CLINTON CONGLOMERATES AND WAVE MARKS. 53 
cinnati group forms, which had been found. The pebbles of the 
conglomerate fragments collected by Professor Orton, were 
unfossiliferous, though fossils have been found recently, as 
described below. The lithological appearance of the pebbles 
was unlike that of any of the limestones known from the upper 
part of the Cincinnati group in Ohio. 
It seemed therefore that some of the statements made in the 
original publication needed re-investigation, before they could be 
considered a safe basis for conclusions as to the probable physical 
and geographical conditions which obtained in Clinton times. A 
week was therefore spent in Clinton, Highland, and Adams 
counties, and sufficient material was found to disprove some of 
the original statements and to shed quite an additional amount 
of light upon the problems involved. 
The original material is given in the following pages in full. 
Abstracts of pertinent observations made by other writers are 
also presented. Those who are more interested in the con- 
clusions at which we have arrived, than in the facts upon which 
the conclusions are based, will find the former concisely 
presented: ac thesend (of this article: 
PEBBLES AND WAVE MARKS IN THE CINCINNATI GROUP. 
Observations of the Kentucky Survey.—In order to understand 
the physical conditions which prevailed during the Clinton 
epoch in Ohio, it is necessary to study this problem in connec- 
tion with conditions existing both before and after this epoch. 
Since the central counties of Kentucky are also involved in the 
Cincinnati anticlinal axis, any facts which they afford will also 
be of interest. The following facts are collated from the more 
recently published reports on the geology of the various counties. 
With the exception of the report on Marion county, by W. T. 
Knott, and that on Clinton county, by R. H. Loughridge, these 
reports are all from the pen of W. M. Linney. 
Trenton In Garrard county some of the layers are very 
irregular in their bedding, and some show wave marks. In 
Clark county the irregular stratification sometimes amounts to 
