34 The Philippine Journal of Science 1918 



Anopheles kochi. — No special study was made of this species, 

 and only such specimens as happened to be collected with other 

 species were exposed to gamete carriers. A high percentage of 

 gut infections was obtained, but none were dissected late enough 

 to observe any formation of sporozoites. 



Anopheles fuliginosus. — Stanton reports both natural and ex- 

 perimental infection of this species in specimens collected in 

 Malaya. The numbers in my experiments were small, but in 

 the experimental series one third of the specimens dissected 

 was infected. Sporozoites were found in the gut only. 



Anopheles maculatus. — In my series this species was largely 

 used as" a control of the susceptibility of other species, and 

 I dissected none late enough to obtain sporozoites. The one 

 gut-infected specimen found in nature has been mentioned in 

 connection with Table XV. However, the works of Watson, 

 Stanton, Strickland, and others have established the fact that 

 this species is one of the most important carriers in Malaya. 



Anopheles kawari. — The experiments in this series indicate 

 that this species is highly susceptible to infection under experi- 

 mental conditions. The percentage of gut infections was high, 

 and sporozoites were formed in the salivary glands. None were 

 found infected in nature, but nearly all of the specimens dis- 

 sected had probably recently emerged. It is difficult to get 

 satisfactory epidemiological evidence, since this species is so 

 commonly associated with maculatus. 



Anopheles barbirostrls and sinensis. — Both are certainly little 

 susceptible to infection experimentally. Only three infected 

 insects were obtained in a large series of barbirostris, and only 

 one was obtained in sinensis. Stanton has found zygotes in 

 sinensis in nature. In view of the facts that these species may 

 be infected with malaria, that they occur in large numbers, and 

 that they readily visit houses and take blood from man, they 

 cannot be wholly acquitted of carrying malaria, but the low 

 percentage of infection and the epidemiological evidence indicate 

 that neither species is an important carrier in Malaya. 



Anopheles hunteri. — The number included in my experimental 

 series is too small to show anything further than that this 

 species may be infected. 



In regard to the commoner jungle species of Malaya I have 

 obtained no results on aitkeni further than to prove that it will 

 take blood when exposed to a carrier. Of those taking blood, 

 the single one that lived long enough to be dissected was neg- 

 ative, but the larvae had been long kept in the laboratory before 

 they emerged, and maculatus controls bred under the same con- 



