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recognize their larvae when they are seen, and to distinguish them 

 from other mosquito larvse ; then a most thorough search for all pos- 

 sible breeding places should be made within a radius of a mile. This 

 distance is mentioned, since it seems rather definitely proven that the 

 Anopheles mosquitoes do not fly for great distances. After the breed- 

 ing places are found they should be drained or filled in Avith earth, or 

 they should be rendered uninhabitable to the Anopheles larvae by cov- 

 ering the surface of the water with a thin film of kerosene oil, or by 

 introducing certain fish which feed upon the larvae, such as top min- 

 nows, sticklebacks, young sunfish, or goldfish. 



Fig. 4. — Eggs of Anopheles. Enlarged (author's illustration). 



Pending the result of such exterminating measures, all houses in 

 malarious localities should be carefully screened to prevent the en- 

 trance of mosquitoes. After screening, thorough search should be 

 made in the house for mosquitoes which have already gained entrance. 

 Such as are found roosting upon the walls should be captured by 

 placing an inverted vial over them, or they may be stupefied by burn- 

 ing a small amount of pyrethrum powder upon a tin dish cover. Per- 

 sons wishing to avoid malaria should not sit out of doors exposed to 



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