20 
Niagara Falls, N. Y. (Morong); Delaware River, Belvidere, N. J. 
(Britton); Beaver River, Mich. (Hill); Vermilion Lake, Minn. (L. H. 
Bailey); National Park (Clifford Richardson); Utah (M. E. Jones); 
Oregon (Howell). Attributed by Brewer and Watson in Bot. Cal. 
to Montana, Colorado and California. July, August. (Plate 
XXX.) 
7. POTAMOGETON LONCHITES, Tuckerm. Am. Jour. Sci. and Arts, 
2d ser. vi. 226 (1848). 
P. fluitans. Tuckerm. Am. Jour. Sci. and Arts, 2d ser. vii. 348 
(1849), not Roth? 
P. fluitans, Roth, Fl. Germ. i. p. 72 (1788)? 
P. Americanus, Ch. and Sch. Linnea, ii. 226, t. vi. f. 25 (1827)? 
Stem slender, terete, much branched, elongated, 3 to 6 feet 
and sometimes more in length. Floating leaves coriaceous, usu- 
ually rather thin, elliptical, pointed at both ends, 2 to 4 inches 
long and 6 to 14 lines wide, 17 to 24 nerved, on petioles 2 to 8 
inches in length. Submerged leaves very thin and pellucid, often 
with an irregular cellular-reticulated space on each side of the 
midrib, 4 to 13 inches long by 2 to 12 lines wide, rather rounded 
at base or tapering gradually into a petiole 1 to 4 inches long. 
The stipules vary much in different plants, usually 3 or 4 inches 
long, but often only 1 or 2 inches long, acuminate, acute or ob- 
tuse, strongly or faintly bicarinate. Peduncles thickening up- 
wards, 2 to 3 inches long. Spikes cylindrical, 1 to 2 inches long, 
densely fruited. Fruit 134 to 2 lines long, by 1 to 1% lines wide, 
obliquely obovate, face nearly straight or rarely slightly angled or 
rounded, back 3-keeled, middle keel prominent, strongly rounded 
or often with a projecting wing just under the curve of the style, 
not impressed on the sides; style short, facial; embryo slightly in- 
curved, the apex pointing slightly inside of the base. 
Var. NOVJEBORACENSIS, n. var. 
With larger and thicker floating leaves, the blades 3 to 5% 
inches long by 134 inches wide, 20 to 24 nerved, abruptly pointed 
or rarely obtuse at the apex and rounded or sloping at the base. 
Peduncles sometimes 4 or 5 inches long and the spikes 3 inches. 
The submerged leaves and fruit like those of the type. This form 
occurs in Lake Erie, Lake Cayuga, Niagara river, Oneida Lake, 
Lake Seneca, the Erie Canal near it, and in stagnant pools empty- 
