STROPHOMENA AND OTHER FOSSILS FROM CIN- 
CINNATIAN AND MOHAWKIAN HORIZONS, CHIEFLY 
IN OHIO, INDIANA, AND KENTUCKY* 
Aug. F. Foerste 
The Stones River, Black River, and Trenton limestones, in 
the area crossed by the Cincinnati geanticline, are essentially 
limestone formations, while the Cincinnatian, including the Rich- 
mond, consists of alternations of thin limestones with variable 
amounts of argillaceous matter. This contrast is . emphasized 
if the Catheys be placed at the base of the Cincinnatian, instead 
of at the top of the Trenton. 
At various periods during the deposition of these strata, argil- 
laceous elements predominated, and during the most important 
of these, judging from the comparative absence of fossils, life 
must have been nearly extinct over areas by no means inconsid- 
erable. These periods of local extinction of life, or the withdrawal 
of life to narrower areas, were followed by others during which 
life spread and again covered more or less of the area from which 
it had retreated. In some cases, the returning life came from a 
source quite different from that to which the former life had 
retreated, so that a relatively new fauna was introduced into the 
territory under consideration. Such a change of faunas gives 
the intervening argillaceous, more or less unfossiliferous strata 
their chief importance from the standpoint of stratigraphical 
geology. 
One of the most important of these comparatively unfossil- 
iferous sections of argillaceous strata is that to which the name 
Paint Lick was applied. This forms the lower part of the Gar- 
rard formation as originally defined by Marius R. Campbell, the 
upper part corresponding to the Mount Hope member of the 
Maysville, stratigraphically . The Paint Lick member of the orig- 
inal Garrard formation may be traced from Bath county south- 
* Published by permission of Professor C. J. Norwood, Director of the Ken- 
tucky Geological Survey. Plates I to VI are the property of the Survey. 
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