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being much lighter in its fossil state than when in the mouth of the living 

 animal. The teeth of this great glacial elephant are quite different and 

 much larger than the mastodon which also existed during the same 

 period. The teeth of this extinct elephant very much resemble the teeth 

 of the elephant of the present day. We have also taken from the drift 

 clays above Alton the teeth and several bones of a huge carnivorous ani- 

 mal allied to the bison, probably the extinct Bos latifrous, the spread of 

 whose horns would make those of a Texas steer seem very small in size. 



It is quite probable that during this period more than one species of 

 horse existed. Bones of extinct horses are quite numerous in the tertiary 

 deposits about the base of the Rocky Mountains. 



In digging a well in Greene county, Illinois, the workmen found at the 

 bottom of the excavation the teeth of an extinct horse somewhat resem- 

 bling those of the present day. We also have seen the fossil tooth of a 

 horse from near Alton. 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 subsidence 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 remarka- 

 ble that with the many fluvatile shells and remains of land animals in the 

 loess we also occasionally find the remains of animals almost wholelv ma- 

 rine. 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 resembling 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 ani- 

 mals 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 county, Ills., the stream cut- 

 ting through an ancient valley filled with drift clays, there is exposed be- 

 neath the drift clays a preglacial soil nearly 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, 



