Published online by Cambridge University Press: 31 May 2012
In Canada surveys of mosquito populations have been conducted on a scale varying from country-wide programmes to local sunreys about centres of population. The work of the Defence Research Roard and Department of Agriculture in conducting surveys and biological snidies of mosquitoes across northern Canada has been reviewed by Twinn (1950, 1952) and Freeman (1952). During 1944 a country-wide survey, particularly of anopheline species, was conducted as part of a study of possible transmission of malaria (Twinn, 1944). In the Fraser River Valley Hearle (1026) studied the distribution and biology of the mosquitoes of that region. Surveys of a local nature around centres of population have been conducted by McLintock (1944) at Winnipeg, by Urquhart (1948) at Toronto and by Judd (1950) at Hamilton as a basis for control programmes at these centres. During 1952 such a survay, the subject of this paper, was carried out at London, Ontario and its vicinity to determine what species were present in the region, the times of occurrence of larvae and pupae in pools and the seasonal abundance of adults of each species.