172 ON THE EXTINCT MAMMALIA OF 



Lines. Lines. 



Breadth of second upper premolar, . . . . 3i 



Width " « « . . . . 2i 



Brefidth of last lower true molar, . ... 4i 



Breadth of second lower true molar, .... 3i 



Breadth of last lower premolar, ..... 3 



CERVID^. 



This family is represented in the pliocene fauna of the Niobrara River by a species 

 of Cervus, the only one of all the ruminants described which does not belong to an 

 extinct genus. 



CERVUS. 



Cervus "Warreni. 



Among the Niobrara fossils collected by Dr. Hayden there are several specimens 

 referable to the genus Cervus, but whether to the same species is uncertain. 



One of the specimens consists of a small antler, represented, of the natural size, in 

 figure 12, plate XXVII. It differs in appearance from the antlers of any species of 

 recent American deer that I have had the opportunity of observing, which led me to 

 refer it to an extinct species. The frontal process is cylindroid, and after rising about 

 half an inch expands in a mushroom-like manner into an annular burr, which is 

 comparatively smooth or devoid of nodular processes. The burr actually looks as if 

 it belonged to and was the termination of the frontal process, and the antler appears 

 to spring from its interior. The antler, after ascending from the burr in a compressed 

 cylindroid manner for about an inch, divides into a pair of diverging fangs or snags. 

 One of these, cylindroid at base, is broken off"; the other is conical, and about two 

 inches and a quarter long. 



A second specimen, with no evidence that it belonged to the same animal as the 

 antler, consists of a jaw fragment containing the lower three molars and the last pre- 

 molar. The teeth agree in form and size with those of the common Deer, Cerous 

 virginianus, and may belong to tliis or to some other recent species. Found as an 

 associate of remains of undoubted exti)ict animals, I have regarded the lower jaw 

 fragment and the antler as representing a peculiar species, for which the name of 

 Cvrvm Warreni has been proposed, in honor of General G. K. Warren, U. S. A., 

 commander of the expedition in which the coUectiDn of Niobrara fossils wa,s made. 



