NATURAL HISTORY, TORONTO REGION 
‘perhaps equally vast gap between the middle of the 
Palaeozoic and the end of the Pliocene is likewise 
without a record. It is probable that during both 
great intervals the region was a land surface under- 
going denudation. What took place during these 
times can only be inferred from the general geologi- 
cal history of North America. 
The different formations within easy reach of 
Toronto will be taken up briefly as given above, 
beginning with the oldest and advancing to the most 
recent. 
ARCHAEAN. 
Archaean rocks are exposed ninety miles to the 
north of Toronto, and may be reached by any of the 
four northward-running railways, the nearest point by 
rail being Washago. After passing the boundary of 
the Archaean the traveller is struck by; the change of 
scenery, rounded hills of reddish gneiss rising irregu- 
larly above valleys generally occupied by a lake; for 
the region stretching two thousand miles to the north 
of the Palaeozoic border is typical “ rocky lake” 
country, with thousands of rock-rimmed bodies of 
water, summer playgrounds for the city dweller and 
tourist. They include the Muskoka lakes and dozens 
of others less known, as well as the eastern shore of 
Georgian Bay. 
At the nearest points to Toronto the Archaean 
consists mainly of Laurentian granite and gneiss, 
with masses'and bands of greenstone or greenschist, 
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