Leguminosæ

Leguminosæ (Fabaceæ of Lindley), a great natural order of exogenous plants, containing herbaceous plants, shrubs, and trees, many of the latter of the greatest magnitude. The leaves are alternate, usually compound, and have two stipules at the base of the leaf-stalk, which often soon fall off. The inflorescence is various. The calyx is inferior, five-parted, toothed or cleft, the segments often unequal. The petals are five, or, by abortion, fewer, inserted into the base of the calyx, usually unequal, often Papilionaceous (q.v.). The stamens are few or many, distinct or variously united. The ovary is one-celled, generally of a single carpel; the style simple, the stigma simple. The fruit is a legume, which is simply a pod composed of two valves, as in the pea and the bean. The seeds are generally numerous, rarely solitary, occasionally with an aril, often curved: the cotyledons very large.—There are three sub-orders: (1) Papilionaceæ, with papilionaceous flowers; (2) Cæsalpineæ, with irregular flowers and spreading petals; (3) Minnoseæ, with small regular flowers.—This natural order contains almost 7000 known species, of which about 5000 belong to the sub-order Papilionaceæ; it is therefore, after the great order Compositeæ, the most extensive of all the natural orders of flowering plants. They are spread over all parts of the world, from the equator to the poles, but their number is greatest in tropical and subtropical regions. They are applied to a great variety of purposes, and some of them are of great importance in domestic economy, the arts, medicine, &c. To this order belong the Bean, Pea, Kidney-bean, and all kinds of pulse; Clover, Liquorice, Broom, Laburnum, Lupine, Senna, and many other medicinal plants, Tamarind, Logwood, Indigo, and many others which afford dyes, &c.; the Acacias, Mimosas, &c. Many species are interesting on account of their beauty of form, foliage, or flowers. In the seeds of many is found a nitrogenous substance called Leguminc (q.v.) or Vegetable Casein.