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yellow fever infection which the other species have not; the infectious 

 germs woulid multiply within the body of the insect and finally reach its 

 salivary and venom glands, to be carried with the secretion of those glands 

 into the track of the wound or into the capillary vessel entered by the 

 sting when the mosquito attacked another victim. 



The Military Yellow Fever Commission, presided over by Dr. Reed, 

 was evidently unacquainted with the last mentioned developments of my 

 mosquito theory when they undertook to investigate it in August and 

 November. 1900, since it was exclusively from precedents recorded about 

 the malaria germ that they were induced to adopt the second procedure 

 which I have outlined above. They have proved conclusively that the surest 

 way of obtaining a distinct experimental attack of yellow fever is by pro- 

 ceeding in the following manner: The mosquito must be applied to the yellow 

 fever patient within the first three days of the attack ; the insect is thereafter 

 to be comfortably quartered in a good-sized jar, provided with sugar and a 

 small cup containing water, in which it may moisten its proboscis and obtain 

 facilities for laying its eggs. With such an arrangement the insect may be 

 kept alive during seventy days or more, though a good many die long before 

 that age. With mosquitoes treated in this manner Dr. Reed and his 

 colleagues have tried to develop an experimental case by applying them to 

 non-immunes five, six, eight and ten days after those insects had bitten 

 the yellow patient, but they have invariably failed to obtain any positive 

 results under these conditions, while they have succeeded in a large 

 majority of their attempts when the application of those same insects had 

 been delayed until) twelve, sixteen or more days after their contamination. 

 From these results Dr. Reed and his colleagues conclude that the yellow 

 fever germ must be a parasite similar to that of malaria, and that, after 

 parting from its human, host, it must go through a series of transformations 

 during the mosquito phase of its existence, requiring at least twelve days 

 for their completion, before it can be in a condition to reproduce the 

 disease. As a corollary to this proposition they believe that my previous 

 experimental attempts must have been failures or errors of interpretation, 

 since they are supposed to have been obtained with mosquitoes contaminated 

 only a few days before the inoculation ; they also claim that their point has 

 been experimentally demonstrated by the fact that their mosquitoes, when 

 applied from five to ten days after their contamination, have invariably 

 given negative results. The investigators thought, no doubt, that by 

 providing their contaminated insects with food and water, besides giving 

 them the benefit of several additional days since their contamination, they 

 were actually improving upon my original technique ; their argument being 

 that since their inoculations had failed, even with those improvements, it 

 was incredible that I should have succeeded in any of my attempts with 

 my simpler method. 



It has, apparently, not occurred to those able investigators while 



