The kind and amount of water, as well as the type of container and its 

 location, largely determine the kind of mosquito that will breed in it. 

 Some kinds may breed in salt marshes, the margins of ponds or streams, 

 tree holes, or temporary rain pools, but the domestic mosquitoes prefer 

 water close to man's habitation. 



The house mosquitoes may breed in any place in and about the house 

 w r here water is standing. Unless properly constructed and cared for, 

 cesspools and septic tanks may be sources of prolific breeding, as are barrels 

 containing manure water for watering plants. Goldfish ponds no longer 

 containing fish harbor the domestic mosquitoes. These mosquitoes also 

 breed in water retained in eaves troughs, on flat roofs, in street catch basins 

 and gutters, as well as in ornamental pools and sluggish streams contami- 

 nated with manure or sewage. 



The yellow-fever mosquito prefers clear water. It breeds usually in 

 artificial containers and seldom, if ever, in natural pools. Larvae, or 

 wigglers, may be found in cisterns and in cans, bottles, jars, and other 

 vessels that will hold even a very little water. They may occur in such 

 unexpected places as discarded automobile casings, flower vases, holy-water 

 and baptismal fonts, urns in cemeteries, water pans for chickens, dishes 

 of water under legs of refrigerators, and unused toilet bowls. 



Boat-shaped mass, or raft, of eggs laid directly on water (note reflection) by 

 a northern house mosquito. Enlarged. 



HOW MOSQUITOES DEVELOP 



House mosquitoes usually lay their eggs in boat-shaped masses, or rafts, 

 on the surface of the water. The yellow-fever mosquito, however, lays 

 black eggs on the side of the container, just above the water surface. These 

 eggs may remain viable for some time if they are not moistened. They 

 hatch in a few hours to 2 days after they become wet. 



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