396 , NEW YORK STATE MUSEUM 



the Ontario drumlin area, while the lower half of the Brockport, 

 Albion and Medina sheets show the westward termination as far as 

 the drumlin forms are indicated by the map contours [pL 17]. West 

 of the Genesee river and near the Ontario shore distinct drumlins 

 occur, shown in "plate 18, where the Iroquois waters were too deep 

 for effective erosion. Westward, on the Niagara-Genesee prairie, 

 the drumlin forms gradually become very elongated and indefinite 

 low ridges, which slowly change to faint, invisible swells dying out 

 farther west. On the sheets toward Niagara the drumlinized 

 character of the surface is suggested only by the obliqueness of the 

 streams and contours to the general slope [pi. 19]. 



Southeastward the drumlin area terminates in peculiar fashion, 

 forming a decided point at Syracuse. The most easterly drumlins 

 are the conspicuous group southeast of the city of Syracuse, which 

 stand on a base of Salina shales. The map shows no well formed 

 drumlins north of Syracuse, over the Oneida lake depression, nor on 

 the high ground soilth of the Syracuse district. This extension of 

 strong drumlins as a tongue or point into a district otherwise 

 destitute of such forms is a striking and important fact. 



East of Syracuse, as at Fayetteville, Canastota and Oneida, the 

 soft Salina shales which compose the irregular ground surface show 

 no effect of ice rubbing and ^carry only just enough drift to prove 

 the former presence of the ice sheet. The topography is easily 

 mistaken for morainal, but is due to atmospheric erosion. 



Plates 5 to 21 show some groups of drumlins, interesting for 

 either attitude or form, arranged somewhat in geographic order 

 from east to west. The Weedsport [pi. 11], Clyde and Palmyra 

 [pi. 4] sheets show the best display of drumlins, though other sheets 

 exhibit numerous and interesting forms. 



In the zones of wave erosion by the glacial lakes the drumlins 

 were cut or entirely removed. Lakes Warren and Dana were too 

 short-lived in the Ontario basin to do more -destructive work than 

 cutting notches in the drumlins and building the debris into 

 adjoining gravel spits and bars [pi. 17]. The same applies to Lake 

 Iroquois in its great Cayuga-Syracuse embayment, reaching from 

 Sodus to RichlarPd. But along the continuous or maturer shore 

 of Iroquois, extending from Niagara river to Sodus and from Rich- 

 land to Watertown, as well as along the living shore of Ontario, no 

 drumlin has been able to stand up alone against the waves ; 



