CHAPTER X 



INSECT TYPE PROBLEMS: IMPORTANT FLIES 



If each egg of the common house fly should develop, and each of the 

 larvae should find the food and temperature it needed, with no loss and n'o 

 destruction, the people of the city in which it happened would suffocate 

 under the plague of flies. JORDAN and KELLOGG, " Evolution and Animal 

 Life," p. 59 



And as for the typhoid fly, that a creature born in indescribable filth 

 and absolutely swarming with disease germs should be practically invited 

 to multiply unchecked, even in great centers of population, is surely nothing 

 less than criminal. L. O. HOWARD 



What flies do. During the Spanish-American war typhoid 

 fever wounded 20,738 United States soldiers and killed 1580. 

 The chief means of spreading this infection were the swarms 

 of flies .which infested the army encampments. To emphasize 

 this menace to health, Dr. Howard has suggested that we 

 change the name of the house fly to typhoid fly. This opened 

 the way for thorough investigation of the insect, and its filthy 

 habits were soon found to render it the possible distributor 

 for many other filth-disease infections. Tuberculosis, cholera, 

 enteritis (including epidemic dysentery and cholera infantum 

 the fly-time "summer complaint" of infants), spinal menin- 

 gitis, bubonic plague, smallpox, leprosy, syphilis, gonorrhea, 

 ophthalmia, and the eggs of tapeworms, hookworm, and a num- 

 ber of other parasitic worms for all these and many more the 

 fly has been discovered to be a ready actual or potential carrier. 

 Since the fly is proved to be such an active agent of transmis- 

 sion between all manner of filth, on which it feeds and in which 

 it breeds, and human foods, Dr. Stiles, of the Hookworm 

 Commission, has proposed to call it the filth-disease fly. 



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