NATURAL HISTORY, TORONTO REGION
deep water into shoal water near the shore ; towards midsummer they retreat to the deep and cold parts of the lake, where they spend most of their time. In the autumn they again move in towards the shore, seeking their spawning grounds ; these are chiefly rocky reefs and shoals, composed of what is known as honeycomb rock. It is said that gravelly and sandy shoals are sometimes resorted to for spawning purposes, but this is doubtful. Spawning takes place in October and November, and may possibly be extended by some individuals, or under exceptional circumstances, into December; both the time of spawning and of incubation depend largely upon the temperature. The autumn movement commences in September, but does not become general until October; the fish then continue to run in greater or less numbers until the spawning is ended, when they again retire to deep water for the winter. It is a curious fact that even during the spawning season a large number of Whitefish are always to be found in the deep water, but there is no evidence that they ever spawn there.
Cisco. Lake Herring. Argyrosonaus artedi (Lesueur).—The Cisco was formerly common in Lake Ontario. Of late years, however, it has not been taken there in any quantity. Its spawning sea-son is in November and early December.
Long-jaw Herring. Lake Herring. Argyrosomus prognatlrus (H. M. Smith).—This fish may readily be distinguished from any other Whitefish found