86 NATURE-STUDY REVIEW [12:2— Feb., 1916 



will be convinced and see the need and really wish to do his part. 

 Development of " co-operative good will," in a community, with 

 the basis of general knowledge necessary to it, is the vital end in 

 view, and this most precious community asset cannot be formed 

 around foolish proposals or objectionable selfish schemes. 



Education about the natural history of flies — their feeding and 

 breeding habits and what they do — is, of course, in order; and 

 especially ideas of real cleanliness in disposal of garbage and stable 

 wastes and any other organic matter. While no amount of this 

 matter will breed any flies, unless the breeders are there to lay the 

 eggs in it, decency on other accounts, requires that it be put into 

 or on the ground daily in warm weather. If spread thinly, it will 

 dry out, and slowly disintegrate as rains beat it into the ground, 

 or if raked into the surface the bacteria of the soil will take care 

 of almost unbelievable quantities of organic wastes without the 

 least nusiance and so quickly that flies cannot develop. Fresh 

 lawn clippings, or weeds, for example, if left in a heap may quickly 

 become a nuisance by rotting, whereas, if spread thinly about the 

 roots of trees or between rows of berry bushes or corn become 

 valuable mulch. 



One important fact, proved by recent experiments of the Depart- 

 ment of Agriculture, is that flies are unable to find foods among 

 the animal wastes of stables with which they can produce eggs. 

 Mosquitoes may subsist for some time on vegetable juices, of 

 fruits, etc., but cannot make eggs until they have filled with blood. 

 So flies require rich foods like milk, eggs, meat, etc., in order to 

 develop their eggs. This greatly simplifies the problem. By 

 care against leaving fly foods uncovered and against scattering 

 or slopping them about, we can starve the flies into our traps 

 and so effectually prevent breeding. 



Finally, clear headed, logical, really easy, effective and economi- 

 cal fly prevention consists in getting all the breeders, letting them 

 trap themselves, before they have time to lay their eggs. This 

 done, we can dispense with screen windows and doors, tanglefoot 

 paper and dangerous fly poisons, laborious treatment of stable 

 wastes and maggot traps, and be free from the world's oldest, 

 most troublesome and dangerous pest. 



What flies do. During the war with Spain the United States 

 had 20,788 soldiers wounded and 1,580 killed by typhoid fever. 

 It was found that flies spread this infection and Dr. Howard, 



