I'lr.HTING THE PANAMA jMOSOUITU WITH. 011^ 



These sanitar\- drip-barrels automatically spread oil, drop by drop, over pools, streams, 

 and marshy places, thereby preventing the mosquito from breeding in the water. "He (Ross) 

 proved beyond any peradventure that the Anopheles mosquito is the intermediate host, and 

 that no one can contract malaria except he be bitten by a mosquito which has previously 

 1)itten a person sufferin.g from that disease" (see page 347"). 



l)laine upon the mosquito, and charged 

 that it introduced a poison similar to 

 snake venom into the human system 

 throuqh the biting process. 



Step by step a closer approach to tlie 

 truth was made, and in 1883 Sir Patrick 

 Alanson demonstrated that the mosquiti) 

 was the intermediate host of the l)lood 

 parasite filaria. 



l-')iit it was not until Sir Ronald Ross 

 arrived upon the scene with his investi- 

 gations that the real truth of the prin- 

 ci])le of insect-borne diseases came to be 

 tinilerstood. Prior to this Laveran had 

 succeeded in isolating the germ of ma- 

 laria ; and, building upon this foundation, 

 Ross labored to ascertain the exact rela- 

 tion between man and the niosqitito. 



34*^ 



