698 THE BRIDGER FAUNA. 



Scientifin Expedition of 1877. As pointed out by Leidy, this genus differs 

 from Palceotherium in the isolation of the internal cones of the superior molars 

 from the external longitudinal crescentoid crests, and in the presence of but 

 one inner tubercle on the last three premolars instead of two. There is but 

 one internal cone on the last superior molar. Formula, I. 3, C. 1, Pm. 4, 

 M. 3. Number of inferior molars similar. Inferior true molars, with four 

 acute tubercles alternating in pairs and connected by oblique crests, which 

 thus form two Vs, with their apices exterior. The last molar adds a fifth 

 posterior tubercle. The last premolar lacks the posterior inner tubercle. 

 The second and third have but one, the outer series of tubercles, and the 

 first is compressed. The canines are separated by a slight interval from 

 the premolars, and are in the continuity .with the incisors. The premaxil- 

 lary bones do not reach posteriorly as far as the nasals. 



The molar characters are generally similar to those of Menodus, but 

 the latter has two internal tubercles of the superior premolars, and only 

 three inferior premolars. 



The species originally named by Leidy Palceosyops pahidosus belongs, 

 according to Marsh, to the succeeding genus, Limnohjiis Leidy. When first 

 described, it was not characterized generically, a brief specific description 

 only being given. He afterward included species of Palceosyops in it, and 

 in so doing first characterized the genus. Hence I agree with him in retain- 

 ing the name Palceosyops for the latter, and not the former, as is done by 

 Marsh. 



My material does not permit me to give a description of all the generic 

 characters, since portions of skeletons in my possession cannot be referred 

 to their species with absolute certainty. Neither Dr. Leidy nor the Prince- 

 ton paleontologists have baen more fortunate, judging from their writings. 

 These authors have, however, described various bones which they believe 

 to pertain to the genus. Neither of them gives the number of the digits, 

 which were probably four in front and three behind. I extract the following 

 observations from the Report of the Princeton Scientific Expedition for 1877. 



"In general features it {Palceosyops major) strongly resembled the tapir, 

 with stout body, slender tail, and very short neck, compensated by a pro- 

 boscis of considerable length. In comparing the heads of the ancient and 



