37 



rated by a conspicuous interval as in the- former specimen. The lobes of the 

 second and third premolars are worn nearly to a level with their base. The 

 outer surface of the maxillary, as seen in Fig. 6, is defined by an oblique 

 ridge at the nasal border, within which the suture of the premaxillary pur- 

 sues its course over the position of the fang of the canine. Just outside of 

 the nasal border the surface of the maxillary is depressed. 

 The measurements of the specimen are as follows : 



Linos. 



Space occupied by tlie anterior three premolars 21 



Anteroposterior diameter of first premolar 6J 



Transverse diameter of first premolar , 3| 



Anteroposterior diameter of second premolar 7 



Transverse diameter of second premolar Of 



Anteroposterior diameter of third premolar 8 



Transverse diameter of third premolar 9 



Diameter of fang of canine S 



Fragments of half a dozen lower jaws referable to Palaeosyops, collected in 

 various localities in the vicinity of Fort Bridget' by Drs. Carter and Corson, 

 have been submitted to my examination. 



A well-preserved specimen, consisting of the greater part of the jaw, was 

 discovered by Dr. Carter imbedded in a greenish gravel thirteen miles south- 

 east of Fort Bridger. The right ramus is represented in Fig. 11, Plate V, and 

 it contains the molars and the back two premolars, which are also repre- 

 sented with a view of the triturating surfaces in Fig. 10 of the same plate. 

 The teeth, corresponding with those in part upon which the species Palceo- 

 syops paludosus was originally indicated, are identical in anatomical character 

 and so nearly in size that the jaw may be regarded as pertaining to the same 

 species. 



In advance of the teeth retained in the jaw there arc indications of two 

 additional premolars verging close upon the remains of the canine alveolus, 

 and thus the specimen shows that the number of the lower molar series of 

 Pakeosyops is seven. 



The lower molars of Palseosyops resemble those of Palasotherium and 

 Anchitherium, but even more closely those of Titanotherium. The crowns 

 are proportionately wider and lower, or appear more robust than in the former 

 genera. 



The crown of the anterior two molars is quadrately oblong oval, with the 

 fore and aft diameter largest and the depth less than the width. It is coin- 

 posed of two divisions or lobes, one in advance of the other. The last molar 



