274 THE MAMMALIA. 



And in the present case we have only to deal 

 with an established fact, that the Vwerra are the 

 descendants of the Viverrine Dog, CyniHlicti*. 

 There can be no dispute about this. Hereupon 

 commences a new series of modifications, and from 

 the Viverrae are descended the Weasels. 



We now pass from the Upper Eocene of the 

 phosphate of Quercy to a somewhat later period, 

 which produced the Lower Miocene deposits of 

 Saint Gerard le Puy, on the Allier. Here is found 

 the Plesictis, a carnivorous animal distinguished 

 from the Viverrae mainly by the form of its head. 

 Filhol points out that a ' comb ' (crista) of the 

 sagittal suture not previously existing, has been 

 formed by a contracting of the temporal ' combs ' 

 of the Cynodictis; in other words, that we 

 have the perfectly justifiable conclusion that 

 smaller species of Cynodictis passed over into the 

 form of Plesictis under the influence of natural 

 causes. 



In the races directly descended from Cynodictis 

 a change takes place in the nature of the teeth, and 

 the dentition assumes more and more the character 

 of that of the weasel, while, on the other hand, the 

 peculiarities of the Viverree disappear ; thus the line 

 Plesictis Stenoplesictis Palceoprionodon leads in 



