THE WAY OF THE FLY 7 



Veeder, writing in 1898, claimed that flies convey 

 typhoid fever in camps. This was followed by Ficker 

 in 1902, and Hamilton in 1903, who discovered that 

 the Bacillus typhosus could be found in flies caught in 

 houses in which typhoid fever cases had been nursed. 



The discovery of the transmission of malaria by a 

 certain species of mosquito known as Anopheline was 

 published by Sir Ronald Ross in a series of scientific 

 articles during the years 1897, 1898, and 1899. He 

 proved that the protozoal parasite of malarial fever is 

 swallowed by these mosquitos when they bite and suck 

 the blood of persons suffering from that disease; the 

 germ of the fever passes through a definite development 

 within the body of the mosquito ; and at length it passes 

 into the salivary glands of the insect and is finally 

 inoculated with the saliva into other persons, and in 

 this way the disease is disseminated. House-flies, how- 

 ever, do not convey disease in this manner, for they do 

 not bite or suck blood; but they do deadly work in 

 a more mechanical or accidental way. The house-flies 

 are a disgusting pest which feed and wallow in filth of 

 all sorts, and when their proboscides and legs are 

 covered with germs which are growing and living in 

 such filth, they proceed to our food and to the food 

 of our children and contaminate it. This infected food 

 we human beings eat and drink, and in this way disease 

 is kept circulating from one person to another in a 

 never-ending cycle, the flies carrying disease from one 

 sick person to the food of others and perhaps to and 

 from animals besides. 



Following the discovery of the transmission of 

 malaria by the agency of the mosquitos the similar 

 conveyance of yellow fever was proved. Then during 

 the Spanish- American War the part played by flies in 



