in botany: A genus of plants of the class of monocotyledons, and order of tetrandria; and in the natural system classified under the 53rd order, Scabridae. The small flower has a calyx of four leaves; no corolla; a staminate minute, central, urn-shaped. The female a bivalve calyx; and a single, oval, glossy seed. There are 28 species; three of which are British plants.

1. The pilosifera, Roman nettle, has a stalk branched, two or three feet high. Leaves opposite, oval, serrated, ringed. Fruit globose.

2. The urtica, less flinging nettle, has a stem a foot high. Leaves roundish, deeply serrated, opposite, burning. The stings are very curious microscopic objects: they consist of an exceedingly fine pointed, tapering, hollow substance, with a perforation at the point, and a bag at the base. When the spring is pressed upon, it readily perforates the skin, and at the same time forces up some of the acrimonious liquor contained in the bag into the wound.

3. The dioica, common nettle, has a square firm stem, three or four feet high. Leaves heart-shaped, long-pointed, serrated, beset with stings. Flowers in long catkins. The aculei, or stings of the nettle, have a small bladder at their base full of a burning corrosive liquor: when touched, they excite a blister, attended with a violent itching pain, though the sting does not appear to be tubular, or perforated at the top, nor any visible liquor to be infused into the puncture made by it in the flesh. It seems certain, however, that some of this liquor is infused into the wound, though invisibly, since the stings of the dried plant excite no pain.

Nettle-tops in the spring are often boiled and eaten by the common people instead of cabbage-greens.

In Arran, and other islands, a tennet is made of a strong decoction of nettles: a quart of salt is put to three pints of the decoction, and bottled up for use. A common spoonful of this liquor will coagulate a large bowl of milk very readily and agreeably. The stalks of nettles are so like in quality to hemp, that in some parts of Europe and Siberia they have been manufactured into cloth, and paper has been made of them. The whole plant, particularly the root, is esteemed to be diuretic, and has been recommended in the jaundice and nephritic complaints. It is also reckoned astringent; and of service in all kinds of hemorrhages, but is at present but little in practice. The roots boiled will dye yarn of a yellow colour. The larva, or caterpillars of many species of butterflies, feed on the green plant; and sheep and oxen will readily eat the dried.

URTICA Marina. See ANIMAL-Flower.