450 Biology in America 



of the deadly scourge, and one of them (Lazear) laid down 

 his life as a sacrifice to science and to mankind. 4 



The Italian Grassi and the Englishmen Low and Sambon 

 had shown the necessary causative relation between the mos- 

 quito and malaria, and the relation between the distribution 

 of yellow fever and the mosquito genus Stegomyia, led to a 

 strong suspicion of the latter as the villain in the plot. 



The demonstration of the theory was simple enough, but 

 one requiring heroic self-sacrifice on the part of the demon- 

 strators. The story has been so often retold that it may 

 be passed over here in briefest outline. The theory of a 

 causative relation between the mosquito and disease is not 

 a new one. The very ancient literature of India contains 

 suggestions of such a relation, particularly in regard to 

 malaria. Many primitive peoples have had a dim idea that 

 mosquitoes were to blame for the fevers prevalent in low- 

 lying, marshy regions. The Mschamba tribe in Africa avoid 

 such regions for fear of fever. In their language the same 

 word (mbu) is used both for fever and mosquito. "When 

 Humboldt visited the region of the upper Orinoco he found 

 that the natives attributed their fevers to mosquitoes. 



As early as 1848 Dr. Nott of New Orleans suggested the 

 mosquito as the transmitter of malaria and yellow fever, and 

 in 1853 Beauperthuy published an article in the "Gaceta 

 Oficial de Cumana" (Venezuela) in which he advanced a 

 similar theory. Beauperthuy pointed out that yellow fever 

 prevailed when there was a good mosquito crop. He sug- 

 gested that the mosquito injected into the blood of its victims 

 a poison which broke down the red corpuscles, mixing their 

 coloring matter with the blood serum. This poison was 

 obtained by the mosquitoes from decaying matters along the 

 seashore or in swamps. 



In 1881 Dr. Carlos Finlay of Havana, as the result of a 

 careful and extended study of the life history and habits 

 of the Stegomyia mosquitoes and their relation to yellow 

 fever concluded that they were the agents in the spread of 

 the disease, and in 1897 Dr. A. C. Smith of the U. S. Marine 

 Hospital Service, tried an experiment at the national quaran- 

 tine station on Ship Island in the Gulf of Mexico, which was 

 a forerunner of the later work of our government in Cuba, 

 and which strongly supported Finlay 's conclusions. Dr. 

 Smith completely screened the quarantine station where he 

 had under treatment some thirty cases of yellow fever, taken 

 from incoming vessels, and no new cases developed there. 



The final and definite proof of the theory however was made 



4 Subsequently both Reed and Carroll died, probably as the indi- 

 rect result of their work. 



