Age of the Don River glacial deposits, Toronto, Ontario
Introduction After a preliminary statement of the main facts, the discussion in this paper will relate (1) to the age of the latest glacial deposits at Toronto connected with the existence of the glacial Lake Iroquois, and (2) to the earliest interglacial deposits containing animals and plants which are characteristic of a warmer climate than that which prevails even now north of Lake Ontario. STATEMENT OF FACTS AS TO DATE AND DURATION OF LAKE WARREN The occurrence of warm species of plants and animals in interglacial deposits in the Don River Valley, near Toronto, Ontario, seems at first sight an absolute demonstration of an immense interval of time between the two invasions of glacial ice which are there clearly indicated. Briefly stated, the facts are that in the valley of the Don River and at Scarboro heights near Toronto there is at the base a deposit of till which, after . . .