178 The Philippine Journal of Science 1915 
tained viable gametes at the time of experiment from the fact that 
at least one mosquito at each feeding became infected. Taking 
into consideration all of the experiments, the numbers and per- 
centages are as follows: 

| Species. - Der | Infected. 



| 
Per ct. 
Anopheles febrifers>. +. ee ee eee ee ee eee eee 373 35+ 
Anophelesimaculatits= see ae ser ere en oe ee a a aE, 49 6+ 
Anopheles rossit pia eae ee ee eee ee es ee es Se 642 10— 
Anopheles bar birostris 5 pace ee ie ee oe 205 | 3+ 
Anopheles svip|73t3 aS Se Re ela ee Sat eee a 18 0 
With regard to sporozoites in the salivary glands the numbers 
are as follows: 








Salivary glands. 
Species. | Infected. 
Dis- 
sected. | 
Number. | Per cent. 
Anopheles tfebriufer tc. 2-2ee 2 nese Ae eee eee ee ll 20 18+ 
Anopheles maculatus=-) 226-5 > Se Cee 2a eee 1 1 100 
MAN ODNELES TOSSUD an sas ee ne ne ee el ee 125 0 0 
| Anopheles i0G7, DU OStT:7S ae ae a ee ee 75 0 | 0 
Taking into consideration these percentages and the numbers 
and distribution of anophelines as far as then known, it was 
concluded that Anopheles febrifer was probably the chief carrier, 
or one of the chief carriers, in the Philippine Islands. 
The object of the present work has been to study more widely 
the distribution of the commoner anophelines of the Archi- 
pelago and the distribution of endemic malaria as determined 
by the parasite and spleen indexes of children, for the most part 
of children ten years and less of age. Special attention was 
given to the relation between the breeding places of anophelines 
and the presence of malaria. The contiguity of the breeding 
places of anophelines to inhabited places, the character of sur- 
roundings, and other factors were also studied with the aim of 
determining why one locality is malarious and another not. 
Data were obtained on the habits of anopheline larve and 
imagoes, and some experiments in the destruction of the larve 
of Anopheles in running streams were carried out. In short, 
our aim has been to establish a scientific basis for combating 
malaria in the Philippine Islands. 

