402 ELEMENTARY BIOLOGY 



439. Fighting flies. Just as soon as we realize the relations 

 of the house fly to mankind, we are likely to be seized with a 

 hatred for the whole tribe of flies ; and perhaps we may be 

 tempted to " swat " every fly that we see. But if we all swatted 

 flies, and did only that, the fly pest would hardly receive a 

 serious check ; for flies breed faster than you and I can kill 

 them, and there is nothing to prevent the flies raised in the 

 stable down the street from coming into our yard. 



We have to attack the insects before they are old enough 

 to fly about ; that is, we must prevent their breeding by either 

 removing or destroying, screening thoroughly, or poisoning, all 

 materials that may serve as food for the maggots. 



The struggle between man and the fly is not a single- 

 handed one, that of a particular person against a particular 

 fly. It is a struggle of one species against another, and 

 we must carry on our end of the fight through community 

 or group action. Better than swatting the fly is the com- 

 plete elimination of the insect from all places inhabited by 

 human beings. 



Many towns have undertaken to exterminate the fly. It has 

 been found that the most effective method is to provide for the 

 systematic removal of garbage and stable manure at least once 

 a week, 1 and to keep streets, back yards, markets, and kitchens 

 perfectly clean. 



On the farm or in a village, stable manure can be profitably 

 spread out upon the ground, in field or garden, every day or 

 two. The manure spread out will dry quickly and be inca- 

 pable of breeding flies. Exposure to sunlight will kill eggs 

 and maggots. In larger towns and cities there should be no 

 difficulty in organizing the work of removing manure and 

 garbage frequently at a comparatively low cost, since the 

 manure is worth gathering for fertilizer and the garbage 

 has a definite commercial value. Where the amount of gar- 

 bage or manure accumulated is so small that its removal is 



. l The life history of the fly covers a period of ten days. 



