HEDYSARUM, in botany, a genus of the decandria order, belonging to the diadelphia class
of plants. There are 49 species of this plant, of which the most remarkable are, 1. The movens, or moving plant, a native of the East Indies, where it is called barrum chandalli. The seeds of it were sent to Edinburgh by Mr Kerr, and the plant is now growing in the botanical garden there. It arrives at the height of four feet, and in autumn produces bunches of yellow flowers. The root is annual or biennial. It is a trifolious plant, and the lateral leaves are smaller than those at the end, and all day long they are in constant motion without any external impulse. They move up and down and circularly. This last motion is performed by the twisting of the footstalks; and while the one leaf is rising, its associate is generally descending. The motion downwards is quicker and more irregular than the motion upwards, which is steady and uniform. These motions are observable for the space of 24 hours in the leaves of a branch which is lopped off from the shrub if it is kept in water. If from any obstacle the motion is retarded, upon the removal of that obstacle it is resumed with a greater degree of velocity. This species was unknown to Linnaeus.—2. The coronarium, or common biennial French honeyfuckle, hath large deeply-striking biennial roots; upright, hollow, smooth, very branchy stalks, three or four feet high, garnished with pinnated leaves; and from the places of the leaves proceed long spikes of beautiful red flowers, succeeded by jointed seed-pods.
Culture. The first species being a native of hot climates, requires the common culture of tender exotics; the second is easily raised from seed in any of the common borders, and is very ornamental.