170 MOSQUITOES 



ponds ill neigliboriiig woods, and especially with the high 

 brackish sea-coast marshes, that the expense would be- 

 come very great. 



The consideration of the question of remedies may 

 most conveniently be divided into the following main 

 categories : (1) llemedial work against the early stages ; 

 (2) Eemedial work against the adults. 



Eemedial Work Against the Early Stages. 



In considering the question of remedies against the 

 earh^ stages, Ave again find it most convenient to sub- 

 divide the subject as follows : (1) The treatment of 

 breeding-places Avith insecticides ; (2) The abolition of 

 breeding-places by drainage, and (3) The introduction of 

 natural enemies into breeding-pools, which for any rea- 

 son it may be undesirable to drain, or to treat with oil. 



Before undertaking work against the early stages of 

 mosquitoes in any given neighborhood, it becomes neces- 

 sary to make a thorough survey of the immediate sur- 

 roundings, and to learn with great accurac}^ all of the 

 places in which mosquitoes are breeding or may breed. 

 In the section entitled " Queer Places in which Mosqui- 

 toes Breed " (Chapter I.) an effort has been made to cover 

 the ground rather thoroughlv as an indication of what 

 must be looked for. All accidental receptacles for stand- 

 ing water must be emptied and must be kept emptied ; 

 waste ground in the vicinity must be thoroug'hly ex- 

 amined, in order to find whether there are hollows in 

 which rain-water accumulates or whether there are broken 



