The leaves and tops of Marrubium vulgare.

Chaeacters. - Leaves about one inch (25 millimetres) long, opposite, petiolate, roundish-ovate, obtuse, coarsely crenate, strongly rugose, downy above, white-hairy beneath; branches quadrangular, white tomentose; flowers in dense, axillary, woolly whorls, with a stiffly ten-toothed calx, a whitish bi-labiate corolla, and four included stamens; aromatic and bitter.

Composition. - It contains a volatile oil and a bitter principle, marrubiin.

Dose. - 30-60 gr. (2-4 gm.).

Uses. - It is expectorant, tonic, diaphoretic, and diuretic. In large doses it is laxative. It is employed in laryngeal and bronchial catarrh, and in chronic affections of the lungs attended with cough and copious expectoration.