Submerged perennial. Stem thick, up to 3 m long, simple, rarely branching, glabrous. Rhizome rooting. Leaves 20-35 mm long, pinnatisect, segments 20-35, linear and filiform. Spike 10-30 cm long. Bracts 10-25 mm long, pectinate, the lower most sterile. Flowers sessile, in whorls of (4-) 5, in the axils of bracts, the upper male, the lower female with a few bisexual ones in between. Male flower: calyx tube c. 1 mm long, lobes triangular; petals 4, oblong-ovate, 2.5-3 mm long, greenish-yellow. Stamens 8, filaments slender; anthers c. 2 mm long. Female flower: calyx as in the male; petals lacking. Ovary subglobose, c. 2 mm long, 4-locular; style short, stigmas plumose. Fruit a schizocarp. Seeds elongated, 1.5 mm long, smooth.

Fl.Per.: July-August.

Type: Described from Europe, Hb.Linn.1123/2(LINN).

Distribution: Throughout Europe, Asia, N. & S. America, N. Africa.

Grows in thickets in lakes and ponds. Found abundantly in the Kashmir Valley lakes. Collected here in a stream in the Salt Range, Jhelum Dist. at c. 700 m.