60 HOUSEHOLD INSECTS 



and breeding places they may wander several hundred 

 yards from their birthplace. 



From the foregoing description of the life history of 

 Culex pipiens we see that three of the stages, egg, larva, 

 and pupa, are passed on or in the water. The life histories 

 of many other mosquitoes have been determined and in 

 every case it has been found that two, at least, of these 

 stages were passed in the water. We conclude, then, that 

 water is necessary for the development and the very exist- 

 ence of mosquitoes. Conversely, we conclude that in an 

 absence of water mosquitoes will not be able to exist. 

 Mosquitoes will not breed in grass unless standing water is 

 present. 



MALARIAL MOSQUITOES (Anopheles) 



There are several kinds or species of malarial mosquitoes 

 in the United States. No one of these has been defi- 

 nitely proven to carry all of the different types of malaria. 

 One of them, however (Anopheles quadrimaculatus,Fig.24), 

 seems to be the most general carrier, for it has been shown 

 to carry at least two types of malaria, the tertian and the 

 quartan. This species is evidently widely distributed 

 in the United States and is probably responsible for the 

 greater part of the dissemination of malaria. The life 

 histories of the species of Anopheles seem to be similar. 

 Like that of Culex pipiens, the life cycle of Anopheles 

 consists of four stages. 



Eggs. The eggs of Anopheles are laid singly and at 

 random on the surface of the water, but naturally run 

 together and cohere in loose irregular groups or strings 

 of from three to a score or more. This is totallv different 



