Japan Flora: stems gla­brous; leaves sessile, verticillate in 5’s or 6*s, glabrous, pinnately lobed in the upper half, 1-1.5 cm. long, 3-5 mm. wide, gradu­ally narrowed at base; aquatic leaves finely dissected into lin­ear segments; flowers solitary in axils, the pedicels glabrous, deltoid, acute or with an obtuse tip; cap­sules about 3 mm. across, broadly ellipsoidal; seeds broadly ellipsoidal, about 0.3 mm. long, dark brown. Sept.

Hon­shu; rare. Northeastern China, Korea, Formosa, China, India, Malaysia, and Australia.