THE MALARIAL MOSQUITO 121 



human bodv from the infected mosquitoes. They pass down the 

 hypopharynx or salivary tube, while blood and malarial "gametes pass 

 up the labial tube to the mouth. 



They feed mostly at night, but may do so at any time of the day. 



Thev become blown out with blood, then retire to digest it. 



Next morning the female Hies to the nearest water to lay her eggs; 

 she ma_y travel half a mile for this if it is necessary. 



The Anopheles prefer clean water with weeds, the Culicina^ any 

 kind. 



The Anopheles eggs may be found in the back-eddies of streams, 

 margins of lakes, large wells, puddles, in broken bottles, shells, holes 

 of rocks and trees, and in plants like bamboos, pineapples, &c. 



At night the female seeks blood again. 



The larvffi are cannibals, living on each other as well as on algse. 



These larv^ must be attacked by the medical officer everywhere, 

 or he can only protect himself with nets and drugs. 



In the dry season mosquito-larvaj can ^estivate and wait for more 

 suitable conditions. 



The adult lives for about four weeks, not counting hibernating 

 periods. 



One adult mosquito can give off 200,000,000 in four months 

 (Ficalbi). 



Adults may be transported great distances in ships, railway 

 carriages, but it is by accident and not by choice. 



The mosquito engorges herself with blood in one minute. 



She begins to secrete the liquor sanguinis almost at once, this being 

 the refuse of digestion. 



The peculiar buzzing noise so well known to tropical residents is 

 due to the vibration of its proboscis, and has no relation to the wing 

 movements (Darling). 



Darling affirms that Anopheline females will suck blood at any 

 time and do not wait for fecundation. 



Ross says that the female sucks blood after fecundation, also that 

 the male only lives for a few days. 



Darling says that the male lives fifteen to nineteen days, e.g., as 

 long as the female when suitable food is available, such as sliced 

 banana, &c. 



Mosquitoes are not confined in their attacks for blood upon man, 

 for they are known to attack invertebrates, e.g., insects, and also 

 young fish. 



Possibly a quarter of the total number of anopheles may succeed 

 in biting human beings once. A third of these may live for a further 

 ten days, of which only a quarter may succeed in biting again. 



