Marsh Collection, Peabody Museum. 205 



^Jliir other ium bicuspis sp. nov. 



A second species of this genus is indicated by a first lower 

 molar or sectorial tooth, figures 42, 43, of the left side. It is 

 somewhat smaller than this tooth in JE. latidens and differs 

 further from it in the possession of two cusps on the heel 

 instead of one, which gives it a more decidedly basin-shaped 



43 



Figure 42. — Left lower sectorial molar of JElurotherium bicuspis Wortman ; 

 outside view. (Type.) 

 Figure 43. — Crown view of same. 



Both figures are three halves natural size. 



character. Of the two cusps comprising the heel the larger 

 is median and the smaller is external. This species is more 

 closely allied to Palceonichs, in which the heel of the first 

 lower molar is tubercular. 



The principal measurements are as follows : 



Antero-posterior diameter 16'8 mm 



Transverse diameter 8'5 



Height of crown at middle cusp .. 12- 



The specimen was found by L. LaMothe on Henry's Fork, 

 Bridger Basin, Wyoming. 



Discussion. — Doubtless some objection will be raised to the 

 placing of this family in the Carnassidentia, and did we have 

 the genus Palceonictis alone to consider, it could be possibly 

 regarded as a more or less questionable procedure, since the 

 development of the fourth superior premolar and the first 

 inferior molar into highly specialized carnassial teeth, to the 

 exclusion of all the others, had not reached quite that degree 

 of perfection displayed by either the contemporaneous viver- 

 rine or canine phylum ; but at the same time, the tendency in 

 this direction was so clearly evident as to leave no room for 

 doubt that the genus should be arranged with those forms 

 which finally developed the typical sectorial dentition of the 

 modern Carnassidentia. There seems, moreover, to be entire 

 unanimity of opinion that ^Elur other imn is not only a mem- 

 ber of the Palseonictidse, but is the direct descendant of 



