"Tougoku-shida" (Dryopteris nipponensis) belongs to the Polypodiaceae (the Polypody family). It is an evergreen fern that is native to Honshu, Shikoku and Kyushu. This fern grows in flatland to montane forests and can reach 50-100 cm in height. The leaves are bipinnate compound with short caudal tips. The pinnae are ovate-lanceolate or oblong-lanceolate, thin papery leathery, and dissected pinnately. The petioles are long, hard, and covered thickly with black-brown scales. The sori are small and arranged near rachis. The Japanese name is derived from Mount Tougoku which is in Aichi Prececture of Honshu.