286 THE WASATCH AND BKIDGER FAUN^. 



tion, the right angle being the antero-extemal. The antero-posterior cutting- 

 edge consists of two cus})s in the middle and a short blade at the posterior 

 angle of the crown. The internal angle supports a cusp. The last premolar 

 has a trilobate section at the base, and supports a median subconic cusp, a 

 short posterior blade, and an internal tubercle. The second premolar is 

 compressed without internal heel, and nitli a rudimental posterior one. 

 (The first premolar is two-rooted in S. caylusi and S. Mans.) 



The species of StypoIo2)hus o( which I have obtained the best preserved 

 remains is the S. viverrintis, an animal about the size of a domestic cat, from 

 the Wasatch beds of New Mexico. Its mandibular bones and teeth are 

 unknown, but I have derived from it the characters of the dentition of the 

 maxillary bone, as above stated. The maxillary teeth of the S. muUicusi)is 

 and S. aculeatus are similar in generic characters, and of these species I 

 know almost the entire dentition of the lower jaw. The posterior part of 

 the cranium of S. viverrintis displays a low sagittal crest. The supraocci- 

 pital bone has a moderate extent on the upper surface of the cranium, 

 supporting part of the sagittal crest, as well as the prominent oblique ones 

 of the inion. The front is rather wide, and tlie nasal bones are flat, and 

 but little naiTOwed posteriorly. The lachrymal foramen is large, and 

 entirely within the prominent anterior margin of the orbit; it is of a verti- 

 cally oval form. A suture extends from it postero-externally to the rim of 

 the orbit, and then returns forward and upward on the facial surface, inclos- 

 ing what I suppose to be the lachrymal bone. On cleaning the surface, I 

 cannot trace any lachrymal bone posterior to the foramen, as is usual in 

 Carnivora {Canis, Felis), and must therefore suppose that this genus pre- 

 sents an external and anterior position of the lachrymal bone, as in Ungu- 

 lates. The evidence of this arrangement is seen on both sides of the head. 

 The foramen infraorbitato is large, and issues above the third premolar. 



The characters presented by the vertebrae are those of the Creodonta 

 in general, with the following moditications: A cervical is of medium length, 

 possesses a hypapophysial heel, which is produced downwards behind, and 

 has but little trace of a neural spine. The neural arch is wide and flat 

 above, and it is pierced on each side by a foramen not far from the lateral 

 border. Two anterior lumbars from just behind the flying ribs, have no 



