SUBORDER D 



ARTIODACTYLA 



189 



Leptotragulns Scott and Osborn [Parameryx Marsh). Imperfectly known. 

 Uinta and Titanotherium beds. 



Protijlopus Wortman. Roof of skull flat. Muzzle 

 and premaxillary short. Orbits not closed behind. 

 Uinta beds. P. petersoni Wortman. 



Oromeryx Marsh. Uinta beds. Eotylopus Matthew. 

 Oligocene (Titanotherium beds). 



Subfamily 2. Poebrotheriinae Cope. 



Dentition complete, brachyodoiit. Orbits not always dosed 

 behind. Premaxillary and symphysis elongated. Piadius and 

 ulna coalesced. Metapodials distinct. Pes with two digits, 

 the lateral metapodials consisting of proximal vestiges only, 



Fio. 250. 



PoUbrotherium wilsoni Leidy. Oligocene (White River beds), Nebraska. A, Skull and lower jaw. 2/g. 

 B, Fore foot. C, Hind foot, i/s- (After Wortman.) 



separate or fused to median digits. Terminal 

 phalanges hoof-shaped. Oligocene and Lower 

 Miocene ; North America. 



Po'ebrotherium Leidy (Figs. 259, 260, ^). 

 Inferior canine small. Lateral vestigial 

 metatarsals separate. Size about that of a 

 roe deer. White River beds. P. wilsoni 

 Leidy. 



Paratylopus Douglass (Gomphotherium 

 Cope) (Fig. 261). Inferior canine large. 



Fig. 261. 



Fig. 2f 



A, Hind foot of Po'ebrotherium (after' Cope) 



for comparison with B, fore foot of Camclus Paratylopus sternbergi Cope sp. Lower Miocene (John Day 



(after Flower), i/s- beds), Oregon. Skull and lower jaw. 1/4 (After Wortman.) 



