HABITS OF ADULT MOSQUITOES. 
THE FOOD-HABITS. 
Mosquitoes have engaged the attention of man largely through their bites and 
on this account they have been considered blood-suckers as a group. This, how- 
ever, is far from being the case. There are a great many species, perhaps more 
than half, which never suck blood at all, while others do so but rarely. On the 
other hand there are many species in which the craving for blood is evidently 
very powerful. Everyone will have noticed the impulsiveness of attack in cer- 
tain mosquitoes. Many of these will attack all warm-blooded animals indis- 
criminately. Grassi states that with such species the largest animals attract 
the most; thus a horse will attract mosquitoes more than a man, a man more than 
a dog. Certain species of mosquitoes have a decided predilection for certain 
animals. The yellow-fever mosquito under normal conditions probably feeds 
exclusively upon man: more than this, it will be seen in the chapter on yellow 
fever that this mosquito even discriminates between the different races of man. 
Culex pipiens and Culex quinquefasciatus are closely associated with man yet 
they do not persecute him with the same persistence as Aédes calopus. There is 
reason to suppose that these species of Culex are primarily persecutors of poultry. 
It will be remembered that Ross, in India, in his original investigations with 
a malarial disease of sparrows, found that this was transmitted by Culex quin- 
quefasciatus. There are malarial diseases of other birds, probably carried by 
other mosquitoes. MacCallum’s original observation in which he discovered the 
true meaning of the flagellate bodies, the real males of Proteosoma, was made 
in studying a malarial disease of the American crow. 
Captain James, who investigated the blood diseases of birds, states that “ the 
voracity with which Culex mosquitoes (C. fatigans) [=C. quinquefasciatus] 
will gorge themselves upon the blood of sparrows is extraordinary, and if too 
many mosquitoes are put in the cage with the same sparrow they will literally 
bleed it to death.” 
Goeldi, in discussing the habits of Culex quinquefasciatus in comparison with 
Aédes calopus, touches upon this adaptation as follows: 
“ T have the impression that, in general, Culex fatigans behaves more contrary, 
obstinate, timid, refractory to domestication and comprehension: I believe 
that I can perceive significant proof of this in the singular circumstance that in 
all the trials made with this species of mosquito I only succeeded in inducing a 
single individual to bite, either among those captured or those bred in captivity. 
I attribute to it a degree of intelligence decidedly inferior to that of Stegomyta 
fasciata. This accords well with my idea that, in the same manner as the other 
blood-sucking insects, this species of Culicid has a primary relation to a definite 
and determinate species of vertebrate host. I feel induced to say that in Culex 
fatigans we have a mosquito primitively less addicted to the human species than 
to certain domestic animals, amongst which, my suspicion points principally 
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