370 LAND MAMMALS IN THE WESTERN HEMISPHERE 



two groups, for of the fachsenodonts, even their most ancient 

 representatives had lost the first premolar, giving the formula 

 pf , while in the fentelodonts it is constantly pf . The fachae- 

 nodonts, which are much less fully known than the fentelo- 

 donts, had teeth very similar in form to those of the latter; 

 and their most conspicuous feature was the shortness of the 

 face and jaws, as contrasted with the extreme elongation of 

 these parts in the fentelodonts, nor did they have the bony 

 flaps under the eyes or the knobs on the lower jaw which gave 

 such a fantastic appearance to the fentelodont skull. Little 

 is known of the skeleton except that there were four functional 

 digits in the manus. The Uinta and Bridger genus {\Achce- 

 nodon) was larger than the Wasatch form {]Parahyus), which 

 was an immigrant, probably from the same region as after- 

 wards sent out the fentelodonts to America and Europe ; this 

 would account for the similarity and probable relationship of 

 the two subfamilies. 



StTBORDER ArTIODACTYLA fPRIMITIVA. fPRIMITIVE 



Artiodactyls 



No doubt, this suborder is an artificial assemblage of unre- 

 lated families, a sort of waste-basket, into which are thrown 

 the groups of which no other disposition can be made in the 

 present state of knowledge. As information becomes more 

 complete, the various families will be redistributed among 

 the groups with which they had a genuine relationship. 



3. ^AnthracotheriidoB. \Anthracotheres 



This family was abundantly represented in Europe from 

 the middle Eocene through the Oligocene, in Asia persisting 

 even into the Pliocene, and were abundant in the Oligocene of 

 Egypt. Migrants from the Old World reached America in 

 White River times, but speedily died out, as they did not sur- 

 vive into the upper Oligocene. The most fully known of these 

 animals is an American species of a European genus \Bothn- 



