"Ruiyo-shoma" (Actaea asiatica) belongs to Ranunculaceae (the Buttercup family). It is a perennial herb that is distributed throughout Japan, as well as the Korean Peninsula, China and Ussuri region. This herb grows in forests of deep mountains, and can reach 30-80 cm in height. The leaves are biternate to triternate compound with ovate to long-ovate, coarsely toothed leaflets. The short racemes are borne at the tip of flowering stems, and the small white flowers bloom in May through June. The small spatulate petals and the calyx lobes are caducous (short-lived). The fruits are spherical berries and ripen in black.