V. Thapsus: biennial; stem stout, erect, simple or branched, 2-4 feet high, clothed with soft woolly hairs; leaves oblong, pointed, narrowed at the base into two wings running down the stem, the lower ones often stalked; flowers in a dense, woolly terminal spike, sometimes a foot or more long, the corolla large, yellow, three of the filaments covered with yellowish woolly hairs. - High Taper. - Roadsides and waste places. Fl. July, August.
V. nigrum: stem sparingly clothed with woolly hairs, 2-3 feet high, ending in a long, simple or slightly branched raceme; leaves crenate, nearly glabrous above, the lower ones large, cordate-oblong, on long stalks; flowers numerous, small, yellow, with bright purple hairs to the filaments. - Banks and waysides. Fl. July, August.