Part 17

59 124 Side view of fore part of a Monkey’s skeleton.

60 126 A section, from side to side, through the Elbow-joint, showing the shape of the surfaces of the bones. A, the radius; B, the ulna; CC, the side ligaments holding the radius and ulna to the arm-bone, D.

61 127 The upper limb with the forearm and hand in the state of supination. A, the long Pronator muscle.

62 127 The same in a state of pronation. B, the short Supinator muscle.

In this and the preceding drawing a plumb-line, descending from the outer condyle of the humerus traverses the lower end of the ulna and the ring finger.

63 131 Drawing of the biceps muscle. The hand is in a state of pronation. Driving the gimlet is effected by the movement to the state of supination.

64 134 Section, from side to side, through the Wrist, showing the shapes of the bones and the mode in which they are adapted to one another. A, the radius; B, the ulna; C, scaphoid bone; D, cuneiform bone; E, semi-lunar bone; F, line of contact of radius and ulna; G, G, side ligaments connecting the wrist-bones with the bones of the forearm. H, I, K, L, M, metacarpal bones of thumb and fingers.

65 138 View of the superficial muscles on the palmar aspect of the forearm and hand. A, the radial flexor of the wrist. B, the long palmar muscle. C, the ulnar flexor of the wrist. D, the muscles of the “ball of the thumb.” E, the long supinator muscle. F, the long pronator. G, the lower part of the biceps muscle. H, Cross ligaments binding the tendons in their places. (This and the two following figures are from Quain’s Anatomy.)

66 138 View of the deep muscles and tendons on the palmar aspects of the forearm and hand. A, the long flexor of the thumb. B, some of the flexors of the fingers. C, the Adductor muscle of the thumb.

67 139 The extensor muscles and tendons of the wrist, thumb, and fingers seen on the back of the forearm and hand. A, A, A, the abductors and adductors of the fingers. B, B, the cross ligament which binds the tendons in their places.

68 146 Hand holding a cricket-ball, showing that the tips of the fingers and the thumb all reach the same level.

69 152 Diagram showing the distribution of the median (A) and ulnar (B) nerves in the hand.

70 165 Drawing of a magnified section through the skin of the palmar surface of the thumb, including three of the ridges seen on that surface. a, the outer or horny layer of the cuticle; b, the deeper layer of the same called “rete mucosum;” c, c, c, the cutis, with papillæ rising from its surface beneath the ridges and projecting into the rete mucosum; g, g, grains of fat lying in the deeper part of the cutis and in the tissue beneath it. Between f and f are three sweat-glands, each composed of a tube rolled up into a ball or knot. The tubes (h, h) are seen ascending from them through the cutis and cuticle, and opening at the tops of the ridges. (From Kölliker’s Mikroskopishe Anatomie.)

71 170 Section of skin still more magnified. a, Outer or horny stratum of cuticle; b, inner stratum of cuticle, or “rete mucosum;” c, papillary stratum of cutis; d, deeper or fibrous stratum of cutis. The curling tube rolled into a ball at the lower part is the sweat-gland. Its duct is seen ascending through the fibrous structure of the cutis, and presents the coiled appearance of a rope as it traverses the cuticle.

72 170 A few layers of the cuticle and rete mucosum of a Negro, showing the spots of dark pigment in the rete which give the black colour to the Negro’s skin. (This and the preceding from Todd and Bowman’s Phys. Anatomy.)

73 170 Section of a Corn and adjacent skin. a, the cuticle; c, the cutis with its papillæ. The cuticle is seen to be very thick, and the papillæ are somewhat enlarged in the corn.

74 170 Section of a Wart and adjacent skin. a, cuticle; c, the cutis with its papillæ. The latter are seen to be enlarged, or “hypertrophied,” in the wart.

75 174 Vertical section, made lengthways, of a Nail raised from its bed, showing its connexion with the cuticle. a, a, cuticle; d, d, nail.

76 174 Similar section of a Nail lying in its bed of cutis. a, cuticle; b, rete mucosum; c, cutis; d, nail.

77 174 Section of the Cutis from which the nail, the cuticle, and the rete have been removed.

78 176 Transverse section of the Nail and Skin, made vertically. a, a, cuticle; b, rete; c, c, cutis; d, d, lines running through the cutis to the papillæ; e, e, e, lines running through the nail to the rete. (This and the three preceding from Kölliker.)

79 179 Section of a Hair and Hair-follicle. a and b, the cuticle and rete lining the follicle. e, the outer layer, or rind, of the hair formed by closely-plaited scales of cuticle continued upon it from the bottom of the follicle d.

80 179 Piece of the exterior of a Hair more highly magnified to show the imbricated arrangement of the plates or scales forming its outer surface.

81,82 179 Transverse sections of Hairs. (These and two preceding from Todd and Bowman.)

83 181 Section of a Hair-follicle containing a Hair, and with two Oil-glands, g, g, lying near it, and with their ducts opening into it. a and b, cuticle and rete; d, bottom of follicle. (From Kölliker.)

84 187 The terminal Bone of a finger, with a portion of the bone next it, showing the nodulated bulbous end of the former.

CAMBRIDGE: PRINTED AT THE UNIVERSITY PRESS.

By the same Author.