Family, Water Milfoil. Calyx, tubular, 3-sided, its border 3-divided. Petals, none. Stamens and stigmas, 3. A nut-like fruit with 3 seeds in as many cells, is borne. Flowers, small, inconspicuous, 1 to 4, sessile, in the axils. Leaves lance-shaped, alternate, sharply toothed; the lower, often under water, cut into comb-like divisions. Stems, low and creeping, 8 to 20 inches high.
Growing in shallow water or in the mud along its banks throughout the Atlantic coast and westward.