FLIES THAT FREQUENT HOUSES 41 



In this event, it would be impracticable to control it in 

 the same way as we would the house-fly. 



The clusters of flies found in the corners of rooms may 

 be swept into boiling water and killed. Fresh pyrethrum 

 or buhach dusted freely on them will kill or stupefy them 

 so that they may be swept up and burned. 



Screens afford little protection against cluster-flies. A 

 correspondent writes that, "The only way I have found 

 to keep them out of the room is to leave out screens, 

 lower the window from the top, and have the room light." 

 Fortunately, the cluster-flies are often subject to a fungus 

 disease, which kills many of them. This fungus has been 

 determined by Thaxter as Empusa americana. 



THE BITING HOUSE-FLY 



Stomoxys calcitrans 



This fly is commonly known as the stable-fly, but as it 

 frequents houses, bites severely, and is often mistaken 

 for the house-fly, it may well be called the biting house- 

 fly. Because of the mistaken identity between this fly 

 and the common house-fly the popular fallacy that the 

 latter can bite has arisen. The biting house-fly is slightly 

 larger and more robust than the house-fly and has an 

 awl-like proboscis (Fig. 16) with which it can pierce the 

 flesh and cause severe irritation. It will bite through 

 stockings, and is very annoying, sometimes, by biting 

 one's ankles, especially when low shoes are worn. 



Habits and life history. This is normally an out- 

 door insect, but it frequently seeks the shelter of houses, 

 especially just before storms and has, therefore, been 

 called the "storm-fly." Other flies, however, have the 



