SB 

 818 

 C578 

 ENT 



Mo. 35, Second Series. 



nited States Department of Agriculture, 



DIVISION OF ENTOMOLOGY. 



HOUSE FIJES. 



(Musca doiiicsticd ct a1.) 



There are several species of flies which are commonly found in 

 houses, although but one of these should be called the house fly 

 proper. This is the Musca domesticd, and is a medium-sized grayish 

 fly with its mouth parts spread out at the tip for sucking up liquid 



Fig. 1. — The eommon house fly \Mu»ca ili>mrstica) : a. adult inak'; I), jn-dhosci.s 

 and palpus of .same; c. terminal joints of antenna; d, head of female; r, pupa- 

 rium; /, anterior spiracle — all enlarged (author's', illustration). 



substances. It breeds in manure and dooryard filth and is found in 

 nearly all parts of the world. On account of the conformation of its 

 mouth parts, the house fly can not bite, yet no impression is stronger 

 in the minds of most people than that this insect does occasionally 

 bite. Thi\ impression is due to the frefpient occurrence in houses of 

 another fly {Stomoxys cnlcitran.s) ^ which may be called the stable fly. 

 and which, while closely resembling the house fly (so closely, in fact, 

 as to deceive anyone but an entomologist), ditfers from it in the 

 important particular that its mouth parts are formed for piercing the 

 skin. It is perhaps second in point of abundance to the house fly in 

 most portions of the northeastern States. 

 15164— No. 35—06 m 



