Potamogeton pulcher Tuck.

Potamogeton pulcher Tuckerm. Am. Jour. Sci
45: 38. 1843.
Potamogeton lucens fiuitans Robb. in A. Gray, Man. ed. 2. 435. 1856.
Stem simple, rarely branched; floating leaves petioled; blades coriaceous, ovate or orbicular-ovate, acute or obtuse at the apex and cordate or subcordate at the base, 4-10 cm. long, 3-7 cm. wide ; petioles as thick as the stem, 5-10 cm. long, rarely longer ; submerged leaves petiolate ; blades pellucid or semi-coriaceous, the upper lanceolate and the lower spatulate-ovate and sometimes narrowed into a winged petiole, 7-20 cm. long, much narrower than the floating leaf-blades ; stipules 2-keeled, acuminate or obtuse, 2.5-5 cm. long; spikes cylindric, 2.3-4 cm. long, densely flowered, but the fruit rarely maturing ; peduncles as thick as or a little thicker than the stem ; nutlets smooth, 3-keeled, the middle keel more prominent than the lateral ones ; style at least 2 mm. long ; embryo a complete spiral, the curved apex pointing inside the base.
Type locality : Medford, Massachusetts. %
Distribution : Massachusetts to British Columbia, south to Georgia and Arkansas.