The fourth premolar has an oblong square crown with the transverse 

 diameter exceeding that fore and aft, and with the inner part nearly semi- 

 circular. The crown is composed of three lobes, corresponding with the 

 outer pair of the molars, and apparently the large inner one situated opposite 

 the recess of the former. The outer lobes are like those of the molars, with 

 the back one proportionately less well developed, with the outer median but- 

 tress of the crown suppressed, and with the outer median fold of the antero- 

 external lobe more prominent. The inner lobe is a single, broad, undivided 

 cone less prominent but rather larger than the outer ones. It appears to be 

 homologous alone with the anterior of the inner cones of the molars, and at 

 least does not appear to be a connate pair as in the corresponding tooth of 

 Titan otherium. The conspicuous pit in the center of the crown in this 

 genus is absent in Palgeosyops. A thin basal ridge starting in front and back 

 of the internal lobe festoons the crown outwardly and at the bottom externally 

 of the outer lobes. 



The third premolar is a diminished representative of the one behind, but 

 has its antero-external lobe proportionately a little larger, and the postero- 

 external lobe proportionately reduced. The teeth of the two sides are not 

 symmetrical in the specimen. That opposite to the one represented in the 

 figure has its fore part broken away, but the postero-external lobe is consider- 

 ably longer than in the entire tooth. 



The second premolar has a trihedral crown, in which but two lobes are 

 conspicuous. In comparison with the premolars behind, the internal lobe is 

 greatly reduced in size, and the antero-external lobe is much enlarged so as to 

 become the main portion of the crown, while the postero-external lobe is ob- 

 solete. 



The first premolar is a small tooth separated from the others by a slight 

 interval. It has a simple short conical crown with the base slightly extended 

 backward, and is inserted by a pair of fangs. The other premolars and the 

 molars are inserted with three fangs, of which the inner one in the latter 

 teeth consists of a connate pair. 



The canine teeth of Palseosyops were powerful and efficient weapons, and 



resembled those of ordinary carnivores more than they do those of nearly 



allied living animals. Though imperfect in the specimen under consideration, 



the remaining portions, as represented in Figs. 2, 3, Plate IV, indicate teeth 



of the form and proportions of those of living bears. They also appear to 



have nearly the same relative position with the other teeth and the same 

 .5 G 



