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. ?84, Prb), an organ quite differ- ent from any part of the mouth equipment of the true house fly (Fig. ?83). This biting fly is, in fact, the stable ff.v, a species known to entomologists as Stomoxvs calci- trans. It belongs to the same family as the housefly, 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 o( the horns ofcattle, where great numbers of individuals often assemble. But the horns of the animais 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 animais because of the severity of its bite, but it is a deadly menace by reason of
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MOSQUITOES
