in botany; a genus of the order of fungi, belonging to the cryptogamia clas of plants. There are ten species, of which the following are the most remarkable. 1. The tuber, truffles, or subterraneous puff-balls, is a native of woods both in Scotland and England. It is a subterraneous fungus, growing generally in clusters three or four inches under ground, without any visible root. The figure of it is nearly spherical, the size that of a potatoe; the exterior coat at first white, afterwards black, and studded with pyramidal or polyhedrous tubercles; the internal substance solid and callous, of a dirty-white or pale-brown colour, grain'd like a nutmeg with serpentine lines; in which, according to Micheli, are imbedded minute oval capsules, containing each from two to four round warted seeds. The truffles of Great Britain seldom exceed three or four ounces in weight; but in Italy, and some other parts of the continent, they are said to have been found of the enormous size of eight and even 14 pounds. They are received at our tables, either fresh and roasted like potatoes, or dried and sliced into ragouts. They have a volatile and somewhat urinous smell, and are reputed to be aphrodisiacal. Dogs are with much pains taught to hunt for them by the scent, and to scratch up the ground under which they lie.

2. The bovita, or common puff-ball, is frequent in meadows and pastures in the autumn. It varies exceedingly in size, figure, superficies, and colour. In general, it consists of a sack or bag, having a root at its base, and the bag composed of three membranes, an epidermis, a tough white skin, and an interior coat which adheres closely to the central pith. The pith in the young plants is of a yellowish colour, at first firm and solid, but soon changes into a cellular spongy substance, full of a dark dull-green powder, which discharges itself through an aperture at the top of the fungus, which aperture is formed of laceraed segments, in some varieties reflexed. The powder is believed to be the seeds, which through a microscope appear of a spherical form, and to be annexed to elastic hairs. See Haller's Hist. Helvet. n. 2172.

Among the numerous varieties of this fungus, the clavatum is most remarkable. It is a smooth sessile kind, of a nearly spherical form, puckered or contracted at the root. This sometimes grows to an enormous size. It has been found in England as big as a man's head; and at Carraria, near Padua in Italy, specimens have been gathered, weighing 25 pounds, and measuring two yards in circumference: but its more ordinary size is that of a walnut or an apple.

The varieties of this species have no limits, being frequently found to run into one another; the scaly, warty, and echinated coats turning smooth as the plants grow old, and the neck of the fungus having no determinate length. The natural colour of the puff-ball is either white, grey, or ash-coloured: but it is sometimes found yellowish, tawny, and brownish. The internal spongy part of it, bound on to wounds, is esteemed good to stop bleedings. Pressed and dried in an oven, the puff-ball becomes a kind of tinder, the smoke of which is said to intoxicate bees. See Gent. Mag. July 1766. The Italians fry the great variety, and indeed any of the others when young, and eat them with salt and oil, according to the relation of Marigli.

LYCOPODIUM, or club-moss; a genus of the order of musci, belonging to the cryptogamia clas of plants. There are 24 species; of which the following are the most remarkable. 1. The clavatum, or common club-moss, is common in dry and mountainous places, and in fir forests. The stalk is prostrate, branched, and creeping, from a foot to two or three yards long; the radicles woody. The leaves are numerous, narrow, lanceolate, acute, often incurved at the extremity, terminated with a long white hair, and every where surround the stalk. The peduncles are erect, firm, and naked (except being thinly set with lanceolate scales), and arise from the ends of the branches. They are generally two or three inches long, and terminated with two cylindrical yellowish spikes, imbricated with oval-acute scales, finely lacerated on the edges, and ending with a hair. In the ala or bosom of each scale is a kidney shaped capsule, which bursts with elasticity when ripe, and throws out a light yellow powder, which, blown into the flame of a candle, flashes with a small explosion. The Swedes make mats of this moss to rub their shoes upon. In Russia, and some other countries, the powder of the capsules is used in medicine to heal galls in children, chaps in the skin, and other sores. It is also used to powder over officinal pills, and to make artificial lightning at theatres. The Poles make a decoction of the plant, and, dipping a linen cloth into it, apply it to the heads of persons afflicted with the disease called the plica polonica, which is said to be cured by this kind of fomentation.

2. The selago, or fir club-moss, is common in the Highland mountains of Scotland, and in the Hebrides. The stalk at the base is single and reclining; but a little higher is divided into upright dichotomous branches, from two to six inches high, surrounded with eight longitudinal oblique series of lanceolate, smooth, rigid, imbricated leaves. Near the summits of the branches, in the ala of the leaves, are placed single kidney-shaped capsules, consisting of two valves, which open horizontally like the shells of an oyster, and cast out a fine yellow powder. These capsules Linnaeus supposes to be antherae, or male parts of fructification. In the ala also of many of the leaves, near the tops of the branches, are often found what the same great author calls female flowers, but which the ingenious Haller esteems to be only gems or buds of a future plant. They consist, first, of four stiff, lanceolate, incurved, minute leaves, one of the outermost longer and larger than the rest. These are supposed to correspond to the calyx in regular flowers. Again, at the bottom of this calyx, are five small pelucid substances resembling leaves, visible only by a microscope, which are supposed analogous to pistils. These, in time, grow up into three large broad leaves, Lyconphron two of the five united together like the hoof of an ox; with a third narrower one annexed at the base, and two other minute ones opposite to the other three. These five leaves are joined at the base; and in autumn, falling from the cayx, vegetate, and produce a new plant. See a dissertation De seminibus mycorum, Amoenit. Academ. II. p. 261. In the island of Ranfay, near Sky, in Rossshire, and some other places, the inhabitants make use of this plant instead of alum, to fix the colours in dyeing. The Highlanders also sometimes take an infusion of it as an emetic and cathartic; but it operates violently; and, unless taken in a small dose, brings on giddiness and convulsions. Linnaeus informs us, that the Swedes use a decoction of it to destroy lice on swine and other animals.