Aiiriferoiis Grovels of the Sierra Xerafhi. — Turner. 371 
Campton Falls. N. H., and lately by Prof. J. F. Kemp* at 
Kennebunkport, Me. Dr. B. J. Harrington,! of the Canadian 
Geological Survey, has found similar dikes near Montreal. 
Others have been described from a locality near Whitehall, 
N. Y.,1 and Proctor, Vt.. as well as from the shores of lake 
T + 7 7 
Champlain, by Prof. J. F. Kemp and the present writer.^ They 
are also known to occur on the shores of other lakes in north- 
ern Vermont and southern Quebec, especially lake Memphre- 
magog, and at Sherbroke, Quebec, a few miles north of this 
lake. 
AURIFEROUSGRAVELSOFTHESlERRANEVADA.il 
By H. \V. Turner, Washington, D. C. 
As may be seen b^'' referring to a paper by Koss E. Browne 
on "The Ancient River Beds of the Forest Hill Divide,"^ and 
another by the writer on^'The Rocks of the Sierra Nevada"** the 
Neocene Auriferous gravels of the Sierra Nevada can be 
divided into two main groups: those of the first period, com- 
posed chietl}^ of white quartz pebbles and light colored clays 
and sands, with minor lava flows of rhyolite; and those of the 
second period, called by Browne the "volcanic period," formed 
during the time of the "volcanic cement" (andesite-tulf) flows. 
The former gravels are free from volcanic pebbles, the latter 
often contain them in abundance. The larger mass of the 
Auriferous gravels belong to the first period. That an era of 
erosion occurred between the deposition of the gravels of the 
first period and those of the second period is abundantly 
proven, and it therefore follows that the fossil remains found 
in the two classes of deposits should indicate some difference 
*J. F. Kemi): Trap dikes near Kennebunkport, Me. Amp:ukan 
Geologist, vol.v, p. 127, March. 1890, 
fDr. H..T. Harrin«,non: Can. (Jeol. Survey, 1877-78, p. 4:!!>. 
:j:.T. F. Kemp and Venion F. Marsters: On certain camptonite ilikes 
near Whitehall. Washinirlon Co., N. Y. 
§. F. Kemp and \. F. Marsters: The trap dikes of lake Chani|ilain. 
U.S. Geol. Survey, j?nll. 107. 
||Published by permission of the Direetur of Ihr l'. S. ( ieujogjcal Sur- 
vey. 
■[Tenth Ann. Rep. State Mineralofjist of California, i)p. 4:{.")-4(m. 
lirowne's third period includes the Pleistocene pravels. 
**Fourteenth Ann. Hep. U. S. Geological Survey, p. 405. 
