204 THE ICE AGE IN CANADA. 



have, as yet, afforded no marine fossils. Prof. Bell, of the 

 Geological Survey, has, however, found that two hundred 

 miles north of lake Superior the marine deposits reappear. 



In the above local details, I have given merely the facts 

 of greatest importance, and may refer for many subor- 

 dinate points to the papers catalogued in the introduc- 

 tion to this memoir, and to the reports of the Geological 

 Survey of Canada. 



IX. Western Districts. 



In the Province of Ontario, west of the marine deposits, 

 which may be roughly stated to extend as far as Kingston, 

 the upper and lower drift are developed much in the same 

 manner as to the eastward, and contain many travelled 

 boulders from the Laurentian country to the north. The 

 middle Pleistocene deposit, however, corresponding to the 

 Leda clay, and the greater part of which has been desig- 

 nated the Erie clay, is not only destitute of marine fossils, 

 but contains so little protoxide of iron that when burned it 

 does not assume a red colour, and it also contains fossil 

 plants, which will be noticed in the sequel, becoming thus 

 a " forest bed " or interglacial deposit. The plants are of 

 boreal rather than arctic species.* It would thus appear 

 that, in the middle Pleistocene, land and fresh-water con- 

 ditions prevailed in the region of the great lakes. 



Dr. Frank D. Adams has recently made microscopical 

 examinations of specimens of the typical Erie clay from 

 the St. Clair tunnel, where it appears to be composed of 

 dtbris, both from the Laurentian cystalline rocks and the 

 Erian beds of the district, f 



* Dawson and Penhallow, Pleistocene Flora of Canada, Bui. Am. 

 Geological Society, 1890 ; Hinde, Interglacial Beds, Canadian 

 Journal, 1877. 



f Trans. Royal Society of Canada, 1891. 



