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Show 1879.] ANATOMY OF 11Y.ENA CROCUTA. 105 toe ; in this respect it differs from those in the Civet and Dog. to Meckel, in //. striata this muscle divides into two distinct bellies, and gives off five tendons. In the Civet the muscle is undivided. An extensor hallucis does not exist as a separate muscle, a slip from the tibialis anticus being its only representative. Tibialis anticus arises from the external surface of the upper third of the tibia; halfway down the leg the muscle divides into two, each division terminating on a separate tendon ; of these the one (tibialis anticus) is inserted into the entocuneiform bone, whilst the other (extensor hallucis) goes to the metatarsal of rudimentary great toe. There is no separate extensor hallucis proprius, such as exists in the Civet or Dog. Extensor brevis digitorum, from the os calcis, terminates by three tendons, which pass to the second, third, and fourth toes. The same obtains in H. striata. In the Civet the muscle is distributed to the four inner toes, whilst in the Dog it is to the four outer. Peroncei are two in number. Of these the longus arises as in H. striata, Bear, Coati, & c , from the external condyle of the femur ; it has also an additional origin from the external tibial tuberosity. Insertion is solely into base of fifth metatarsal bone, as in H. striata. In the Civet it is fibular in origin, and its tendon of insertion, after giving a slip to the fifth metatarsal, is continued to the first. The peronccus brevis arises below the longus from the middle two thirds of shaft of fibula, and terminates in two tendons, one of which passes on the dorsal aspect of the outer toe and joins the expansion of extensor-tendon, whilst the second is inserted into the base of the metatarsal bone of the same toe. In H. striata the first tendon joins the extensor of the fourth toe. In the Dog the insertion is as in H. crocuta. In the Civet, and in the Bear also, a third peronaeus exists ("peronaeus quinti," Macalister) which, as observed by Meckel, may represent the peronaeus tertius. It joins the extensor-tendon of the fifth toe over the first phalanx. The tendency towards the formation of a third peronaeus is well evidenced by the double insertion of the peronaeus brevis in the Dog, and the still better marked division inferiorly in H. crocuta. Comparing these with the Civet or Bear, a progressive and more complete differentiation obtains, up to the formation of entirely separate muscles. CONCLUDING REMARKS. Having now described at some length the anatomy of H. crocuta, it may be well to add a few words by way of comparison of the structure of this with that of the other species which most closely resemble it. The arrangement of the muscular system of H. crocuta, so far as one can judge from an inspection of the plates of Cuvier and Laurillard, and from a perusal of the somewhat fragmentary notes which have been published with reference to other species, appears to be very similar to that of H. striata and H. brunnea, and |