DIPTERA. 



199 



shorter life than do the females ; some have little-developed 

 mouth parts and presumably eat nothing at all. 



As to the hibernation of mosquitoes, some species 

 pass the winter in the adult stage, other species in the 

 egg stage, and still others as larvas ; none is actually known 

 to winter over in the pupal stage. Observations show 

 that mosquito larvae are strongly resistant to cold, some 



Fig. 84. — Antennje of mosquito, Culex pipiens: A, male, B, female. (Folsom.) 



being able to freeze repeatedly and yet survive. The 

 larvas live mainly on decajdng vegetable matter and 

 living algae; though some of them are carnivorous, eating 

 other animals in the pond, smaller than themselves. 

 Practically all mosquito breeding goes on in waters where 

 there are no fish; as the mosquito mother, probably 

 obeying the self-preservative tendency of its ancestors 

 to lay its eggs in situations as free from dangers as 

 possible, usually deposits its eggs in some pond or stagnant 

 pool. One species of Culex prefers to deposit its eggs in 



