346 
The Ohio Naturalist. 
[Vol. XIV, No. 8, 
Where was the land from which these pebbles came? One 
would be inclined to answer at once, from the west and north 
where older rocks now occur. But this leaves a structural feature 
observed in both conglomerates rather hard to explain. At dif¬ 
ferent points south-east of Wooster, the upper conglomerate is 
found to be cross bedded with bedding planes dipping sharply 
toward the north. In the northwestern part of the Massillon, 
the southwestern part of the Akron, and the eastern part of the 
Medina quadrangles, the lower conglomerate shows conspicuous 
crossbedding, either toward the west or toward the north. It is 
hard to see how this structure can occur in any other way than 
dipping away from a shore, whether produced by stream current 
or undertow from w r aves. If one would assign the structure in 
this case to northward flowing currents along shore, another 
difficulty is met. In the last named region where twenty to thirty 
feet of the conglomerate is exposed in one outcrop, various levels 
of crossbedding occur in different directions varying from west 
to north. This would seem to be more like a delta deposit of a 
stream flowing from the southeast. No case of crossbedding has 
been found which would indicate that the shore was to the west 
or north, but rather to the south and east. If the interpretation 
of this structure be correct, it points to the presence of a land 
mass where we have thought there was open sea. 
The existence of these unconformities in middle Mississippian 
rock would seem to throw light on the time of the very numerous 
small folds found in the Medina quadrangle and only less numerous 
in a number of other quadrangles eastward to the Pennsylvania 
state line. They rarely occur where the Pennsylvanian is exposed 
above, hence the uncertainty of assigning them to that age or 
later. Some of them very likely belong to post Mississippian 
time, but it should be stated that so far as observed they are much 
less numerous in the Pennsylvanian than in the Mississippian and 
particularly in the Mississippian below the conglomerate horizons. 
One very clear case occurs in an outcrop in the north-east comer 
of the Medina quadrangle in a ravine one-half mile southwest 
of Hinckley village, where the horizontal beds of the Sharon 
conglomerate (base of Pennsylvanian) rest upon the upturned 
edges of the Mississippian. The top of the latter here is about 430 
feet above top of the Berea, or more than 150 feet below the hori¬ 
zon of the lower conglomerate. The contact is sharp and the 
layers of shale are inclined about twenty-five degrees. 
If these conglomerates described above are the same beds 
found in the central part of the state and southward, which would 
appear to be true, it implies the presence of associated uncon¬ 
formities wherever they occur. 
