Japan Flora: Woody vine; branches sulcate, with red-brown short appressed hairs while young; stipules ovate, obtuse, deciduous; petioles rather elon­gate; leaves somewhat coriaceous, usually rounded-cordate, bifid, 6-10 cm. long, densely reddish brown pubescent when young; tendrils flat, simple, or usually paired; racemes termi­nal, 8-15 cm. long, many-flowered, densely reddish brown pubescent, the bracts subulate, about 2 mm. long, the pedicels ascending, 15-20 mm. long, obsoletely bracteolate near the middle; calyx 5-lobed, about 6 mm. long; petals rather thick, 6-7 mm. long, pale green inside, densely reddish brown pubes­cent outside, with a claw about as long as the nearly orbicular limb; fertile stamens 3, exserted; ovary villous; legumes coriaceous, oblong or ovate, 5-8 cm. long, 25-30 mm. wide, 1- to 3-seeded, dehiscent, nearly sessile. July. Woods near seashores.

Honshu (Kii Prov.), Shikoku, Kyushu; rare. Ryukyus.