INSECTS 



insect that inflicts the bite is not the house fly, but another 

 species closely resembling the common domestic fly in gen- 

 eral appearance, though a little smaller. If the culprit is 

 caught, there may be seen projecting from its head a long, 

 hard, tapering beak (Fig. 184, Prb), an organ quite differ- 

 ent from any part of the mouth equipment of the true 

 house fly (Fig. 183). This biting fly is, in fact, the stable 

 Jlv, a species known to entomologists as Stomoxys calci- 

 trans. It belongs to the same family as the house fly, and 

 while it sometimes comes about houses, it is particularly 

 a pest of horses and cattle. 



The stable fly lives in most parts of the inhabited world. 

 Both sexes have blood-sucking habits, and probably feed 

 on any kind of warm-blooded animal, though the species 

 is most familiar as a frequenter of stables and as a pest 

 of domestic stock. The stable fly breeds mostly in fer- 

 menting vegetable matter, the larvae being found prin- 

 cipally under piles of wet straw, hay, alfalfa, grain, weeds, 

 or any vegetable refuse. 



Cattle are afflicted by another pestiferous fly called 

 the horn fly, or Haematobia irritans. The species gets its 

 common name from the fact that it is usually observed 

 about the bases of the horns of cattle, where great numbers 

 of individuals often assemble. But the horns of the 

 animals are merely convenient resting places. Haematobia 

 is a biting fly like Stomoxys, and, because of its greater 

 numbers, it often becomes a most serious pest of cattle. 

 Through irritation and annoyance during feeding, it may 

 cause loss of flesh in grazing stock, and a reduction of milk 

 in dairy cows. The horn fly resembles the stable fly, but is 

 smaller, being about one-half the size of the house fly. It 

 breeds mostly in fresh manure of cattle dropped in the 

 fields. 



Of all the biting flies there is none to compare with 

 the tsetse fly of Africa (Fig. 185). Not only is this fly an 

 intolerable nuisance to men and animals because of the 

 severity of its bite, but it is a deadly menace by reason of 



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