THE REPTILES OF OHIO 13 



sively in the till plains, but since it is known from only two localities no sig- 

 nificance can be attached to this fact. 



3. The glaciated Allegheny plateau differs from the till plains, and the 

 greater part of the lake plains, in that the underlying rocks are largely shale, 

 sandstone and conglomerate rather than limestone. Hence the water, in gen- 

 eral, is softer and the pH is lower. The unglaciated plateau area also shares 

 these characteristics. 



The glaciated plateau lies chiefly in northeastern Ohio although a long 

 narrow portion of it extends to the southwest almost to the Ohio River. The 

 topography of the area is varied; in some portions there are low rolling hills 

 while in others the relief is more marked. Near Lake Erie there are several 

 broad valleys, formed by postglacial rivers, in which the streams occupying 

 them at present appear trivial. In the northeastern counties small bogs, ponds 

 and lakes are numerous. Some of the streams of the area empty into Lake 

 Erie but drainage is largely to the Ohio River; along the eastern boundary of 

 Ashtabula County the Lake Erie-Ohio River divide approaches to within 

 twenty miles of the Lake. 



Cultivation is less extensive in the glaciated plateau than in the plains 

 areas to the west. The valleys of stronger relief are for the most part well 

 covered with trees, and wood lots are numerous in many places, especially in 

 Geauga County which is noted for its maple syrup production. The area is 

 well settled, however, and contains many large manufacturing centers such as 

 Akron, Canton and Youngstown. 



Particular points of interest include Buckeye Lake, which served as a 

 reservoir for the Ohio and Erie Canal, and the Pymatuning swamp, a small 

 portion of which entered Ohio near Andover, Ashtabula County. This swamp 

 came closer to being a wilderness than any other place in the state, and it was 

 the mecca of Ohio naturalists until the promotion of the Pymatuning Reser- 

 voir caused the complete destruction of the Ohio portion of it. 



The extreme northeastern corner of the state is the only part of Ohio 

 lying in the Transition Zone. Here many northern plants were once numer- 

 ous and some are recorded from nowhere else in the state. Hemlock is com- 

 mon in many places and small stands of white pine and tamarack are still to 

 be found. 



In this corner of the state Storeria occipito-maculata is common, although 

 elsewhere in Ohio it appears to be rare. Probably Clemmys insculpta and 

 Clemmys muhlenbergii occur in this region; they have been found in the adja- 

 cent part of Pennsylvania but repeated search for them in Lake, Geauga and 

 Ashtabula Counties has resulted in failure. 



Eighteen snakes, two lizards and seven turtles, or a total of twenty-seven 

 species, are known from the glaciated plateau. Of this number, however, 

 Sceloporiis undnlatus, Carphophis amoena helenae, Heterodon contortrix, 

 Natrix kirtlandii, Thamnophis hutleri and Agkistrodon mokasen mokasen 

 barely enter the area or are restricted to habitats closely resembling the adja- 

 cent region. Of these, Sceloporiis, Heterodon and Agkiitrodon, which are 



