184 The Philippine Journal of Science 1915 
fully kept separate and bred in a separate jar, and proved to 
be A. maculatus. 
Anopheles sinensis, while not so carefully studied as the pre- 
ceding species, appears to occur in about the same sort of local- 
ities as A. barbirostris, but is much less frequently found. 
We have found larve of A. febrifer and A. barbirostris breed- 
ing in mountain brooks the temperature of which was 23° C. 
and in brooks with a temperature of 28° C. Anopheles rossii 
is often found in small shallow pools exposed directly to the 
tropical sun where the temperature is much higher. 
The different seasons in the Philippines affect the breeding of 
anopheles chiefly through diminution of breeding places in the 
dry season and the flushing of streams during the wet season. 
We have found very young larve of anopheles, apparently of 
A. febrifer, during freshets, in eddies among floating débris. 
Apparently enough eggs or larve remain in a stream after a 
freshet to restock it, even where no females are at hand to 
deposit new eggs. Anopheles rossii may be found in roadside 
puddles or ditches during the rainy season. The stream breed- 
ers, A. febrifer and A. maculatus, require more permanent 
conditions, and their breeding places are consequently more 
restricted. We have found A. febrifer in considerable quantities 
during every month of the year. The year 1914 was somewhat 
exceptional in the Philippines in the lack of long-continued rains 
during the wet season, and this condition favored the stream 
breeders, since they were less disturbed by freshets. In the arti- 
ficial ditches of running water, with which some towns are 
abundantly supplied, the amount of flow varies less from season 
to season than in brooks, so that the breeding of anopheles is 
less interfered with there. 
IMAGOES 
A matter of much importance in the dissemination of malaria 
is the behavior of mature anopheles, especially with reference 
to their habits of visiting houses and biting human beings. The 
avidity for human blood of anopheles in captivity is shown by 
Walker and Barber,’ who give the following percentages for 
females that took advantage of one opportunity to suck blood: 
Per cent. 
Anopheles rossu 63.6 
Anopheles barbirostris 49.4 
Anopheles febrifer 54.8 
Anopheles maculatus 50.0 
Anopheles sinensis 67.8 
* Loc. cit. 
