Chimaphila. N. F. IV (U. S. P. VIII). Pipsissewa. Prince's Pine. Wintergreen. Bitter Wintergreen. King's Cure. Ground Holly. Love-in-winter. Rheumatism Weed. Herbe de Pyrole ombellee, Fr. Doldenblüthiges Harnkraut, Wintergrün, G.—There are two American species, the official variety being described by the N. F. as " the dried leaves of Chimaphila umbellata (Linne) Barton (Fam. Ericacecae), without the presence of more than 5 per cent. of stems or other foreign matter." N. F. It is a small evergreen plant, with a perennial, creeping, yellowish rhizome, which gives rise to several simple, erect or semiprocumbent stems, from four to eight inches in height, and ligneous at their base. The leaves are "oblanceolate, from 2.5 to 7 cm. in length and from 8 to 20 mm. in breadth, the upper portion coarsely and sharply serrate, acute or somewhat obtuse, the lower wedge-shaped and nearly entire; coriaceous, smooth and uniformly dark green on the upper surface, paler beneath, the veins prominent. Odor slight; taste astringent and bitter. The powdered drug is brownish-green and, when examined under the microscope, exhibits characteristic epidermal tissue composed of cells with unevenly thickened, porous, and wavy vertical walls; the fragments from the lower epidermis show numerous broadly elliptical stomata up to 0.04 mm. in length, the epidermal tissue in transverse view shows outer walls from 0.008 to 0.015 mm. in thickness; fragments of palisade and mesophyll tissue containing chloroplastids; tracheae with spiral or annular markings; a few characteristic, elongated trachea-like cells, about 0.014 mm. in width, thick-walled, slightly lignified and with minute, double-spiral bands or delicate reticulations; fragments of the epidermis from the stems and root-stocks, the cells containing a purplish coloring substance which is intensified when the powder is mounted in hydrated chloral T.S.; parenchyma cells containing a reddish-brown amorphous substance; calcium oxalate in rosette aggregates mostly about 0.035 mm. in diameter, occasionally up to 0.065 mm. in diameter; starch grains few, rounded, simple, up to 0.016 mm. in diameter and sometimes with a central cleft or fissure, or two- to four-compound; trichomes absent. Chimaphila yields not more than 7 per cent. of ash." N. F.

The leaves are short petiolate, occurring in irregular whorls, of which there are usually two on the same stem. The flowers are disposed in a small terminal corymb, and stand upon nodding peduncles. It is found in the Northern latitudes of Europe and Asia, also in dry woods from Nova Scotia to Georgia and westward to the Pacific. The flowers appear in June and July.

C. maculata, (L.) Pursh., or spotted wintergreen, though not official, probably possesses similar virtues. The character of the leaves of the two plants will serve to distinguish them. Those of C. maculata, are lanceolate, rounded at the base, where they are broader than near the summit, and of a deep olive green, veined with greenish-white; the leaves of C. umbellata are broadest near the summit, gradually narrowing to the base, and of a uniform shining green color.

Pipsissewa, when fresh and bruised, exhales a peculiar odor. Boiling water extracts the active properties of the plant, which are also imparted to alcohol. Fairbank found in the leaves a peculiar substance which he calls chimaphilin.

Chimaphilin was obtained by extracting the tincture with chloroform, or by distilling the sterna with water. It occurs in golden-yellow auricular crystals, odorless and tasteless, practically insoluble in water, but dissolving in alcohol, ether, chloroform, and the fixed oils. It is possessed of neither acid nor alkaline properties. Peacock (A. J. P., 1892, p. 295) found that chimaphilin has the chemical composition C24H21O4.

Ridenour (A. J. P., 1895, p. 236) confirms the formula, C24H21O4, given by Peacock. He finds the melting point of the purified chimaphilin to be 114° C. (237.2° F.). He also prepared another crystalline principle melting above 250° C. (482° F.), to which he gives the formula C10H19O, which agrees with Beshore's product. Arbutin, C12H16O7, is also found in chimaphila.

This plant is stated to have been used internally by the North American Indians in scrofula and rheumatism, and was a popular remedy among the settlers of this country. It has no medicinal properties, however, beyond a feeble diuretic action and perhaps some antiseptic influence on the urine. It is occasionally prescribed for cystitis. The best preparation is the fluidextract, which may readily be made into a syrup. Dose, thirty to ninety grains (2-6 Gm.).

The Dispensatory of the United States of America, 1918, was edited by Joseph P. Remington, Horatio C. Wood and others.