THE TIME FOR FLY-REDUCTION 



31 



hand, the total numbers of the flying insects which can 

 be caught and killed is very small compared with the 

 numbers of larva? which can be dealt with. It is of 

 little use trying to kill flying wasps, mosquitos, or flies ; 

 the amount of killing we can do will not seriously affect 

 the total numbers of these insects. They should be 

 attacked when they are crawling, wingless creatures, 

 and they should be dealt with in their lairs, where 

 the grubs can be found in enormous numbers. In this 

 way only can flies be reduced satisfactorily. It requires 

 organisation and perseverance, but it is well worth these, 

 for lives will thus be saved. 



Fly-eggs, larvae, and pupa. 

 (After Martin.) 



The pupa taken from inside the pupa-case. 

 (After Howard.) 



