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 

 Moschits, 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 Cervidse 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 Moschus has close affinities to the true Cervidse ; 

 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 in- 

 serted 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 Cervidse. 



ii. They are interesting physiologicalhy, 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 recon- 

 sideration of the myology of Hyomoschus, 



