1914] Merriam: Tertiary Mammals from Northeastern Nevada 277 



The little collection from the McKnight locality resembles in gen- 

 eral the fannal stage of the Cedar Mountain beds southeast of Walker 

 Lake. The Cedar Mountain fauna is in general like that of the 

 Mohave, but may be a somewhat earlier stage. The writer 1 has consid- 

 ered the Cedar Mountain fauna as early Upper Miocene. 



The locality at the McKnight Ranch is reported by Professor Jones 

 to be within the limits of the Pliocene as mapped by the Fortieth 

 Parallel Survey of King. It lies approximately in the region from 

 which King 2 described the only Tertiary fauna referred to the Pliocene 

 in the Nevada region. The locality from which the Pliocene fauna 

 is reported by King is described as "Bone Valley, which is drained 

 by the waters of the North Pork of the Humboldt." Mr. S. H. G-ester, 

 who has done extensive geologic work in the Elko region, informs me 

 that while working in this area he learned of an occurrence of fossil 

 bones at a locality known as "Bone Valley," situated within the 

 limits of an area a few miles in diameter, which would include the 

 McKnight locality. 



The fauna listed by King from Bone Valley, Nevada, consisted of 

 Merychippus mirabilis, Protohippus perclitus, and fragments of 

 Cosoryx. The Merychippus of King's report may well coincide with 

 that obtained by Professor Jones and Dr. "West. A worn tooth of 

 Merychippus may easily be confused with Protohippus, as has often 

 occurred. The Cosoryx mentioned by King is synonomous with Mery- 

 codus of the collection submitted by Professor Jones. 



Considering all of the evidence, it seems to the writer probable 

 that the McKnight locality is stratigraphically, if not geographically, 

 the same as King's Bone Valley Pliocene. 



The presumable stratigraphic identity of the Bone Valley Pliocene 

 of King and the McKnight locality, of probable Miocene age, has an 

 important bearing on the Tertiary problem of the middle Nevada 

 region. The age determination of the great extent of deposits in 

 Nevada referred by King to the Pliocene depended to a large extent 

 upon the palaeontologic stage of the Bone Valley collection ; upon the 

 relation of this collection to the Niobrara fauna of the Great Plains 

 area ; and upon correlation with beds in Oregon considered by King, 

 on the authority of 0. C. Marsh, to represent a Pliocene stage. 

 The collections obtained by Professor Jones and by Dr. West from 

 the McKnight locality, as also the material to which reference is made 



1 Merriam, J. C, Vertebrate Fauna of the Cedar Mountain Beds, Univ. Calif. 

 Publ. Bull. Dept. Geol., 1914. In press. 



2 King, C, U. S. Geol. Expl. of 40th Parallel, vol. 1, p. 43^ 1878. 



