—_ 
have not heard of anything in the Sierra Nevada region which 
can be referred to the Iowan or any older glacial epoch. 
The so-called “glacial period” in the California mountains 
occupied the last one-twentieth or perhaps the last one-fiftieth 
of the Glacial period as the term is used in the east and in 
Europe. A large part of the cafion cutting in the Sierra Ne- 
vada region may have been accomplished during the Kansan, 
Illinoian and Iowan glacial epochs and the still longer inter- 
glacial epochs. Certainly, with the steep gradients, the Sierra 
Nevada streams were doing something during the long time 
which elapsed between the Kansan and Wisconsin epochs. I 
should say that probably one-third of the cafion cutting was 
Kansan and later in age. 
I have avoided applying the term Ozarkian in California 
because, the Glacial period being so very imperfectly repre- 
sented here, I could not distinguish the work of the Ozarkian 
from that of later time. The preceding discussion empha- 
sizes the facts that there was a marked uplift of the Sierra 
Nevada province probably at about the opening of the Pleisto- 
cene period; that the exact date, relative to crustal movenients 
in other regions, of the inception of this uplift cannot be es- 
tablished at present; that the elevated condition continued 
through the Glacial period; that no interruption leaving ap- 
preciable effects occurred until near the close of the Glacial 
period ; that it is inadvisable to correlate the canons with any 
event in the geology of the eastern states; that the period of 
cafion cutting on the Pacific coast was a very strongly marked 
one, deserves general recognition and a specific designation ; 
and that the term Sierran as applied to it is very acceptable, 
but its use should be confined to the Pacific coast country. 
Taxonomically, it is apparently almost equivalent to Pleisto- 
cene. 
Berkeley, Calif., Nov. 19, 1901. 
The Term Sierran.—Hershey. 95 
