526 JOSEPH LEE CONDE 
shown by extensive erosion of the Lafayette gravels all over 
the southern states. But a distinctive name was first given it by 
Hershey,’ who called it Ozarkian in commemoration of its work 
in the formation of the remarkable gorges of the region of the 
Ozark Mountains. He, however, fully recognized its importance 
as a time of general uplift and erosion, but regarded it as only 
an episode comparable with the Kansan or Iowan episodes of the 
Glacial epoch. The name was adopted, though somewhat reluc- 
tantly, by McGee (Sci. III, 796, 1896), and its importance more 
fully recognized,’ but he regards it as belonging to the Pliocene 
and not the Quaternary. This point we shall discuss later. A 
little later (Am. Geol. XVII, 389, 1896) Upham also adopts the 
name, and, like Hershey, refers it to the early Quaternary, but 
advances it to a primary division of that period comparable with 
the Glacial. But even yet, it seems to me, its full importance is 
scarcely recognized unless it be by McGee, and its true signifi- 
cance entirely overlooked. Indeed both its importance and its 
significance are brought out in strong relief only by the study of 
its phenomena in the western part of the continent and especially 
in California. 
If with Upham we divide the Quaternary period into three 
epochs, the Ozarkian, the Glacial, and the Champlain, then the 
Ozarkian was by far the longest, in fact, longer than both the 
others put together. Or again, if the Quaternary be divided 
into two epochs, the Ozarkian and the Glacial, the Champlain 
being merged into the Glacial, as is commonly done by Euro- 
pean geologists, then of the two, the Ozarkian is by far— perhaps 
by many times——the longer. In many ways the Ozarkian is 
strongly contrasted with the other epochs of the Quaternary. If, 
for example, we adopt the division into three epochs, these are 
characterized each in its peculiar way ; the first, by elevation; the 
second, by ice accumulation ; the third, by depression ; the first, 
by immense erosion; the second, by glaciation and drift deposit ; 
the third, by stratified deposits in seas and lakes. 
t Science III, 620, 1896. 
2“The reference of the Ozarkian to the Pleistocene would multiply by many 
times the commonly recognized duration of that period.” McGee, Sci. III, 796, 1896. 
