21 S 



A third specimen, from John Day's River, represented in Fig. 4, Plate II, 

 consists of the greater portion of* the crown of an anterior premolar. Il is 



blunted at the apex as the result of wear. When perfect and unworn it has 

 measured about 1^ inches in length, about 16 lines antero-posteriorly, and 

 about 9i lines in thickness. 



It is not improbable that part or the whole of the specimens pertain to the 

 species named Elotherium superbum, from an isolated incisor tooth found in 

 Calaveras County, California, in the same formation in which was discovered 

 the specimen of a lower jaw referred to Rhinoceros hesperius. 



Solidungula. 



ANCHITHERIUM. 



Anchitheeium Baiedi. 



The extinct genus of solidungulate animals, Anchitherium, was • originally 

 described from remains found in the middle Tertiary formation of France. 

 Abundant remains of a species have also been found in the Mauvaises Terres 

 of White River, Dakota, which have been described under the name of 

 Anchitherium Bairdi. The Condon collection contains several specimens, 

 consisting of detached molars and fragments of others, apparently of the 

 same species. One of the best preserved of these, the crown of an upper 

 molar, is represented in Fig. 15, Plate VII. In every respect it agrees with 

 the upper molars of the Anchitherium Bairdi of White River. 



Anchitheeium Condoni. 



A specimen in the Oregon collection of fossils, consisting of a small jaw- 

 fragment with a mutilated molar, represented in Fig. 5, Plate II, I have 

 referred to a species of Anchitherium, though several points lead me to sus- 

 pect' that it may belong' to a different though closely allied genus. The gen- 

 eral form and construction of the teeth are the same as in A. aurelianense and 

 A. Bairdi. The intermediate lobes of the crown are proportionately larger, 

 more distinct from the others, and more prominent than in the species just 

 mentioned. A tubercle springing from the basal ridge between the antero- 

 internal and antero-median lobes is obsolete in the true Anchitherium. 



The diameter of the crown in both directions is about three-fourths of an 

 inch. The species was named in compliment to the Rev. Thomas Condon, 



