SPARGANIACEAE,  Bur-reed Family

In mud or shallow water; stems erect; leaves alternate, 2-ranked, linear; flowers monosporangiate, in globose sessile or subsessile heads in or above axils of bracts the lower of which are usually leafike; staminate heads above the carpellate, in spikes; staminate flowers of 3 or more stamens mixed with small scales; carpellate flowers with perianth of 3-6 scalelike parts, carpels 2, united, locules 1 or 2, style I, fruit 1-2-seeded.