Mosquitoes 



condition also in the water, but floating normally at the surface. 

 They pass through several generations in the course of a year, 

 and hibernate as adults. Hibernating mosquitoes may often be 

 found during the winter months in barns and in the cellars and 

 cold garrets of houses or in sheltered places like outhouses and 

 under bridges and stone culverts. In the extreme southern states 

 many mosquitoes are active all through the winter, and mosquito- 

 bars are almost as necessary at Christmas time as during the 

 summer. Even as far north as Baltimore, mosquitoes sometimes 

 bite in houses in December and January. In places where there 

 are prolonged 

 dry spells, and 

 very heavy rains 

 are only ex- 

 pected at certain 

 seasons of the 

 year, adult mos- 

 quitoes live 

 through the dry 

 .spells and lay 

 (heir eggs as 

 soon as the rains 

 come. This is 

 the case in the 

 dry regions of 

 our southwest- 

 ern country, and 

 it is also the 

 case in tropical 

 countries where 

 the entire year is 

 divided into a 

 wet season and 

 a dry season. 



In those countries the wet season is generally considered as 

 comparable to our winter, yet it is the active breeding season 

 of mosquitoes, while the dry season, which is supposed to be 

 comparable to our summer, is the season when the adult mos- 

 quitoes live on and on. With these insects, as with so many 

 others, the life of the adult seems to be dependent only upon 



99 



Fig. 53. — Culex sollicitans : Female showing the 



short palpi which distinguish Culex from Anopheles; 



toothed front tarsal claw at right — enlarged. 



(Author's illustration.) 



