Japan Flora: Stems strongly twining, slender, soft-pubescent; cotyle­dons hypogeal; primary leaves lanceolate, long-petiolate; termi­nal leaflet of the ordinary leaves narrowly ovate; bracteoles linear, 1-ribbed, acuminate, about twice as long as the calyx; racemes elongate, long-peduncled; legumes narrow, slighdy in­curved, scarcely inflated over the seeds; seeds cylindric-oblong, the hilum sulcate. 

Introduced from India.