ACORUS, a Medicinal Plant, of the Rush or Flag Kind;frequently confounded by the Ancients, and also by the modernApothecaries, with the Calamus Odoratus. See CALAMUS.There are two Species of Acorus; the Verus, or true, andthe false—They are distinguished by this, that from themiddle of some of the Leaves of the former, there arises alongish Cluster of an Infinity of little Flowers, the Thicknessof the little Finger, and resembling Macropiper, orLong Pepper.—The false Acorus is the common Swordgrass.It is only the Root of the Acorus that is used in Physic;and it is this we usually call Acorus—The true is broughtfrom Lithuania and Tartary: It is knotty, reddish without,and white within; as thick as the little Finger, andhalf a Foot long.It is spicy and bitterish; and used in Cephalic and StomachicCompositions.—It is also an Ingredient in the TheriacaAndromachi.Some rank Galangals as a Species of Acorus. See GALANGALS.

ACORUS