Rosa. Rose. Rosa canina, dog rose, wild brier, hip tree. Rosa centifolia. Rosa damascena.

Preparations: Rose water - Stronger rose water

Rosa.—Of the genus rosa at least four species have been, and probably to some extent are still, use in medicine—namely, Rosa canina L., Rosa centifolia L., Rosa damascena Mill., and Rosa gallica L.

Rosa canina.—The Dog Rose, Wild Brier, or Hip Tree, of Europe, is distinguished by its prickly stem and petioles, and ovate, smooth, rigid leaves. It has white or pale red flowers, having usually five obcordate fragrant petals. The fruit consists of a fleshy, hollow receptacle, bearing on its inner surface a number of hairy achenes. The ripe fruit, which is usually employed in the fresh condition, is ovoid, smooth, shiny and of a reddish color. The summit is crowned with 5-calyx teeth. Rose hips possess a pleasant, sweet, acidulous taste. It was formerly official in the British Pharmacopoeia under the name of Rosae Caninae Fructus. It contains about 30 per cent. of sugar, combined with citric and malic acids, also salts of these acids, and a trace of tannin. It was used for the preparation of an acidulous confection. Vanillin has also been found present in the petals.

Rosa centifolia has prickly stems and the leaves consist of two or three pairs of leaflets, with an odd one at the summit, closely attached to the common footstalk, which is rough, but without spines. The leaflets are ovate, broad, serrate, pointed, and hairy on the under surface. The flowers are large, with many petals, generally of a pale red color, and supported upon peduncles beset with short bristly hairs. The varieties of R. centifolia, produced by its almost universal cultivation, are very numerous, but the plant is said to grow with single flowers in the eastern part of the Caucasus. It is very closely allied to R. gallica, some botanists maintaining that the species are really one. The petals, which were recognized by the U. S. P., 1890, as pale rose, are roundish-obovate and refuse, or obcordate, pink, fragrant, sweetish, slightly bitter, and faintly astringent. They contain volatile oil, malic and tartaric acids, tannin, fat, resin, sugar, and a coloring matter which seems to be identical with that of the red rose. They should be collected when the flower is fully expanded but has not begun to fall. Their fragrance is impaired but not lost by drying. They may be preserved for a considerable time by compressing them with alternate layers of common salt in a well-closed vessel, or beating them with twice their weight of that substance. A rose water is often prepared from them by distillation.

Rosa damascena is not known in the wild state, and is thought by some botanists to have been produced by cultivation by hybridizing R. gallica with R. canina. It is the rose which is cultivated in Turkey and yields the commercial otto of rose. (See Oleum Rosae, p. 870.) It is a tall shrub with semi-double, light red to white flowers of moderate size, having several on a branch, though not clustered. Its volatile oil is the base of rose water.

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