THE HOUSE FLY 



even millions of disease microbes from infected matter to 

 our food substances. 



On the approach of winter most flies die of cold. Others 

 hibernate in houses and other warm situations. On the 

 approach of the warmer season they again start their chief 

 business in life, which is that of laying eggs, and incidentally 

 transferring the microbes of diseases to our food material. 

 If every hibernating fly was killed during the winter months 



FIG. 3. 



EGG OF A HOUSE FLY, showing the larva or grub 

 issuing forth. The maggot devours decaying 

 animal and vegetable filth, and in a week's time 

 turns into a chrysalis. (Enlarged.) 



(From the National Geographic Society, Washington, D.C, 

 Copy right, 1913, by special permission.) 



in dwellings by suitable fumigation, the plague of flies the 

 following spring could be considerably checked. 



A single female fly is capable of laying four batches of 

 eggs before she dies, although numbers of them die shortly 

 after laying one batch. 



Now, supposing a female fly has survived the winter in 

 some crack, behind a picture, or loose wallpaper in a dwell- 

 ing house, and issues forth in the spring. She instantly 



