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Show 1902.] MUSTELA PAL/EATTICA. 113 to each other, but in the Turin specimen there is a slight emargi-nation on the posterior margin, internally from the third cusp ; and the same may be seen in a fine skull of M. palwattica from Pikermi, which forms part of Dr. A. Smith Woodward's recent successful excavations at Pikermi. In the Valleyres, Turin, and London specimens the interior margin of the tooth is slightly more elongate than the exterior, so that the anterior and the posterior margins converge slightly towards the outer sides. Conversely, in the Indian Martens (the M. Jiavigula- group) " this molar differs in form from that in M.foina and M. martes by having the inner lobe no broader from back to front than the outer." 1 On the whole the fossil tooth differs from the molars of the martes-group by slight characters only. Now, the only reason for collocating the fossil within the Melince has been the shape of this upper m. 1, with which of course goes hand in hand that of the talon of the lower m. 1. It is, however, to be considered that a tooth situated at the posterior end of the series is always liable to vary more or less, and within the Melinos in particular this tooth is by no means characteristic for the group. In Helictis it is quite narrow, the inner part not broader than the outer and the anterior and posterior margin almost parallel. In Meles the outer margin is much shorter than the inner, so that in this respect Meles agrees more with Mustela martes and allied species. In Mephitis and allies there is no trace of a third cusp, which, on the other hand, is present, although feebly developed, in the unworn molars of some species of Mustela (e. g., M. jyennanti, M. zibellina), as also in unworn specimens of the South-African Mellivora (M. ratel), as well as in the Vison. Far more characteristic is the upper camassial (PI. VII. figs. 3 & 4). In the Mustelince and in " Promeles " it shows the elongate form and the small anterior talon-cusp. The region of the cheek is more sharply separated than in recent Mustela from the nasal region by a blunt arcuate ridge, and in relation with this the depression in front of the orbits and above the infraorbital foramen is deeper. The anterior and posterior roots of the zygoma rise almost vertically, so that the zygoma is shown to have a highly arcuate form, just as in Mustela. The palate is more prolonged behind the molar series than in the recent species. The under contour of the mandible is slightly more arcuate in the fossil than in M. zibellina and M. martes, and even more than in Mustela foina as described. In all the Melince the carnassial is short and often provided with two or three talon-cusps. W h e n there is only one (Mephitis), this is placed opposite the middle of the blade, and on either side connected by a cingulum with the antero- and the postero- 1 W. T. Blanford, ' The Fauna of British India '-Mammalia, p. 159 (1888). PROC. ZOOL. Soc-1902, VOL. I. No. VIII. 8 |