Annual, 10-30 cm long herb, spreading or ascending, branched mostly from the base, usually clothed with short, branched and long, simple hairs, often ciliate on stem and fruits, rarely almost glabrous, variable. Basal leaves rosulate, linear-oblong or narrowly elliptic, shortly stalked to sessile, pinnatifid to dentate, 10-20 mm long, 4-15 mm broad; cauline leaves many, similar but becoming smaller above, sessile. Racemes (10-) 20-30 (-40) -flowered, ebracteate or sometimes with a few bracts below, up to 15 cm long in fruit. Flowers 2-3 mm across, white, sub-sessile; pedicels up to 1.5 mm long in fruit and thickened. Sepals 1.5-2 mm long. Petals (2-) 3-4 mm long, 1-1.5 mm broad. Stamens c. 1.5: 2.5 mm long; anthers c. 0.5 mm long. Siliquae linear-subcylindrical, 15-30 (-40) mm long, 1 (-1.2) mm broad, torulose, often reflexed above, spreading, usually hispid or scabrous with short, branched hairs mostly, rarely almost glabrous; stigma sessile, broad, obscurely retuse; septum somewhat rigid; seeds 15-30 in each locule, c. 1 mm long, ovoid.