Small annual herbs, erect, slender, usually simple somewhat roughly hairy with bipartite appressed hairs; stem filiform but rigid. Leaves distant, few; cotyledons often persistent opposite; basal leaves absent; cauline leaves subopposite to alternate, oblong-elliptic, sessile, entire, apex rounded. Racemes few flowered, lax. Flowers small, white (sometimes turning violaceous) ; pedicels short, not thickened in fruit. Sepals erect, not saccate at base. Petals c. twice as long as the sepals, oblong. Stamens dimorphic; filaments not appendaged; anthers of 2 outer stamens dithecous, those of inner 4 usually monothecous, subapiculate. Lateral nectar glands in pairs, oblong-terete; middle glands absent. Ovary linear-oblong, 14-24-ovuled, subcylindrical; stigma short, sub-bilobed, subsessile or sessile. Siliquae linear, subterete-compressed, bilocular, dehiscent, often twisted at the time of dehiscence; valves appressed hairy, 1-veined; septum not veined; seeds 1-seriate, small, oblong, not winged.