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Show 1876.J MR. F. J. BELL ON MOSCHUS MOSCHIFERUS. 183 In Tragulus a similar arrangement obtains. In Hyomoschus, however, Chatin notes three muscles in this region, which he names ex-tenseur gros, extenseur grele, and adducteur. The adducteur appears to be the same as the oblique extensor, so far as one can judge from Chatin's account; he does not, however, note the oblique direction of its tendons, which seems to be universal among the Ungulata, as it is found in Equus, Oris, Cervus, and Sus. The anterior extensor arises by two heads barely separable from one another, on the outer face of the distal portion of the humerus; and from Chatin's description and figure I am led to suppose that he has divided this, which is really one muscle, into a portion "gros," and a portion " grele." The tendon is only double at its distal extremity, where it widens, and becomes bifid, to embrace both sides of the tuberosity of the metacarpus. /3. Posterior face. (1) Flexor metacarpi internus. (2) ,, „ obliquus. (3) ,, „ externus. Here, again, there is no important variation; but we may note that the outer branch of the bifid tendon of the external flexor (3) is inserted into the tuberosity on the external side of the metacarpus, which appears as the proximal end of the fifth metacarpal, united to the rest of the bone in this region, and only represented distally by a short, fine needle of bone ; a similar insertion of the tendon was seen in Cervus virginianus ; in the Sheep the ending is more towards the median line of the metacarpus, while in Tragulus, Hyomoschus, and the Pig this branch is attached to the head of the entire fifth metacarpal. B. Muscles iuserted into the phalanges. a. Anterior face. In the arrangement of the tendons of muscles going to the digits, Moschus differs not a little from Cervus virginianus, or the Pig. In the former, as in the Sheep, we find that there are three muscles having their insertions in the digits, namely :- i. Extensor communis, with tendons to the third phalanges of the median digits. ii. Extensor digiti interni (tertii). iii. „ „ externi (quarti). Both of these have two branches-one to the second phalanx, and one directed backwards and ending in the plantar cushion-but no tendons going to the lateral digits, although those ending on the plantar surface, as just described, probably represent what remains of them. C. virginianus, in addition to the muscles common to it and the Sheep, possesses an extensor dig. minimi. |