CLASS III. ORDER III. jg 



Syn. Rhyncospora alba. Vahl. 



A smooth, grassy plant, with white heads of flowers. Stem 

 half a foot or more in height, three sided, mostly smooth. 

 Leaves mostly belonging to the stem, alternate, sheathing, the 

 sheaths tubular or entire. Flowers in fascicles on footstalks, 

 terminal and axillary, erect. Glumes white, afterward becoming 

 brownish. Seeds surrounded with short hairs. — In low woods 

 and swamps. — Brighton. — July. — Perennial. 



21. CYPERUS. 

 Cyperus inflexus. Muhl. Inflected Cyperus. 



Heads roundish, glomerate ; spikelets linear, about 

 eight flowered ; glumes squarrose at the tip. 

 Syn. Cyperus xincinatus. Pursh. 



Two or three inches high, with soft, crowded, ascending, slen- 

 der spikelets ; the glumes recurved at the tip. — Wet grounds. — 

 August. 



Cyperus flavescens. L. Yellow Cyperus. 



Spikelets linear-lanceolate, crowded, three or four 

 together ; involucre three leaved, longer than the 

 umbel. 



Spikelets from fifteen to twenty flowered, yellowish green. — 

 Wet grounds. — August, September. — Perennial. 



Cyperus castaneus. Chesnut Cyperus. 



Spikelets ovate-lanceolate, involucre three leaved, 

 longer than the umbel. 



Syn. Cyperus flavescens, (?. castaneus. Pursh. 



Smaller than the preceding ; spikelets broader, chesnut color- 

 ed, fifteen to twenty flowered. — Wet grounds. — August. 



Cyperus diandrus. Torrey. Diandros Cyperus. 



Umbel sessile, or one to two rayed, shorter than 

 the involucre; spikelets oblong-lanceolate, about fif- 

 teen jiowered ; stamens two. 



From eight to twelve inches high, the urnbel sometimes re- 



