Leguminosae
A very large order of trees, shrubs, and annual or perennial herbs, distributed all over the globe. The order is divided into three large sub-orders, some of the principal characters of which are mentioned below. The first of these sub-orders, Papilionaceoe, has a calyx of five sepals, which are more or less united; corolla perigynous, of five irregular petals (very rarely fewer), more or less distinctly papilionaceous, i.e., with the upper petal (the vexillum or standard) larger than the others, and inclosing them in the bud; the two lateral ones (the alae, or wings) exterior to the two lower petals, which last are commonly more or less coherent by their anterior edges, forming a body named the carina, or keel, which usually incloses the stamens and pistil. Stamens ten, rarely five, monadelphous, diadelphous (mostly with nine united into one set, and the tenth, or upper one, separate); or occasionally distinct. Ovary one-celled, sometimes two-celled by an intrusion of one of the sutures, or transversely two to many-celled by cross division into joints. Flowers perfect, solitary and axillary, or in spikes, racemes, or panicles. Leaves simple, or rarely compound, alternate; leaflets almost always quite entire. All the British representatives of the order Leguminosoe belong to the sub-order Papilionaceae, and among illustrative exotic genera are: Cladrastis, Desmodium, Phaseolus, Robinia, Wistaria, &c. Caesalpinieae have the corolla imperfectly or not at all papilionaceous, sometimes nearly regular, the upper or odd petal inside and inclosed by the others. Stamens ten, or fewer, commonly distinct. Illustrative genera are: Coesalpinia, Cercis, Gleditschia, Gymnocladus, &c.
Mimosae have regular flowers, with corolla valvate in aestivation and exserted; stamens often very numerous. Illustrative genera are: Acacia, Albizzia, Mimosa, &c.