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prefer shady pools in which chlorophyll-bearing algae, the chief 
food of Ce. albimana larvae, are relatively absent. 
Ova of Ce. albimana , still creamy-white in colour, were placed in 
a breeding tank exposed to the morning sun on December 3 ; 
temperature of the water, 28'5 to 30° C. (78 to 82 F.). Of these 
ova five became larvae and pupated December 14-15. These pupae 
became imagines during the night of 16-17, making the period from 
ovum to imago about thirteen and a half days. Under these 
conditions they did not get as much sunlight as they would have 
received outside. Sunlight and the abundance of algae undoubtedly 
play a great part in the duration of the period of incubation. It 
should be added that these five mosquitos, two males and three 
females, were placed in a biting jar the morning they emerged 
December 17, and that same evening each one of the three females 
bit and drew blood at once when applied to the arm of a patient. In 
this instance mosquitos bit when not more than twenty-houi hours 
old. 
Into the same tank were placed sixty-eight larvae of An. (?) 
malefactor from ova laid December 3 ; one-third of the ova hatched 
the morning of December 5, the approximate age of the ova, or the 
period of incubation, was thirty-six hours. The tank was supplied 
with algae, spirogyra, and the water aerated. It was noticed very- 
soon that the malefactor larvae did not mature as rapidly as the 
albimana larvae did; when specimens of the latter weie full grown 
the malefactor were only one-third or half grown, and the 
malefactor larvae did not pupate until sixteen to twenty days after 
hatching. 
HARDINESS OF CE. ALBIMANA 
This mosquito is well fitted for the purpose of transmitting 
malarial fever. It is the commonest species here at the present time, 
outnumbering all others, excepting, possibly, A. pseudopunctipenms, 
which latter species is not very hospitable to the malarial parasite. 
It breeds in a great variety of locations ; besides the customary 
pools and margins of streams, collections of rainwater, during the 
dry season it may be found in the stinking water of sewage streams, 
brackish marshes, running streams, meadows, muddy pools, old era 
holes, and in shady malefactor pools and river margins. 
