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Show 1894.] ANATOMY OF PALAMEDEA CORNUTA. 545 represented by a broad tendinous slip. From this the thickened anterior edge goes to the longus and the broader thinner portion to the brevis. A band of tendon arising from the humeral ridge also runs to the brevis. The longus tendon passes straight along the edge of the patagium and gives off to the brevis a rather widish slip, which goes to the brevis just at the emergence of the nerve. The brevis tendon is thickened on the outer side; the nerve passes beneath the outer half of it and superficial to the inner half, but there are no signs of distinct division of the tendon into two. Just below the emergence of the nerve a branch is given off which is fused below with the fleshy head of the extensor metacarpi radialis. Another branch is given off on the outer side, which is inserted in common with the origin of the extensor metacarpi radialis tendon. The main part of the tendon passes towards the elbow, and ends on the radius by a short tendon. There is no biceps patagicdis. Teres major.-This arises from the whole of the outer border of the scapula. Its tendon is inserted on to the great tuberosity of the humerus distal to the biceps. Teres minor (supraspinatus).-This is an excessively delicate and slender muscle. It arises from the lower border of the scapula anteriorly, and is inserted on to the humerus between the two heads of the triceps. Subscapular is.-There are two heads of origin, from the anterior half of the under surface of the scapula ; the deep head is also from the coracoid. Both are fleshy, and the superficial muscle arises exactly above the scapular head of the deeper muscle, the first part of the serratus anticus being inserted between the two. The two parts of the muscle fuse about halfway between origin and insertion. Expansor secundariorum.-This arises fleshy from the quills covering the elbow-joint, and ends in a characteristically ciconiine manner. Biceps.-The long head arises in common with the deltoid ; the short head in common with the insertion of a portion of the pectoralis major. The latter head is narrow. The insertion of the muscle is double, and the division into two parts commences in the fleshy belly of the muscle. The radial tendon is more than twice the width of the other, and itself divides into two. Ancoiueus longus.-It arises by a forked tendinous head from the scapula, the lower head being thicker than the upper. There is a double accessory head formed by two equisized tendons separated by a space, across which run two tendinous bars. With the upper of these the tendon of the latissimus dorsi posterior is fused and the extreme superior tip of the latissimus dorsi anterior fuses with the lower accessory head. There is a broad tendinous insertion to the ulna, and on to the fascia covering the elbow-joint. Triceps.-This arises right clown the humerus, and the origin bifurcates above. |