A climber, glabrous in all its parts. Stem slender, sulcate; internodes about as long as the leaves. Leaves cordate, acute, 5–7-nerved from the base, 4 in. long, 3 in. broad, thinly membranous, exstipulate, basal sinus rounded; petiole 6–9 lin. long, slender. Flowers solitary, axillary; peduncles 2 in. long. Perianth purplish inside with a bright yellow throat, sulphur-yellow outside (Johnson); utricle gibbous on one side, 6 lin. long; tube funnel-shaped, slender below, 4 lin. long; limb cordate, acute, 1 3/4 in. long, 1 1/3 in. wide, basal auricles rounded. Column stalked; anthers 6, nearly 2/3 the length of the column. Style-arms 6, broadly lanceolate, obtuse, incurved, channelled on the outer side. Fruit obovoid-fusiform, 2 1/2 in. long, 9 lin. wide, 6-ribbed. Seed cordate, 2 lin. long, smooth on the inner concave side, muricate on the convex outer, thickened at the margin; raphe not prominent.
