I 

 518 CYPERACEjE. (SEDGE FAMILY.) 



none. Margins of ponds and streams, West Florida. June -Aug. 

 Culms 3' -5' high. Spikes 1"- 2" long, the lower scales deciduous as new 

 flowers are developed. Nut black, smooth and shining. 



- - Culms terete or compressed, more or less spongy. 



19. E. capitata, R. Brown. Rhizoma slender, creeping; culms com- 

 pressed; spikes short, ovate, 1 2 - 1 6-flowered ; scales mcmbranaccous, whitish, 

 oblong, obtuse, deciduous ; nut black and shining, broadly obovate, biconvex, 

 tipped with the short conical tubercle ; bristles 6, as long as the nut. Springy 

 or miry places, Florida, Georgia, and westward. June - Sept. Ij. Culms 

 l'-4' high. Spikes l"-2" long. Scales often brown when young. Nut very 

 small. 



20. E. olivacea, Torr. Culms compressed, furrowed, diffuse; spikes 

 ovate, acutish, many-flowered ; scales ovate, obtuse, thin, purplish on the sides, 

 green on the keel, the margins white ; nut obovate, dull, dark olive ; tubercle 

 distinct, conical-beaked ; bristles 6-8, about half as long as the nut. Wet 

 sandy places, North Carolina, and northward. Aug. and Sept. Culms 2' - 5' 

 long. Spikes 3" long, 20 - 30-flowered. 



21. E. palustris, R- Brown. Rhizoma creeping; culms slender, terete, 

 striate; spikes oblong-lanceolate, mostly acute, many -flowered ; scales oblong, 

 membranaceous, brpwn on the sides, at length whitish, the upper ones acute ; 

 nut dull yellow, obovate, tumid, minutely dotted; tubercle short, triangular- 

 ovate, compressed; bristles 4, slender, commonly as long as the nut. (Scirpus 

 palustris, L.) Marshes and wet places, Florida, and northward. June- Sept. 

 1|. Rhizoma black. Culms 1 - 3 long. Spikes 3" -5" long. 



22. E. Obtusa, Schultes. Culms tufted, terete, thick and spongy ; spikes 

 ovate or oblong, obtuse, many-flowered ; scales thin, oblong, obtuse, commonly 

 brown on the sides, green on the keel, with broad and white margins; style 

 2-3-cleft; nut^ (light brown) obovate, lenticular, smooth and shining, scarcely 

 wider than the short compressed acute tubercle ; bristles 6, rigid, twice the length 

 of the nut. (Scirpus capitatus, Ell.) Muddy margins of ponds and streams, 

 Florida, and northward. Common. June - Sept. Culms 6' - 18'. high. Spikes 

 2" -4" long. 



2. CEUETOCYPERUS. Spikes few-flowered, compressed: scales membranaceous, 

 imbricated in 2 -3 rows : style 3-cleft. Culms capillary. 



23. E. acicularis, R. Br. Culms (2' -12' high) angled; spikes ovate, 

 5 - 6-flowered, acute ; scales oblong, with reddish sides ', nut oblong, white, 

 nearly terete, longitudinally ribbed and pitted, pointed with the conical or de- 

 pressed tubercle ; bristles 3-4, shorter than the nut, sometimes wanting. (Scir- 

 pus trichodes, MM.) Margins of ponds, Florida, and northward. June- 

 Sept. 



24. E. pygmsea, Torr. Culms short (l'-2' high), grooved on one side; 

 spikes ovate, 3 - 6-flowered ; scales whitish, ovate ; nut ovate, pale, prominently 

 3-angled, smooth and shining, narrowed above into the minute tubercle ; bristles 

 6, longer than the nut, sometimes wanting. (Scirpus capillaceus, Ell.) Muddy 



