Plants not scapose; glabrous, pubescent, hirsute, or pilose. Stems usually erect or ascending, sometimes procumbent, decumbent, or prostrate, unbranched or branched. Leaves usually basal and cauline (basal absent in L. fremontii); petiolate or sessile; basal rosulate or not, petiolate (or petiole undifferentiated from blade), blade margins entire, dentate, denticulate, serrate, crenate, or lobed; cauline petiolate or sessile, blade (base auriculate or not), margins entire, dentate, or pinnately divided. Racemes (usually corymbose), elongated or not in fruit. Fruiting pedicels erect to divaricate, slender or stout. Flowers: sepals (usually deciduous, sometimes persistent), usually ovate or oblong, rarely suborbicular; petals (erect or spreading, sometimes rudimentary or absent), obovate, spatulate, oblong, oblanceolate, orbicular, linear, or filiform, claw absent or differentiated from blade, (apex obtuse, rounded, or emarginate); stamens 2 or 4 and equal in length, lateral or median, or 6 and tetradynamous; filaments not dilated basally; anthers ovate or oblong; (ovary placentation apical); nectar glands (4 or 6), distinct, median glands often present. Fruits schizocarps or silicles, (rarely indehiscent), sessile, didymous, oblong, ovate, obovate, cordate, obcordate, elliptic, orbicular, ovoid, obovoid, or globose, strongly angustiseptate or inflated and terete; valves each with prominent veins or not veined, (keeled or rounded, apex winged or not, thin or strongly thickened and ornamented, enclosing or readily releasing seed), glabrous or pubescent; replum rounded, (visible); septum complete or perforated; style absent, obsolete, or distinct, (included or exserted from apical notch); stigma capitate, usually entire, rarely 2-lobed. Seeds oblong or ovate [obovate], plump or flattened, winged, margined, or not winged; seed coat (smooth, minutely reticulate, or papillate), usually copiously mucilaginous when wetted, rarely not; cotyledons usually incumbent (accumbent in L. virginicum) [diplecolobal].