204 THE ICE A(;E in CANADA. 



have, fts yet, al'lorded no maiiiie fossils. I'lof. UelljOf the 

 (U'oloffical Survey, lias, however, found that two hundred 

 miles north of lake Superior the marine de]>osits reajjpear. 

 In the above local details, 1 have yiven merely the facts 

 of greatest im})ortanee, and may refer for many subor- 

 diuate ])oints to the i)apers eataloj^'ued in the introduc- 

 tion to this memoir, and to the reports of the (ieological 

 Survey of Canada. 



IA'.~ Wvsfrni Dinfricfs. 



In the l*rovince (jf Ontario, west of the marine deposits, 

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

 the uppei- and lower drift are developed nuich in the same 

 manner as to the eastward, and contain many travelled 

 boulders from the Laurentian country to the north. The 

 middle I'leistocene 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 noticeil in the secjuel, becoming thus 

 a "forest bed" or interg^acial dei»osit. The plants are of 

 boreal rather than arctic species.* It would thus appear 

 that, in the middle I'leistocene, land and fresh-water con- 

 ditions p>^'evailed in the region of the great lakes. 



I3r. Frank \). Adams has recently made microscoi)ical 

 examinations of specimens of the typical Erie clay from 

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

 debris, 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. 



t Trans. Royal Society of Canada, 1891. 



