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Show 406 DR. B. 0. A. WINDLE AND MR. F. G. PARSONS ON THE [Apr. 6, Summing up the above results, we find that in the Hyaenidae and Proteles the short thumb-muscles are absent, in the Canidae they are id-developed, while in the other families there is usually an abductor and flexor brevis, but occasionally a small opponens may be developed. Hgpothenar Muscles.-The minimus has, in all cases, a double flexor brevis, as have the other digits ; there is also an abductor minimi, which rises from the pisiform and is inserted into the inner sesamoid bone on the palmar surface of the head of the fifth metacarpal. Shepherd (XX.) describes an opponens minimi in Ursus americanus (40). Macalister (IX.) mentions two abductors of the little finger in Viverra civetta (13), while in Lutra cinerea (78) he found the usual abductor of that finger in two layers, as well as an additional one from the unciform. In our specimen of Canis familiaris (31) the abductor seemed to have missed its insertion into the sesamoid and to have acquired a new one into the fifth metacarpal, thus becoming an opponens. Adductor Muscles of the Hand (First la ver of deep muscles).- With regard to the layer of adductor muscles, which rise from the palmar ligaments of the carpus and lie superficial to the flexores Fig. 11. P/S-OPP. MW.O/O.. PDDWN. ffBD. POL . DD.POL. .0£EP BK. - o/. Oi. /*£». . -HOD /A/D, Manus of Canis familiaris, showing the deep muscles of the palm. breves of the fingers, there can be no doubt that the normal arrangement in the Carnivora is, one for the pollex, another for the index, and a third for the minimus; of these the one for the minimus is as a rule the largest, and that for the pollex the |