GLACIAL WATERS IN THE LAKE ERIE BASIN 35 



ing the rate of recession of the ice front, which was doubtless very- 

 variable.) As the ice front retreated northward the smaller primi- 

 tive lakes blended together arid the higher passes of overflow were 

 abandoned for lower, until finally only one channel persisted in 

 each large basin. The early lakes in the eastern part of the Catta- 

 raugus basin overflowed to the Genesee glacial waters, and finally 

 out to either the Allegany or the Susquehanna drainage; while 

 those in the south side of the basin all overflowed to the Allegany. 



The main branch of the Cattaraugus rises in Wyoming county in 

 the towns of Java, Arcade and Freedom and flows westward, being 

 joined above Gowanda by the south branch. In the eastern part 

 of the basin the lowest escape seems to have been at Machias, where 

 a large stream-cut valley occurs at altitude of 1646 feet, by the 

 Pennsylvania Railroad levels. The first of the larger lakes in the 

 Cattaraugus basin, which we may call the Machias stage, overflowed 

 for ages through this great outlet to Ischua creek and the Allegany 

 river. 



With further recession of the ice front a lower escape was uncovered 

 a few miles south of Gowanda, by the south branch of the Catta- 

 raugus, described as the Persia outlet on page 17. The opening of 

 this outlet lowered the waters more than 300 feet and inaugurated 

 the second Cattaraugus lake, which we will call the Persia stage. 

 This level seems to have been held until lower escape was permitted 

 on the slope west of Gowanda in the vicinity of Perry sburg, as de- 

 scribed on page 22. 



Throughout the Cattaraugus basin there will be found in the 

 higher valleys many small stretches of level silts or sands which are 

 delta fillings made by side streams pouring into the Cattaraugus 

 lakes. These may lie at various levels, but the stronger or more 

 extended fillings will be found to correlate with the Machias and 

 Persia stages, as these were stable for longer time. These deltas 

 should occur at about 1650 down to 1630 feet, and at about 1320 

 down to 1300 feet. Probably some of the villages in the basin have 

 their sites determined by these level areas of gravel or sand, and 

 these will most likely correspond to one or the other of the levels 

 noted above. The lower water levels at Gowanda belong with the 

 second class of glacial lakes [see p. 41]. 



Local lakes must have existed in the basins of the several parallel 

 creeks lying in Erie and Wyoming counties north of the Cattaraugus 

 basin, and now flowing northwest. We will not describe these 

 lakes, but will simply name them in succession from west to east, 

 as follows : In Erie county the New Oregon-Clarksburg lake occupied 



