I 



322 North American Cyperacea. 



the base clothed with several sheaths which occasionally bear short 

 leaves. Umbel (or rather cyme) growing from one to three inches below 

 the summit of the culm ; or the inflorescence may be regarded as termi- 

 nal, with a single-leaved straight involucre or bract at its base. Spikes 

 nearly one third of an inch long, mostly ovate, but sometimes oblong, 

 aggregated in threes at the summit of the peduncles or divisions of the 

 umbel. Scales broadly ovate or obovate, obtuse, and frequently emar- 

 ginate, mucronate, distinctly ciliate and clothed with a minute pubes- 

 cence, generally marked with two or more curved wrinkles ; the sides 

 ferruginous and dotted when young ; the keel green. Bristles 4 — 6, very 

 thick, a little longer than the nut, retrorsely hispid. Stamens 3. Nut 

 broadly obovate, dark broAvn, very minutely papillose, strongly convex 

 in front, flat on the back. 



Hab. Lakes, fresh water ponds and swamps, from latitude 

 60° north to the Gulf of Mexico, and from the Atlantic to the 

 Pacific Ocean. 



7. SciRPUs TRiQUETER, Linn. 



Culm triquetrous, nearly leafless, (the base bearing one or 

 two short leaves) ; spikes 1 — 5, aggregated, sessile, ovate- 

 oblong; scales orbicular-ovate, mucronate; bristles slender, 

 shorter than the nut ; style 2-cleft ; nut unequally doubly con- 

 vex, acuminated. 



S. triqueter, Linn. ; Willd. sp. 1. p. 302 ; R. Brown, prodr. 1. p. 223; 

 Ram. SfSchult. syst. 2. p. 141; Smith, Eng.fl. 1. p. 60; Kunth, syn. 1. 

 p. 156 ; Miehx. .' fl. 1. p. 47 ; Muhl. ! gram. p. 33. 



S. Americanus, Pers. syn. 1. p. 68; Pursh, fl. 1. p. 5&', Elliott, sJc. 1. 

 p. 80 ; Big. fl. Bost. ed. 2. p. 21 ; Torr. ! fl. 1. p. 47 ; Beck, hot. p. 425 ; 

 Gray .' Gram. 8f Cyp. 2. p. 135 ; Roem. Sf Schult. syst. 2. p. 129. 



S. pungens, Vahl, enum. 2. p. 255 ; Ram. S^ Schult. syst. 2. p. 128. 



S. mucronatus, Pursh-' fl. 1. p. 55; Elliott, sk. 1. p. 80. 



Culm 3 — 5 feet high, slender, mucronate at the extremity, very acutely 

 triangular, two of the sides concave, the other side flat ; sheaths at the 

 base often bearing one or more leaves several inches in length. Spikes 

 in a dense cluster near the summit, or some distance down the culm. 

 Scales often emarginate, with the midrib produced into a point nearly a 

 line in length ; the sides ferruginous ; margin scarious and somewhat 



