Description from Flora of China
Herbs annual or perennial. Trichomes stellate, mixed with simple ones. Stems erect or ascending, simple or branched. Basal leaves petiolate, not rosulate, simple, entire, dentate, or sinuate. Cauline leaves sessile, not auriculate, often entire. Racemes several flowered, dense, ebracteate. Fruiting pedicels slender, erect or divaricate. Sepals oblong, deciduous, suberect or spreading, pubescent, base of lateral pair not saccate. Petals white or rarely yellow, much longer than sepals; blade obcordate, apex deeply 2-fid; claw short. Stamens 6, tetradynamous; filaments of median pairs flattened basally, unappendaged or laterally 1-toothed; lateral pair with a basal toothlike appendage; anthers oblong, obtuse at apex. Nectar glands 4; median glands absent; lateral glands 1 on each side of lateral stamen. Ovules 4-16 per ovary. Fruit dehiscent silicles, oblong, elliptic, ovate, obovate, or orbicular, latiseptate, sometimes slightly inflated, sessile; valves veinless or with an obscure midvein, stellate hairy or glabrous; replum rounded; septum complete, membranous; style to 4 mm, glabrous or sparsely pubescent; stigma capitate, obscurely 2-lobed. Seeds biseriate, winged, margined, or wingless, suborbicular or lenticular, plump or flattened; seed coat minutely reticulate, not mucilaginous when wetted; cotyledons accumbent.
Five species: Asia, Europe (especially Balkan Peninsula), naturalized in North America; one species in China.