THE GLACIAL PERIOD IN ILLINOIS. 221 
All the remains of the horse we have seen from the 'drift' are of large animals, 
while the majority of the fossil horses from the ' bad lands ' of Dakota are quite 
small. 
"Along the banks of the Mississippi the character of the 'drift' deposits is 
somewhat changed by a sort of lacustrine marly clay left during the slow subsi- 
dence of the waters down the river valley after the ice had melted away. This 
marly clay deposit which caps the river bluffs is called loess and passes gradually 
into the drift clays below. It is somewhat remarkable that with the many fluvia- 
tile shells and remains of land animals in the loess we also occasionally find the 
the remains of animals almost wholly marine. From the loess above Alton a few 
years ago was recovered the skull of a species of walrus with curved tusks down 
from the upper jaw and much resembhng the walrus now inhabiting the Arctic 
seas. From the clays over the quarries at the mouth of the Illinois River we 
have taken the remains of a large and undescribed animal that had apparently 
curved tusks depending from the upper jaw, not unlike the walrus. These tusks 
were some three feet in length, the smooth surface of the ivory being raised 
longitudinally in fluted parallel lines, quite unlike the tusk of any known animal. 
We present portions of these tusks for inspection. Both in the true and modified 
drift we have seen the remains of rodents, some of them small; but one, an extinct 
beaver, was of monstrous size. Some of these animals, from the fact that their 
remains have been found in the mire of swamps, survived the drift period and 
became extinct in later periods. This is especially true of the mastodon. As 
little as is known of the animals of this period, still less is known of the vegetation. 
We also present specimens of wood from the same horizon. 
" At one locality on Otter Creek, in Jersey Co., Illinois, the stream cutting 
through an ancient valley filled with drift-clays, there is exposed beneath the 
drift-clays a pre-glacial soil near four feet in thickness. In this curious deposit 
wood and other vegetation are numerous. A tree lies prone in this soil, with 
parts of the limbs still attached. The trunk of the tree, of which we present a 
section, with portions of the limbs adhering, is flattened and almost turned to 
Hgnite by pressure and lapse of time. But. what is still more interesting are the 
cones or fruit which the tree bore. These cones are about an inch in length and 
somewhat resemble those of a species of conifer, different, however, from any 
known species. We place before you other remains of this ancient vegetation." 
Judge Holmes in commenting upon the specimens stated that marine de- 
posits had been found in a peculiar stratum which was supposed by geologists to 
extend as far south as the mouth of the Ohio River and that the tusks referred to 
in the paper would be a valuable discovery if they proved to be those of a 
walrus. — Globe- Democrat. 
