The extent to which anopheline mosquitoes infected with the parasites of human malaria can be depended upon to infect the patients to whom they are applied is a matter of considerable importance in their use in malaria therapy, as well as a matter of distinct epidemiological significance. Observations made in our service up to the end of 1935 have been analyzed from the standpoint of possible interrelationship between the following factors:
(a)The number of infected mosquitoes employed in the inoculation.
(b)The qualitative character of the infection, i.e., the per cent infected in the lots to which infected mosquitoes belonged, and
(c)The quantitative character of the infection, i.e., the cyst density on the stomachs of the infected mosquitoes of the several lots.
(d)Inoculations and takes from the use of vivax infected mosquitoes on white patients, and inoculations and takes from the use of falciparum infected mosquitoes on negroes.