ii2 Mosquitoes 



those of Finlay, that 5. calopus is tne only agent 

 transmitting the disease. 



Strangely, and, what is more, dangerously, the 

 French Commission reports that there is no danger 

 of an infected mosquito biting in the day, and that 

 Stegomyia attacks thus only in the first week and a 

 half of its life, after that feeding only at night. This 

 last is certainly not the case in Baton Rouge and 

 New Orleans, as the insect may bite there at any 

 time of day, if it be not too sunny, and there is no 

 reason to think that a free, infected mosquito would 

 do any differently from those fed on ordinary blood; 

 these last certainly make subsequent meals during 

 the daylight hours. Therefore, notwithstanding the 

 French to the contrary, gloves and veils are not to 

 be despised as a means of protection during an epi- 

 demic, in this country at least. Nevertheless the 

 prophylactic measures adopted by the French at Rio 

 have lowered the mortality, from 2500 to 2000 

 annually, to 45. 



But if the French Commission firmly believes that 

 J>. calopus is the only agent of transmission, it also 

 holds that, during the first three days of the disease, 

 the mosquito can be infected otherwise than by 

 biting a patient with characteristic yellow fever. 



It, as well as others, has admitted the fact that 

 there is always a latent source of danger in the weak- 

 ened yellow fevers unrecognised by the physicians, 

 which, nevertheless, furnish the elements of infection 

 to the mosquitoes. Among these weakened yellow 

 fevers MM. Marchoux and Simond quote particularly 

 those of very young children, who oppose to the 



