286 THE MOSQUITOES OF NEW JERSEY 



pool group produces only one big brood a year. Hence, if the pools of 

 an area are treated in the spring and breeding destroyed, further work 

 against them is unnecessary for that season. Where blackening of the 

 pool edges is not objectionable, heavily treating the pool edges with 

 heavy petroleum oil in the winter or early spring serves to prevent 

 breeding for considerable periods of time. 



The malarial group, consisting of Anopheles punctipennis and 

 Anopheles quadrimacidatus, pass the winter in the adult stage and the 

 number of individuals is very greatly reduced by inclement weather. In 

 general this group prefers to breed in clean water but will accept a con- 

 siderable degree of pollution. No member of this group can be considered 

 migratory but there is evidence to show normal movements greater than 

 that which usually occurs with pipiens. 



The distribution of punctipennis is general throughout the state 

 while quadrimaculatus in considerable numbers appears sporadically. 

 Areas having outbreaks of malaria have always shown unusual numbers 

 of quadrimaculatus. On the other hand some areas having a high popu- 

 lation of quadrimaculatus have shown no malaria. It seems that An. 

 quadrimaculatus is a necessary link in the malarial chain while An. 

 punctipennis is not. It also seems that An. quadrimaculatus function in 

 malaria only when human carriers are present. 



In controlling this group breeding water must be removed or im- 

 pounded, rendered free from acquatic plant growth and stocked with 

 wriggler-eating fish. Of course, temporary elimination can be secured 

 by covering breeding waters with larvicide at regular intervals and 

 killing the larvae. 



The miscellaneous group consisting of some twenty species is com- 

 paratively rare and rarely sufficiently abundant to be considered of 

 economic importance. Measures of control adapted to the natural hab- 

 its of the species concerned must be adopted and put into practice. In 

 general removal of breeding waters must be accomplished usually by 

 drainage, or the breeding destroyed by covering the breeding water sur- 

 face with larvicide. 



STEPS IN MOSQUITO CONTROL 



The procedure involved in bringing about the control of these groups 

 involves first of all a knowledge of the composition of the mosquito 

 fauna of the area to which protection is to be given because the size of 

 the area which must be covered depends on the extent to which the mos- 

 quitoes occurring therein have extended flight habits. 



The second step is the charting of all permanent mosquito breeding 



