54 



TRANSACTIONS OF WAGNER 



UINTA SELENODONTS 



The molars' considerably resemble those of Leptoineryx, but the cusps 

 are more conical and less compressed, as well as somewhat smaller, which 

 makes the transverse valleys wider and separates the two external crescents 

 more ; the external cingulum is quite conspicuous. On m^^ is a large fifth 

 cusp, which has a continuous rim enclosing a narrow fossette. 



The 5/&//// (Plate II., fig- 10) is in general appearance and character a good 

 deal like that of Protylopus, but is somewhat heavier and stouter, and the 

 muzzle is more elongate, especially in the anterior region where the diastemata 

 in the dentition occur. The tylopodan characteristic of a triangular skull with 

 its broad cranium and forehead, and slender, tapering muzzle, is very distinctly 

 displayed. The cranium is relatively well-rounded and capacious and the 

 sagittal crest is short, though quite prominent, at least in old individuals, 

 while the temporal ridges are long and converge backward quite gradually 

 into the short crest. This arrangement prolongs the forehead well behind the 

 orbits and gives it much the same shape as in Protylopus, but the temporal 

 ridges are far more prominent than in the latter, and separate the forehead 

 from the brain-case in a more conspicuous way. The orbit is small, with its 



