THE ECONOMIC IMPORTANCE OF ANIMALS 225 



season, will all play a part in the reduction of flies. To the motto 

 " swat the fly " should be added, "remove their breeding places!" 



Other Insect Disease Carriers. Fleas and bedbugs have been 

 recently added to those insects proven to carry disease to man. 

 Bubonic plague, which is primarily a disease of rats, is un 

 doubtedly transmitted from the infected rats to man by the fleas. 

 Fleas are also believed to transmit leprosy although this is not 

 proven. 



To rid a house of fleas we must first find their breeding places. 

 Old carpets, the sleeping places of cats or dogs or any dirty un- 

 swept corner may hold the eggs of the flea. The young breed in 

 cracks and crevices,, feeding upon organic 

 matter there. Eventually they come to live 

 as adults on their warm-blooded hosts, cats, 

 dogs, or man. Evidently destruction of the 

 breeding places, careful washing of all in 

 fected areas, the use of benzine or gasoline Flea which transmits Bu- 

 in crevices where the larva? may be hid are ^ onic plague from rat 



17 to man. 



the most effective methods of extermina 

 tion. Pets which might harbor fleas should be washed frequently 

 with a weak (two to three per cent) solution of creolin. 



Bedbugs are difficult to prove as an agent in the transmission of 

 disease but their disgusting habits are sufficient reason for their 

 extermination. It has been proven by experiment that they may 

 spread typhoid and relapsing fevers. They prefer human blood 

 to other food and have come to live in bedrooms and beds because 

 this food can be obtained there. They are extremely difficult to 

 exterminate because their flat body allows them to hide in cracks 

 out of sight. Wooden beds are thus better protection for them 

 than iron or brass beds. Boiling water poured over the cracks 

 when they breed or a mixture of strong corrosive sublimate four 

 parts, alcohol four parts and spirits of turpentine one part, are 

 effective remedies. 



How the Harm done by Insects is Controlled. The com 

 bating of insects is directed by several bodies of men, all of 

 which have the same end in view. These are the Bureau of 

 Entomology of the United States Department of Agriculture, 



HUNTER, CIV. BI. 15 



