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Rh themselves by plastering their huts, both floors and walls, with mud and cow-dung. The huts are also frequently smoked in order to drive the ticks from the thatch. A most valuable remedy for immediate use is the powder of the pyrethrum flower, which should be dusted between the sheets of the bed. Some protection may be obtained by keeping a lamp alight by the bedside throughout the night. In certain parts of Africa the distribution of O. moubata is overlapped by that of a closely allied species, O. savignyi, which is more diurnal in its habits and seems to have a predilection for market-places, cattle-stands, etc. O. savignyi differs from O. moubata in being provided with eyes, in having larger processes on the legs, and a more minutely pitted dorsal surface. O. savignyi has been recorded from Egypt, Nubia, Abyssinia, Somaliland, British East Africa, etc., as well as from southern Asia. It also may be concerned in the transmission of African relapsing fever or other disease. Its bite is dreaded by the natives. Argas persicus (Fischer), A. miniatus (Koch) (Plate VI., 4), has a flat, thin, oval body of a yellowish, greenish, or reddish colour, spotted on the back with a great many white granulations; the legs are pale yellow. Its distribution is cosmopolitan; it is found more commonly in the north and east of Persia, also in Syria, Turkestan, Russia, China, Algeria, and Cape Colony, in North and South America and the West Indies, West Australia, and Queensland. It attacks both poultry and human beings. Its habits are similar to those of Ornithodoros moubata; it infests old houses, living in the cracks of walls and floors. Kotzebue says that in Persia it may so infest villages as to drive out the inhabitants.