380 EXTINCT MAMMALIA OF NORTH AMERICA. 



Oreodon major. 



See page 99, PI. VII, Fig. 1 ; VIII, 

 Leidy: Anc. Fauna Neb. 1853, 55, PI. IV, Fig. 6 ; Proc. Ac. Nat. 6c. 1853, 398; 1856, 164; 

 1857, 89. 

 Mauvaises Terres of White River, Dakota. Miocene. 



Oreodon affinis. 



See page 105, PI. IX, Fig. 3. 



Oreodon hybridns. 



See page 105, PI. IX, Fig. 4. 



Oreodon bnllatus. 



See page 106. 



MERYCOCHCERUS. 



MeryooclicBms proprins. 



See page 110, PI. X. 

 Leidy : Proc. Ac. Nat. Sc. 1858, 24. 



From a calcareous grit on the head-waters of the Niobrara, opposite Fort Laramie. 



Miocene. 



MERYCHYUS. 



MeryohyuB elegans. 



See page 118, PI. XI, Figs. 1—11. 



Leidy: Proc. Ac. Nat. Sc. 1858, 24. 

 Sands of the Niobrara River, Nebraska. Pliocene. 



Merychyus medins. 



See page 119, PI. XI, Figs. 12—14. 



Leidy : Proc. Ac. Nat. Sc. 1858, 25. 

 Sands of the Niobrara River, Nebraska. Pliocene. 



Merycliyus major. 



See page 121, PL XI, Figs. 15, 16. 



Leidy : Proc. Ac. Nat. Sc. 1858, 26. 

 Sands of the Niobrara River, Nebraska. Pliocene. 



LEPTAUCHENIA. 



liBptanclienia major. 



See page 124, PI. XII, Figs. 1—5. 

 Leidy : Proc. Ac. Nat. Sc. 1856, 168 ; 1857, 89. 



From a tributary of White River, in the Mauvaises Terres, near Eagle Nest Butte, 

 and from White Earth Creek, another tributary of White River. Miocene. 



