Japan Flora: Scandent, woody evergreen, the inflorescence, young branches, and underside of leaves pubescent; leaves elliptic to narrowly so, 4-8 cm. long, 2-4.5 cm. wide, obtuse or acute, short-petiolate; flowers white, changing to yellow, 2-25 cm. across; calyx thin, loosely pilose, 5-6 mm. long, the lobes obtuse and spreading; corolla-tube 7-8 mm. long, the narrow part as long as the broadened upper portion or somewhat shorter, the lobes obliquely obtriangular; anthers included within the tube; style short, not exceeding the calyx; follicles 10-15 cm. long. May.

Honshu (centr. and w. distr.), Shikoku, Kyushu. Korea, and China.

Korea Flora: Evergreen climbing plant. Length over 5m. Stems: Branches reddish-brown, pubescent, producing aerial roots that readily attach to other objects. Leaves: Opposite, elliptic, ovate, or oblong, obtuse, base cuneate, 2-4(6)cm × 1.5-2.5(3)cm. Upper surface dark green, glossy; lower surface glabrous or pubescent, margins entire. Petiole 5-6mm long. Flowers: Cymes terminal or axillary, peduncle 5-10mm long. Flowers 2-3cm in diameter, changing from white to yellow; calyx deeply divided into 5 lobes; corolla 7-8mm long, 5-lobed. Stamens 5, attached to corolla tube, anther tips reaching the mouth of corolla tube; style twice as long as calyx. Fruit and Seeds: Follicles, 10-22cm long, paired, parallel or diverging at acute angle.

Flowering Period: Early June to late July
Fruiting Period: Late August to mid-October
Distribution: Southern Honshu, Shikoku, Kyushu (Japan); Jeollanam-do, Jeollabuk-do, Gyeongsangnam-do, Jeju Island (Korea)