56 THE ICE AGE IN CANADA. 



to him the boulder-drift is there the upper member of 

 the series. More recently Prof. Newberry has given a 

 summary of the facts in his Eeport of the Geological 

 Survey of Ohio for 1869. From these sources I condense 

 the following statements : 



Tlie lowest member of the western drift, corresponding 

 to the Erie clays of the Canadian Eeport, is very widely 

 distributed, and fills up the old hollows of the country, in 

 some cases being two hundred feet or more in thickness. 

 Toward the north these clays contain boulders and stones, 

 but do not constitute a true boulder-clay. They rest, 

 however, on the glaciated rock surfaces. They have 

 afforded no fossils except drifted vegetable remains, which 

 appear to occur in an " interglacial " or forest bed between 

 lower and upper boulder-deposits. 



Above these clays are sands of variable thickness. 

 They contain beds of gravel, and near the surface teeth 

 of elephants have been found. On the surface are scat- 

 tered boulders and blocks of northern origin, often of 

 great size, and in some cases transported two hundred 

 miles from their original places. More recent than all 

 these deposits are the " Lake Eidges," marking a former 

 extension of the great lakes. 



I believe the Leda clays throughout Canada to consti- 

 tute in the main one contemporaneous formation. Of 

 course, however, it must be admitted that the deposit at 

 the higher levels may have ceased and been laid dry 

 while it was still going on at lower levels nearer the sea, 

 just as a similar deposit still continues in the gulf of St. 

 Lawrence. On the whole, then, while we regard this as 

 one bed, stratigraphically, we may be prepared to find 

 that in the lower levels the upper layers of it may be 

 somewhat more modern than those portions of the 



