Family, Primrose. Color, white or whitish. Calyx, of 5 long, narrow divisions. Corolla, with short tube, spreading, with a 5-parted border. Stamens, 5. Capsule, 5-valved, with many seeds. Leaves, crowded at the base of the cluster of flower-stalks, very much cut into thread-like segments. Flowers, whorled at the swollen joints of stems floating or rooting in mud. Stems, often 2 feet long. May to August.

An aquatic, found in pools and shallow ponds, Massachusetts to Florida. This is a curious-looking plant, owing to the thick, hollow peduncles which spring in a cluster from the submerged stem, coming out of the water and bearing at the joints and on their tips whorls of many small flowers. The lowest joint may be 2 inches long and 1 inch thick. They decrease in size toward the top. The leaves under water look like fine ferns.