MOSQUITOES and J ELLOW PI v i 1;. 19 
Physicians have been theorizing about the cause of yellow fcwr 
from ili«' time when they began to treat it. It was thought by many 
iliai it was carried in the air: by others that it was conveyed l»\ tin 1 
clothing, bedding, or Other article- which had come in contact with a 
yellow-fever patient. There were one or two early suggestions of the 
agency of mosquitoes, hut practically no attention was paid to them, 
and they have been resurrected and considered significant only since 
the beginning of the present century. With the discovery of the 
agency of micro-organisms in the causation of disease, a search soon 
began for some causative germ. Many micro-organisms were found 
in the course of the autopsies, and many claims were put forth by 
investigators. All of these, however, were virtually set at pest by 
Sternberg in his " Report on the Etiology and Prevention of Yellow 
Fever," published in L890, hut a claim made by Sanarelli in June, 
iv.>7. for a bacillus which hi' called Bacillus icteroides received con- 
siderable credence, and in lst> ( .> it was accepted in full by Wasden and 
Geddings, of the United States Marine-Hospital Service, who re- 
ported that they had found this bacillus in thirteen or fourteen cases 
of yellow fever in the city of Havana. There is no evidence, how- 
ever, that this bacillus has anything to do with yellow fever. In L881 
Finlay, of Havana, proposed the theory that yellow fever, whatever 
its cause may be. is conveyed by means of Culex (now Stegomyia) 
fasciatus (now calopus). Subsequently he published several im- 
portant papers, in which his views were modified from time to time, 
and in the 1 course of which he mentioned experiments with loo indi- 
viduals, producing 3 cases of mild fever. None of the cases, however, 
was under his full control, and the possibility of other method- of 
contracting the disease was not excluded. Therefore, his theory, 
while it was received with interest, was not considered to he proved. 
In 11)00 came the beginning of the true demonstration. An army 
board was appointed by Surgeon-General Sternberg for the purpose 
of investigating the acute infectious diseases prevailing in the island 
of Cuba. The result achieved by this hoard, consisting of Reed, 
Carroll, Lazear, and Agramonte, was a demonstration that yellow 
fever is carried ^y Stegomyia calopus, and their ultimate demonstra- 
tion was so perfect a- to silence practically all expert opposition. The 
Third International Sanitary Convention of the American Republics 
unanimously accepted the conclusion that yellow fever is carried by 
this mosquito, and that the Stegomyia constitutes the only known 
mean- by which the disease is spread. To-day, after abundant addi- 
tional demonstration, the original contention of Reed, Carroll, and 
Aiiranionte ( Lazear having died in the course of the experiments) is 
a part of the accepted knowledge of the medical world. I'he im- 
portance of the discovery can not he overestimated, and it- first 
demonstration was followed by antimosquito measures in the city 
