Spec. Plant Willd. iii. 47.

Cl. 14. Ord. 1. Didynamia Gymnospermia. Nat. Ord. Labiatae.

G. 1096. Corolla, lower lip three-parted, with a small intermediate subcrenate segment. Stamens straight, distant.

Species 1. H. officinalis. Common Hyssop. Med. Bot. 3d edit. 318. 113.

Officinal. Hyssopi officinalis herba, Edin. The herbaceous part and leaves of Hyssop.

Syn. Hyssope (F.), Isop (G.), Yzoop (Dutch), Isop (Dan. & Swed.), Isopo (I.), Hysopo (S.), Hyssopo (Port.), Zufaiy yeabus (Arab.).

This is a perennial plant, a native of Siberia and Austria; cultivated in our gardens1, and flowering from June to September. The root is knobbed, woody, and fibrous: the stalk about two feet in height, obscurely quadrangular, erect, shrubby, and branching. The leaves do not exceed an inch in length, and one third of an inch in breadth, are sessile, of a somewhat glaucous deep green colour, elliptical, entire, punctured, and stand in pairs. The flowers are produced on one side, in long, half-verticillated, terminal spikes, and intermixed with leaves. The calyx is persistent, nearly tubular, divided at the edge into five acute teeth, striated, and of a purplish colour at first, but afterwards green: the corolla is violet-coloured, with a long whitish tube; the upper lip short, round, and notched at the apex; the lower one separated into three segments, the undermost of which is inversely ovate. The filaments are crowned with simple anthers; the style is slender and bifid; and the seeds are four, at the bottom of the calyx.

1 It was first cultivated in Encrland by Gerarde, in 1596. It is not the esof of the Hebrews, nor the of the Greeks. It has been supposed to be the zife or cyfe of the Arabians.-Alston's Mat, Med. ii. 152.

Qualities.-The leaves of hyssop have an agreeable, aromatic odour, and a bitterish, moderately warm taste; qualities that appear to depend on a volatile oil of a yellow colour, which can be obtained separate by distillation with water. It is elevated by alcohol also, but soon exhales, and the spirit loses the odour it had when newly distilled.

Medical properties and uses. - Hyssop is stimulant and tonic. It has been recommended in hysteria; and was formerly applied in catarrhal and other pulmonary affections, with the view of promoting expectoration,; but the stimulant properties of hyssop render its use doubtful in these diseases; and, as a tonic, it scarcely merits the least attention.