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Show 1882.] ANATOMY OF PROTELES. 583 large slip which is inserted into the annular ligament of the wrist. In other respects it resembles that of II. crocuta. The extensor minimi digiti of Proteles resembles that of H. crocuta in being inserted into the two outer toes, and differs from that of Viverra, which gives off slips to the three outer toes. The extensor indicis in Proteles joins the extensor tendon which passes to the middle toe, and thus agrees with that of H. striata, and differs from that of H. crocuta, which joins the extensor tendon of the second toe. In Viverra the tendon of this muscle gives off slips to the 1st and 2nd toes. The palmaris longus of Proteles resembles that of H. crocuta, and differs from that of H. striata, the tendon of which blends with the superficial flexor tendons of the toes, as also from that of Viverra, which is double. The flexor carpi ulnaris of Proteles differs from that of H. crocuta and H. striata in possessing an olecranoid as well as a condyloid origin. In this respect Proteles resembles Viverra. The flexor carpi radialis resembles that of H. crocuta in being inserted into the base of the second metacarpal bone, and differs from that of Viverra, which is inserted into the first as well as the second metacarpal. The flexores digitorum of Proteles closely resemble those of H. crocuta for the most part, but differ inasmuch as that portion of the common muscle which represents the flexor perforatus digitorum divides only into three slips, which are distributed to the three middle toes, while in H. crocuta it divides into four slips, which are distributed to the four perfect toes. In this respect Proteles agrees with Viverra. In Proteles, moreover, the portion of the muscle which represents the flexor perforans divides into five slips, one of which passes to each of the toes; while in H. crocuta the tendon of the flexor perforans, in accordance with the reduction in number of the toes, divides only into four slips. The lumbricales in Proteles are three in number, and pass to the three outer toes. In H. crocuta there are four, one to each toe. In Proteles the flexor poliicis is incorporated with the flexor perforans digitorum ; whereas in H. crocuta, on account of the rudimental hallux, the flexor poliicis is entirely deficient. In H. striata, however, Meckel asserts the existence of this muscle. The interossei in Proteles, as in H. crocuta, are arranged in two layers, a superficial and a deep. The superficial layer includes two muscles, which differ from the corresponding structures \nH. crocuta inasmuch as they both arise from the base of the third metacarpal bone, instead of one from the third and the other from the fourth metacarpal as occurs in H. crocuta. The one passes to be inserted into the inner side of the base of the first phalanx of the fifth toe, whilst the other is inserted into the outer side of the base of the second toe. In H. crocuta these muscles are inserted into the outer and middle toes respectively. The deep layer consists of ten muscles arranged in pairs, two to PROC. ZOOL. Soc-1882, No. XXXIX. 39 |