CLINTON CONGLOMERATES AND WAVE MARKS. 193 
lower more sandy Clinton also thickens eastward. Pebbles were 
found in the Clinton only in Ohio, in Clinton and Highland 
counties, being more frequent in the latter. 
Location of shallow waters as evidenced by pebbles and to a 
certain extent by wave marks.—\n the late Trenton and early Utica 
or ‘‘Lower Hudson,” shallow waters, as evidenced by pebbles 
and wave marks, occurred over the southern Blue Grass counties 
of Kentucky. In the late Utica, shallow water areas extended 
over the entire Blue Grass region of Kentucky as far as the Ohio 
side of this area near Cincinnati. In the early Middle Hudson 
shallow waters are again confined apparently to the southern 
counties, while towards the middle and close of the Upper Hud- 
son, with the exception of Oldham county, the shallow water 
areas extended all along the eastern counties from the most south- 
ern one, Lincoln, as far as the most northern one, Adams, in 
Ohio. This location of shallow water areas in the eastern counties, 
instead of over the entire Blue Grass region during Upper Hudson 
times, will, if substantiated by future investigations, be very sug- 
gestive as to geographical changes during pre-Clinton times. 
In the Oneida and Medina shallow waters again occurred in 
southern counties. But in the Clinton it is again the eastern 
counties, all the way from Clark in Kentucky to Adams in Ohio, 
which give the evidences of shallow waters. 
In the rocks here discussed two kinds of materials occur— 
fossils or their comminuted remains, derived from the animal 
life of the Paleozoic seas of these regions, and detrital materials 
of a foreign nature, derived more or less directly from some land 
area. The detrital beds usuaily increase in thickness going 
southwards, and not infrequently also, though apparently to a 
less marked degree, on going eastward. The explanation for this 
may be that land lay in these two directions, but an equally sug- 
gestive way of stating what perhaps amounts to the same thing, 
is that these detrital remains may have been carried northward 
and westward by some ocean current which found its way north- 
ward along the eastern border of some Palzwozoic continental 
area. 
