42. Lepidium virginicum Linnaeus, Sp. Pl. 2: 645. 1753.
Annuals; puberulent, (trichomes cylindrical). Stems simple from base, erect, branched distally, (0.6-)1.5-5.5(-7) dm. Basal leaves (withered by anthesis); not rosulate; petiole 0.5-3.5 cm; blade obovate, spatulate, or oblanceolate, (1-)2.5-10(-15) cm × 5-30(-50) mm, margins pinnatifid to lyrate or dentate. Cauline leaves shortly petiolate; blade oblanceolate or linear, 1-6 cm × (1-)3-10 mm, base attenuate to subcuneate, not auriculate, margins serrate or entire. Racemes considerably elongated in fruit; rachis usually puberulent, rarely glabrous, trichomes curved, cylindrical. Fruiting pedicels divaricate-ascending to nearly horizontal, straight or slightly recurved, (slender, terete or flattened), 2.5-4(-6) × 0.15-0.4 mm, puberulent adaxially or, rarely, throughout or glabrous. Flowers: sepals oblong to ovate, (0.5-)0.7-1(-1.1) × 0.4-0.7 mm; petals (rarely rudimentary), white, spatulate to oblanceolate, 1-2 (-2.5) × 0.3-0.8(-1) mm, claw undifferentiated or to 0.8 mm; stamens 2, median; filaments 0.6-1.2 mm; anthers 0.1-0.2 mm. Fruits orbicular or nearly so, 2.5-3.5(-4) mm diam. (widest at middle), apically winged, apical notch 0.2-0.5 mm deep; valves thin, smooth, not veined, glabrous; style 0.1-0.2 mm, included in apical notch. Seeds ovate, 1.3-1.9(-2.1) × 0.7-1(-1.2) mm; (cotyledons accumbent or incumbent).
Subspecies 2 (2 in the flora): North America, Mexico; introduced in South America, Europe, Asia, s Africa, Australia.
