Spec. Plant. Willd. ii. 440. Cl. 8. Ord. 3. Octandria Trigynia. Nat. ord. Polygonaceae. G. 3. Corolla five-parted, calycine. Seed one, angular. * * Bistorts, with a single spike.

Species 3. P. Bistorta.1 Great Bistort or Snakeweed. Med. . Bot. 3d edit. 668. t. 232. Smithy Flora Brit. 427. Eng. Bot.

t. 509. Officinal. Polygoni Bistorti radix, Edin.Dub. Bistort root.

Syn. Bistorte (F.), Natter-Wurzel (G.), Natter-Wortel (Dutch), Bistorta (I. S. Port.), Slangeort (Dan.), Sertechnaja trawa (Russ.).

This plant grows in many parts of Europe, Siberia, and Japan, and is indigenous to Great Britain; found generally in moist meadows, flowering in May and June.2 The root is perennial, woody, and tortuous: the stem rises nearly two feet in height, is foliaceous, jointed, swelling at the joints, solid, smooth, and bending a little near the top: the leaves are ovate, those next the root cordato-lanceolate: the whole are entire, waved at the edge, veined, of a fine green colour on the upper surface, and glaucous below; the radical ones are on long, winged footstalks, those of the stem almost sessile, amplexicaule, and sheathing. The flowers are small, of a pale rose-colour, collected into a close, oblong, terminal spike, an inch and a half long; the single flowers standing on short white flower-stalks, which rise in pairs from membranous, withering, floral leaves. The corolla is divided into five obtuse segments, with nectareous glands at the base: the filaments are longer than the corolla, tapering, and supporting purple anthers; and the germen is triangular, of a red colour, crowned with three long styles, with small round stigmas.

The seeds are three-sided, of a dark brown colour, and shining.

Qualities,-The dried root is inodorous, and has a very austere taste. Water extracts its virtues. The decoction strikes a deep black with persulphate of iron, and precipitates gelatine. It contains a large proportion of tannin, some gallic acid, and much starch.

Medical properties and uses.-The root of bistort is astringent and tonic. It is employed in haemorrhages, obstinate fluxes, leucorrhoea, and all diseases in which simple astringents are indicated. It has also been given in intermittents, combined with gentian, or acorus calamus. Externally, a strong decoction of it is a useful lotion for spongy gums and ill-conditioned ulcers. But it is almost discarded from modern practice.1

1 Bistorta, quasi bis torta, twice twisted.-Alston, Mat. Med. vol. i. 399.

2 It is, however, not confined to low situations, being found on the Carpathian Alps, vegetating under pinus magnus, at an elevation of 4476 feet. Vide Wah-lenberg's Flora Carpatorum.

The dose of the powdered root is from grs. xv. to 3 j., twice or thrice a day.