8 Canadian Record of Science. 
stems. The stately elms were in great abundance and of 
remarkable size, attaining occasionally even twenty-five 
feet in circumference, whilst the tulip trees around Niagara 
were not only of considerable height, but were not unfre- 
quently ten to twelve feet through. 
The following plants are characteristic of this group:— 
Liriodendron tulipifera, L. Aster Shortii, Boot. 
Asimina triloba, Dunal. Solidago Riddellii, Frank. 
Nelumbeum luteum, Willd. Coreopsis tripterus, L. 
Corydalis flavula, Raf. Gerardia flava, L. 
Euonymus Americanus,L. Hydrophyllum appendiculatum, Mx. 
Polygala incarnata, L. Phlox subulata, L. 
Agrimonia parviflora, Ait. Sassafras officinale, Nees. 
Cornus florida, L. Morus rubra, L. 
Nyssa multiflora, Wang. Castanea vesca, L. 
St. LAWRENCE GROUP. 
It is a remarkable fact, pointed out by me some years 
ago, that a considerable number of the forest trees of 
Ontario in their range westward, come to an abrupt termin- 
ation in Canada in the district lying between Lake Supe- 
rior and the Lake of the Woods, whilst others are hardly 
seen west of the Sault St. Marie. In Ontario, there are 
sixty-nine species of forest trees, of which thirty-five are 
known either on the north or the south shores of Lake 
Superior. Of these thirty-five, only fourteen cross into the 
prairie region in central and. southern Manitoba. Similar 
ci.cumstances are apparent in an even greater degree among 
the shrubs and herbacvous plants. In Canada, many of 
these seem to be limited in their westward course by the 
outlet of Lake Superior, though in the United States they 
range more or less along the southern shores of that lake. 
The reason of this limit in Canada is readily understood 
when the rocky, hilly nature of the country around the 
northern coasts of Lake Superior and the boreal character 
of the climate there are considered. 
The rough nature of the country immediately to the 
westward of Lake Superior—being successions for over 
three hundred miles of rocky hills, swamps, and large and 
