Auriferous Gravels of the Sierra Nevada. — Turner. 373 
Mr. J. S. Diller has lately received from Prof. Thomas Con- 
don, of Oregon, some fossil teeth of a horse-like animal, and 
has kindl}^ allowed the writer to insert a note concerning them. 
These remains came from the Ellensburg plant beds and 
hence give additional evidence as to their age. The teeth 
were examined by professors Cope and Lucas, who report 
that they are the "right size and pattern for either llippothe- 
riuia speciosum or //. isosensnm. The former has not been 
found to the northwest and the latter is said to be the com- 
moner species. Both are upper Miocene." 
The lone formation, deposited synchronously with the older 
Auriferous gravels above described, also contains fossil plants 
and other remains, and these can therefore be brought in evi- 
dence as to the age of the gravels. The deposits underlying 
the Oroville table mountain belong to this formation, and 
contain leaves at the Spring Valley hydraulic mine, and also 
at the abandoned Miocene hj^draulic mine in Morris ravine. 
The leaves collected at the former locality by Diller* were 
considered b}^ Prof. Ward to be 3Iiocene or older in age. The 
leaves collected by the writer at the Miocene mine are mostly 
of deciduous trees and are not well preserved. Mr. W. Lind- 
gren has discovered some white fine grained beds on Dry 
slough (Smartsville atlas sheet) about five miles northeast of 
Wheatland, which contain fossil leaves, and the localit}^ is a 
promising one for the future collector. The lone formation 
is best exposed in the area of the Jackson sheet, particularly 
above lone, but although a careful search has been made by 
the writer at many points, no fossil leaves have thus far been 
found in this region that can be determined specifically. In 
Coal mine No. 3, near lone, leaves which Prof. Knowlton con- 
sidered to be probabl}" those of a Sequoia were obtained. Mr. 
Lindgren obtained fossil shells referred by Stearns and Dall 
to the Miocene, from beds in the Marysville buttes, and these 
beds are thought by Lindgren to belong to the lone formation. 
There is still other evidence of the Miocene age of the older 
Auriferous gravels. Underlying the tutfs of the Lassen Peak 
region are a series of light colored lake beds that have been 
*Hiillt'liii 315, V . S. (Jcol()<iical Survey, p. Ki. 
