NATURAL HISTORY, TORONTO REGION 
broad-leaf component is represented by poplars, and 
they often constitute one-fourth of the forest. 
As has been shown in the article (p. 51) by 
Professor Coleman on the geology of the region, the 
city of Toronto for the most part stands on light 
sandy soils deposited in the Iroquois stage of Lake 
Ontario, and the vegetation is characteristic of such 
soils. The trees are mostly oaks and pines. There 
are, however, patches of heavier soils, and where 
their forest remains it is composed of beech and hem- 
lock, notably in Ashbridge’s woods in the eastern 
part of the city. North of the old Iroquois beach 
the soil gradually becomes heavier, with an increasing 
clay content, and the oak-pine forest is replaced by 
a maple-beech forest. 
On the western edge of the city, in High Park 
and on the Humber plains, the vegetation is dis- 
tinctly Carolinian in its relationships, while on the 
eastern side it is Alleghanian, the city being the 
dividing line between the two types of flora. The 
transition between the two types is very abrupt in 
High Park, where one may pass in a few minutes 
from the Carolinian of the sand plains to the Alle- 
ghanian in the bottom of the deep ravines. 
Toronto and vicinity offer excellent opportunities 
for the study of vegetation in its various habitats; 
in fact there are few places where one can find on so 
small an area so many abrupt changes in the charac- 
ter of vegetation due to variations-in soil and in the 
micro-climatic conditions. One interested in such 
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