14 Proceedings of the Ohio State Academy of Science. 



to the east at that time. There were, however, numerous large 

 and small shallow depressions formed by the unequal deposition 

 of the drift in the till plain which were at first shallow lakes and 

 later became swamps. 



SURVEY OF THE SHORES. 



With the exception of the portion occupied by the levee, 

 the shores of the present lake are generally low and are bordered 

 by a more or less extensive swamp vegetation. 



The levee extends along the north shore from the park 

 westward and completely around the western end of the lake. It 

 is interrupted only at the waste weir. The face of the embank- 

 ment is of rock with clay above and much of this has been re- 

 cently cemented. The summit is from 4-6 feet wide and clay 

 covered. The steep slope and the firmly packed clay ofl:'er xero- 

 phytic conditions to plants whose root systems are not deep, and 

 distinctly mesophytic conditions to those whose roots strike deep 

 enough to reach the water level of the lake. The center of the 

 levee is used as the pathway to the cottages bordering the north 

 shore. Along both edges is a more or less interrupted line of 

 trees, consisting of Salix nigra, S. alba, Ulmus americana, Acer 

 rubrum, A. saccharinum, Prunus serotina, Quercus imbricaria, 

 Q. rubra, O. palustris, Q. bicolor, Populus deltoides, Platanus 

 occidentalis, Celtis occidentalis, besides the few apple and peach 

 trees which have been planted near cottages. The trees were 

 formerly much more dense than they now are ; but many have 

 been cut down to make way for cottages. There are scarcely 

 any shrubs, an occasional Sambucus canadensis and Vitis aesti- 

 valis along the outer margin is all that is left of the shrub zone. 

 The herbs are but few, only those which can endure strong light 

 exposure and dry soil as Luctuca scariola, Ambrosia trifida and 

 A. artemisiifolia, Oxalis stricta, Erigeron annuus, Anthemis 

 cotula, Achillea millefolium. Polygonum persicaria and P. penn- 

 sylvanica. 



The outer slope of the embankment is also generally steep. 

 It is in some places grass covered and in others bears trees. 



