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Show 1891.] ANATOMY OF THE KAGU. 15 way along the radius; soon after this the tendon joins that of the inner head. The inner part of this muscle has a fleshy origin, and it is larger than the outer part of the muscle ; its tendon commences nearer to the origin of the muscle than that of the outer head ; the combined tendons are inserted on to the metacarpal of digit i. Dr. Shufeldt, in his careful account of the myology of the Raven, [20], mentions only a single head to this muscle ; and the same thing occurs in other birds. (2) The Supinator is a strong muscle attached up to about the middle of the radius ; it is not in any way fused with the extensor communis digitorum, as I understand it to be in the Raven from Shufeldt's description. (3) The Extensor digitorum communis arises by a distinct tendon from the humerus in common with the supinator ; the muscle passes into its tendon of insertion at about the middle of the forearm ; the tendon passes round a smooth surface at the distal end of the ulna in common with that of the flexor metacarpi radialis, and is attached to the proximal end of the first phalanx of the index, having previously given off a branch to the thumb. In the Raven, according to Shufeldt, the insertion is on to the second phalanx of the index. (4) The Extensor pollicis longus arises chiefly from the radius, but also from the septum between itself and the anconaeus. (5) The Extensor indicis longus is formed of two parts-one head arising from the lower side of the radius near to its distal end, the other from the carpus. (6) The Ectepicondylo-ulnaris is a strong muscle, arising by a tendinous origin from the outer condyle of the humerus ; it is inserted along rather more than one half of the ulna. (7) The Extensor metacarpi ulnaris arises from the external condyle of the humerus; closely attached to it is a tendinous sheet connected with the tensor patagii brevis tendon ; it is inserted by a long tendon to metacarpus, which arises not far from the wrist-joint. (8, 9) There are two pronator muscles, of which the upper is the larger. (10) Flexor digitorum sublimis.-This muscle is visible when the skin is removed ; it is related to a strong tendinous sheet connected with the remiges ; the muscle itself is largely covered by the flexor carpi ulnaris ; its tendon divides into two, the shorter being attached to the wrist, the longer passing down in company with the tendon of the flexor digitorum profundus. (11) The Flexor digitorum profundus arises from a part of ulna just in front of attachment of brachialis interims ; it is for a very short space overlapped by this muscle; it also arises from radius ; the tendon ends upon proximal end of last joint of the 2nd finger. (12) The Flexor carpi ulnaris is a very large muscle arising by a strong tendon ; the distal extremity of the muscle divides into two tendons-one is short and strong and is attached to the ulnare ; the other passes down the index digit and is attached to metacarpal in. |