4 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
grow along creeks and on hilly places. There are a few white pines 
scattered through the hardwood bushes, and some blocks of fine 
pine timber. Cedar [ Thuja] and hemlock are small and occur 
only along creek bottoms except on the higher ground some miles 
north and west of the town, where they become larger and more 
numerous. North of the town there are extensive birch and cedar 
swamps.” 
Mount Forest. — Mount Forest is 55 miles northwest of Milton. 
Mr. Brooks writes: “ At Mount Forest there are no hickory (except 
a few bitter hickory), walnut nor white oak, but cherry and yellow 
birch occur, both growing very large. There are more swamps and 
evergreen timber than at Milton, and less hard wood, though beech 
and maple grow much larger than they do there. The country 
is rolling and not flat. Hemlock and cedar grow to a large size, 
and in favorable situations there are numerous white spruce, black 
spruce, balsam, and tamarack.” 
Life Zones of Ontario. 
The Province of Ontario extends from the shores of Lake Ontario 
and Lake Erie north to the Albany River and James Bay, a distance 
of more than 600 miles. Within its boundaries are represented 
at least three life zones, the Transition, Canadian, and Hudsonian, 
a brief review of which will aid in understanding the distribution 
of mammals in the Province. The following notes on the char¬ 
acteristics of the life of the Canadian and Hudsonian zones are 
based on my own observations, those on the Transition zone on data 
furnished by Mr. Brooks. 
Transition zone. — The area covered by the Transition zone in 
Ontario extends from near the southern boundary 1 of the Province 
north to the region between Lake Simcoe and Lake Nipissing. 
Among its characteristic trees are beech, red oak, white oak, elm, 
basswood, black walnut, butternut, and at least two species of 
hickory. In suitable places arbor vitae and hemlock occur at least 
as far south as Milton and probably to the southern boundary of the 
Province, while toward the northern limit of the Transition zone 
1 It is probable that enough austral elements occur in the fauna and flora of the north 
shore of Lake Erie to include a narrow belt along the extreme southern border of the 
Province within the limits of the Upper Austral zone (Carolinian fauna). 
