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Show 1880.] DENTAL CHARACTERS OF THE CANIDAE. 269 we have seen, has commenced even in Otocyon. And I think there can be no reasonable doubt that the occasional appearance of an extra molar in domestic dogs is not a monstrosity, but a reversion to the earlier and more complete dentition of the primitive stock of the Canidae. In Icticyon the dentition is modified in the opposite direction, by the suppression of -^ and the reduction of - . Indeed this tooth was supposed to be absent altogether, until Professor Flower recently observed it in a specimen which has already been the subject of a communication to the Society. I am greatly obliged to the President for enabling me give a figure of the skull (fig. 15) and teeth (fig. 16) of the specimen in question, which, though not quite fully adult, has the complete permanent dentition. Fig. 16. Upper (A) and lower (B) cheek-teeth of Icticyon venaticus; 0, the right lower sectorial and second molar, from within ; D, the right upper sectorial, from within ; a, the accessory cusp; the inner anterior cusp is not sufficiently well defined. In the following table of measurements I add those of an imperfect skull in the British Museum. TABLE XIV.- -Cranial and Dental Measurements of Icticyon venaticus. I. Total length ll8 Lengtb of palate 56 Breadth „ • .••• 40 Length of basicranial axis .. 52 prn^J. 11-5 13 II. 59 41 |