280 THE HOUSE FLY— DISEASE CARRIER 



been attracted by the presence of these food supphes. 

 Of these 23,087 flies, 22,808 were Miisca domestica, 

 i. e., ninety-eight and eight-tenths per cent, of the whole 

 number captured. The remainder, consisting of one 

 and two-tenths per cent, of the whole, comprised vari- 

 ous species, the most significant ones being Homalomyia 

 canicidaris (the species ordinarily called the ^'little 

 house fly") of which eighty-one specimens were cap- 

 tured; the stable fly (Miiscina stahiilans), thirty-seven 

 specimens; Phora femorata, thirty-three; Liicilia ccesar, 

 eighteen ; DrosopJiila ampclophila, fifteen ; Sarcophaga 

 trivialis, ten; Calliphora erythroccphala, seven. Musca 

 domestica is, therefore, the species of great significance. 

 Homalomyia canicularis is important. Miiscina stabu- 

 lans is of somewhat lesser importance. DrosopJiila 

 ampclophila is an important form, and had more of the 

 captures been made in the autumn its numbers would 

 probably have been greater, since beyond doubt it is 

 an abundant species in houses after fruit has begun to 

 make its appearance (say, in August and September 

 and on until winter time) in pantries and on dining- 

 room sideboards. The Calliphora and the Lucilia are 

 of slight importance, not only on account of their rar- 

 ity in houses, but because they are not true excrement 

 insects. Other forms were taken, but either their 

 household occurrence was probably accidental, or from 

 their habits they have no significance in the disease- 

 transfer function. 



— Extracted from : A Contribution to the Study of the Insect 

 Fauna of Human Excrement. By L. O. Howard (p. 547). 



