ORDINAL TYI'KS OF MOLARS: CARNIVO1IA 



135 





FIG. 90. Skull (partial) and dentition of Palaxmictis occidentalis, a, short-faced Creodont from 

 the Wasatch Formation, Lower Eocene. 1. Side view (xp, showing enlargement and sectorial 



modification of p*, ml (x). 2. Front view (xi). 3. Palatal view, upper jaw (x-i), showing 

 tritubercular molars, sectorial modification of the posterior side of jj4, mi, reduction of //(-. 

 4. Internal view, upper and lower teeth, .showing sectorial modification of /<, ml, and MI, m.,. 

 i. Superior view of lower teeth, showing tuberculosectorial character uf /,, m%. 



Evolution of Carnassial Teeth in Creodonta and Fissipedia. 



1. Lover Carnassials in Fix*ij>i-</i. 



In order to thoroughly grasp the principles of transformation of a 

 trituhercular into a sectorial type, let us first examine such a series 

 of the lower teeth as are represented in Fig. 95. 1 In A and B 

 we see the external and internal aspects of the tuberculo-sectorial 



1 From Osborn and Wortman, " Foss. Mamm. Wasatch and Wind River Beds/' 

 Hull. Amer. Mus. Nat. His/., 1892, p. 99. 



