66 G. M. DAWSON — GLACIAL DEPOSITS OF SOUTHWESTERN ALBERTA. 



North America. This, with scarcely any doubt, may, from the observa- 

 tions given in this paper, be regarded as that of the maximum of the 

 Cordilleran glacier, and to it I would propose to apply the name of the 

 Albertan stage or formation. 



The Saskatchewan gravels may very possibly represent the Lafayette 

 formation of the eastern states. This correlation has been suggested by 

 Mr Upham, but it is j^rudent as yet to hold it subject to correction, for 

 there appears to be some danger of referring to a single formation various 

 remote gravelly deposits found below boulder-clays. It is, however, 

 maintained by Professor C. H. Hitchcock that the Lafayette represents 

 the earliest epoch of glaciation in eastern America, which in itself ap- 

 pears to give at least some force, with our present information, to the 

 hypothesis that we find the greatest development of glacial agencies at 

 this same time in the maximum spread of the Cordilleran ice-sheet, 

 while only at a later date did the center of ice distribution migrate to 

 the Laurentian plateau. Such a migration must have been in intimate 

 connection with the vast relative changes of level, of which some striking 

 evidence is found in the particular region now under consideration. 



In these later pages of this 2)aper it may be that conjecture has in some 

 instances been pushed too far, but so long as it is understood to be merely 

 a tentative discussion of the facts given, without comment, in the body of 

 the paper, it cannot be misleading. In this southwestern part of Alberta 

 it is at least manifest that the records exist, more or less obscured and 

 interwoven, of a complicated series of conditions during the Glacial 

 period, the final reading of which must add materially to our knowl- 

 edge of the glacial history of the continent as a whole. 



