CROTALARIA, RATTLE-WORT: A genus of the decandria order, belonging to the diadelphia class of plants; and in the natural method ranking under the 32d order, Papilionaceæ. The legumen is urgid, inflated, and pedicellated; the filaments are connected with a fissure on the back. There are 11 species, all of them natives of warm climates. They rise from 18 inches to 5 feet in height, and are adorned with flowers of a blue or yellow colour. The most remarkable species is the retusa, with simple oblong wedged leaves. It is a native of the island of Ceylon and some other parts of the East Indies. The flowers are yellow, the pods smooth, cylindrical, inflated, and placed horizontally: they are filled with seeds, which, when dried, and shaken by the slightest wind, emit a rattling noise: and this, by the rude inhabitants of the countries where the plant is native, is attributed to the devil, who is thought to deliver his oracles in this whimsical manner.