Valerian, the popular name chiefly of members of the genera Valeriana and Centranthus, belonging to the gamopetalous and epigynous order Valerianaceae. They have perennial rizomes, which in the British V. officinalis and others have a warm aromatic taste and a fetid odour, which has an intoxicating attraction for cats. The smell is apparently due to valerianic acid. The leaves are opposite, and the flowers small, white or red, and massed together. The calyx forms a feathery pappus in the fruit stage, and the corolla is saccate in Valeriana, spurred in Centranthus. There are three stamens in the former and one in the latter, whilst, of three carpels, two are generally suppressed, the fruit being a one-seeded cypsela and the seed exalbuminous. V. officinalis is cultivated near Chesterfield in Derbyshire, in Holland, and in the North-Eastern United States. The roots of an orchid (Cypripedium pubescens) are imported under the name of American Valerian.