Annual or biennial, procumbent or suberect, glabrous or hairy with simple hairs or minute tubercles. Leaves pinnatisect or deeply dissected. Racemes short, capitate, ebracteate, axillary or terminal, sometimes apparently leaf opposed. Flowers minute, shortly pedicelled. Sepals sub-spreading, ovate, not saccate at the base, often lilac or pinkish. Petals minute, whitish, scarcely exceeding the sepals, or absent. Stamens 6, or only 4 or 2 by abortion; filaments simple; anthers minute, subglobose. Nectar glands minute dot-like, between the stamen bases. Ovary subglobose-bilobed, 2-ovuled; stigma minute, almost sessile. Siliculae short, usually with 2 hemispherical lobes breaking away with 1 seed each; valves thick, reticulately pitted or tuberculated; septum very narrow; radicle incumbent.