NETTLE (0. Eng. netele, cf. Ger. Nessel)  , the English equivalent of Lat . Urtica, a genus of plants which gives its name to the natural order Urticaceae . It contains about thirty species in the temperate parts of both east and west hemispheres . They are herbs covered with stinging hairs; and with unisexual flowers on the same or on different plants . The male flowers consist of a perianth of four greenish segments enclosing as many stamens, which latter, when freed from the restraint exercised upon them by the perianth-segments while still in the bud, suddenly uncoil themselves, and in so doing liberate the pollen . The female perianth is similar, but encloses only a single seed-vessel with a solitary seed . The stinging hairs consist of a bulbous reservoir filled with. acrid fluid, prolonged into a long slender tube, the extremity of which is finely pointed . By this point the hair penetrates the skin and discharges its irritant contents beneath the surface . Nettle tops, or the very young shoots of the nettle, may be used as a vegetable like spinach; but from the abundance of crystals (cystoliths) they contain they are apt to be gritty, though esteemed for their antiscorbutic properties, which they do not possess in any exceptional degree . The fibre furnished by the stems of several species is used for cordage or paper-making . Three species of nettle are wild in the British Isles: Urtica dioica, the common stinging nettle, which is a hairy perennial with staminate and pistillate flowers in distinct plants; U. urens, which is annual and, except for the stinging hairs, glabrous, and has staminate and pistillate flowers in the same panicle; and U. pilulifera (Roman nettle), an annual with the pistillate flowers in rounded heads, which occurs in waste places in the east of England, chiefly near the sea—the more virulent of the British species . From their general presence in the neighbourhood of houses, or in spots where house refuse is deposited, it has been suggested that the nettles are not really natives, a supposition that to some extent receives countenance from the circumstance that the young shoots are very sensitive to frost .

In any

case they follow man in his migrations, and by their presence usually indicate a soil rich in nitrogen . The trailing subterranean root-stock renders the common nettle somewhat difficult of extirpation . NEPI'LERASH, or URTICARIA, a disorder of the skin characterized by an eruption resembling the effect produced by the sting of a nettle, namely, raised red or red and white patches occurring in parts or over the whole of the surface of the body and attended with great irritation . It may be acute or chronic . In the former variety the attack often comes on after indulgence in certain articles of diet, particularly various kinds of fruit, shell-fish, cheese, pastry, &c., also occasionally from the use of certain drugs, such as henbane, copaiba, cubebs, turpentine, &c . There is at first considerable f everishness and constitutional disturbance, together with sickness and faintness, which either precede or accompany the appearance of the rash . The eruption may appear on any part of the body, but is most common on the face and trunk . The attack may pass off in a few hours, or may last for several days, the eruption continuing to come out in successive patches . The chronic variety lasts with interruptions for a length of time often extending to months or years . This form of the disease occurs independently of errors in diet, and is not attended with the feverish symptoms characterizing the acute attack . As regards treatment, the acute variety generally yields quickly to a purgative and the use of some antacid, such as magnesia or liquor potassae . The local irritation is allayed by sponging with a warm alkaline solution (soda, potash or ammonia), or a solution of acetate of lead, and a lotion of ichthyol has been found useful .

Chronic cases have been known to benefit from the

administration of creosote or salol .