North American Cyimacea. 309 
2 — 3 lines long, seldom more than 5 or 6-flowored, and sometimes bear- 
ing only one or two flowers. Scales often barren, seldom more than one 
or two of them fructiferous, greenish, wtli a red stripe on each side of 
the midrib. Bristles shorter than the nut, very slender and fragile, 
sometimes entirely wanting. Stamens S. Style 3-cleft about half its 
length. iVi/iwhitisIi, often contracted at the neck, obscurely triangular; 
or rather polygonal from the prominent longitudinal ridges which mark 
its sides, and which are about 15 in number, with very fine transverse 
lines. Tubercle conical-triangular, somewhat free at the base. 
Hab. Borders of ponds; generally partly under water; 
Hudson's Bay to Florida. — June — July. 
Obs. When this plant grows in overflowed situations, its 
culms are quite capillary, and the spikes seldom produce fruit. 
In drier situations the culm is much firmer and wiry. Nees 
ab Esenbeck refers to his Chatocypenis yolymoriyJms, the Scir- 
ims cajnlla^cus of Michaux, and also the Scirims trichodcs, H. 
B. ^'K. ; but Michaux's plant is surely nothing more than a 
slender form of Eleocharis acicularis. 
14. Eleocharis tenuis, Schultes. 
Culm filiform, quadrangular, with the sides concave ; spike 
elliptical, somewhat acute at each end; scales ovate, obtuse; 
bristles 2 — -3 or none ; nut obovate, triangular, with the angles 
prominent, corrugated transversely, and somewhat j>apillose» 
crowned with a minute short triangular tubercle. 
Eleocharis tenuis, Schultes, mant. 2. p. S9. 
Scirpus tenuis, Willd. cnwn. hort. Berol. 1. p. 76 ; Muhl. ! gram. p. 
27; Ham. §f Schult. 2. p. 127; Torr.! fi. 1. p. 44; Beck! hot. p. 425 ; 
Big.fl. Bost. cd. 2. p. 21 ; Sjpreng. syst. 2. p. 205; Darlingt. ! fl. Cest, 
ed. 2. p. 20. 
S. quadrangulatus, Muhl. cat.eA.2 p. 6. (not o{ Michx.) 
Culms scEircely thicker than a horse-hair, 8 — 12 inches long, acutely 
quadrangular, the base clothed with one or two purple sheaths. Spike, 
when young, rather obtuse. Scales dark chestnut-coloured, with a 
whitish scarious margin ; several of the lowest ones larger and empty. 
Bristles 2 — 3, short, slender and fugacious. Style 3-cleft. Nut of a 
