Cruciferae

Herbs, sometimes subshrubs. Leaves spirally arranged, basal ones often in a rosette, exstipulate, petiolate to sessile and amplexicaul, entire to variously divided. Inflorescences terminal or sometimes axillary racemes, in flower mostly condensed and often corymbose, in fruit elongate, usually ebracteate. Flowers bisexual, actinomorphic or slightly zygomorphic, hypogynous, cyclic, tetramerous, heterochlamydous. Sepals 4, free, usually equal, spathulate to clawed, imbricate or contorted. Stamens 6, tetradynamous (rarely 4 or 2), episepalous usually free; anthers usually 2-thecous opening lengthwise. Nectarial glands variously arranged at the filament bases. Ovary superior, sessile or stipitate, of seemingly two united carpels, secondarily divided into two locules by a thin membranous septum (sometimes transversely locular by intrusions from the fruit wall); placentation parietal, ovules usually many, anatropous or campylotropous; stigma bifid or connate. Fruit a bivalved dehiscent siliqua or silicula (see key), sometimes a nutlet, lomentaceous or otherwise constricted. Seeds virtually devoid of endosperm, with cotyledons incumbent, accumbent or variously folded. Distribution. A cosmopolitan family with about 380 genera and more than 3000 species, especially diversified in the Mediterranean and the Irano-Turanian regions as well as in parts of Southern Africa, North America and montane South America. The family is comparatively sparse in the tropics, mainly confined to montane and arid areas.