528 JOURNAL OF ECONOMIC ENTOMOLOGY (Vol. 9 



ous to be troublesome. The fungus invariably holds the insect in 

 cheek. A majority of the young caterpillars die within ten days after 

 hatching. 



Although "cholera" often arrives too late to save the crop if the 

 farmer depends upon it alone, it is nevertheless a great help as it 

 reduces to a few weeks the time during which the farmer needs to 

 apply arsenicals. 



SOME NOTES CONCERNING OVERWINTERING OF THE 

 HOUSE-FLY, MUSCA DOMESTICA, AT DALLAS, TEXAS^ 



By W. E. Dove, United Stales Department of Agriculture, Bureau of Entomology 



From the facts that adult house-flies are found in dormant, semi- 

 dormant and active states in mid-winter, and possess a greater longev- 

 ity during low temperatures, earlier investigators have generally 

 assumed that the species passed the winter in the adult stage. This 

 conclusion is further supported by the fact that numbers of inviable 

 pupffi have been taken in nature during the early spring. The treat- 

 ment of manure piles with borax and hellebore and the effectiveness 

 of the maggot trap in control of house-flies has necessarily caused us to 

 recognize the overwintering of Musca domestica as a biological point 

 worthy of more consideration and one which should be supported by 

 more experimental evidence. 



Under the direction of Dr. W. D. Hunter, and at the suggestion of 

 Dr. L. 0. Howard, some biological points of economic importance were 

 made a subject of study at Dallas and Uvalde, Texas. We have 

 recorded two instances in which we succeeded in carrying the imma- 

 ture stages of the species over the winter in infested manure (1) . Due 

 to the fact that Empusa muscce was unusually abundant and probably 

 killed most of our adults, we did not attempt to ascertain the winter 

 longevity. Further experiments with immature stages and with the 

 longevity of adults are herein reported. I am gratefully indebted to 

 Mr. F. C. Bishopp under whose direct supervision the work was done 

 for valuable suggestions. 



Adult Longevity 

 I wish to quote Mr. R. H. Hutchison (2), who reports that "in one 

 hibernation experiment, in which flies were kept in a stable varying 

 from 30° to 60° F., a few lived as long as 70 days." This experiment 

 was conducted at a more northerly latitude than Dallas, Texas, and 

 where temperatures are more constant. 



^ Published by permission of Chief of Bureau of Entomology. 



