Description from Flora of China
Herbs biennial, or perennial. Trichomes unicellular, simple and/or forked, these often mixed with glandular ones with a unicellular gland on a few-celled, uniseriate stalk. Stems erect, often simple. Basal leaves petiolate, usually rosulate, entire, dentate, or pinnately divided. Cauline leaves petiolate or sessile, similar to basal, sometimes auriculate or amplexicaul at base. Racemes bracteate or ebracteate, elongated in fruit. Fruiting pedicels slender or thickened, divaricate or reflexed. Sepals oblong or linear, erect, base of lateral pair strongly saccate. Petals white, lavender, purple, yellow, orange, brownish, or green, much longer than sepals; blade obovate or oblong, apex rounded or obtuse; claw strongly differentiated. Stamens 6, strongly tetradynamous; anthers oblong or linear, obtuse at apex. Nectar glands 2, lateral, ringlike or lunar; median glands absent. Ovules 4-40 per ovary. Fruit tardily dehiscent siliques, linear, terete, 4-angled, or slightly latiseptate, sessile; valves with a prominent midvein, torulose; replum rounded; septum complete, membranous; style obsolete or short; stigma conical, 2-lobed, lobes prominent, connivent or free, decurrent. Seeds uniseriate, wingless, oblong, plump; seed coat reticulate, not mucilaginous when wetted; cotyledons incumbent.
About 25 species: primarily C and SW Asia and SE Europe; two species (one introduced) in China.