Rubus. Blackberry bark, Bramble. Rubus villosus, Rubus nigrobaccus, Rubus cuneifolius.

Rubus. N. F. IV. Blackberry Bark. Bramble. Finger Berry, Ecorce de Ronce Noir, Fr. Brambeeren, Brombeerrinde, G.—"The dried bark of the rhizome of Rubus villosus Aiton, Rubus nigrobaccus Bailey, or of Rubus cuneifolius Pursh (Fam. Rosaceae)." N. F. Of the genus Rubus a large number of species are indigenous in the United States, where they are called by the various names of blackberry, dewberry, cloudberry, etc. Most of them are shrubby or suffruticose briers, with astringent roots and edible berries; some have annual stems without prickles. They are naturally divided into the raspberries, in which the edible fruit is composed of pulpy, one-seeded, coherent little drupes, separate from the dry receptacle, and the blackberries, in which the receptacle is juicy and coheres with the drupes to form the fruit. The National Formulary recognizes as the source of rubus only three species, but it is probable that others contribute to the bark of the markets. In fact, the U. S. Pharmacopoeia of 1890 recognized officially R. canadensis L., and R. trivialis Michaux.

The blackberry root is branching, cylindrical from 0.5 to 2.5 cm. in thickness, and covered with a thin bark, which is externally of a light brownish or reddish-brown color, and in the dried root is wrinkled longitudinally. The dewberry root is usually smaller, without the longitudinal wrinkles, but with transverse fissures through the epidermis, and of a dark ash color, without any reddish tinge. Both are inodorous. The National Formulary IV describes blackberry bark as follows: "In elongated, tough, flexible quills or bands, from 3 to 6 mm. in diameter, the bark from 1 to 2 mm. in thickness; outer surface deep red-brown or dark gray-brown, occasionally blackish-brown, somewhat scaly; inner surface yellow or pale brown, strongly and coarsely long straight-striate; fracture tough-fibrous; readily splitting. Inodorous; taste strongly astringent and bitter. Rubus yields not more than 5 per cent. of ash." N. F. Blackberry bark was official in the U. S. VIII, but it was deleted, and the National Formulary IV admitted it under the name of Rubus. Its virtues are extracted by boiling water and by diluted alcohol, and depend chiefly upon tannin, which is an abundant constituent. The woody part of the roots is inert.

Dewberry and blackberry roots have long been a favorite domestic astringent remedy in diarrheas. Given in decoction, they are usually acceptable to the stomach, without being offensive to the taste. The decoction may be prepared by boiling an ounce of the smaller roots, or of the bark of the larger, in a pint and a half of water down to a pint, of which from one to two fluidounces (30 to 60 mils) may be given to an adult three or four times, or more frequently, during the twenty-four hours.

A fluidextract and compound elixir of rubus are in the N. F.

The fruit is official in the N. F. under the English title Blackberries, N. F. IV. Rubi Fructus. It is described by the N. F. as "The fresh, ripe fruit of varieties of Rubus nigrobaccus Bailey or Rubus villosus Alton (Fam. Rosaceae). An aggregate fruit, ovate to oblong, rounded or slightly pointed, composed of numerous, shining black drupelets attached to an esculent receptacle; pericarp externally smooth or with only a few hairs (R. villosus), mesocarps fleshy, juice purple-red, endocarps hard, black, surfaces deeply wrinkled." N. F.

The fruit of Rubus Idaeus is official in the N. F. under the English title Raspberries, N. F. IV. Rubi Idaei Fructus. They are described as "The fresh, ripe fruit of varieties of Rubus Idaeus Linné or of Rubus strigosus Michaux (Fam. Rosaceae). An aggregate fruit, globular or hemispherical with a concave depression at the base where separated from the receptacle, composed of twenty or more small, rounded-polygonal, succulent drupelets; pericarps externally red, hairs numerous; mesocarps fleshy, juice red; endocarps small stones with wrinkled surfaces. Odor characteristic, aromatic; taste pleasant, sweet, acidulous. For pharmaceutical purposes, Black Raspberries, the fresh ripe fruit of varieties of Rubus occidentalis Linné (Fam. Rosaceae), may be substituted either in part or wholly for Red Raspberries." N. F. Rubus strigosus has yielded to cultivation certain superior raspberries, especially those which have been known commercially as the Cuthbert and Hansall raspberries. Rubus neglectus Peck, the purple wild raspberry, with a fruit which varies from dark red or purple to yellowish in cultivation, has also yielded a commercial raspberry.

Raspberries are employed for the production of the N. F. syrup.

The Rubus occidentalis L., black raspberry or thimbleberry of the Northern United States, which is also cultivated, is sometimes employed for the making of a raspberry syrup, but yields a very inferior product.

Rubus Chamaemorus L. Cloud Berry. Baked-Apple Berry. (Fam. Rosaceae.)—This plant, which inhabits the northern portions of both continents, is largely employed in Northern Russia, in the form of an infusion of the berries or leaves, as a diuretic in dropsy. The fruits are about 2 cm. in diameter, of an amber color, and very juicy when ripe. Popoff found in it a crystallizable acid which is an essential diuretic, acting directly upon the renal secreting structures without affecting either cardiac action or arterial tension. (Vrach., iv, 1886.)

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