Annuals or biennials; not scapose; pubescent, glabrescent, or glabrous, trichomes simple or short-stalked, with forked to substellate or subdendritic (smaller) ones. Stems erect, unbranched basally, branched distally, (basally hirsute with simple trichomes or sparsely pubescent with branched ones). Leaves basal and cauline; petiolate or subsessile; basal (often withered by flowering), rosulate or not, petiolate, blade margins entire or toothed or, rarely, lobed; cauline blade (base auriculate or sagittate), margins entire, dentate to lobed, or denticulate. Racemes (corymbose, several-flowered), considerably elongated in fruit, (rachis straight, rarely strongly flexuous). Fruiting pedicels ascending to divaricate, slender. Flowers: sepals erect to ascending, oblong or ovate; petals usually yellow, rarely white, oblanceolate [spatulate], (longer than sepals), claw and blade somewhat differentiated, (apex obtuse); stamens in 3 pairs of unequal length; filaments not dilated basally; anthers ovate or oblong, (apex obtuse); nectar glands (4), lateral, 1 on each side of lateral stamen. Fruits silicles or, rarely, siliques, dehiscent, shortly stipitate, pyriform, obovoid, or depressed globose [linear], keeled or not, slightly latiseptate; valves each with prominent or obscure midvein, (leathery, smooth, margins of each flattened and connate, apex abruptly caudate and extending 1-2.5 mm onto, and appearing as part of, style), pubescent; replum concealed by connate margins of valves; septum complete; ovules 8-25 per ovary; stigma capitate. Seeds biseriate or, rarely, uniseriate, plump or slightly flattened, not winged or narrowly margined, oblong; seed coat (minutely reticulate), copiously mucilaginous when wetted; cotyledons incumbent or, rarely, accumbent. x = 6, 7, 10, 13.
Sep erect, obtuse, the outer slightly saccate at base; pet yellow, spatulate; filaments linear; anthers ovate; short stamens flanked at base by a pair of semicircular glands; ovules 4-12 per cell; style slender, persistent; stigma capitate; fr obovoid or pyriform, firm-walled, slightly flattened parallel to the septum, somewhat keeled along the sutures, narrowed to the short-stipitate base; annuals or winter-annuals with simple and branched hairs; stems branched above; basal lvs narrowly spatulate, often repand; cauline lvs linear to lanceolate, clasping by a sagittate-auriculate base. 6, Eurasia.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.