454 



FOODS 



mosquitoes from biting is to exterminate them. Since 

 mosquitoes breed in stagnant water, all old ditches or 

 small pools where water accumulates should be emptied and 

 drained. Larger stagnant pools should be drained or have 

 a film of kerosene spread over their surface by frequently 

 pouring a little of the oil on the water. This will keep the 

 mosquitoes from breeding and prevent the diseases. 



The Texas fever, which has caused such great financial 

 losses to the cattlemen of the United States, is caused by a 

 protozoan injected into the cattle by the bite of a tick. 



Bubonic plague, the " Black Death " that swept Europe 

 during the Middle Ages, is spread by the bite of a flea that 

 lives on plague-infested rats. Hundreds of thousands of 

 dollars have been spent by the Government in killing rats 

 in some of the ports of the United States where the plague 

 has succeeded in landing. Many seaports are now rat- 

 proofing their wharves in an effort to exterminate these pests. 



The cables holding ships to the 

 docks are often passed through 

 holes in the centers of metal 

 sheets in order to prevent rats 

 from entering a ship by walking 

 along the cables. Sailors have 

 learned that if the rats are kept 

 out, the plague is kept out. 



HOUSE FLY (Magnified) 



Flies. The words fly and 

 filth are almost synonymous. 

 Flies breed in any kind of de- 

 caying vegetable or animal matter. The eggs hatch in 

 about a day and the little white maggots after absorbing 

 filth for about ten days change into adult flies with their 



