"Tsuru-aridooshi" (Mitchella undulata) belongs to the Rubiaceae (the Madder family). It is an evergreen perennial herb that is native to Japan, as well as the southern Korean Peninsula. This herb grows in wettish places of forests, and the stems spread by creeping on the grounds. The leaves are thick, glossy, ovate to oval and opposite with undulate edges. The pairs of white flowers bloom at the terminal branches from June to July. The corolla is usually four-lobate, occasionally five-lobes. The fruits are connate spherical berries, and ripen in red.