484 The American Naturalist. [June, 



the metaconid, which is present in the members of the true Equine 



No metapodials of P. javalii have been found associated with the 

 teeth ; however there are in the collection of the Jardin des Plantes 

 and also in the Ecole des Mines, a number of enlarged third metacar- 

 pals and metatarsals from the same beds in which they find the teeth 

 of' P. J uvali, and in all probability belong to this species. As already 

 stated the horse-like skull and teeth of Paloplotherium javalii support 

 the view that this type of cranium belong with these specialized meta- 

 podials. The third metacarpal in r.jnva.lii is long and slender, and has 

 a large facet for the unciform, the section of this bone is triangular 

 with the lateral surfaces very oblique. This structure of the metapo- 

 dial shows that the lateral digits were placed far to the inside and be- 

 hind. The posterior cannon bone is more progressive in its horse-like 

 character than the anterior, the proximal surface is much expanded 

 transversely aud the postero-lateral cavities for the metapodials are 

 placed further behind than in the fore foot. 



M. Filhol has described remains of Paloplotherium minus from the 

 Oligocene of Ronzon, and in these beds they again find the enlarged 

 third metapodials which are so abundant in the Debruge Eocene. 

 This is another proof that the teeth and podial elements in Paloplothe- 

 rium are properly referred. 



A form closely related to the Palatotheridse is the genus Anchilo- 

 phim. This genus is more normal in its tooth structure in comparison 

 with the early horses than Paloplotherium, and is considered by some 

 authors 8 as in the direct line leading to Equus. Kowalevsky 9 however, 

 calls Anchilophus a " Versuchgenus in der Pferderichtung, der Ver- 

 such war aber erfolglos, und der Anchilophus erlischt im Eociin, ohne 

 directe Nachfolger zu hinterlassen." Kowalevsky reached this con- 

 clusion from studying the carpal bones of Anchilophus. I have had 

 access only to the teeth of Anchilophas desmarestii and consequently 

 must base my conclusions upon the characters of one species only of 

 this genus. A comparison of the superior molars of A. deanaret&H with 

 those of Mesohippits, a genus which is considered by all competent 

 authorities to be in the true Equine series, shows the following differ- 

 ences : The ectoloph in both genera has nearly the same form, but in 

 Anchilophus the mesostyle is absent, this is well developed in Mesnhip- 

 pus. In A. desmarestii thehypostyle is wanting, which is so prominent 

 in the molars of Mesohippus. The direction of the metaloph in An- 

 u Pavlow. Bull. 



