160 



A Monograph of Culicidae. 



Life-history. — The eggs are laid at the edge of a pool or a 

 moist depression, and remain dormant until covered with water. 

 There are indications that blood food is necessary for develop- 

 ment of the ova. The larvae feed on other mosquito larvae and 

 may become cannibal. In this way it does much good, and 



Fig. 43. 

 Larval mandible of Psorophora ciliata (after Felt). 



Smith states that " its rank as a pest is not sufficiently high to 

 counterbalance the benefits received from it." 



The larvae occur only in temporary pools or pools recently 

 dried out. Those in or at the borders of woodlands are most 







to, ^ 





>J* 



Fig. 44. 

 Comb of Psorophora ciliata (after Felt). 



chosen by them, but they also occur in the open. They may be 

 found in New Jersey from June to August. 



The larva is 10-15 mm. long ; colour pale grey to dark grey, 

 head pale brown blotched with dark brown ; antennae yellowish, 



