74 Circular N 0. 15. .
oil on the water in buckets and barrels will destroy the yellow
fever and brown mosquitoes. Draining swampy ground near
  dwellings will reduce the numbers of malaria mosquitoes. Oil
V may sometimes be used on ponds for the latter. Screens on doors
and windows are necessary in both city and country if we would
enjoy freedom from both mosquitoes and house-flies. The dis-
covery that such diseases as typhoid fever and malaria are ear-
ried by these insects makes these effective barriers almost a
i necessity.
~ When mosquitoes have already gained access to rooms it is
. sometimes necessary to adopt other measures to get rid of them.
” ` Insect powder answers this purpose very well, being effective
I V either when puffed freely into a room, or better, to avoid the
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Fm. 11. Adult malaria mosquito (A. maculipennis). Female. Original