EXI^LANATION OF PLATE VII. 



All tbo figiu'cs are of tbo natural size, except Fig. 10, wliicb is retluced to oue-balf the diaui- 

 eter of the original. 



Figs. 1-5. Merycocbcerus rusticus. From specimens obtained on Sweetwater River, Wyoming, by 

 Professor Haydeu's party in 1870. 



Fig. 1. Series of upper molars of tbc right side, viewed on their tritnrating surfaces. The 

 last tooth bad not entirely protruded, and m the lirst ono the median enamel-pits are 

 nearly obliterated. 



Fig. 2. Upper last premolar and molar of the left side, of the temporary series. 



Fig. 3. Upper second and third premolars of the left side, of the permanent scries. The trit- 

 urating surfaces but slightly -worn. 



Pig. 4. Outer view of the same teeth, in a small jaw-fragraeut. 



Fig. 5. Symphysis of the lower jaw, with the four incisors on each .side. 



Fig. fi. Mekycochceiuis pkoprics. First and second upper molars of the right side. From a specimen 

 obtained on the Niobrara River, by Professor Hayden, in 1857. 



Figs. 7-11. Oreodon supercus. From specimei^s discovered in Oregon by the Rev. Thomas Condon. 

 Fig. 7. Last lower molar of the right side, viewed on the triturating surfixco. 

 Fig. 8. First and part of the second molars, from the same jaw-fragment as the preceding 



figure. 

 Fig. 9. The three lower jjremolars of the right side, viewed ou their triturating surfaces. 



From the same specimen as Fig. 16, Plato II. 

 Fig. 10. Upper view of the intermediate portion of the face, one-half the natural size. 

 Fig. 11. View of the inner surface of a lower canine, from the left side of a specimen of a 



jaw, which lies with its outer face imbedded in a hard mass of rock. 



Fig. 12. Oreodon Culbertsoni. A series of upper true molars of the left side. Specimen discovered 



by Mr. Condon on John Day's River, Oregon. 

 Figs. 13, 14. DicoTYi-ES PRI.STIN0S. Specimens in the Condon collection of Oregon fossils. 



Fig. 13. Triturating surface of a lower penultimate molar. 



Fig. 14. Outer view and view of the triturating surface of a lower last molar. _ 

 Fig. 15. Anchithekium Bairdi. An upper right molar. From the Condon collection. 



Figs. 16, 17. ANcniTHERiUM agreste. From a specimen found ou Red Rock Creek, one of the head 

 streams of the Jefferson Fork of the Missouri. Obtained by Professor Hayden in 1871. 



Fig. 16. Lower last premolar and first molar of the left side. Triturating surface much 

 worn. 



Fig. 17. Last molar, from the same specimen of the jaw as the former. 



Figs. 18, 19. Felis ACGUSTU.S. Specimens discovered by Professor Hayden on the Loup Fork of the 

 Niobrara River, Nebraska. 

 Fig. 18. Portion of the right premaxillary, containing the second incisor, viewed in front. 

 Fig. 19. Upper sectorial molar of the left side, viewed externally. 



Fig. 20. Patriofells ulta (?) A premolar, probably of the up^ier jaw. Specimen found by Dr. Carter in 

 the vicinity of Fort Bridger, Wyoming. 



Figs. 21-23. Teeth of a carnivore, undetermiued. Obtained by Professor Haydeu's party on Henry's 

 Fork of Green River, Wyoming. 

 I<'')g. 21. Outer view of the crown of an anterior premolar. Fig. 22. tljiper view of the same. 

 Fig. 23. Outer view of the crown of a eauiue tootli. 



