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UINTA SELENODONTS 



i- 2 and the canine. The crowns are small, laterally compressed and acutely 

 pointed, of a somewhat hastate shape, and very slightly recurved. The canine 

 is very small and looks like one of the incisors, which it resembles in form, 

 exceeding i- 3 - in size hardly more than the latter does i- 2 -. Thus, at a superficial 

 glance, the animal appears to have four upper incisors on each side. The 

 crown of the canine is of somewhat more distinctly hastate shape than that 

 of i- 3 -, expanding below the neck and then tapering to a very acute point; it 

 is also laterally compressed and its edges are trenchant. It is possible that 

 the small size of the canines is a sexual character, and that the two finely pre- 

 served specimens upon which this description is founded are both females, 

 but the analogy of Poebrotherium would lead us to infer that the size of the 

 canines did not differ materially in the two sexes. 



The premolars are small and very simple, increasing in size and complex- 

 ity posteriorly. P 1 , the smallest and simplest of the series, is separated by 

 short spaces from the canine and p- 2 -, which, however, do not deserve the 

 name of diastemata, as they hardly equal the fore-and-aft diameter of the 

 tooth itself. In unworn condition the crown of p J is a simple, compressed 

 cone, without cingulum or basal cusps, elongated antero-posteriorly and ter- 

 minating in an acute point ; the edges are sharp, and, as the front edge is 

 convex and the hinder edge concave, the tooth seems to be somewhat re- 

 curved. P- 2 - is a little larger, but is otherwise very similar, as seen from the 

 outer side ; its transverse diameter is, however, considerably greater and its 

 external face more strongly convex. In some specimens this tooth has no 

 cingulum, but in others the cingulum is indicated on the front and hind 

 edges. P 2 - is separated by a very short space from p 1 and by a still shorter 

 one from p^, while p- and p A are in contact, or may even overlap. P^ resem- 

 bles p 2 -, except for its somewhat larger size, the presence of a faint inner 

 cingulum, and its slightly greater transverse width ; its anterior edge is sud- 

 denly narrowed, so as to become trenchant, making a shallow depression 

 upon the external face, and very feebly marked indications of the basal cusps 

 may be seen. Sometimes the basal cusps, though small, are quite distinct. 

 F- is of nearly the same fore-and-aft length as p 5 , but is decidedly broader, 

 owing to the development of the deuterocone, which, as in the selenodonts 

 generally, is of crescentic form. This inner crescent is much better developed 

 in some individuals than in others, as are also the basal cusps and the ex- 

 ternal cingulum. In the latter case these cusps are not more conspicuous 

 than on p£ while in the former they are much better developed on p*. The 



