Herbs, perennial, to 130 cm; rhizomes present; stolons absent; corms present. Leaves emersed, sessile, phyllodial, lenticular, or with petiole triangular, to 53 cm, blade lance-elliptic, 11--18 ´ 1.5--4.5 cm. Inflorescences racemes, of 3--9 whorls, emersed, 2--13.5 ´ 3--6 cm; peduncles to 75 cm; bracts connate more than ¼ total length, lanceolate, 5--8 mm, delicate, not papillose; fruiting pedicels recurved, cylindric, 0.5--2.5 cm. Flowers to 3.5 cm diam.; sepals spreading in staminate, erect in pistillate, enclosing flower or fruiting head; filaments club-shaped, longer than anthers, pubescent; pistillate pedicellate, without ring of sterile stamens. Fruiting heads 0.7--1.2 cm diam.; achenes oblanceoloid, abaxially keeled, 2--3 ´ 1.4--2.1 mm, beaked; faces not tuberculate, wings absent, glands 0--1; beak lateral, erect, 0.2--0.6 mm. Chromosome number unknown.

Flowering summer (Jul--Sep). Ditches, streams, and lake margins; of conservation concern; 10--300 m; Calif.