Vol. XXVi] ENTOMOLOGICAL NEWS. 263 



How Does the House-fly Pass the Winter? (Dipt.). 

 By Hf.nry Skinner. 

 In Ftitomological News, xxiv, 303, 1913, I iHibIishc<I an 

 article with the above title and stated that I believed that in 

 the vicinity of I*hiladelphia Muscn domrstica lived through the 

 winter in the pupal stage. This article led Dr. S. Moncton 

 Copeman and Mr. E. E. Austen to investigate the same sub- 

 ject in England. They published the results of their investi- 

 gations in "Reports to the Local Government Board on Pub- 

 lic Mealth and Medical Subjects, New Series, No. 102, 191 4, 

 London, England." They sent out appeals, for specimens, to 

 be published in certain journals. The notice was printed in 

 •*(' Life," "The Entomologist" and "The Entomologists' 



M Magazine." From January 19 to April 27 they received 



fifty-eight consignments of flies, representing fifteen species. 

 They gave an extensive tabakted report of the specimens re- 

 ceived which is ver)' interesting and instructive. Their sum- 

 mary and conclusion is as follows : "It will be seen from the 

 appendix that the results obuined afford no support to the be- 

 lief that house-flies hibernate in this country [Engbnd] in the 

 adult state. The few specimens of Musca domtstica sent in 

 were all taken in an active condition ; some of the other flies, 

 however, such as the extremely common Potlmia rudis F., 

 were often found partially dormant, and it is diflicult to resist 

 the conclusion that did the house-fly really hibernate in the 

 adult sUte some evidence of the fact must have been ob- 

 tained. The idea suggests itself that the relative lateness of 

 the season at which house-flies annually become abundant may 

 be due to the smallness of the number of individuals that, in 

 an active condition, survive the winter in houses and other 

 buildings, although it must be admitted that as yet [there is] 

 nothing in the shape of proof that female house-flics found 

 alive at the end of winter actually survive until ovijwsition 

 takes place." They say in conclusion "it would ai>pear thai 

 the customary explanation of the perpetuation of the house- 

 fly from year to year has now been fairly tested, and that the 

 evidence obtained fails to supiHjrt it." 



