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veneer which conforms to the contour of the underlying 

 stratified sands, gravels and clays. These interglacial or 

 interstadial beds are of considerable thickness, and appear 

 to have suffered erosion for a long period of time prior 

 to the deposition of the last till sheet, during which time 

 broad valleys were carved in the earlier deposits. 



The till of the lowei till sheet is generally only exposed 

 in the beds of streams, where it is seen to be composed of 

 hard, compact, sandy clay till, without stratification, 

 containing numerous well polished and striated cobbles 

 and boulders. This till withstands erosion remarkably 

 well, and where trenched by streams is sometimes seen 

 to stand up in vertical sections or to form rock-like ledges 

 which cause rapids. 



Well borings in the district show the presence of a 

 still lower till sheet, but this till is not known to be exposed 

 in any sections. 



Extensive deposits of stratified sands, gravels and 

 lake clays also occur in the district below the level of the 

 Algonquin beach. 



So far as known, no fossils have been obtained in this 

 district from the sands and gravels of the Algonquin beach 

 or from the interglacial beds. Fresh water shells are, 

 however, abundant in the sands and clays of the valley 

 of Nottawasaga river, but at no great height above Georgian 

 bay. 



On the northeastern side of Lake Simcoe an area of 

 drumlins of the long nairow type is well developed. The 

 drumlins are generally composed of a sandy unstratified 

 till or boulder clay which appears to be almost entirely 

 derived from the last till sheet. The longer axes of the 

 drumlins coincide with the di ection of glaciation as shown 

 by striae on adjacent rock surfaces. The general direction 

 of glaciation throughout the district is towards the south- 

 west, and, as a rule, wherever the surface of the rock has 

 been protected from weathering, striae are abundant and 

 well preserved. 



Over a considerable portion of the district around 

 the west and south sides of Lake Simcoe, imperfect drumlin 

 forms are developed, and in fact the greater part of the 

 region appears to have been subjected to some degree of 

 ice moulding beneath the overriding ice of the last sheet. 

 Accordingly terminal moraines or ice marginal deposits 

 are rarely well seen in the district. Some parts of the area, 



