﻿528 BANKS. 



Blood-sucking. — The females of these mosquitoes attack readily in 

 the evening; during the day it is not easy to persuade them, even when 

 the receptacle containing them is covered with a black cloth. When 

 one of the insects settles upon a chosen spot, its palpi are immediately 

 elevated and the stylets of the proboscis inserted, sometimes to within 

 less than a millimeter of their base. During the process of inserting 

 the stylets, the female wriggles her palpi in a manner which seems plainly 

 to suggest the pleasure which the act affords. After she has begun to 

 draw blood, the motion of the palpi decreases somewhat, but does not 

 entirely cease until she has completed the meal and withdrawn her 

 proboscis. 



An invariable habit of these mosquitoes while feeding on blood for 

 the first time is that of voiding a serum-like liquid from the anus in a 

 continuous stream of droplets. This is succeeded by pure blood with the 

 corpuscles intact. An amount equal to that retained in the body will 

 frequently be expelled in this manner in five or six minutes from the 

 time the insect begins to bite. These dejecta retain all the microscopic 

 appearances of uningested blood, excepting that the corpuscles are fewer 

 in number, the greater part having been retained, probably in the stomach. 

 All dejecta, subsequent to this peculiar one, are of the normal flyspeck 

 kind, and contain the usual waste products of digestion. It appears as 

 if the first meal of blood which the insect takes, acts as a very rapid cathar- 

 tic and prepares the system for the digesting and assimilating of succeed- 

 ing meals. 5 Unfortunately, no observations were made upon mosquitoes 

 fed, previous to sucking blood, on the juice of bananas. 



Susceptibilities and idiosyncrasies. — Female mosquitoes of this spe- 

 cies stand confinement very much better than males, the latter dying 

 in from two to four days after emerging, even when abundantly supplied 

 with food which they appear to enjoy. The females may be kept alive 

 for at least twenty-three days by feeding them on blood every alternate 

 day. It has been stated that unmodified sunlight is fatal to the adult 

 mosquito, but the males succumb to such conditions very much more 

 rapidly than the females. The) r are in every way more fragile than the 

 other sex. They have never been seen to gorge themselves, either with 

 juice from ripe bananas, water or sugar sirup, as do the females, and 

 of course they positively do not suck blood. This has been thoroughly 

 demonstrated by trials with more than five hundred male mosquitoes 

 under every condition which could arise. If they can be directed to a 

 drop of blood placed on the side of the vessel containing them, they will 

 sip it up daintily for a short time, but never remain at it, as do the 

 females, until the last bit has been drawn up. 



5 It may be that the saline character of the blood gives it this cathartic effect. 



