Large or medium-sized flies with thick-set body, large broad head, flat abdomen, and strong legs. The proboscis is less developed in the male, which lives merely on plant juices, than in the blood-sucking female. The cylindrical whitish larvæ live in earth, and are harmless. But the female insects bite human beings, and the larger kind attack horses and cattle in such a manner that blood-drops may be seen on the ground under the animals attacked, if these remain for a time in the same spot. There belong to this family: 1. The =Breeze Flies= (_Tabanus_), large insects up to ⅘ inch long, which are seen flying about with a buzzing sound over meadows and fields in the sunshine (=Ox Fly= = _T. bovinus_; =Horse Fly= = _T. autumnalis_). 2. The =Lesser Breeze Flies= (_Hæmatopota_), smaller and more slender, with grey wings, bite most before a storm and in hot sultry days. 3. The =Blinding Breeze Flies= (_Chrysops_), as large as the Lesser Breeze Flies, but broader, with shining golden-green eyes and wings marked with black. _Remedies_: Compare p. 165, and above; draining the soil, however, is no good here. Family: =Muscidæ= (_True Flies_). These are flies with three-jointed antennæ, constructed on the type seen in the common house fly. Here are included the =Caterpillar Flies= (_Tachina_), the =Flesh Flies= (_Sarcophaga_), =Common Flies= (_Musca_), =Flower Flies= (_Anthomyia_), =Green-eyed Flies= (_Chlorops_), etc. The =Caterpillar Flies= (_Tachina_) are black, grey, or reddish yellow flies, reminding one by their appearance of the common house fly or the blue-bottle. They play the same part in the economy of nature as the sand wasps (p. 129), but always lay their eggs externally on the skin of the host; the maggots consequently never prey on those insect larvæ which live in the tissues of plants or in the soil. [Illustration: FIG. 115.—Caterpillar Fly (_Tachina fera_). ] The =Flesh Flies= (_Sarcophaga_) have a longish abdomen, with large bristles on the hinder margins of the segments. Thorax with three longitudinal streaks. The flies suck up sweat, but do not bite. The eggs develop within the abdomen of the mother; the flies lay the young larvæ in dead flesh; also, if not kept clean, in wounds of human beings and animals,—sometimes, too, in the genital opening of horses, cattle, and swine, in which case the maggots live as true parasites in the vagina and uterus, causing a secretion of mucus, upon which they live. Two to three generations yearly; fifty to eighty maggots each time. _Remedies_: On keeping the flies from cattle, cf. p. 165; to keep them from meat, flynets, a gauze cover. =Blow Fly= (_S. carnaria_), with black speckled abdomen. The =Common Flies= (_Musca_)