Perennial climber. Stems slender, flexuous, more or less puberulent. Leaves 2-­7 (-8) x 2.5 (-7) cm., ovate-cordate with rounded auricles, obtuse and slightly retuse at apex, entire, papillose-hispid on both sides or sometimes glabrous above, green, glaucous beneath; petiole as long as blade, sometimes shorter. Pedicels shorter than flowers, elongating in fruit, hispid-puberulent or subglabrous. Flowers 1.5-3 cm., solitary in axils. Perianth violet, hispid-pubescent or partly glabrous; utricle shorter than pedicel, almost globular; tube strongly incurved; limb as long as or shorter than tube, oblong-lingulate or oblong-triangular, pubescent or glabrous. Ovary more or less hirsute. Capsule 1-2 cm., pyriform to subglobular, densely or sparingly pubescent. Fl. March-May.