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was high, and sporozoites occurred in the saHvary glands. This 

 species is often found in houses and readily takes blood. It may be 

 found at considerable distances from its breeding places, and although 

 a small mosquito, it is apparently capable of long flight. The evidence 

 goes far to incriminate this species. 



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 experi- 

 mental infection of this species in specimens collected in Malaya. 

 The numbers in the author's experiments were small, but in the 

 experimental series one-third of the specimens dissected was infected. 

 Sporozoites were found in the gut only. 



Anopheles mac}daius. In the author's series this species was largely 

 used as a control of the susceptibility of other species, and he dissected 

 none late enough to obtain sporozoites. One gut-infected specimen 

 was found in nature. 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 harwari. The experiments indicate that this species 

 is highly susceptible to infection under experimental 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 dissected had probably recently emerged. It is 

 difficult to get satisfactory epidemiological evidence, since this species 

 is so commonly associated with A. maculatus. 



Anopheles barbirostris and A. sinensis. Both "are certainly little 

 susceptible to infection experimentally. Only three infected insects 

 were obtained in a large series of A. barbirostris, and only one was 

 obtained in A. sinensis. Stanton has found zygotes in A. 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 JDlood from man, they cannot be wholly acquitted of 

 carrying malaria, but the low percentage of infection and the epidi- 

 miological evidence indicate that neither species is an important 

 carrier in Malaya. 



Anopheles hunteri. The number included in the author's experi- 

 mental series is too small to show anything further than that this 

 species may be infected. 



In regard to the commoner jungle species of Malaya the author 

 has obtained no results from A. 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 negative, 

 but the larvae had been long kept in the laboratory before they 

 emerged, and A. maculatus controls bred under the same conditions 

 were also negative. Anopheles tessellatus was foimd abundantly on 

 one occasion, both in jungle and in pools more or less exposed to the 

 sun, but there was no opportunity of testing them on a carrier at 

 that time. From a small lot of larvae found later, only two adult 

 females were obtained, and both failed to take blood. 



