Spec. Plant. Willd. ii. 603. Cl. 10. Ord.l. Decandria Monogynia. Nat. ord. Ericaceae. G. 867. Calyx five-parted. Corolla nearly funnel-shaped. Stamens declined. Capsule five-celled.

1 The sulphate of M. Najni is said to be a sulphate of lime coloured by the colouring principle of the root.

2 Nouveaux Elem. de Therap. par Alibert, tome ii. p. 247.

3 Sir E. Home.

Species 7. R. chrysanthum. Golden-flowered Rhododendron.

Med. Bot. 2d edit. 299. t. 103. Pall. Ross. i. p. 44. t. 30. Officinal. Rhododendri chrysanthi folia, Edin. The leaves of Rhododendron.

Syn. Rosage (F.), Gelber Alpbalsam (G.), Rhododendro Aureo (I.), Sabina (Russ.), Kaschkara (Koibal), Scbei (Tartar).

This beautiful shrub is a native of the mountainous parts of Siberia, flowering in June and July. It rises a foot in height, and sends off spreading branches, which are covered with a brown bark. The leaves are terminal, oblong, ovate, and attenuated to the petiole; few, smooth, stiff, with the margin entire and bent in : the upper surface reticulated, rugged, and of a deep green colour; and the under ferruginous or glaucous. The flowers are large, yellow, and terminate the branches, forming umbels : the calyx is persistent; the corolla monope-talous, inclining, and regularly divided into five spreading segments: the filaments are slender, nearly as long as the corolla, supporting oval anthers; and the germen is pentagonal, bearing a long slender style, crowned with a five-lobed stigma. The capsule is ovate, somewhat angular; and contains many small grey irregular seeds, like sawdust.

Qualities.-The leaves of this plant are inodorous, and have an austere, astringent, bitterish taste. Water extracts their virtues either by infusion or decoction. Stolze procured oxidized extractive, soluble extractive, tannin, green wax, extractive obtained by potassa, and fibre in the dried leaves.

Medical properties and uses.-Yellow rhododendron leaves are stimulant, narcotic, and diaphoretic. When taken, they first increase the arterial action and the heat of the body, producing diaphoresis; and these effects, according to Dr. Home's observations, are followed by a proportional diminution of excitement; the pulse, in one case, having been reduced thirty-eight beats. In large doses they produce nausea, vomiting, purging, delirium, and all the violent symptoms of intoxication. Both the plant and its effects were first described l by Gmelin and Steller, in 1747, as a Siberian remedy for rheumatism; but it was not much noticed till after 1779, when Kcelpin strongly recommended it in that disease, and also in gout and lues venerea. Besides the effects we have already mentioned, it is said to excite a creeping sensation in the pained parts, which after a few hours subsides, and at the same time the pain is relieved. It has not been much used in this country, but, from the result of some trials of it in

1 Flora Sibirica, iv. 121,

Scotland, it has obtained a place in the Edinburgh Pharmacopoeia.

It is given in the form of decoction, made by boiling 3 iv. of the leaves in f x. of water in a close vessel, over a slow fire, for twelve hours. The dose of the strained liquor is from f j. to f ij. given twice a day, and gradually increased.