1084 The Artiodactyla. 
Cervide on the other. The Poébrotheriide have originated, from 
‘some family with diminished lateral digits, perhaps the Dichobuni- 
de, various intermediate genera being yet unknown. They are 
the direct ancestors of the Protolabidide, the camels, and the 
Eschatiid. These relations may be expressed in the following 
e :— 
Bovidæ. Eschatiidæ. 
| 
Cervidæ. Camelidæ. 
Moschidæ. Protolabididæ. 
Tragulidæ. Poëbrotheriidæ. 
Oreodontidæ. 
? * 
Merycopotamide. Ceenotheriide. Suide. 
anion | X a i 
Anoplotheriidze. Anthracotheriids. Dichobunide. Hippopotamidee. 
$ $ 
Pantolestidæ. 
Of PANTOLESTIDÆ but one genus is known. The premolars 
are all simple in the upper jaw, exċept the fourth, which has one 
external and one internal tubercle. Six species are known from 
the Bridger and Wasatch Eoeines of N. America. (Fic. 2.) 
The structure of the premolars in Anoplotherium is complex for 
so primitive a type, and the third superior has an internal crest as 
well developed as in some of the Boöïdæ. To the ANOPLOTHERI- 
.DÆ are referred, besides Anoplotherium, Diplobune of Fraas and 
 Dacrytherium, Mixtotherium and Mixochærus of Filhol. But the 
structure of the feet of the latter genera is unknown. In Mixto- 
therium the fourth premolar is more, and the others less complex 
than in Anoplotherium. (Fres. 1, 3.) f 
The known genera of DicHosunip&® are Dichobune of Cuvier, 
with Spaniotherium and “Dilotherium of Filhol, in which{the inte 
