37 



rated l)y a coiispiouoiis interval as in (he Ibrmer s[)ccini(ni. Tlie lolx's ol' llic 

 second anil third premolars are worn nearly to a level with tlieir l)ase. Tin; 

 outer surtiice of the maxillary, as seen in Fig. G, is defined by an oijliijiir 

 ridge at the nasal border, within which the suture of the premaxillaiy ])ur- 

 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 : 



Lines. 



Space occupied by tlie anterior tln-ee premolars 21 



Autero-posterior diameter of first premolar G^ 



Transverse diameter of first premolar 3;^ 



Autero-posterior diameter of second premolar 7 



Transverse diameter of second premolar G^ 



Autero-posterior diameter of third premolar 8 



Transverse diameter of third premolar 9 



Diameter of fang of canine 8 



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

 various localities in the vicinity of Fort Bridger 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 soutii- 

 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- 

 senteil 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 chaiacter 

 and so nearly in size that the jaw may be regarded as pertaining to the sam(> 

 species. 



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

 additional jM-emolars verging close upon the remains of the canine alveolus, 

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

 Palseosyops is seven. 



The lower molars of Palaeosyops resemble those of Palseotherium and 

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

 arc ])roportionately wider and lower, or appear more robust than in the formei- 

 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 com- 

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



