Annuals (sometimes winter); not scapose; pubescent or glabrous. Stems erect or ascending to decumbent, often branched distally. Leaves basal and cauline; petiolate; basal (loosely) rosulate, blade margins pinnatifid to pinnatisect, (lobes) dentate or entire; cauline similar to basal. Racemes (corymbose, several-flowered), considerably elongated in fruit. Fruiting pedicels divaricate-ascending, slender. Flowers: sepals erect, oblong, lateral pair not saccate basally; petals white, oblanceolate, (longer than sepals), claw undifferentiated from blade, (apex obtuse); stamens slightly tetradynamous; filaments not dilated basally; anthers ovate, (apex obtuse); nectar glands lateral (minute), 1 on each side of lateral stamen. Fruits siliques, sessile or subsessile, linear, torulose, straight, latiseptate; valves each with obscure midvein, glabrous; replum rounded; septum complete; ovules (20-)28-44 per ovary; style distinct (conical); stigma capitate. Seeds uniseriate, flattened, narrowly winged, orbicular or suborbicular; seed coat not mucilaginous when wetted; cotyledons accumbent. x = 8.