CHAPTER VIII 



Important Phases in the Life History of the Non-Biting Flies ^ 

 W. Dwight Pierce 



In the preceding lecture there was brought together an accumulation 

 of evidence against the common flies that frequent our houses which 

 should convince any one of the absolute necessity of keeping flies from 

 our food, our houses and our bodies. We can only hope to accomplish 

 this object by becoming familiar at least with the more important features 

 in the life history of the flies. From the study of the transmission of 

 diseases we may pick out for example a few points in the biology which 

 need to be stressed, such as feeding habits, regurgitation of food, excreta, 

 breeding places, oviposition, flight, attraction to odon 



We are dealing in this lecture not only with the common house fly 

 but also with most of the common flies which frequent our houses and are 

 known as domestic flies. Of the common household flies, only one, the bit- 

 ing stable fly, StOTnoxys calcitrans, is omitted for future discussion. 



Students would do well to examine some book in which the diff'erent 

 species are illustrated, so as to become familiar with the characteristic 

 markings. It will then be a good plan to collect the various flies around, 

 the house and determine their species. 



Fairly good illustrations of common household flies are given by 

 Howard and Hutchinson (1915), and Richardson (1917). 



The best illustrations of the flies are contained in Patton and Cragg's 

 textbook (1913). 



Tables to species of common flies and also illustrations are presented 

 by Riley and Johannsen (1915). 



It is also desirable to know how to identify the fly larvae when found. 

 The best American work on this subject is by Banks (1912). See also 

 Riley and Johannsen, p. 315. 



For general information on the life history, morphology, and anatomy 

 of the house fly refer to Hewitt (1917). 



The flies are classified largely on the characters of the proboscis, 

 antennas, wing veins, eyes and the arrangement of hairs. The larvas are 

 classified on the characters of the spiracles, the cephalo-pharyngeal 

 skeleton, tubercles, hairs and processes. 



'This lecture was read July 22 and distributed July 29, 1918. 



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