LOUSE (AS.. /fis.. Ce•. Lang. louse: perhaps connected with As. /(wg, 011G, truth.
lairs, empty, vain. AS. Gosh. liusan. O1IG. for-liosan• Ger. ver-lie•en, to lose, Lat. lucre, Gk. ?ago, lycin, to loose, destroy). A parasitic bug of the suborder Anoplu•a or Para sita, which contains the single family Pediculi the, dwelling on man and other animals. Lice are grayish-white, more or less transparent. com pressed. wingless insects, with fleshy blood-suck ing beaks. It is still not certain just how the blood is sucked up. Sebiiidte placed a louse on his hand and observed it under a lens while feed ing. noted alternate contractions and expan sions of parts of the alimentary tract, while the entire Iraqi, underwent peristaltic movements and vibrations from side to side. The number of known Ike is not large—about six genera and forty species are recorded. Different kinds of mammals are infested with different kinds of lice, even those mammals that live in water. Seals have a genus, Echinophthirius. Several species of the genus Pedieinus infest monkeys. Ele a louse (flamatomyzus probos•i dens) with a remarkably long proboscis. The louse of the horse (Menu/lc/pit:us asini), that of the pig (Ilumatopinus arias), and that of the cow (IDrmatopinus eurysternus) are the best known of those that dwell on domestic animals. Three species belong to man: one (Pediculus capi/is) is found on the bead; another (Pcdi calms restimenti) on the body, breeding in soiled clothing; and a third (Phthirius inguinalis) lives in the eyebrows, armpits, and the pubic region. Andrew Murray stated that the heads of different races of men are infested with different varieties of P•dienlus eapitis, basing his con clusions upon the collections made by Darwin.
Little is known concerning the development of lice. The eggs are fastened to the hair, and the young, although they molt several times, do not undergo metamorphosis. There is a disease called phthiriasis attributed to lice, but for aught that is really known the lice may be merely an accompaniment of the neglected and unclean condition which, Iwrhaps, is really the cause of the disease. Alpreurial ointment is generally recommended for use against the species affecting human beings. Cleanliness is the best preventive of lice on man and beast. To destroy them on domestic animals washing with infusions of soap suds, tobaceo, and kerosene is recommended. Various ointments composed of lard or tallow, in vhicli sulphur or zinc is mixed, are sometimes used. Wood ashes and Persian inseet-powder sprinkled plentifully in the hair or wool are also said to be ellieavions. Such washings and applica tions should be repeated several times at inter vals, and barns which contain infested animals should be thoroughly whitewashed.
The word is also used in eombinations stud] as 'bird-louse.' plant louse.' The plant-lice are Hemipt era, but belong to a different family, the Aphidithe (see Amur)) ; while the bird-liee be long to the Mallophaga (q.v.)—a distinct order of insects parasitic on birds. Consult Osborn, Inserts A ffecting Domestic Animals (Department of Agriculture. Washington, 1896).