Part 94

34. Pronator teres (p. 179, and Fig. 77, q).

35. Flexor carpi radialis (p. 179, and Fig. 77, r). The tendon of the flexor carpi radialis should not be traced to its insertion until the deep muscles of the palm of the hand have been dissected.

36. Abductor brevis pollicis (p. 184, and Fig. 77, w).

37. Flexor carpi ulnaris (p. 180, and Fig. 77, t).

38. Palmaris longus (p. 179, and Fig. 77, s). In dissecting this muscle be careful not to injure the part of the flexor sublimis (Fig. 77, x) that rises from its surface (see flexor sublimis, p. 181). Cut the palmaris proximad of the origin of the flexor sublimis and reflect it.

39. Flexor sublimis digitorum (p. 181 and Fig. 77, x). Trace one or two of the tendons through the sheaths on the ventral surfaces of the first phalanges. Cut and reflect the radial portion.

40. Flexor profundus digitorum (p. 181, and Fig. 77, u). After recognizing the parts cut through the tendons of the first and fifth parts and reflect them to determine their origin. Then cut through the common tendon so as to reflect the other three parts together. Trace one or two of the tendons to the distal end of the digit.

41. The supinator (p. 177, and Fig. 85, b).

42. The extensor brevis pollicis (p. 178, and Fig. 85, a).

43. Pronator quadratus (p. 183, and Fig. 87, a).

The insertion of the brachialis and clavobrachial (Fig. 87, c) and of the biceps (Fig. 87, b) should now be examined.

There remain to be dissected the small muscles of the palm of the hand. If these have been injured on the side dissected, the hand of the other side may be used.

44. The lumbricals (p. 184, and Fig. 88, f).

45. The flexor brevis pollicis (p. 184, and Fig. 89, a).

46. The adductor pollicis (p. 185, and Fig. 89, b).

47. The abductor digiti quinti (p. 185, and Fig. 89, i).

48. The flexor brevis digiti quinti (p. 186, and Fig. 89, h). Cut and reflect it.

49. The opponens digiti quinti (p. 186, and Fig. 89, g). Cut and reflect it.

50. The interossei (p. 185, and Fig. 89).

IV. MUSCLES OF THE NECK AND THE DEEP MUSCLES OF THE HEAD.

If the superficial muscles of the head have been dissected according to the directions above given (p. 434), the skin of the head and neck, and the external ear, will have been removed, and the specimen is ready for further study. The parotid and submaxillary glands (Fig. 65, 1 and 2) should be removed if this has not been done; also the lymphatic glands (Fig. 65, 3).

If the superficial muscles of the head have not been dissected and are not to be, remove the skin from the side of the neck, head, and face to the median dorsal line, removing the thin superficial muscles with the skin. Remove also the parotid, submaxillary, and lymphatic glands (Fig. 65, 1, 2, and 3), and cut through the ear-muscles and the cartilaginous auditory meatus (under direction) and remove the external ear. Clean fat, connective tissue, etc., from the surface of the muscles of the thorax, neck, and head; then dissect as follows:

1. The sternomastoid (p. 139, and Fig. 65, g). Transect and reflect it.

2. The cleidomastoid (p. 120, and Fig. 65, h). This has already been transected; examine now its origin.

Remove the large lymphatic gland beneath the sternomastoid and close to the tympanic bulla, and clean the surface of the muscles in this region.

3. The levator scapulæ ventralis (p. 120, and Fig. 72, c, c′, c″). This has already been cut; study now its origin.

4. The sternohyoid (p. 140, and Fig. 65, e). In raising it begin at the cranial end and take care not to injure the subjacent sternothyroid (Fig. 65, g′). Transect.

5. The sternothyroid (p. 141, and Fig. 65, g′). Transect.