378 THE ICE AGE IN NORTH AMERICA. 



alternate beds of clay, line 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 

 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 fragments yet discovered in this 

 highest of the terraces is the tooth of a mastodon, dug up near 

 Stewartstown, seven miles northeast from Morgan town. 



As the relation of this deposit near Morgan to wn to others 

 farther up the river is important, we quote also from the sup- 

 plementary statement of facts made by Professor White in a 

 paper presented at the meeting of the American Association 

 for the Advancement of Science at Buffalo, in 1886 : 



In the region of Morgantown, on the main Monongahela, 

 these terrace deposits end at about 275 feet above low water, 

 or 1,065 feet above tide ; while at Fairmount, twenty -six 

 miles above, there is a vast amount of this terrace material 

 thrown down about the junction of the Valley and West Fork 

 Rivers, and the upper limit of the same is a little over two hun- 

 dred feet above low water, which is here 850 feet above tide. 

 About twenty miles farther up the river (West Fork), near 

 Shinnston, the upper limit of the terrace material is found at 

 160 feet above the water, but here the latter has an elevation 

 of about 885 feet above tide. 



At Clarksburg, where the river unites with Elk Creek, there 

 is a wide stretch of terrace deposits, and the upper limit is there 

 about 1,050 feet above tide, or only 130 feet above low water 

 (920 feet) ; while at Weston, forty miles above (by the river), 

 these deposits cease at seventy feet above low water, which is 

 there 985 feet above tide. It will thus be observed that the 

 upper limit of the deposits retains a practical horizontality 

 from Morgantown to Weston, a distance of one hundred miles, 



