The injuries eansed by mites are arranged in two classes: injuries to man and domestic animals, and injuries to cultivated plants and stored food. The most notable of the former (lass are the ticks. The famous miana bug of Persia is a tick of the genus which inhabits houses, and the early travelers in those regions declared that its bite or puncture would produce convulsions, delirium, and even death. Specimens kept in Europe, however, have proved to be comparatively harmless. The moubata bug of Africa is a similar tick with a similar reputa tion. An allied species, the chicken-tick (Argus miniat“), does considerable damage to poultry in the Southern States. The cattle-tick (Bo6philns Loris) is the most injurious of all mites, as it occurs in nearly all warm countries, and is the means of spreading the Texas or Southern cattle fever. The itch-mites that cause a disgusting scaling of the skin were formerly not uncommon, but modern cleanliness has largely abolished them in the case of man. A species known as the sheep seah-mite (Psoroptes raminunis) 'is the cause of much injury to sheep, both in flesh and The red spider (Tetranychus) is a peren nial source of trouble to greenhouse and (Nut door plants, while the 'clover-mite' is a pest of fruit trees in the \Vest, and a related form (Stignm-us) injures pineapples in Florida. To
the family of cheese or flour mites (Tyro glyphi(he) belong a number of injurious species. 'Flue true cheese or dour mites (Tyroglyphus and -\leu'obiusl feed on a groat variety of stored products: cheese, flour, hams. cereals, drugs, seeds, and dried fruits. Although they are very small. they multiply so rapidly that attacked materials are completely overrun with them in a few days. Sono- species infest mushrooms and are a serious hindrance to their cultivation. The bulb-mite, or euchoris-mite ( llhizoglyphus), bur rows within bulbs and the roots of plants, there by giving entrance to destruetive fungi; the bulbs of lilies and orchids arc particularly subjeet in their ravages. A few of gall-mites arc of great veonomie importance, especially the pear leaf bhisteemite pyri), which is a notorious enemy of pear vulture in the United States. species of Tarsoneinida% living in enormous numbers in the heads of grasses, are kown to cause a whitening of the grass, called Comtparativel• few mites are beneficial to man. One of the harvest-mites is known to destroy the eggs of grasshoppers, and species of Cheyleties prey on the flour-mites and other in jurious forms. Several species have been found feeding on seale-insi-ets•