Herb 15-60-(200) cm tall; stems usually green, sometimes purplish black on exposed side. Lvs with lamina partly decurrent or attenuate on petiole, 4-17 × 2-12 cm, ovate or triangular-ovate, often lobed (especially larger lower lvs) or sinuate-dentate, glabrous except sometimes for main veins beneath; apex obtuse to acute; upper lvs often sinuate and entire. Pedicels puberulent, usually green, sometimes purplish black. Calyx 1.5-2 cm long at anthesis, broad-ovate, deeply divided, usually green, sometimes purplish black, very strongly accrescent; apex cuspidate. Corolla 3-3.5 × 2.5-4.5 cm diam.; lower tube white, with 5 small or large purplish markings, the upper part blue; lobes blue, shallow and rounded. Filaments hairy, with base surrounded by tuft of long hairs. Fr. 1-2 cm diam. Seed 1.5-2 mm diam., subreniform or ± irregular, brown, with alveolate testa.