Japan Flora: Rhizomes stout, 1-15 cm. in diameter, decumbent; leaves on a long terete petiole 10-25 cm. long, cordate at base, entire, 7-12 cm. long and as wide, nerves slender, many, inconspicuous, curved inward at tip; scapes 15-30 cm. long; spathe 4-6 cm. long, 3-5 cm. wide, rather flat, ending in a mucro to 7 mm. long; spadix 1.5-3 cm. long, narrowly oblong at anthesis, to 5 cm. long, and ellipsoidal in fruit, densely flowered, the peduncle 7-12 mm. long. Shallow water and swampy places around ponds in moors.
Hokkaido, Honshu (n. distr.). Europe, Siberia, n. Asia, and N. America.