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Show 1880.] DENTAL CHARACTERS OF THE CANID.F.. 263 T A B L E XL--Proportional Lengths of the Teeth in Procyonidse and Otocyon. Nasua. Procyon. Otocyon. Length of ^ 4 i6.6 16.6 u.y m- *- , - *. " 17*7 17*7 13*4 TO. 2 - 16 12*7 11*8 ™Tl 18'8 20-5 16*1 mT2 20 19*4 133 The teeth of Nasua and Procyon are larger (and notably thicker) than those of Otocyon ; moreover the hindermost molars, in their elongation and in other characters, tend towards the Ursine form. There is therefore no question of direct affinity between Nasua and Procyon and Otocyon ; it is simply that, in dental characters, the lowest type of canine animal approaches the less-differentiated Procyonidee. In Bassaris and in Procyon the form of the ramus of the mandible is similar to that in the ordinary Canidae ; in Nasua it approaches Fig. 14. A B C Right ramus of the mandible of Perameles (A), Procyon (B), and Otocyon (C), from behind : a, angular process ; c, condyle. that seen in G. cancrivorus; in Mlurus this peculiarity is still more exaggerated ; and in Cercoleptes we have a mandible which resembles that of Otocyon, with a still more developed lobe. As to the base of the skull, it appears to me that, taking Mlurus, Procyon, and Nasua together, the arctoid characters are so modified, and the approximation to the canine type of skull becomes so close, that they almost present a transition from the one type of skull to the other. I have elsewhere drawn attention to the fibrous epipubis of the Dogs as the homologue of the so-called "marsupial bone" of the |