28.49
POTAMOGETON oblongus.
Oblong-leaved Pondvjeed.
TEDRANDRIA Tetragynia.
Gen. Char. Flowers sessile Upon a spike which
issues from a sheathing bräctea. Perianth
single, of 4 scales. Anthers sessile, opposite to
the scales of the perianth. Pistils, 2, which
become 4 small nuts. Embryo curved..
Spec. Char. Leaves all stalked ; upper ones coriaceous
floating, oblong-elliptical ; lower linear-
lanceolate. Nuts minute, with their back always
obtuse and rounded. Spike slender, cylindrical,
densely flowered, upon a long terete peduncle.
Potamogeton oblongus. “ Viv. Ann. Got. v. 1 p a r .
2. 162.” Cham, et Schl. in Linnoea, v. 2. 214. t.
6. ƒ. 19. Eries. Nov. FI. Suec. 29. Hooker
Br. Fl. ed. 1. 76. Bertol. FI. Ital. v. 2. 225.
height. FI. .Shrop. 77. t. 4. fig. Bab. Prim. Gl.
Sam . 99.
P. natans, e. Mert. and Koch Deutsch. Fl. v. 1. 839.
S t em s creeping below, solid, nearly cylindrical. Lower
leaves linear-lanceolate, floating ones coriaceous, oblong-
elliptical, somewhat acute, shorter than- their petioles, usually
opposite, many-nerved, and reticulated between the
nerves. Stipules large, membranous, narrowed upwards
but obtuse, many-nerved. Spikes cylindrical, dense, many-
flowered, upon long cylindrical, slender, not thickened,