26 TRANSACTIONS OF THE CANADIAN INSTITUTE. [Vo.. VIII. 
Erie Group.—Including the large number of middle temperate 
plants found in the south-western peninsula of Ontario, and common 
to that area and to South-western New York, and to Ohio, Pennsylvania 
and other Middle States of the Union, whilst some come from farther 
south. 
St. Lawrence Group.—Embracing numerous species distributed 
generally throughout the St. Lawrence valley and lake region, but not 
ranging west of the wooded country immediately beyond Lake Superior 
and Lake-of-the-Woods. : 
Boreal Group.—Including in this those northern species which occur 
on the mountains and near the shores of the Lower St. Lawrence,.around 
the northern coasts of Lake Superior and among the mountains of British 
Columbia. They generally occur where cold and deep waters of the 
sea or lakes or sufficient altitude supply a moderately low temperature. 
Ontario Group.—Representing a considerable class having its max-* 
imum development in Canada in the central and eastern portions of the 
Province of Ontario, but also occurring in the eastern and middle sec- 
tions of the Province of Quebec, and southward in the New England 
and Middle States. 
Prairie Group.—Embracing species familiar more or less over the 
whole of the prairies of Manitoba and north-westward, but probably 
of limited range over the dry prairies of the western and south-western 
sections of Assiniboia. 
Western Plains Group.—Including species belonging to the dry 
prairies and plains of the North-West Territories where the rain fall is 
limited, and extending almost to the foothills of the Rocky Mountains. 
In British Columbia in the valleys of the Fraser and Thompson Rivers 
north of Lytton onward to about latitude 53°, and again in the districts 
surrounding Okanagan Lake and to some extent in the Eastern Kootenay 
and Upper Columbia River districts the precipitation is deficient and 
the dry country plants again appear. 
Rocky Mountain Group.—Embracing the numerous plants, not 
alpine, which in our present knowledge of their range are confined to 
the valleys and foothills of the Rocky and the Selkirk Mountains. 
British Columbia Group.—Comprehending all those species which 
are distributed somewhat generally over, but confined to, the middle 
and southern sections of the Province of British Columbia. 
Southern British Columbia Group.—Including under this the more 
southern plants found in British Columbia, and whose range northward, 
from Montana, Idaho and Washington Territory, has been facilitated in 
some cases by the drier climate of the interior and in others by the gen- 
eral direction of the valleys in the Rocky, Selkirk and other mountain 
ranges there. 
