. Canadian journal of agricultural science. Agricultural Institute of Canada; Agriculture. .^iyyMiMyi. l'l(iM,lpil lioihim lands—Tlio cliiof smiv Fiasei- Valley. fif mri.«!riii!fneq. I' lui-aduw—The breetling- place of Aedes vexans. The Entomological Brancli of the Dominion Depart- ment of Agriculture, in resjionse to a request from the residents of the district, has for the last two years un- dertaken an investigation of the problem. During the first year a faunal survey was made, and, by means of an automobile over two thousand S(|uare miles of terri- tory were scouted for
. Canadian journal of agricultural science. Agricultural Institute of Canada; Agriculture. .^iyyMiMyi. l'l(iM,lpil lioihim lands—Tlio cliiof smiv Fiasei- Valley. fif mri.«!riii!fneq. I' lui-aduw—The breetling- place of Aedes vexans. The Entomological Brancli of the Dominion Depart- ment of Agriculture, in resjionse to a request from the residents of the district, has for the last two years un- dertaken an investigation of the problem. During the first year a faunal survey was made, and, by means of an automobile over two thousand S(|uare miles of terri- tory were scouted for adult and larval mos(|uitoes. The mosquito fauna, consisting of over twenty species, was studied as to abundance, migration, virulence of poison, larval habitats, etc., and the import)ant mos- quitoes were found to be of two species which breed in the low areas bordering the Fraser river, whenever these are flooded by the sjiring freshets. The other species are of slight importance, either because they do not occur very abundantly, or, in some eases, because they have very poorly developed predatory instincts. During the -past season a motor boat and canoe were utilized to make a careful study of the main problem and the work was largely restricted to surveys of the river-flood breeding places. Tjie dominant species in the district is "Affh.'i nl- drichl'' Dyav, a masquito previously known only from Idaho and Montana. The larva was unkno^m until the writer found it last year, and as yet comparatively little is knowni of its life-history. The winter is passed in the egg-stage in the alder-bottom areas bordering the river. At the spring freshets extensive flood-pools are formed in these places and enormous numbers of mosquitoes are produced. The adults are callable of spreading over areas as far as fifteen miles from the breeding places. Although this species bites worst at dusk it is extremely troublesome in sheltered places all through tlie day and it is especially ba
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