Stems slender, climbing, the comparatively straight internodes 5-7 cm. long; cataphylls at the nodes apparently none; LEAVES: petioles 3-6 cm. long, nearly equaling the blade, conspicuously winged on the basal half or nearly to the summit; leaf-blades narrowly cordate-ovate, 6-9 cm. long, 4-6 cm. wide, acuminate into a slender cusp 2-3 mm. wide and about 1 cm. long, often falcate, the basal lobes rounded, separated by a broad shallow sinus; principal lateral veins poorly developed, about 6 on each side.