Birthwort: a plant with heart-shaped leaves set alternately on the stalks; in the bo-soms of which come forth irregular tubulous flowers, with a wide mouth, whose lower part is produced into a long flap like a tongue: the seed-vessel is large, roundish, and divided into six cells.

1. Aristolochia long a Linn. Aristolochia longa vera C. B. Long birthwort, with uncut leaves, (landing on pedicles; and oblong roots, not tapering to a point, brownish on the outside and yellow within.

2. Aristolochia rotunda Linn. Aristolochia rotunda flore ex purpura nigro C. B. Round birthwort: with uncut leaves joined immediately to the stalks, and roundish roots.

3. Pistolochia: Aristolochia tenuis Pharm. Paris. Aristolochia pistolochia dicta C. B. & Linn.

Bushy birthwort: with indented leaves set on pedicles; and bushy roots, composed of a number of fibres issuing from one head. In this and the foregoing sorts, the stalks are weak and trailing, and the flowers stand solitary.

4. Aristolochia tenuis Pharm. Edinb. Aristolochia clematitis recta C. B. Aristolochia clematitis Linn. Creeping birthwort: with upright stalks, flowers standing in clusters, and long slender creeping roots rarely exceeding the thickness of a goose quill.

These plants are natives of the southern parts of Europe, from whence we are supplied with the dry roots. They bear the colds of our own climate; the third sort excepted, which dies in severe winters. The fourth spreads saft, to a great distance, so as not to be easily extirpated.

All the birthwort roots have somewhat of an aromatic smell, and a warm bitterifh taste. They are represented by authors, as being extremely hot and pungent: Boerhaave says, they are the hottest of the aromatic plants, and, as it were, burn the tongue and palate, having probably examined the fresh roots; but whatever their qualities may be in that state, such as are usually met with in the shops, have no great pungency. The long and round sorts, on first chewing, scarce discover any taste, but in a little time prove nauseously bitterish; the round somewhat the most so. The other two instantly fill the mouth with a kind of aromatic bitterness, not very ungrateful.

These roots give out their virtue by infusion both to spirituous and watery menstrua, to the first most perfectly: the colour of all the tinctures cures is brownish or yellowish. In distillation, pure spirit brings over little or nothing: with water there arises, at least from both the slender rooted sorts, a small portion of essential oil, pos-sessing the smell and flavour of the roots. The extracts made with spirit smell moderately, and taste strongly, of the birch worts: the watery extracts have nothing of their peculiar flavour, and are much more nauseous in taste than either the spirituous extracts, or the roots in substance. The birthwort roots are celebrated as warm attenuants and deobstruents, particularly in sup-pressions of the uterine purgations, from which virtue they are suppofed to have received their name: the dose is from a scruple to a dram and upwards. They have likewise been recommended, particularly the fourth sort, as alterants in the gout: Boerhaave observes, that the pitui-tous gout, as he calls it, is often relieved by an infusion of these roots in spirit of juniper berries, sweetened with sugar, and taken to the quantity of a spoonful at a time; but that in other kinds of the gout, and in subjects of a tender consti-tution, this medicine occasions a loss of appetite, a weakness of the stomach, and a languidness, less supportable than the gout itself. A powder composed of this and other similar materials, which was prescribed by the ancients as an anti-arthritic, and has lately come again into esteem, has also produced complaints of the same kind. Externally these roots have been used as difcuti-ents, detergents, and antiseptics: Simon Paulli relates, that the long birthwort roots, applied as an epithem or in somentation, were found remarkably serviceable in stubborn ulcers of the legs.