298 KANSAS CITY REVIEW OF SCIENCE. 
The fifth terrace of this Morgantown series mark the height to which the 
pre~glacial valley of the Monongahela was silted up partially or entirely during 
the existence of the glacial dam at Cincinnati, since as already stated, no clay 
beds, rounded boulders or other transported material are ever found above its 
top, but instead only angular fragments of the country rock, and thin coverings 
of surface material which has accumulated in situ. 
Owing to the considerable elevation — 275 feet — of the fifth terrace above 
the present river bed, its deposits are frequently found far inland from the Mon- 
nongahela, on tributary streams. A very extensive deposit of this kind occurs 
on a tributary one mile and a half northeast from Morgantown, and the region, 
which includes three or four square miles, is significantly known as the " flats." 
The elevation of the ''flats" is 275 feet above the river or 1065 ^^^^ above tide.. 
The deposits on this area consist almost entirely of clays and fine sandy material,. 
there being very few boulders intermingled. The depth of the deposit is un- 
known, since a well sunk on the land of Mr. Baker passed through alternate beds- 
of clay, fine sand and muddy trash to a depth of sixty-five feet without reaching 
bed-rock. In some portions of the clays which make up this deposit, the leaves 
of our common forest trees, are found most beautifully preserved. "Whether or 
not they show any variations from the species now growing in that region, the 
writer has not yet had time to determine, but when a larger collection has been 
obtained, this subject will receive the attention that it deserves, since if the date 
of the glacial epoch be very remote, the species must necessarily show some 
divergence from the present flora. 
Of animal remains the only fragment yet discovered in this highest of the 
terraces is the tooth of a mastodon, dug up near Stewartstown, seven miles north- 
east from Morgantown. 
The other tributaries of the Monongahela, on which the writer has noted the 
clay and other deposits of the fifth terrace, are Decker's, Dunkard, Whitely, 
Muddy, and Ten Mile Creeks, and in each case the deposits disappear at the 
same absolute level at which they cease along the river. 
The Great Kanawha River, another principal tributary of the Ohio, draining^ 
a region that was never glaciated, also exhibits water-worn boulder deposits 
which disappear at 200 — 300 feet above the present level of that stream, though 
I have not determined the exact limit. 
The glacial dam at Cincinnati presents a complete explanation for the origin 
of Teazes valley, an ancient, deserted river channel twenty miles long and one 
to two miles wide, which leaves the great Kanawha fifteen miles below Charleston, 
W. Va., at Scany, and passing through Putnam and Cabell Counties, extends to 
the valley of Mud River, a tributary of the Guyandotte which empties into the 
Ohio at Huntington. 
This valley, although having an elevation of 200 feet or more above the 
Kanawha, is filled to a great depth with rounded boulders sandstone, chert, can- 
nel coal, and other trash which has plainly been transported down the Kanawha. 
from above Charleston, so that although it was clearly seen that the water of the 
