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Show 240 MR. F. E. BEDDARD ON [Apr. 7, insertion is on to humerus by tendon in common with the teres major ; it gives off, as is so usually the case in this group of animals, a dorso-epitrochlear slip which runs to elbow. The Teres major arises from about the upper half of the posterior margin of the scapula ; it is inserted, as already mentioned, in common with the latissimus dorsi by a flat tendon about half an inch long and rather more than half an inch broad at its insertion. The Deltoid consists of two more or less distinct portions-one arising from the spine of the scapula and apparently also from the fascia covering the infraspinatus ; the smaller part of the muscle springs from the acromion and metacromion ; the two are inserted in common on to the deltoid ridge by an insertion which is fleshy above but tendinous below. The Pectoralis primus is much blended with the panniculus carnosus; its insertion is shown in the accompanying drawing (woodcut, fig. 3) to extend a long way down the humerus. The Triceps consists of four distinct parts, or of five if the dorso-epitrochlear be reckoned as belonging to the Triceps. The first part arises from scapula and also from the fascia covering the infraspinatus ; the second part is blended at its origin with the insertion of the infraspinatus ; it arises from the neck of the humerus and from the deltoid ridge. The third part is smaller ; its origin is tendinous from the neck of the humerus just below the insertion of the teres major and latissimus dorsi. The fourth part is entirely fleshy and arises from the greater part of the shaft of the humerus. The Coraco-brachialis arises from the coracoid by a strong flat tendon ; its insertion is also tendinous for the greater part and extends for some way down the humerus, beginning with the head; the posterior part of its insertion is fleshy. The Biceps has only a single origin and a single insertion on to the ulna. The biceps is also inserted in common with a peculiar muscle shown in the accompanying drawing (woodcut, fig. 3, x) ; this muscle arises by two fleshy heads from the humerus, one on either side of the insertion of the pectoralis. The Brachialis anticus curves round the arm as it does in other Rodents ; it has a tendinous insertion on to the ulna beyond that of the biceps. The Pronator radii teres is not a very strong muscle ; it arises from the outer condyle of the humerus and is inserted on to the radius. The Flexor metacarpi radialis is the next muscle to the pronator radii teres; it is attached by a long tendon to the second metacarpal (== 3rd digit) near to the proximal end. The Flexor carpi ulnaris is attached in the usual way by a very stout tendon. The Flexor sublimis arises in common with the flexor profundus; it divides into three delicate tendons which supply digits 2, 3, and 4. The Flexor profundus and Flexor pollicis longus are difficult to distinguish ; the common tendon arises from the fusion of four more or less distinct muscular heads. Two of these arise from the |