412 



MEMOIRS OF THE CARNEGIE MUSEUM. 



No. 



<='-^-^ 



3. Rhinoceros (?Diceratherium) oregonensis Marsh," incertce sedis. 



Type. — Penultimate upper molar. Peabody Museum of Natural History 



10,002. 



Horizon. — ("Pliocene deposits of Oregon") Mascal formation. 



Locality. — John Day region, Oregon. 



In reference to this fragment Marsh says : ' ... At the union 

 of the transverse posterior ridge with the outer cusp, there is a 

 deep cavity, nearly circular, and enclosed by a vertical cylinder 

 of enamel. The anterior crest, also, is divided, a strong branch 

 being sent inward and backward from the posterior side into the 

 main transverse valley." 



Whether or not this specimen pertains to a Dicerathere may 

 never be settled. I have recently examined this tooth and may 

 state that it may equally well belong to a middle Miocene Rhino- 

 ceros (Teleoceras) . I cannot now see any reason for regarding this 

 type as anything except of indeterminate value. 



4. Diceratherium (?) truquianum (Cope), inccrtoc sedis. 



Type. — A symphysis of the lower jaws with all the incisors and the posterior 

 portion of the ramus with M2 and M3. American Museum Natural History (Cope 

 Collection) No. 7333. 



Horizon. — Lower John Day, Miocene(?). 



Fig. 7. (?Di- 

 ceraiherium) Rhi- 

 noceros oregonen- 

 sis Marsh. 



M^ X i. 

 After Loomis. 



Fig. 8. Diceratherium truquianum (Cope). No. 733.3, Coll. Am. Mus. Symphysis and portion of left 



ramus. X i. 



In describing an incomplete mandible from the ("Truckee beds"") (Lower 

 John Day) Professor Cope says that the specimen "supports molar, canine 

 [= lateral incisor], and incisor teeth. . . . The crowns of the canines [= lateral 

 incisors] are considerably wider than those of the incisors [= median incisors], 

 but do not project very far beyond them. They are sub-triangular in outline, 



" American .Journal Science, Vol. V, 1873, p. 410. Ibid., Vol. XXVI, 1908, p. 00, Fig. 13. 

 "American Naturalist, Vol. XIII, 1879, p. 333. 



