Mosquitoes and Malarial Fever 541 



of mosquitoes can be greatly diminished. Fortunately 

 this is particularly true with reference to the mosquitoes 

 most concerned the anopheles which fly but short dis- 

 tances. By closing all the domestic cisterns and reservoirs, 

 cesspools, etc., so that no mosquitoes can get in to breed 

 or get out to bite, and by draining the pools for half a mile 

 in all directions from human habitations, the number of 



Fig. 182. Anopheles maculipennis : Adult male at left, female at right 



(Howard) . 



anopheles mosquitoes can be made almost negligible. If at 

 the same time no mosquitoes are any longer permitted to 

 infect themselves by biting infected human beings, the 

 spread of the disease must be greatly restricted or checked. 



MOSQUITOES AND MALARIAL FEVER. 



In order that the student may be able to differentiate 

 with reasonable accuracy such mosquitoes as come under 

 his observation, use must be made of tabulations, to cor- 

 rectly use which, however, the student should have some 

 familiarity with insect structure and the general principles 



