9602 Ci The American Naturalist. [October, 
64,000 years ago, and that for several thousands cf years before 
the birth of the river there was open water far northeastward 
of the river. Some writers think that the St. Lawrence Valley 
was obstructed by ice until a late date. This is a question to 
be determined; but however it may be, there has been free 
communication for the drainage of the Ontario basin for at 
least 14,000 years. Whether the end of the Ice Age were 
60,000 or 14,000 years ago, all glacial obstructions had re- 
treated to at least from 400 to 600 miles to the north and east 
of the Great Lakes fifty milleniumsago. The lake region was 
roamed over by mastodons, elks and beavers, but we do not 
know of the presence of man. If such be found, anthropolo- 
gists will have all of these years to consider in fixing the an- 
tiquity of man. The story of Niagara River forms an interest- 
ing chapter in the physical growth of the lakes, and gives us 
an approximate idea of the duration of the lake epoch which 
was characterized by the last touches in the fashioning of the 
continent, and fixes the height of the Ice Age a very long time 
ago. 
One point more should be noticed. An error has prevailed 
for fifty years in that it was supposed that the ancient Niagara 
drainage was by way of the Whirlpool, (St. David’s) Ravine. 
This has been found erroneous, owing to the occurrence of rock 
across the Whirlpool Ravine at an elevation of about 170 
feet above the surface of Lake Ontario. 
+ AOS ion cs Te TEL Md 
