 79

pedis, 96, 97 dorsales pollicis, 77 dorsalis carpi radialis, 77 ulnaris, 78 hallucis, 95 indicis, 77 lingua?, 66 pedis, 94 penis, 88 scapulae, 74 epigastrica, 89

superficialis, 90 ethmoidalis anterior, 72 posterior, 72 facialis, 66 femoralis, 90 frontalis, 72 gastricae, 87 gastro-duodenalis, 83

epiploica dextra, 83 sinistra, 83 glutea, go

haemorrboidalis inferior, 87 media, 86 superior, 85 hepatica, 82 hyoidea lingualis, 66

thyroideae, 66 hypogastrica, 86 ileo-colica, 84

lumbalis, 88 iliaca communis, 85 externa, 88 interna, 86 incisoria, 70 infra-orbitalis, 70

scapularis, 63 innoroinata, 80

intercostales anteriores, 63, 81 rami anteriores,

81

posteriores, 81 intercostalis superior, 64 interossea, 78

anterior, 78 posterior, 7-; interosseas manus, 77 pedis, 95

246

INDEX

Artei., intestinales, 84 ischiadica, 89 labialis inferior, 67 lachrymalisj 71 laryngealis inferior, 62 superior, 66 Hngualis, 66 lumbales, 85

rami anteripres, 85

posteriores, 85 malleolares, 94 mammaria, externa, 74 interna, 63 masseterica, 70 maxillaris interim, 69 mediana, 78 mediastinae, 81 rneningea media, 69 parva, 69 meningeae anteriores, 71

posteriores, 61 mesenterica inferior, 84 superior, 83 metacarpa radialis, 77 ulnaris, 78 metatarsea, 95 musculo-phrenica, 63 mylo-hyoidea, 70 nasalis, 72

lateralis, 67 septi, 70

nutntia femoris, 92 humeri, 75 tibiae, 96 obturatoria, 86 occipitalis, 67 oesophageales, 81 ophthalmic;!, 71 ovariana, 84 palatina inferior, 67 superior, 70 palmaris prpfunda, 77 palpebrahs inferior, 72 superior, 72 pancreaticae, 83 pancreatico-duodenalis, 83 perforantes femorales, 92

mam ma rise in-

ternal, 63 manus, 77

.

pencardiacae, 81 perinaei superficialis, 87 p«ronea, 96

anterior, 96

pharyngea ascendens, 68 phrenicae inferipres, 82 superiores, 63

Arter. , plantaris externa, 97

interna, 96 poplitea, 92 princeps cervicalis, 68

pollicis, 77 profunda cervicis, 64

femoris, QI

inferior, 76

superior, 75 pterygoideas, 70 pterygo-palatina, 70 pudenda externa, 91

interna, 87 pulmonalis, 214

dextra, 215 sinistra, 215 pylori ca, 83 radialis, 76

mdicis, 77 ranina, 66 recurrens interossea posterior,

radialis, 76 tibialis, 97 ulnaris anterior, 78 posterior, 7! renales, 84 sacra-media, 85

lateralis, 88

scapularis posterior, 63 sciatica, 89 sigmoidea, 85 spermatica, 84 spheno-palatina, 70 spinales posteriores, 6i spinalis anterior, 62 splenica, 83 sterno-mastoidea, 66 stylo-mastoidea, 68 subclavia dextra, 59 sinistra, 59 sublingualis, 66 submentalis, 67 subscapularis, 74 superficialis cervicalis, 63 perinaei, 88 vola^, 76 supra-orbitalis, 72

scapularis, 62 tarsea, 94

temporales profundae, 69 temporalis, anterior, 69 deep, 70 media, 69 posterior, 69 superficialis, 68 thoracica acromialis, 74 alaris, 74

INDEX

247

After., thoracica longa, 74

superior, 74 tbyroidea ima, 80

inferior, 62 superior, 66 tibialis antica, 93 postica, 94 tonsillaris, 67 transversalis colii, 63 facie i, 69 perina-i, 87 pontis, 73 tympanica, 69, 71 ulnaris, 77 uterina, 86 vaginalis, 86 vertebralis, 61 vesicalis inferior, 86 media, 86 superior, 86 vidiana, 70 Articular popliteal arteries, 93

nerves, 173, 174

Articulation, acromio-clavicular, 9 astragalo-scaphoid, 19 atlo-axoid, 3 of bones of the tym- panum, 231

calcaneo-astragaloid, 19 cuboid, 19

scaphoid, 19 of carpal bones, 12 carpo-metacarpal, 13 of cervical vertebra, 2 chondro-costal, 6 sternal, 5

of coccygeal bones, 8 coraco-clavicular, 9 of costal cartilages, 6 costo-clavicular, 9 vertebral, 5 crico-aryteiT'id, 208

thyroid, 209 of cuneiform bones, 19 cuneiform to cuboid, 19 to scaphoid,

of dorsal vertebrae, 3 femoro-tibial or knee, 15 humero - cubital or

elbow, 10

ilio-femoral or hip, 14 of lower jaw, 4 of lumbar vertebrae, 2 of the metacarpal bones,

metacarpo - phalangeal, 14

Articulation, metatarsal, 20

metatarso - phalangeal,

20

occipito-atlpid, 3 axial, 4 os calcis to cuboid, 19

to scaphoid, 19 peroneo-tibial, 17 phalangeal of fingers, 14

of toes, 21

of pubic symphysis, 8 radio-carpal or wrist, 12 cubital inferior, n superior, 1 1 sacro-coccygeal, 8 iliac, 7 vertebral, 6 scaphoid to cuboid, 19 to cuneiform,

T9

scapulo-humeral, 10 sterno-clavicular, 8 tarso- metatarsal, 20 temporo-maxillary, 4 of the thumb, 13 tibio-tarsal or ankle, 18 of vertebrae, 2

Arcus externus diaphragmatis, 46 internus diaphragmatis, 46 Aryteno-epiglottidean folds, 209 Arytenoid cartilages, 208

muscle, 31 Ascending cervical artery, 62

vein, 10 1 colon, 190

pharyngeal artery, 68 vein, 10*

Attollens aurem muscle, 22 Attrahens aurem muscle, 22 Auditory artery, 73

nerve, 153, 236 nucleus, 123 Auricle of the ear, 230 Auricles of the heart, 204

left, 206 right, 204

Auricular artery, posterior, 68 nerve of vagus, 155 nerves, great, 160

inferior, 147 superior, 147 posterior, 152 vein, loo Auriculo-temporal nerve, 147

ventricular aperture, left,

206

ventricular aperture, right, 205

248

INDEX

Auricularis magnus nerve, 160 Axillary artery, 73 fascia, 32 vein, 102

Axis, coeliac, of artery, 8a of cochlea, 235 thyroid, 62 Azygos, artery, 93 veins, 104 uvulae muscle, 30

Base of brain, 129 Basilar artery, 73

membrane, 237 Basilic vein, 102 Biceps femoris muscle, 54

flexor cubiti muscle, 35 Bicuspid teeth, 181 Bile ducts, 193 Biventral lobe, 125 Bladder, 218

interior of, 219 connections of, 219 ligaments of, 48, 191 Bones of the ear, 232 Brachial aponeurosis, 35 artery, 75 plexus, i6x veins, 102

Brachialis anticus muscle, 35 Brain, base of, 129

membranes of, 139 Broad uterine ligament, 227 Bronchial arteries, 81 glands, 113 veins, 105 Bronchus, left, 212

right, 212

Brunner's glands, 190 Buccal artery, 70 nerve, 146

Buccinator muscle, 24 Bulb of the urethra, 221

artery of, 88 Bulbus olfactorius, 141

Caecum coli, 190

connections of, 190 Calamus scriptorius, 120 Calices of the kidney, 217 Calciform papillae, 217 Canal, Hunter's, 53

of cochlea, 236

of Petit, 243

of spinal cord, 116

of Stilling, 243

of the tensor tympani, 232 Canine teeth, 181

Capsular arteries, inferior, 84 middle, 83 superior, 8 a ligament of the hip, 14 knee, 16 shoulder, 10 thumb, 13 Capsule of crystalline lens, 243 of Glisson. 194 suprarenal, 217 Caput gallinaginis, 221 Cardiac nerve, inferior, 178 middle, 178 of pneumogastric, 156 superior, 176 plexus, 179 veins, 106 Carneae columnse, 199 Carotid artery, external, 65 internal, 73 left common, 64 right common, 64

Carpal artery, radial anterior, 76 posterior, 76 ulnar anterior, 78 posterior, 78 Carpo-metacarpal articulation, 13 Cartilage, arytenoid, 208 cricoid, 208 cuneiform, 209 of the ear, 230 thyroid, 207 triangular of the nose,

228

Cartilages of the nose, 228 of Santorini, 208 of trachea, 211 Caruncula lachrymalis, 237 Carunculae myrtiformes, 225 Cauda equina, 1 14 Cava inferior, 105 superior, 103 Cavernous body, 221

artery of, 88 plexus, 177 sinus, 98

Central artery of the retina, 73 passage of cochlea, 235 lobe of brain, 133 Centrum ovale cerebri, 134 Cephalic vein, 102 Cerebellar arteries, inferior, 62 superior, 73

Cerebellum, form of, 124 lobes of, 12 4 structure of, 125 Cerebral artery, anterior, 72

INDEX

249

Cerebral artery, middle, 72

posterior, 73

Cerebrum, division into lobes, 131 form of, 130 interior, 134 structure, 138 <"'Tvical fascia, 26

ganglion, inferior, 178 middle, 177 superior, 176 glands, in nerves, anterior branches,

159 posterior branches,

159

plexus of nerves, 159 plexus of nerves, deep

branches, 161 plexus of nerves, superficial,

160

Cervical is, ascendens artery, 62 muscle, 42 . vein, 101 profunda artery, 64 vein, 101

superficialis nerve, 160 Cervico-facial nerve, 153 Cervix uteri, 226 Chamber of the eye, anterior, 243 posterior, 2(3 Check ligaments, 4 Chiasma of the optic nerves, 129 Chondro-costal articulations, 6 sternal articulations, 5 Chorda tympani nerve, 152 Chordae tendineae, 205 Chordae vocales, 210 Chorda: Willisii, 98 Choroid arteries of the brain, 72 coat of the eye, 240 plexuses of the brain, 137 veins of the eye; 240 brain, 97

Ciliary arteries, 72 muscle, 241

processes of the choroid, 241 nerves of nasal, 143

of lenticular ganglion,

Circle of Willis, 7^ Circular sinus, 98 Circumflex artery, anterior, 75 external, 91 internal, 91 posterior, 75 iliac artery, deep, 89

superficial, 91 e, 162

Clavicular cutaneous nerves, 160 Clitoris, 225 Coccygeal muscle, 49 nerve, 170

Cochlea, canal of, 236 nerves of, 237 Coeliac artery, 82

plexus, 1 80 Colic artery, left, 84

middle, 84 right, 84 veins, 108 Colon, 190, ic i Columnar carneae, 205 Columns of the cord, 115 Comes nervi ischiadici artery, 89

phrenici artery, 63 Commissure, anterior, 138

of the cerebellum, 125 of the cord, 116 great, 135

of the optic nerves, 129 posterior, 128 soft, 128 Commissural fibres of the medulla,

119 Communicating artery of anterior

cerebral, 72 Communicating artery of posterior

cerebral, 72 Communicating artery in the palm,

Communicating peroneal nerve, 175 Compressor muscle of the nose, 23

of the urethra, 49 Concha, 230 Conjoined tendon, 44 Conjunctiva, 238 Conoid ligament, 9 Constrictor muscle, inferior, 29 . middle, 29

superior, 29 Conus arteriosus, 205 medullaris, 114 Convolutions of the brain, 131

of hemisphere, 131

of longitudinal fissure,

132 Coraco-brachialis muscle, 34

clavicular articulation, 9 humeral ligament, 9 Cornea, 240 Cornicula laryngis, 210 Cornua of gray crescent, 116

of lateral ventricles, 135 Corona glandis, 221 Coronary vessels of the heart, 206 of the lips, 67

250

INDEX

Coronary artery of the stomach,

82

ligament of the liver, 192 plexus of the stomach,

1 80

plexus of the heart, 1 80 sinus, 106

Corpora albicantia, 129 Arantii, 205 cavernosa, 221 geniculata, 128 olivaria, 120 quadrigemina, 127 restiformia, 119 striata, 137 Corpus callosum, 134

dentatum cerebelli, 126 fimbriatum uteri, 227 geniculatum externum, 128 internum, 128 Highraori, 223 olivare, 120

spongiosum urethrae, 221 thyroideum, 215 Corrugator supercilii muscle, 22 Costo-clavicular ligament, 9 coracoid membrane, 32 transverse ligaments. 5 Cotunnius, nerve of, 145 Cotyloid ligament, 15 ( 'overed band of Reil, 135 Cowper's glands, 220 Cremaster muscle, 44 Cremasteric artery, 89 fascia, 222

Cribriform fascia, 50 Crico-arytenoid artirulation, 208

muscle, lateral, 31

posterior, 31 thyroid articulation, 208 membrane, 209 muscle, 30

Cricoid cartilage, 209 Crista vestibuli, 236 Crucial ligaments, 16 Crura cerebelli, 125 cerebri, 126 of the diaphragm, 46 of the fornix, 136, 1 37 Crural arch, 50

deep, 51 canal, 50 nerve, 169 ring, 50 sheath, 50 Cystic artery, 83 duct, 194 plexus of nerves, 180

Decussation of the pyramids, i»o Deep cervical artery, 64

crural arch, 51

transverse muscle of perinaeun^

49

Deferential artery, 36 Deltoid ligament, 18

muscle, 33

Dental artery, anterior, 70 inferior, 70 superior, 70

Dental nerve, superior, 144, 145 inferior, 147 posterior, 144 Dentate ligament, 117 Depressor anguh oris muscle, 24

labii inferioris muscle, 24 alee nasi muscle, 23 Descendens hypoglossi nerve, 158 Descending colon, 191 Diaphragm, 46

arteries, 62, 83 plexus of, 1 80 Digastric muscle, 28 nerve, 152

Digital arteries of plantar, 97 of radial, 77 of ulnar, 79 nerves of median, 164 of plantar, 174 of radial, 165 of ulnar, 164 Dilatator muscle of the n 'f,e, 24

of the pupil, 241 Dorsal artery of the foot, 94 of the penis, 88 of the scapula, 74 of the tongue, 66 nerves, anterior branches,

*59

posterior branches, 158 cutaneous of the hand,

164

of the penis, 172 Dorsi-spinal veins, 105 Douglas's fold, 45 Ductus ad nasum, 239 arteriosus, 214 communis choledochus, 194 cysticus, 194 ejacularorius, 224 hepaticus, 194 lymphaticus, in pancreaticus, 195 reunions, 236 Riviniani, 185 Stensonis, 184 thoracicus. no

INDEX

251

Ductus Whartonii, 185 Duodenum, connections, 188 Dura mater, 139

of the cord, 116

Ear, external, 230 internal, 234 Eighth nerve, 153 Ejaculator urinae muscle, 49 Elbow joint, 10 Eminentia collaterals, 136 Encephalon, 117 Endocardium, 205 Endolymph, 234 Epididymis, 223 Epigastric artery, 89

superficial, 90 veins, 109 Epiglottis, 210 Erector clitoridis muscle, 49 penis muscle, 49 spinae muscle, 42 Ethmoidal arteries, 72 Eustachian tube, cartilaginous part,

232

osseous part, 232 valve, 204 Extensor carpi radialis brevior

muscle, 37

Extensor carpi radialis longior muscle, 37

carpi ulnaris muscle, 38 digiti minimi muscle, 37 Extensor digitorum brevis muscle, 57 communis

muscle, 37 1 o n gu s pedis

muscle, 55 indicis muscle, 38 ossis metacarpi muscle, -;8 proprius hallucis muscle^ 5. brevis pollicis muscle, 38 longus pollicis muscle, 38 External cutaneous nerves of arm

163

of thigh, i6,c saphenous nerve, 173

vein, 108 Eye-ball, 239 brows, 237 lashes, 237 lids, 237

muscles of, n structure, 237

Facial artery, 66 nerve, 151 vein, 99

Falciform ligament of the liver, 192 border of saphenous open ing, 50

Fallopian tube, 227 Falx cerebelli, 140

cerebri, 139 Fascia, axillary, 32

brachial, 35

cervical, deep, 26

costo-coracoid, 32

cremasteric, 222

cribriform, 501

of Colles, 47

of the forearm, 35

iliac, 50

intermuscular of the humerus,

of the thigh, 49 lata, 49 lumborum, 45 masseteric, 25 obturator, 47 of the leg, 56 of the pyriformis, 48

perinaeal, deep, 47

superficial, 47 plantar, deep, 57 recto-vesical, 48 temporal, 25 transversalis, 222 triangularis, 44 Fasciculus teres, 121 Femoral artery, 90

vein, 109

Femoro-tibial articulation, 15 Fenestra ovalis, 231

rotunda, 232 Fibres of the cerebrum, 138

of the cerebellum, 1 24 Fifth nerve, 142

ventricle of brain, 136 Filiform papillae, 182 Fillet of the olivary body, 120 Filum terminate, 114 First nerve, 141 Fissure, longitudinal, 130

paneto-occipital, 130 of Rolando, 130 of Sylvius, 130 transverse, 130 Fissures of Santorini, 231 of the cord, 115 of the cerebrum , 130 Flexor accessorius muscle, 58

brevis minimi digiti muscle, ^9 pedis muscle,

carpi radialis muscle, 36 ulnaris muscle, 36 digitorum brevis pedis muscle,

58

longus pedis muscle, 56

252

INDEX

Flexor digitorumprofundusmuscle,36 sublimis muscle, 36 hallucis longus muscle, 56 brevis muscle, 58 pollicis longus muscle, 37 brevis muscle, 39 Flocculus cerebelli, 124 Fold of Douglas, 45 Follicles, Meibomian, 238 Foramen of Monro, 137

for inferior vena cava, 46 of Winslow, 201 ovale, 206

Foramina Thebesii, 204 Fornix, 136 Fossa navicular of the urethra, 221

of the pudendum, 225 ovalis, 205

Fossae of abdominal wall, 198 Fourth nerve, 142

ventricle, 120 Fovea centralis, 242

hemispherica, 234 hemi-elliptica, 234 Foveae of fourth ventricle, 121 Fraenum linguae, 18 c

praeputii, 221 Frontal artery, 72 lobe, 131 nerve, 143 vein, 98

Fungiform papillae, 181 Funiculus cuneatus, 119 gracilts, 119 of Rolando, 119

Galen, veins of, 97, 137 Gall bladder, 193 Ganglia, cervical, inferior, 178 middle, 177 superior, 176 lumbar, 178 of spinal nerves, 158 sacral, 178 semilunar, 179 thoracic, 178

Ganglion of the vagus, 155 Gasserian, 142 impar, 179 jugular, 154 lenticular, 143 Meckel's, 145 ophthalmic, 150 otic, 148 petrosal, 154 spheno-palatine, 145 submaxillary, 148 Gastric arteries, 83

Gastric plexus, 180

vein, 107

Gastro-colic omentum, 199 epiploic arteries, 83

vein, 108

hepatic omentum, 199 Gastrocnemius muscle, 55 Gemellus inferior muscle, 54 superior muscle, 54 Geniculate bodies, 128 Genio-hyo-glossus muscle, 29

hyoid muscle, 29 Genital organs, 220 Genito-crural nerve, 168 Gimbernat's ligament, 44 Gland, lachrymal, 238 parotid, 183 pineal, 129 pituitary, 129 prostate, 220 sublingual, 185 submaxillary, 184 Glands, axillary. 112

Bartholm's, 225 bronchial, 113 Brunner's, 190 cardiac, 113 cervical, in concatenate, in Cowper's, 220 inguinal, 113 intercostal, 113 intestinal, 112 lingual, 182 lumbar, 112 mediastinal, 113 Meibomian, 237 mesenteric, 112 oesophageal, 113 of Pacchioni, 139 pelvic, 112 Peyer's, 190 popliteal, 113 sternal, 113 Glans of the clitoris, 225

of the penis, 220 Glenoid ligament, 10 Glisson's capsule, 194 Globus major epididymis, 2*3 minor epididymis, 223 Glosso-pharyngeal nerve, 153

nucleus, 122 Glottis, 210 Gluteal artery, 90

nerve, superior, 171 nerves, inferior, 171 Glutens maximus muscle, 53 medius muscle, 53

INDEX

Glutens minimus muscle, 53

Gracilis muscle, 52 Grey commissure of llie cord, 116 crescent of the cord, 1 15 substance of the corpus stria -

turn, 137 substance of the medulla ob-

longata, 123 substance of the third ventricle,

128

tubercle of Rolando, 119 Great omentum, 199 Gustatory nerve, 147 Gyrus fornicatus, 134

Hittnorrhoidal artery, inferior, 87 middle, 86 superior, 85 nerve, inferior, 172 plexus, 180 veins, 109

Hamulus laminae spiralis, 235 Heart, 202 Helicotrema, 235 Helix,_230 Hepatic artery, 82 duct, 194 plexus, 180 veins, 106 Hip-joint, 14 Hippocampus major, 136 minor, 136 Hunter's canal, 53 Hyaloid membrane, 243 Hymen, 225 Hyo-glossus muscle, 29 Hypogastric artery, 86

plexus of nerves, 180 Hypoglossal nerve, 157 nucleus, 13*

Ileo-caecal valve, 190 Ileo-colic artery, 84 lleum, 189

Iliac artery, common, 85 external, 88 internal, 86 colon, 191 fascia, 50

vein, common, no external, 109 internal, 109 Iliacus muscle, 51 Ilio-costalis muscle, 42 Ilio-femoral articulation, 15 hypogastric nerve, 168 inguinal nerve, 168 lumbar artery, 88

Incisor branch of nerve, 147

teeth, 181 Incus, 233 Inferior cornu of the lateral ventricle,

i3S

maxillary nerve, 148 Infra-orbital artery, 70

nerves, 144, 153 vein, 99

scapular artery, 03 spinatus muscle, 34 trochlear nerve, 143 Infundibulum of the brain, 129 Inguinal canal, 223 glands, 113 Innominate artery, 80 veins, 103

Interarticular cartilage of the jaw, 4 of the hip, 14 of the knee, 15 of the ribs, 5 of the scapula, 9 sacro-iliac, 7 sterno-clavicular, 8 of the symphysis, 8 of the vertebrae, 2 of the wrist, 12 Interclavicular ligament, 8 Intel-columnar fascia, 44 [81

Intercostal arteries, anterior branches, posterior branches, artery, superior, 64 [81 muscle, external, 45 internal, 46 nerves, 166

cutaneous anterior, 1 66 lateral, 166 veins, superior, 104 Intercosto-humeral nerve, 166 Intermuscular septa of the arm, 34 of the foot, 57 of the thigh, 50 Internal cutaneous nerve of the arm,

163 of the thigh.

169 sapbenous nerve, 170

vein, 108

Interosseous arteries of the foot, 95 of the hand, 77 artery, anterior, 78 posterior, 78 ligament of the arm, n of the leg, 17 muscles of the foot, 59

of the hand, 40 nerve, anterior, 164 posterior, 165

254

INDEX

Interspinal muscles, 43 Intertransverse muscles, 43 Intervertebral substances, 2 Intestinal arteries, 84 Intestine, large, 190 small, 1 83 Iris, 241

nerves of, 242

structure of, 241

vessels of, 241 Island of Reil, 133 Isthmus of the thyroid body, 215 Iter a tertio ad quartum ventriculum, 126

Jacobson's nerve, 154 Jejunum, 189 Joint, ankle, 18 elbow, 10 hip, 14 knee, 15 lower jaw, 4 shoulder, 10 thumb, 13 wrist, 12 Jugular ganglion, 154

vein, anterior, 100 external, 100 internal, 101

Kidney, 2x6

connections of, 216 Knee of the corpus callosum, 135 joint, 15

Labia pudendi externa, 225 interna, 235

Labial artery, inferior, 67 Labyrinth, 234

membranous, 235

osseous, 234 Lachrymal artery, 71

canals, 238

duct, 238

gland, 238

nerve, 143

sac, 238

Lacunae of the urethra, aaa Lamina cinerea, 129

spiralis cochlea;, 235 Laminae of cerebellum, 124 Large intestine, connections, 190 Laryngeal arteries, 62, 66

nerve, external, 156 inferior, 156 superior, 156

pouch, ?TO Larynx, 207

Larynx, aperture of, 209 cartilages of 207 interior of, 210 ligaments, 209 muscles, 30 nerves, 156] ventricle, 210 vessels, 62, 66 Lateral column of the medulla, 119

of the cord, 115 sinus, 98 ventricles, 135 Latissimus dorsi muscle, 40 Lens, 243

Lenticular ganglion, 143 Levator anguli oris muscle, 24

scapulae muscle, 41 ani muscle, 49 labii superioris muscle, 24

alaeque nasi, muscle, 23 inferioris muscle, 24 palati muscle, 30 palpcbras superioris muscle,

22

Levatores costarum muscle, 46 Ligament of the lung, 212 Ligaments of the bladder, 48, 197 of the larynx, 209 of the ovary, 227 of the uterus, 227 Ligament, acromio clavicular, 9 alar of the knee, 17 annular, anterior of the

ankle, 57 external of the

ankle, 57 anterior of the

Wris-t>I3r v posterior of the

wrist, 13 anterior of ankle, 18

of elbow-joint, 10 of knee-join*, 16 of wrist -joint, *a of carpus, 13 astragalp-scaphoid, 19 atlo-axoid, anterior, 3 posterior, j

transverse, 3 calcaneo-astragaloid, 19 cuboid, 19 scaphoid, 19 capsular of the hip, 14 of the knee, 16 of the shoulder, to of the thumb, 13 carpal, dorsal, 12

INDEX

255

Ligament, carpal, palmar, 12 carpo-metacarpal, 13 check, 4

common, anterior of ver- tebrae, 2

common, posterior, 2 conoid, 9

coraco-acromial, 9 clavicular, 9 humeral, 10 coronary, 17 costo-clavicular, 9 coracoid, 32 transverse, anterior, 5 middle, 5 posterior 5 vertebral, 5 cotyloid, 15 crico-thyroid, 209 crucial, 16 deltoid, 18

dorsal of the carpus, 12 of Gimbernat, 44 plenoid, 10 ilio-femoral, 15 lumbar, 6

interartieular of the cla- vicle, 9 of the hip, 15 of the jaw, 4 of the knee, 16 of the pubes, 8 of the ribs, 5 interclavicular, 8 interosseous of astragalus

and os calcis, 19 of carpus, 13 of cuneiform bones, 19 of metacarpal bones,

13

of metatarsal bones, 20 of radius and ulna, n of the scaphoid and

cuboid, 19 of the tibia and fibula,

17 inferior, of the tibia and

fibula, 18 interspinous, 2 intertransverse, 3 intervertebral, 2 ischio-capsular, 15 lateral, external of the

ankle, 18 internal of the

ankle, 18

external of the carpui, 13

Ligament, lateral, internal of the

carpus, 13 external of the

elbow, ii internal of the

elbow, ii pnalangeal of the

foot, 20 phalangeal of the

hand, 14 external of the

jaw, 4 internal of the

jaw, 4 external of the

knee, 16 internal of the

knee, 16 external of th*;

wrist, 12 internal of the

wrist, 12 long plantar, 19 lumbo-sacral, 6 metacarpal, dorsal, 13

palmar, 13

metacarpo-phalangeal, 14 metatarsal, dorsal, 20

plantar, 30 mucous, 17 obturator, 8

occipito-atloid, anterior, 3 lateral, 4 posterior, 4 occipito-axoid, 4 odontoid, 4

orbicular of the radius, ii of the patella, 15 peroneo-tibial, 17 of Poupart, 44 posterior of carpus, 13 of elbow, ii of knee, 15 of scapula, 9 of wrist, 12

proper of the scapula, 9 pubic, anterior, 8 posterior, 8 superior, 8 pubp- femoral, 15 radio-ulnar, ii rhomboid, 9 round of the hip, 15 round of the radius and

ulna, ii sacro-coccygeal, anterior, 8

posterior, sacro-iliac, anterior, 7

256

INDEX

Ligament, sacro-iliac, posterior, 7 sacro-sciatic, great, 7 small, 7

sacro-vertebral, 6 of the scapula, transverse, 9 sternal, anterior, 6 posterior, 6 sterno-clavicular, 8 stylo-hyoid, 5

maxillary, 4 sub-pubic, 8 supraspinous, 2 suspensory of penis, 220 tarso-metatarsal, dorsal, 20 plantar, 20 thyro-arytenoid, 209

epiglottidean, 210 hyoid, 209 tibio-fibular, 17 transverse of the atlas, 3

of the fingers,

of the hip, 15 of the knee, 17 of metacarpus, 14 of metatarsus, 20 of scapula, 9 trapezoid, 9 Ligament, triangular of the urethra,

of Winslow, posterior, 15 Ligamenta alaria, 17

subflava, 2 Ligamentum arcuatum, 46

denticulatum, 116 arteriosum, 215 latum pulmonis, 214 longum plantae, 19 mucosum, 17 nuchse, 2 patellae, 15

posticum Winslowii, 15 spirale, 236 subflavum, a teres, 15 Limbus, 236 Linea alba, 44 Linear transversae, 45 Lingual artery, 66 glands, in nerve, 147, 154 vein, 101

Linguales muscles, 182 Liquor Cotunnii, 234 Liver, 192

connections of, 192 ligaments, 192 vessels, 194

Lobes of the cerebellum, 1 24 of the cerebrum, 131 of the testis, 223 of the liver, 193 Lobus auris, 230

caudatus, 193 quadratus, 193 Spigelii, 193 Locus niger, 126

perforatus anticus, 129 posticus. 120

Longissimus dorsi muscle, 42 Longitudinal fibres of the brain, 135 fissure of the liver, 193 sinus, inferior, 98 superior, 97 Longus colli muscle, 31 Lumbar aponeurosis, 45 arteries, 85

anterior branches,

85 posterior branches,

85

ganglia, 178 glands, 112 nerves, anterior branches,

167 posterior branches,

167

plexus, 167 veins, 105

Lumbo-sacral nerve, 167 Lumbricales muscles of the foot, 56

of the hand, 39 Lungs, 212

connections, 213 Lymphatic duct, right, in Lymphatics of the arm, 112 of the axilla, na of the groin, 113 of the lungs, 113 of the mesentery, 112 of the neck, in of the pelvis, 112 of the popliteal space,

113

of the thorax, 113 Lyra, 137

Malleolar arteries, 94 Malleus, 232

muscles of, 233

Mammary artery, internal, 63 Masseter muscle. 25 Masseteric artery, 70 nerve, 146

Maxillary artery, internal, 69 nerve, inferior. 146.

INDEX

257

Ma .illary nerve, superior, 144

vein, internal, 100 Meatus auditorius ex t emus, 230

urinarius, 221, 225 Meatuses of the nose, 228 Meckel's ganglion, 145 Median basilic vein, 102 cephalic vein, ioa nerve, 163 vein, IDS

Mediastinal arteries, 81 Mediastinum of thorax, 201

of testis, 223 Medulla oblongata, 118

grey matter, 122

structure of, 118

Medullary subiiance of the kidney,

217

Medullary velum, inferior, 125 superior, 122 Meibomian follicles, 238 Membrana basilaris, 237 sacciformis, 12 tympani, 233 Membrane, hyaloid, 243

of the labyrinth, 235 obturator, 8 of Reissner, 236 Membranes of the brain, 139

of spinal cord, 116 Membranous labyrinth, 235

part of the cochlea,

236

part of the urethra, 221 Meningeal artery, anterior, 71 middle, 69 posterior, 61 small, 69

Mesenteric artery, inferior, 84 superior, 83 glands, ii2 plexus, inferior, 180 superior, 180 vein, inferior, 107 superior, 107 Meso-caecum. 200

colon, pelvic, 194

transverse, 200 Metacarpal arteries, 77, 78 Metatarsal artery, 95 Mitral valve, 206 Modiolus of the cochlea, 235 Molar teeth, 181 Mons Veneris, 295 Motor oculi nerve, 142 Mucous ligament, 17 Multifidus spinae muscle, 43 Musculi papillares, 205

Musculi pectinati, 205 Muscnlo-cutaneous nerve of the arm,

163

phrenic artery, 63

spiral nerve, 165

Muse., abductor digiti minimi, 39

digi ti minimi

pedis, 58 hallucis, 58 indicis, 40 pollicis, 39 accessorius pedis, 58 accessorius ad sacro-lumba-

lem, 42 adductor breyis, 52

obliquus hallucis,

longus, 52 magnus, 52 obliquus pollicis,

39

transver- sus, 39

transversus hallu- cis, 58

anconeus, 38

arytenoideus, 31

attollens aurem, 22

attrahens aurem, 22

azygos uvulae, 30

biceps fempris, 54 cubiti, 35

biventer cervicis, 43

brachialis anticus, 35

buccinator, 24

cervicalis ascendens, 41

ciliaris, 241

coccygeus, 49

complexus, 43

compressor naris, 23

constrictor, inferior, 29 medius, 29 superior, 29

coraco-brachialis, 34

oorrugator supercilii, 22

cremastericus, 44

cricu - arytenoideus latera- l's, 3i

crico - arytenoideus posti- cus, 31

crico-thyroideus, 30

cnireus, 52

deltoideus, 33

depressor anguli oris, 24

depressor labii infenoris,

alas nasi, 23 diaphragma, 46

INDEX

Muse., digastricus, 28 dilatator naris, 24	vlusc. , infra-spinatus, 34 intercostales extcrm, 4\,
pupillae, 241	interni, 46
ejaculator urinse, 49	interossei manus dorsales,
erector clitoridis, 49	40
penis, 49	interossei manus palmares,
spinae, 42	4°
extensor carpi radialis	interossei pedis dorsales, 59
brevior, 37 carpi radialis	interossei pedis plantares, 59 inter-spmales, 43
longior, 37	inter-transversales, 43
carpi ulnaris, 38 digitorum brevis	latissimus dorsi, 40 levator anguli oris, 24
pedis, 57	scapula:, 41
digitorum corn-	ani, 49
munis, 37	labii superioris, 24
digitorum longus	labii superioris alas-
pedis, 55	que nasi, 23
indicis, 38 minimi digiti, 37 ossis metacarpi pol-	palati, 30 paipebrffi superioris, 22
licis, 38	levatores costarum, 46
proprius hallucis, 55	linguales, 182
brevis pollicis,	longissimus dorsi, 42
38	longus colli, 31
longus pollicis,	lumbricales manus, 39
38	pedis, 58
flexor accessorius, 58	massetericus, 25
brevis digiti minimi,	multindus spinae, 43
39 brevis digiti minimi	mylo-hyoideus, 28 obliquus abdominis exter-
pedis, 59	nus, 44
brevis hallucis, 58	obliquus abdominus inter-
brevis pollicis, 39	nus, 44
carpi radialis, 36	obliquus capitis inferior, 32
ulnaris, 36	superior, 32
digitorum brevis	oculi inferior, 23
pedis, 58	superior, 23
digitorum longus	obturator externus, 54
pedis, 56	internus, 54
digitorum profundus,	occipi to-frontal is, 21
36	omo-hyoideus, 28
digitorum sublimis,	opponens minimi digiti, 39
hallucis longus, 56	pollicis, 39 orbicularis oris, 24
pollicis longus, 37	palpebrarum, 23
pastrocnemius, 55 gemellus inferior, 54	palato-glossus, 30 pharyngeus, 30
superior, 54	palmaris brevis, 39
genio-hyo-glossus, 29	longus, 36
hyoideus, 29	pectin eus, 52
gluteus maximus, 53	pectoralis major, 33
medius, 53	minor, 33
minimus, 53	peroneus brevis, 56
gracilis, 52 hyo-glossus, 29	longus, 56 tertius, 55
ihacus, 51	plantaris, 55
ilio-costalis, 4.*	platysma myoides, 26

INDEX

25$

Muse., popliteus, 56 pronator, quadratus, 37	Muse., sterno-thyroideus, 28 stylo-glossus, 29
radii teres, 36	hyoideus, 28
psoas ma gnus, 51 parvus, 51	pharyngeus, 30 subanconeus, 35
pterygoideus externus, 25 internus, 25	subclavius, 33 subcostales, 46
pyramidal is abdominis, 45 nasi, 23	subcrureus, 52 subscapularis, 34
pyriformis, 53	supinator brevis, 38
quadratus femoris, 54	longus, 37
luiuborum, 45	supra-spinatus, 34
quadriceps extensor, 51 rectus. abdominis, 45	temporalis, 25 tensor palati, 30
capitis anticus major,	tarsi, 22
3i capitis anticus minor,	tympani, 233 fasciae femoris, 51
3*	terei major, 34
lateralis, 31	minor, 34
posticus major,	thyro-arytenoideus, 30
3a. posticus minor,	hyoideus, 28 tibialis anticus, 55
32	posticus, 56
femoris, 52	trachelo-mastoideus, 42
oculi externus, 23	transversalis abdominis,
inferior, 23	44
internus, 23	coin, 42
superior, 23	transversus perinan, 49
retraheus aurem, 22	trapezius, 40
rhomboideus major, 41	triangularis sterni, 46
minor, 41	triceps extensor, 35
ri«orius, 25	vastus externus, 51
roiatores dorsi, 43	internus, 52
salpingo-pliaryngeus, 30	zygomaticus major, 24
sartonus, 51	minor, 24
scalenus anticus, 31	Mylo-hyoid artery, 70
medius, 31	muscle, 28
posticus, 32	nerve, 147
«emi-membranosus, 54
spinalis colli, 43	Nares, 229
dorsi, 43 tendinosus, 54	Nasal artery, 72 lateral, 67
serratus magnus, 33 posticus inferior, 41	cartilages, 228 duct, 238
superior, 4 1	fossae, 228
soleus, 55	nerve, 143
sphincter am externus, 48	Naso-palatine artery, 70
internus, 48	nerve, 145
pupillae, 241	Nerve of Jacobson, 154
vaginae, 49 spinalis dorsi, 42 splenius capitis, 41	of Wrisberg, 163 Nerve to the inferior gemellus and quadratus, 171
colli, 42	latissimus, 163
stapedius. 234 sterno - cleido - mastoideus,	levator anguli scapulae, 162
•6 hyoideus, s%	longus colli, 162 obturator internus, 171
17—2

260

INDEX

Nerve to the pectineus, 169

pterygoid, internal, 146 pyriformis, 171 rhomboid muscles, 162 scaleni, 162 serratus magnus, 163 subclavius, 162 superior gemellus, 171 tensor palati, 148

tympani, 148 fasciae femoris,

172

teres major, 103 minor, 163 vastus externus, 170 interims, 170

Nervous tunic of eyeball, 242 Nerv., abducens, 151

accessories obturator! us, 169

spinalis, 157 acromiales cutanei, 160 articularis poplitei, 173 articularis obturatorius, 169 auditorius, 153 auricularis inferior, 147 magnus, 160 pneumogastrici, 1 55 posterior, 152 auriculo-temporalis, 147 buccales, 146, 152 buccinatorius, 152 cardiacus inferior, 178 medius, 178 pneumogastrici, 156 superior, 176 cervicales nervi facialis, 153

rami anteriores, 1 59 posteriores, 1 59 cervicalis superficialis, 160 cervico-facialis, 153 chorda tympani, 152 ciliaris ganglii ophthalmici,

»43.

nasal is, 143 circumilexus, 162 claviculares cutanei, 160 coccygealis, 170 cochlearis, 237 communicans fibularis, 175

tibialis, 173 cruralis, 169 cutanei abdominis anteriores,

167 abdominis laterales,

167

Cutaneus dorsalis mauds, 164 externus brachialis, 163

Nerv., cutaneus externus lumbalis,

168 externus musculo-

spiralis, 165 infra-maxillar., 153 interims brachialis

major, 163 internus brachialis

minor, 163 internus femoris, 169 internus muv.ulo-

spiralis, 165 medius femoris, 169 muse. -cutanei, 163 palmaris, 164 plan tar is, 174 radialis, 165 supra-maxillar., 153 dentales posteriores, 144 dentalis, superior, 144, 145

inferior, 147

descendens hypoglossi, 158 diaphragmaticus, 160, 180 >ligastricus, 152 digitales median!, 164 plantares, 170 radiales, 164 ulnares, 164

dorsales, rami ante: lores, 166 posteriores, 166 dorsalis penis, 172

ulnaris, 164 facialis, 151 frontalis, 143 genito-cruralis, 168

ramus fempralis, 168 ramus genitalis, 168 glosso-pharyngeus, 153 glutei mfenores, 171 gluteus superior, 171 gustatorius, 1^7 haemorrhoidahs inferior, 17* hepatici, 180 hypoglossalis, 157 iho-hypogastricus, 1 68

inguinalis, 168 incisorius, 147

infra-mandibularis facialis, 153 orbitales nervi facialis.

X53

orbitalis, 144 trochlearis, 143 intei costales, 166 iotercosto-cutanei anteriores,

166 intercosto • cutanei laterales

166 intercosto humer.Uis, 166

INDEX

261

interosseous anticus, 164 posticus, 165 ischiaticus magnus, 173

par v us, 172 labialis, 1^5 lachrymahs, 143 laryngeus externus, 156 inferior, 156 superior, 156 Hngualis, 147, 154 iumbales rami anteriores, 167 posteriores, 167 lombo-sacralis, 167 malaris nervi facialis, 153 raassetericus, 146 maxillaris inferior, 146 superior, 144 median us, 163 motor oculi, 143 musculo-cutaneus brachii, 163 cruris, 175 spiralis, 165 mylo-hyoideus, 147 nasalis, 143 naso-palatmus, 145 obturatorius, 168

articularis, 169 occipitalis major, 159 minor, 160 ffisophageales, 15: olfactorius, 141, 230 ophthalmicus, 143 opticus, 141 orbitalis, 144 palatinus magnus, 145 externus, 145 minor, 145 palmaris cutaneus, 164

ulnaris profundus, 165 superficialis, 166 palpebrales, 145 patellaris, 170 perforans Casserii, 164 perinaeales superficiales, 173 peronealis, 175 petrosus superficialis externus,

152 petrosns superficialis magnus,

152 petrosus superficialis parvus,

u148 •

pharyngei, 134

pharyngeus, 146, 154, 156 phremcus, 160 plantaris externus, 174

profundus, 174 internus, 174 pneumogastricus, 155

Nerv., popliteus externus, 174

internus, 173

pterygoidei, 146

pudendus inferior, 171

internus, 171

pulmonares anteriores, 1 56 posteriores, 156 radialis, 165

recurrens articularis, 175 renales, 176

sacrales, rami anteriores, 170 posteriores, 170 saphenus externus, 174 internus, 170 sciaticus magnus, 173 parvus, 172 spermatici, ifo spheno-palati ii, 144 splanchnicus major, 178 minor, 178 minimus, 178 splenici, 180

stylo-hyoideus, 152 suboccipitalis, ratnu

s anterior,

159

suboccipitalis, ramus pos- terior, 158 subscapulares, 162 superficialis cordis dexter, 17(8 sinister, ijj supra - mandibularis nervi

facialis, 153 supra-orbitalis, 143 scapnlaris, 162 trochlearis, 143 sympatheticus abdominis, 180 cervicis, 176 pelvis, 180 thoracis, 178

temporales nervi facialis, 152 profundi, 146 superficialis, 152 temporo-facialis, 152

malar. 144 thoracic! anteriores, 162

laterales, 163 thoracicus posterior, 1 62 thyro-hyoideus, 158 tibialis anticus, 175

posticus, 173 trigeminus, 142 trochlearis, 143 tympanicus, 157, 154 ulnaris, 164 uterini, 181 vaginales, 181 Vidianus, 146 Ninth nerve, 153

262

INDEX

Nodule, 125

Nose, cartilages, 228 cavity of, 228 meatuses of, 228

Nuclei of medulla oblongata, 123 Nucleus caudatus, 138

lenticularis, 138 Nutritious artery of femur, 92

of humerus, 75 of tibia, 96 Nyraphae, 225

Obliquus abdominis externus muscle,

44 mternus muscle,

capitis inferior muscle, 32 superior muscle, 32 oculi inferior muscle, 23 superior muscle, 23 Obturator artery, 86 fascia, 47 membrane, 54 muscle, external, 54 internal, 54 nerve, 168 Occipital artery, 67 lobe, 131

Occipital vein, 100 sinus, 97 nerves, 159. 160 Occipito-atloid articulation, 3 ligaments, 3 axial ligaments, 3 frpntalis muscle, 21 Odontoid ligaments, 4 (Esophagus, connections of, 187 CEsophageal arteries, 81 nerves, 157

rninjj of diaphragm, 46 , X34

nerve, 141 Olivary body, 120

fasciculus, 121

Omentum, great, 199

lesser, 199

splenic, 199

Omo-hyoid muscle, 28

Ophthalmic artery, 71

ganglion, 150 nerve, 143 veins, 98 _ Opponens minimi digiti muscle, 39

pollicis muscle, 39 Optic commissure, 129 nerve, 141 thalamus, 128 tract, 129 Ora serrata, 242 Orbicular ligament of the radius, n

Orbicularis oris muscle, 24

palpebrarum muscle, 22 Organ of Corti, 236 Orifice of the urethra, 227

of the uterus, 227

of the vagina, 225 Ossicles of the tympanum, 23? Os uteri, externum, 226 internum, 227 Otic ganglion, 148 Otoliths, 236 Ovaries, 227

Palate, soft, 183 Palatine, arteries, superior, 70 artery, inferior, 67 nerve, external, 145 large, 145 small, 145 Palato-glossus muscle, -3.0

pharyngeus muscle, 30 Palmar arch, deep, 77

superficial, 78

nerve of the ulnar, deep, 164 superficial, 164 fascia, 36

Palmaris brevis muscle, 39 longus muscle, 36 Palpebrae, 237 Palpebral arteries, 72

ligament, 238 Pancreas, 194

connections, iv« Pancreatic arteries, 83

duct, 195

Pancreatico-duodenal arteries, 83 Papilla lachrymalis, 237 Papillse of the tongue, i3t Parietal lobe, 132 Parotid gland, 183 Patellar nerve, 170

plexus, 169 Pectineus muscle, 52 Pectoralis major muscle, 33 minor muscle, 3 3 Peduncle of the cerebellum, inferior,

125 Peduncle of the cerebellum, middle,

125 Peduncle of the cerebellum, superior,

125 Peduncle of the cerebrum, 126

of the pineal body, 129 Peduncular fibres, 138 Pelvic colon, 191 fascia, 47 plexus, 180 Penis, 220 Perforating arteries, of femoral, 92

of internal mammary, 6j

INDEX

263

Perforating arteries of the palm, 77

of the sole, 95

Perforans Casserii nerve, 164 Pericardium, 202 Perilymph, 234

Perinaeal artery, superficial, 87 fascia, deep, 47

superficial, 47 nerves, superficial, 172 Peritoneum, 196

of female pelvis, 197 of male pelvis, 190 Peroneal artery, 96

anterior, 96 nerve, 171 Peroneus brevis muscle, 56

longus muscle, 56 tertius muscle, 55 Peroneo-tibial articulations, 17 Pes hippocampi, 136 Petrosal ganglion, 154

sinus, inferior, 98 superior, 98

Petrosal nerve, external, 152 large, 152 small, 148 Peyer's glands, 190 Pharyngeal ascending artery, 68 nerve, 154 vein, 101 Pharynx, 185

muscles of, 29 openings of, 186 Phrenic artery, 63, 82

nerve, 160

Pia mater of the brain, 140 of the cord, 116 Pigment cells of choroid, 240

of iris, 241

Pillars of the abdominal ring, 44 of the fornix, 136 of the iris, 240 of the soft palate, 183 Pineal body, 129 Pinna, or auricle of the ear, 230 Pituitary body, 129 Plantar arch, artery of the, 97 arteries, 96, 97 fascia, 57 ligament, long, 19 nerve, external, 174 internal, 174 Plantaris muscle, 55 Platysma myoides muscle, 26 Pleurae, 212 Plexus, aortic, 180

brachial, 161

cardiac, superficial, 179

Plexus, cardiac, deep, 179 carotid, 177 cavernous, 177 cervical, 159 choroides cerebri, 137 coeliac, 180

coronary, anterior, 180 posterior, 180 of the stomach,

1 80

diaphragmatic, 180 gulae, 155 hamorrhoidal, 180 hepatic, 180 hypogastric, 180 lumbar, 167

mesenteric, inferior, 180 superior, 180 oesophageal, 155 ovarian, 181 patellar, 169 pelvic, 180 pharyngeal, 176 prostatic, 181 pterygoid of veins, too pulmonary, anterior, 15^ posterior, 157 renal, 180

supra, 180 sacral, 171 solar, 179 spermatic of nerves, 180

of veins, 106 splenic, 180 tympanic, 154, 177 uterine, 181 vaginal, 181 vesical, 180 Plica semilunaris, 237 Pneumogastric nerve, 155 Pomum Adami, 207 Pons Varolii, 122

structure of, 1 2 3 Popliteal artery, 92 glands, 113 nerve, external, 174 internal, 173 vein, 109

Popliteus muscle, 56 Portal vein, 107 Porus ppticus, 242 Posterior commissure, 128

ligament of the knee,

pyramid, 120 Poupart's ligament, 44 Pouch, laryngeal, 210 Prepuce, 221

264

INDEX

Princeps cprvicalis artery, 63

pollicis artery, 77 Processus cochleariformis, 233

vermiformis, 124 Pi ofunda artery, inferior, 76

of the neck, 64 of the thigh, 91 superior, 75 Promontory, 231 Pronator quadratus muscle, 37 radii teres muscle, 36 Prostatic gland, 220

connections, 220 urethra, 221 sinuses, 221

Psoas magnus muscle, 51 parvus muscle, 5 i Pterygoid arteries, 70

nerve, external, 146 internal, 146 plexus of veins, 100 Pterygoideus externus muscle, 25 internal muscle. 25 Pterygo-maxillary ligament, 25

palatine artery, 70 Pubp-prostatic ligaments, 48 Pudic arteries, external, 91 artery, internal, 87 nerve, internal, 171 Pulmonary artery, 214 nerves, 156 veins, 106 Pylorus, 187 Pyloric arteries, 83 Pyramid, anterior, 120

decussation of, 120 of the cerebellum, 125 of the tympanum, 232 posterior, 119 Pyramidal fibres of the medulla, 12

masses of kidney, 217 i'yi amidalis abdominis muscle, 45

nasi muscle, 23 Pyramids of Malpighi, 217 Pyriformis muscle, 53

Quadratus femoris muscle, 54

lumborum muscle, 45

Radial artery, 76

nerve, 165

veins, 102

Radialis indi^is artery, 77 Radio-carpal articulation, 12 Radio-ulnar articulations, n Ranine artery, 66

vein, 101 Raph6 of the corpus callosum, 135

of the medulla, 118

Keceptaculum chyli, no Recto-resical fascia, 48

pouch, 197 Rectus abdominis muscle, 45

capitis anticus major muscle,

31 minor muscle,

31

lateralis muscle, 31 posticus major muscle,

32 minor muscle,

32

femoris muscle, 52 oculi externus muscle, 23 inferior muscle, 23 internus muscle, 23 superior muscle, 23 Rectum, connections of, in the

female, 191 Rectum, connections of, in the

male, 191

Recurrent interos&tous artery, 78 radial, 76 tibia!, 97

ulnar, anterior, 78 posterior, 78 Recurrent nerve of pneumogastric,

*55

Recurrent nerve of the tibial, 175 Renal artery, 84 plexus, 180 vein, 106

Restiform body, 119 Kete testis, 224 Retina, 242

Retrahens aurem muscle, 22 Rhomboideus major muscle, 41 minor muscle, 41 Rima of the glottis, 210 Risorius muscle, 25 Root of the lung, 213 Rotatores dorsi muscles, 43 Round ligament of the hip-joint, 14 of the liver, 192 of the uterus, 227

Saccule of the ear, 235 Sacculus laryngis, 210 vestibuli, 235 Sacral artery, lateral, S3 middle, 85 ganglia, 180

nerves, anterior branches, 170 posterior branches,

170

plexus, 171

Sacro-coccygeal articulation, 8 iliac articulation, 7 vertebral articulation, 6

INDEX

265

Sacro-sciatk ligament, large, 7 small, 7

Salpingo-pharyngeus muscle, 30 Salvatella vein, 101 Saphenous vein, external, 108 internal, 108 opening, 50 nerve, external, 174 internal, 170 Sartorious muscle, 51 Scala tynipani, 235 vestibuli, 235

Scalenus anticns muscle, 31 medius muscle, 31 posticus muscle, 3* Scapular artery, posterior, 63 ligaments, 9 muscles, 34

Scapulo-clavicular articulation, 9 humeral articulation, 10 Schneiderian membrane, 229 Sciatic artery, 89

nerve, large, 173 small, 172

Sclerotic coat of the eye, 239 Scrotum, 222 Second nerve, 141

Secondary membrane of the tym- panum, 231

Semicircular canals, 234 Semilunar cartilages, 16 ganglia, 179 valves of aorta, 206

of pulmonary ar- tery, 205

Semi-membranosus muscles, 54 Seminal ducts, 224 Seminiferal tubes, 223 Semi spinalis coli muscle, 43

dorsi muscle, 43 Semi-tendinosus muscle, 54 Septum auricularum, 204 cochleae, 236 crurale, 50

intermuscular, of the arm, 34 of the thigh,

49

iucidum, 136 nasi, 229 pec tini forme, 221 scroti, 222 of the tongue, 182 ventriculorum, 204 Serratus magnus muscle, 33 posticus inferior, 41 superior, 41 Seventh nerve, 151

Sheath of the rectus, 45 Shoulder-joint, 10 Sigmoid artery, 85 Sinus, cavernous, 98 circular, 98 coronary, 106 lateral, 98 longitudinal, inferior, 98

superior, 97 occipital, 98 petrosal, inferior, 98 superior, 98 pocularis, 221 prostaticus, 221 straight, of the skull, 98 transverse, 98 of Valsalva, 205 Sixth nerve, 151 Small intestine, 188 omentum, 199 Socia parotidis, 184 Soft commissure, 128 Soft palate, 183

muscles of, 30 Solar plexus, 179 Soleus muscle, 55 Spermatic artery, 84 cord, 2*2 plexus, 180 veins, 106 Spheno-palatine artery, 70

ganglion, 145 nerves, 144

Sphincter ani externus muscle, 48 internus muscle, 48 of the pupil, 241 vaginae, 49 Spigelian lobe, 192 Spinal accessory nerve, 157 arteries, 61 cord, 114

membtane of, 116 structure, 115 nerves, 158

roots of, 158 veins, 105

Spinalis dorsi muscle, 42 Spiral tube of the cochlea, 235 Splanchnic nerve, large, 178 small, 178 smallest, 178 Spleen, 195

connections, 195 Splenic artery, 83

omentum, 199 plexus of nerves, 180 vein, 107

266

INDEX

Splenius capitis muscle, 41

colli muscle, 42 Spongy bones, 228

part ofjthe urethra, 223 Stapedius muscle, 234 Stapes bone, 233 Stellate ligament, 5 Stenson's duct, 184 Sterno-clavicular articulation, 8 cleido-mastoid muscle, 26 hyoid muscle. 28 thyroid muscle, 28 St9mach, form and divisions, 187

connections of, 188 Straight sinus, 98 Striate body, 137 Stylo-glossus muscle, 29 hyoid ligament, 5 muscle, 28 nerve, 152 mastoid artery, 68 maxillary ligament, 25 pharyngeus muscle, 30 Subanconeus muscle, 35 Subarachnoid space, 140 Subclavian artery, left, 59

right, 59 vein, 103

Subclavius muscle, 33 Subcostales muscles, 46 Subcrureus muscle, 52 Subcutaneous mala? nerve, 144 Sublingual artery, 66 gland, 185 Submaxillary ganglion, 148

gland, 184

Submental artery, 67 Suboccipit a 1 nerve, anterior branch,

159 Suboccipital nerve, posterior branch,

158

Subpeduncular lobe, 124 Subpubic ligament, £ Subscapular artery, 74 nerves, 162

Subscapularis muscle, 34 Sulci of brain, 131

Sulcus, longitudinal, of the liver, 193 spiralis, 236 transverse, 193 Superficialis cervicahs artery, 63

volae artery, 76

Supinator radii brevis muscle, 38 longus muscle, 37 Supra-orbital artery, 72 nerve, 143 renal capsule, 217 plexus, i So

Supra-scapular artery, 62 nerve, 162 spinatus muscle, 34 trochlear nerve, 143 Suspensory ligament of the lens, 243 of the liver, 192 ^ of the penis, 220 Sympathetic nerve in the abdomen,

1 80

in the head, 176 in the neck, 176 in the pelvis, 180 in the thorax. 178 Symphysis pubis, 8 Synarthrosis, i

Taenia hippocampi, 136

semicircularis, 138 Tarsal artery, 94 plates, 237

Tarso-metatarsal articulations, 20 Teeth, 181 Tegmentum, 127 Temporal aponeurosis, 25 arteries, deep, 69 middle, 69 superficial, 68 fascia, 25 muscle, 25 nerves, deep, 146

superficial, 152 vein, 99

Temporo-fascial nerve, 152 malar nerve, 144 maxillary articulation, 4 sphenoidal lobe, 133 Tendo Achillis, 55

palpebrarurn, 228 Tendon of quadriceps extensor

muscle, 52

Tensor fasciae femoris muscle. 51 palati muscle, 30 tarsi muscle, 22 tympani muscle, 224 Tentorium cerebelli, 139 Teres major muscle, 34 minor muscle, 34 Testes, 223

Thalamus opticus, 128 Thebesian foramina, 204

valve, 205 Third nerve, 142

ventricle, 127 Thoracic duct, no

ganglia, 178 acromial artery, 74 alar artery, 74 long artery, 74

INDEX

267

Thoracic superior artery, 74 Tbymus body, 215 Thyro-arytenoid articulation, 209

ligaments, 209 Thyro-arytenoideus muscle, 30

epiglottidean ligament, 209 hyoid membrane, 209 muscle, 28 nerve, 158

Thyroid artery, inferior, 62 lowest, 80 superior, 66 axis, 62 body, 215 cartilage, 207 plexus of veins, 104 vein, inferior, 104 middle, 101 superior, 101

Tibial artery, anterior, 93 posterior, 94 nerve, anterior, 175 posterior, 173 veins, anterior, 109 posterior, 109 Tibialis anticus muscle, 55 posticus muscle, 56 Tibio-tarsal articulation, 19 Tongue, 181

muscles of, 29, 183 Tonsil, 183 Tonsillitic artery, 67 Torcular Herophili, 98 Trabeculae rarneae, 205 Trachea, 211

Trachelo-mastoid muscle, 41 Tragus, 230 Transverse colon, 190

fissure of the cerebrum,

130

of the liver, 193 ligament of the aceiabu-

lum, 14 of the atlas, 3 of the fingers,

14

of the knee, 17 of the meta- carpus, 14 of the meta- tarsus, 20 of the toes, 21 perineal artery, 87 sinus, 98

tarsal articulation, 20 Transversalis abdominis muscle, 44 cervicalis artery, 65 colli muscle, 42

' Transversalis faciei artery, 69 Transversus perinaei muscle, 49 Trapezius muscle, 40 Trapezoid ligament, 9 Triangular cartilage of the nose,

228

fascia, 44 nbro-cartilage of wrist,

12

ligament of urethra, 49 surface of bladder, 210 Triangularis sterni muscle, 46 Triceps extensor cubiti muscle, 35 Tricuspid valve, 203 Trigeminal nerve, 142 Trigonum vesicae, 219 | Trochlear nerve, infra, 142 supra, 143

Tube of the cochlea, 235 Tuber cinereum, 129 Tubercle of Rolando, 119 Tubuli seminiferi, 223 Tunica albuginea testis, 223 Ruyschiana, 240 vaginalis, 223 vasculosa testis, 223 Turbinate bones, 228 Twelfth intercostal nerve, 167 Tympanic artery, 6p, 71 Tympanum, 231

Ulnar artery, 77 nerve, 164 veins, 101

cutaneous anterior, 101 posterior, TOI Ureter, 217 Urethra, female, 225

orifice of, 225 male, interior, 221 Uterine arteries, 86

plexus of nerves, 181 veins and sinuses, 109 Uterus, 226

interior of, 226 ligaments of, 227 connections of, 226 Utricle of the ear, 235 Uvea iridis, 241 Uvula cerebelii, 125 palati, 183

Vagina. 225 Vaginal arteries, 86 plexus, 181 veins, 109 Vagus nerve, 155 nucleus u?

268

INDEX

Vallecula, 124 Valve, Eustachian, 204 of caecum, 125 mitral, 206 semilunar, 204 of Thebesius, 205 tricuspid, 205 ofVieussens, 124 Valvulae conniventes, 185 Vas deferens, 223 Vasa brevia, 188

efierentia testis, 224 rete testis, 224 vorticosa, 240 Vascular coat of eye, 240 Vastus externus muscle, 51 internus muscle, 52 Vein, alveolar, 99 angular, 99

ascending cervical, 101 lumbar, 104 pharyngeal, 102 auricular posterior, 100 axillary, 102 azygos, large, 104 small, 104 superior, 105 basilic, 102 brachial, 102 bronchial, left, 105

right, 105

cardiac, anterior, 106 great, 106 small, 1 06 cava, inferior, 105 superior, 103 cephalic, 102 cerebellar, 97 cerebral, 97 chproid, 97 ciliary, anterior, 98 posterior, 98

circumflex iliac, 108, 109 coronary of the heart, 106

of the stomach, 107 ,1 the corpus striatum, 97 deep cervical, 101 dorsal of the penis, 109 dorsi spinal, 105 emissary, 99 epigastric, deep, 109

superficial, 108 facial, 99 femoral, 109 frontal, 98 of Galen, 97

gastro-epiploic, 108 hacmorrhoidal, 109

Vein, hepatic, 106

iliac, common, no external, 109 internal, 109 infra-orbital, 99 innominate, 103 intercostal, 105

superior, left, 104

right, 104

jugular, anterior, 100 external, 100 internal, left, 101

right, 101 laryngeal, 101 lingual, loi

longitudinal of the spine, an- terior, 105 lumbar, 105

mammary, internal, 104 maxillary, internal, 100 median of the arm, 102 basilic, 102 cephalic, 102 mesenteric, inferior, 107 superior, 107 occipital, TOO ophthalmic, 98 ovarian, 106 palpebral, inferior, 99 superior, 99 pancreatic, 108 perineal, superficial, no pharyngeal, 101 phrenic, inferior, 106 popliteal, 109 portal, 107

posterior, spinal plexus of, 105 profunda, of the thigh, 109 pterygoid plexus, 100 pudic external, 108 internal, no pulmonary, 106 radial cutaneous, ioa ranine, 101 renal, 106 sacral, lateral, no middle, no

saphenous, external, 108 internal, 108 spermatic, 106 spinal, 105 splenic, 107 subclavian, 103 supra-orbital 99 renal, 106 scapular, 100

thyroid, inferior,

104

INDEX

269

Vein, thyroid, middle, 101

superior, 101 tibia!, anterior, 109 posterior, 109 transverse-cervical, 100 ainar, 101

cutaneous, anterior, xoz posterior, 101 uterine, 109 vaginal, 109 of the vertebrae, 105 vertebral, 101 vesical, 109

Velum interpositum, 137 Vena cava, inferior, 105 superior, 104 portas, 107

Ventricles of the brain, 127, 135 fifth, 136 fourth, 120 lateral, 135 third, 127 of the heart, 205

left, 206 right, 205 of the larynx, 210 Vermiform appendix, 190 processes, 124

Vertebral artery, 61 .

vein, 101

Verumontanum, 221 Vesica urinaria, 218 Vesical artery, inferior, 86 superior, 86 plexus of nerves, 180

of veins, 109 Vesicula prostatica, 221 Vesiculae seminales, 224 Vestibule of the ear, 234

of the vulva, 225

Vestigial fold of the pericardium, 203 Vidian artery, 70 nerve, 146 Vitreous body, 242 Vocal cords, 210 Vulva, 224

Wharton's duct, 185 White commissure of the cord, 116 Winslow's foramen, 201 Wrisberg's nerve, 163 Wrist-joint, 12

Yellow spot of eye-ball, 242

Zygomaticus major muscle, 24 minor muscle, 24

THE END

Bailliere, Tindall and Cox, 8, Henrietta Street,

UNIVERSITY OF CALIFORNIA

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