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Show 1870.] MYOLOGY OF PLATYDACTYLUS JAPONICUS. 417 from the humerus immediately beyond the insertion of the deltoid, the other dorsad of the insertion of the infraspinatus, commencing immediately distad of the insertion of the teres minor. The scapular section, or long head, arises from the posterior edge of the scapula, just above the glenoid cavity, by a flat tendon, which is further strengthened by an aponeurosis, which is attached to the head of the humerus, binding down the teres minor ; the inner section occupies the internal surface of the humerus, commencing beyond the subscapularis, between coraco-brachialis and latissimus dorsi. The united muscular mass of these origins occupies the dorsal surface of the humerus, and is inserted into the proximal extremity of the ulna, developing a sesamoid bone or olecranon iu the tendon. Levator scapulae arises by two heads, one from the scapula and clavicle, close to the articulation between those two bones, the other from the cartilaginous suprascapular; they pass forwards, and are inserted together into the transverse process of the first cervical vertebra or atlas. Subscapularis arises from a small part of the outer surface of the scapula covered by the infraspinatus, and from the whole internal surface of that bone, with the exception of the posterior superior angle, and from the interior inferior angle of the suprascapula, also from tbe upper two-thirds of the inner surface of the coracoid; the fibres converge and are inserted into the inner and lower edge of the head of the humerus, close to the capsular ligament. This evidently corresponds to the subscapularis, and perhaps the dorsal part to tbe teres major, as it is partially separable from the remainder at its insertion, which is a trifle beyond that of the rest of the muscle. Sterno-coracoidalis arises from the anterior and lower part of the internal and lower surface of the coracoid, occupying rather more than one-sixth of its superficies, slightly overlapping the edge of the last muscle, and is inserted into the antero-lateral edge of the sternum. Some of its fibres proceed further back, and are inserted into the anterior extremity of xiphisternum and into the cartilages of the second and third sternal ribs. Serratus consists of two distinct parts. The anterior section arises from the whole length of the suprascapula, and, passing downwards and forwards, is inserted by three slips into the expanded terminations of the three anterior cervical ribs. The posterior section arises from the postero-inferior border of the scapula and suprascapula, and, passing downwards and backwards, is inserted into the extremities of the fourth and fifth cervical ribs. From this there is a continuation in the same direction to the xiphisternum and cartilages of the fourth and fifth sternal ribs, the whole being parallel with the fibres of the obliquus externus abdominis. Flexor carpi radialis arises from the upper part of the inner or flexor condyle of the humerus, and from the proximal two-thirds of the radius, and is inserted into a bone of the carpus which appears to correspond with the scaphoid. Flexor carpi ulnaris arises from the lower part of the inner condyle |
