Plants erect, emergent or floating, 30-120 cm. Stem terete, nearly always branched above. Leaves linear, 15-20 mm broad, triquetrous at the base. Branches bearing globose heads borne in the axils of large, leafy sheathing bracts, proximal end of branches bearing 1-3 female heads, male heads many at the distal end. Male flower with 3 or more connate or free stamens; anthers bibbed, basifixed, 1-1.5 nun long; filaments 3-5 mm long; perianth segments linear-spathulate, thickened, dark brown-black at apex, entire, 2-3 x 1-1.5 mm. Female flowers sessile; perianth segments 3 or more (usually 4), 1.5-3 x 1-1.5 mm, mostly spathulate, sometimes lanceolate-oblong, thickened, dark brown-black at apex, entire; ovary usually unicarpelate; style simple or bifurcate; stigmas 1 or 2, linear. Fruits obpyramidal below and domed-conical above, distinctly angled, usually sessile.

Fl.Per.: February-June.

Type: India, Wallich 4990 (Holotype destroyed in B; Isotype - K).

Distribution: Caucasus and Afghanistan eastwards through north-eastern Pakistan to northern India, Tibet, southern China, Japan, south-east Australia, western north America from California to British Columbia.

Sparganium erectum is a variable and a widely distributed species. Cook & Nicholls (1986) recognized 5 subspecis viz erectum, stolonijerwn, microcarpum, neglectum and oocarpum, on the bases of structure, texture and colour of fruits. Our material agrees with Sparganium erectum subsp. stoloniferum.

Plant is reputed to be useful for abdominal pain, amenorrhoea and chest pain (Duke & Ayensu, Med.Pl.China, 2:614,1985). Its fruits are used as astringent, haemostatic and vulnerary (Chada et al., Wealth India 10: 1, 1976).