Marrubium
(the old Latin name used by Pliny, probably derived from the name of a town in Italy). ORD. Labiatae. A genus comprising about thirty species of hardy perennial, usually tomentose or woolly herbs, of no horticultural value. Flowers in generally many-flowered axillary whorls. Leaves wrinkled, rarely cordate at the base, usually cut; floral leaves similar, exceeding the flowers. M. vulgare is the common Horehound (which see for culture).