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University of California Publications in Geology [Vol. 8 



were carefully examined by Professor Jones, who has kindly furnished 

 the following discussion of the locality : 



The deposit of Tertiary sediments from which the bones were taken is 

 located on the North Fork of the Humboldt Eiver about forty miles northeast 

 of Elko, near the ranch of George McKnight. The area is included in the beds 

 mapped as Pliocene by the Fortieth Parallel Survey. As noted on their map, 

 these beds cover a wide area in the Elko region. 



The bed from which the dark-colored Tertiary bones were taken is a lense 

 of yellow silt showing no signs of stratification and about fifty feet in thickness, 

 lying a short distance above a flow of basic andesite. Both silt beds and basalt 

 dip about twenty degrees to the southwest and the silt projects in two or three 

 small knolls from the face of the hill. The bones are very soft in the damp 

 silt, but on weathering out seem to harden so that they may be safely handled. 

 It will be very difficult to dig the bones from the silt without taking special 

 precautions to preserve them. They are in a fragmentary condition in the silt, 

 and it does not seem likely that a complete skeleton or even a skull will be 

 found in this particular deposit. 



There are at least two igneous flows at this locality, a rhyolite and an ande- 

 site, together with local lenses of tuff. By tracing them out it may be possible 

 to understand the structure and correlation of the lake beds. 



Professor Jones noted also the presence of beds of apparent Pleis- 

 tocene age in the region of the North Fork of the Humboldt, and 

 within the area mapped as Pliocene by the King Survey. 



COMPOSITION AND EELATIONSHIPS OF THE FAUNA 

 The total faunal representation from the Tertiary beds at the 

 McKnight locality includes four forms, of which only one, the Mery- 

 chippus, might permit specific determination. The list of forms recog- 

 nized is as follows : 



Meryehippus, sp., near isonesus (Cope). Camelid, sp. 



Merycodus?, sp. Carnivore fragment. 



The collection as a whole suggests a faunal stage certainly not 

 older than the Middle Miocene of the Virgin Valley or Mascall. and 

 probably not younger than the Upper Miocene Mohave beds. This 

 assemblage represents a stage more primitive than that of the Ricardo 

 Pliocene, which is the next faunal stage known after the Mohave in 

 the Great Basin. Forms like those found at the McKnight locality 

 have been reported from the Snake Creek Pliocene of the Great Plains 

 region, but they are there associated with much more advanced types. 

 A collection from a horizon with a fauna containing only a small 

 percentage of primitive forms would probably not consist solely of 

 the simpler types without those of more advanced stages. 



