338 



EtePOKT — 1900. 



loha, Quercus ohlongifolia, Asimina triloba, Chamaecyparis Sphaeroided, 

 and Fraxinus quadrangulata points without question to the pi'evalence of 

 a much warmer climate than now prevails, while, on the other hand, the 

 equally abundant occurrence of boreal types at Scarborough points to 

 the existence of a colder climate at the time these deposits were laid 

 down. It is therefore clear that in the region of Toronto during Pleisto- 

 cene time there were at least two distinct periods, characterised, on the 

 one hand, by a climate equivalent to that of the middle United States at 

 the present day, and, on the other hand, a climate equivalent to that of 

 northern Quebec and Labrador. According to stratigraphical evidence 

 obtained by Professor Coleman, these changes followed the recession of 

 the ice sheet in the or-der given, from which we are to conclude that the 

 climate of the Don Valley is now intermediate between that of the first 

 and second periods, approaching the former. 



On the other hand, again, the flora of Green's Creek and Besserer's, 

 as also that of Montreal, is practically identical with that now existing in 

 the same localities. It thus represents a climate colder than that of the 

 Don period, but somewhat warmer than that of the Scarborough period, but 

 present evidence does not enable us to ascertain if these deposits were 

 laid down before or after the Scarborough deposits. The following sum- 

 mary will probably assist iu conveying a clearer idea of the distinctive 

 dififerences in the vegetation of these three periods. 



Abies balsamea 



Acer pleistocenicum . 



Acer saccharinum 



Acer spicatum . 



Algae sp. . . . • 



AIqus sp. . 



Asimina triloba . 



Betula lutea 



Brasena peltata . 



Bromus ciliatus . 



Carex aquatilis . 



„ magellanica 



„ reticulata 

 Cara alba . . • • 

 Chamaecyparis sphaeroidea 

 Crataegus punc ata . 

 Cyperaceae sp. . • 

 Drosera rotundifolia . 

 Elodea canadensis 

 Encyonema prostratum 

 Equisetum limosum . 

 „ scirpoides . 



sp. . 

 „ sylvaticum 



Eriocanlon sp. 

 Fontinalis sp. 



