Editorial Commont. 
389 
EDITORIAL COMMENT. 
The Ozarkian Epoch. 
A very timely suggestion is made by Mr. Oscar H. Hershey 
in Science for April 24, 1896 (new series, vol. hi, pp. 620-622), 
in proposing that the time of great epeirogenic uplift succeed¬ 
ing the deposition of the Lafayette formation and causing 
extensive erosion of the Lafayette and underlying beds shall 
be named the Ozarkian epoch. This designation comes from 
Mr. Hershey’s studies of the stream sculpture of the Ozark 
plateau, as published in the American Geologist for last 
December (vol. xvi, pp. 338-357). This long and most remark¬ 
able epoch, when the Layfayette uplift of the North American 
continent and of Europe culminated, inaugurating the Ice age, 
had been recognized and definitely noted, as one of the Qua¬ 
ternary series of epochs, in the American Geologist for May, 
1895 (vol. xv, p. 294). The quietude of the Tertiary era in 
eastern North America was followed by a strong contrast in 
the epeirogenic movements of the Lafayette, Glacial, and 
Recent periods. It seems therefore preferable, as in the 
article last cited, to include under the Quaternary era the 
entire Lafayette period, in both its epoch of deposition of the 
Lafayette formation (thought by the present writer to be not 
marine, but fluvial, as the first result and record of the uplift 
at its beginning) and the closely subsequent Ozarkian epoch 
of great elevation and erosion. The extraordinary physical 
changes of the Lafayette, Ozarkian, Glacial, and Champlain 
epochs, together constitute a series so widely dilferent from 
the much longer preceding repose of Tertiary times that they 
seem to be naturally united in the Quaternary era, which 
also reaches on to the present day, unless the Recent period, 
while man’s growing supremacy has modified the earth’s sur¬ 
face by his cultivated fields, villages, and cities, shall be named, 
as by Le Conte, the Psychozoic era. w. u. 
