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Show 188 MR. F. J. BELL ON MOSCHUS MOSCHIFERUS. [Feb. 1, digits, whereas, it will be remembered that, in the manus, the lateral digits also received tendons from this muscle; but the lateral toes of Moschus, in the pes, are much smaller than those in the manus, and the metatarsals are absent, as has been pointed out by Prof. Flower. In Hyomoschus, and the Pig, tendons are sent to all four digits. The tendon of the oblique flexor, after having passed through the strong fibrous sheath found on the inner side of the tarsus, becomes directly afterwards united with that of the perforans; in the Sheep the union takes place somewhat lower down the metatarsus, in Cervus at about the same spot. D. Muscles of the pes. The pedal is a small muscle, arising from the inner face of the calcaneum, and attached to the tendon of the common extensor; it has • no attachment to the inner extensor as in the Sheep and Deer; nor has it two branches for attachment to the two tendons of the common extensor as in Hyomoschus and the Pig. There are no interosseous muscles, of which there are four in Hyomoschus and the Pig. SUMMARY. The most interesting points in the foregoing description are those which refer to the arrangement of the tendons inserted into the digits. i. They are interesting morphologically, as showing what was the arrangement in the common ancestor of the true Cervidae and of Moschus-namely, that the extensor communis digitorum had only two tendons, and those for the median digits; for the same character obtains in Tragulus ; while they offer a further proof of Prof. Flower's positions: - (a) That Moschushns close affinities to the true Cervidae; for this same arrangement seems to be constant throughout the group, although different in Hyomoschus*. (3) That Moschus is an older and more generalized form ; inasmuch as it still possesses tendons for the lateral digits, arranged in the same manner as in Tragulus. The absence of flexor tendons, arising from the perforans, and inserted into the lateral digits of the pes, may cause further stress to be laid on the small size or complete absence of the metatarsals, which is so highly characteristic of the Cervidae. ii. They are interesting physiologically, as showing how the Musk- Deer managed to hold on to the rocks and crags of its home by all four toes, in the manner described in Prof. Flower's paper. It will not, I trust, be long before we know what arrangement obtains in the Reindeer, in Hydropotes, and others. I trust that the evidences adduced on the subject of the homology of the perforated tendon of the pes in the Ungulata, may settle this question, so far, at any rate, as the gastrocnemius is concerned. * The vagueness of some parts of M. Chatin's description demands a reconsideration of the myology of Hyomoschus. |
