1 Spec. Plant, Willd. iv. 151. Cl. 20. Ord. 4. Gynandria Hexandria, Nat. ord. Aristolochiaceae. G. 1609. Cor. of one petal, strap-shaped, ventricose at the base.

Cap. six-celled, inferior, containing many seeds. Stem twining, frutescent. Species 27. A. Serpentaria. Virginia Snake-root, or Birthwort.

Med. Bot. 3d edit. 152. t. 59. Veg. Mat. Med. of the United

States, pl. 25.

1 The

Dioscoridis gives name to the genus, but is not the officinal plant, which was introduced only since the settlement of Europeans in America. The name is derived from some supposed virtue of cleansing the lochia after child-bearing; thence the English name Birthwort.

Officinal, Serpentaria, Lond. Serpentariae radix, Edin. Aristolochia Serpentaria; radix, Dub. Serpentaria Root.

Syn. Serpentaire (F.), Virginische Schangenwurzel (G.), Skngelwortel (Dutch), Slangrod (Danish), Ormrot (Swed.), Serpentaria de Virginia (I. S Por.).

This plant is a native of North America, from Pennsylvania to Florida; flowering in May and June, and ripening its seeds in September. The root is perennial, consisting of bundles of fibres, of a yellow-ochre colour, which changes to brown on drying, attached to a contorted horizontal caudex; from which several stems rise about 10 inches in height, slender, crooked, and jointed; supporting on long foot-stalks at each knot, thin, cordate, entire, pointed, trinerved leaves, of a yellowish-green colour. The flowers proceed from the joints near the root, and stand upon long sheathed articulated peduncles, which bend down and almost bury the flowers beneath the decayed leaves near the roots.1 There is no calyx: the corolla is of a brownish purple colour, globular at the base, contracted and bent in the middle, and terminating in a triangular lip. The anthers are sessile, attached to the under-side of the stigma, which is roundish, divided into six parts, and almost sessile, rising from an oblong, angular, hairy, inferior germen.

The seeds are flat, and contained in a six-celled hexagonal capsule.

Dried serpentaria root is imported into this country in bales, each containing from two to five hundred weight. It is frequently mixed with the roots of Collinsonia praecox.

Qualitiess-The dried root has an aromatic odour, not unlike that of valerian; and a sharp, warm, bitter, pungent taste, resembling, in some degree, that of camphor. Water extracts all the sensible qualities of the root, affording a yellowish-brown infusion, which is not altered by sulphate of iron or zinc, nitrate of silver, bichloride of mercury, tartarized antimony, the mineral acids, and the alkalies, nor is it precipitated by gelatine or tannin. The acetate of lead throws down a flocculent precipitate, which is not soluble in acetic acid, showing the presence of mucus. With alcohol, it affords a bright greenish tincture, which is rendered turbid by the addition of water. According to Bucholz, the components of serpentaria are, volatile oil, 5; yellow gum-resin, 28 1/2; extractive, 17; gummy extract, 181; woody fibre, 624; and water, 144 1/2, in 1000 parts. The active principles of serpentaria, therefore, appear to reside in a bitter resin and a volatile oil.

1 Some of the species of Aristolochia, in South America, have flowers large enough to serve as bonnets for children.

Medical properties and uses.-Serpentaria root is a stimulating diaphoretic and tonic. It is beneficially employed in typhoid and putrid fevers, whether idiopathic, or accompanying the exanthemata, to excite diaphoresis, and support the powers of the system; and is found frequently to increase the efficacy of Cinchona in removing protracted intermittents. It is also an excellent remedy in dyspepsia, particularly when the skin is dry and parched; and is sometimes used as a gargle in putrid sore throat. On account of its stimulant properties, it is contra-indicated in the inflammatory diathesis; and, previous to its exhibition, the bowels should be well evacuated.

It may be given in substance, or in infusion made by macerating j. of the bruised root in f xij. of boiling water, in a covered vessel for two hours, and straining. Decoction is a bad form of preparation of Serpentaria, as the boiling dissipates the volatile oil, on which much of the virtue of the remedy depends. The dose of the powdered root is grs. x. increased to 3ss.; that of the infusion, f jss to f ij., given every fourth hour.

Officinal preparations. Infusum Serpentaria L. Tinctura Serpentarice, L. E. D. Tinctura Cinchonce composita, L. D. Electuarium opiatum, E.