INSECTS OF THE HOUSEHOLD 



63 



we see why it is that from a very few individuals in early 

 spring we may have swarms of flies by midsummer. 



The stable fly, Stomoxys calcitrans, is commonly mis- 

 taken for the house fly, which it closely resembles, but 

 differs from it in having its mouth parts formed for 

 piercing the skin. Its bite is painful, and while it is not 

 poisonous, it may carry disease from animal to animal or 

 even to man. We often see horses, cattle, and dogs sur- 

 rounded by swarms of these 

 flies, and, aside from the 

 actual suffering and annoy- 

 ance they cause, they must 

 occasion the loss of pounds 



Fig. 20. House Flv 

 a, ^gg ; b, larva or maggot ; <;, pupa case, or puparium ; d, adult male. (All enlarged) 



of flesh and gallons of blood and milk during a season. 

 These flies probably lay their eggs on manure, and with 

 this covering our fields and pastures, we shall not be able 

 to prevent them from breeding in the country. In cities 

 stable pits may often be made fly proof with but little 

 additional expense. 



The bluebottle fly, Calliphora crythrocephala, is a third 

 species that children can readily learn. It breeds in 

 decaying animal matter. If a fish head or a piece of 



