284 THE MOSQUITOES OF NEW JERSEY 



within ten-day periods more than to compensate for evaporation, an 

 enormous number of temporary pools and hitherto empty artificial con- 

 tainers become filled, an enormous increase in water available for mos- 

 quito breeding takes place. It is true that this heavy rainfall will wash 

 breeding out of streams, storm drainage sewers and sanitary sewers but 

 this fails to compensate for the enormous increase in temporary pools 

 and the filling of artificial water containers. 



CONTROL OF UPLAND MOSQUITOES 



With this picture in mind we turn to the consideration of the control 

 of the different groups of fresh water breeding mosquitoes. These 

 groups are, in the order of their importance, the house mosquito group, 

 the swamp mosquito group, the woodland pool mosquito group, and the 

 malarial mosquito group. 



The house mosquito group thrives in the wilds to some extent but is 

 always found in breeding places created by man. The typical species 

 {Culex pipiens) known as the house mosquito, has been called the "mos- 

 quito of civilization" because of its ability to thrive in breeding places 

 created by man. 



No water accumulation is too small and almost no water is too pol- 

 luted with human wastes to breed house mosquitoes. In general pipiens 

 is much more ubiquitous than territans and breeds in wider variety of 

 water accumulations. 



This group overwinters in the adult stage and consequently is 

 greatly reduced in numbers by inclement weather. While normally these 

 species do not show much migratory power, pipiens, when emerging 

 from large breeding places in dense broods, has been proved to move at 

 least two and one-half miles from the place of origin. Such movements 

 are, however, believed to be extraordinary and to occur under special 

 conditions only. 



The problems in the control of the house mosquito group are con- 

 cerned with finding breeding water about human habitations and 

 promptly getting rid of it, or treating with larvicides to destroy all 

 breeding in it. Sewer basins, cesspools, barrels, tubs, pails, and pans 

 are expected breeding places but stopped up rain pipes, tin cans, 

 crockery, furnace humidifiers, pools in cellars or under houses without 

 cellars are often so hidden as not to be detected until emerging mos- 

 quitoes bring about a more thorough search. 



It is significant that Culex pipiens is second in point of numbers in 

 collections made in villages nearby great undrained salt marshes and in 

 those sections of the state where the salt marsh mosquitoes are under 



