14 TRIANDRIA.— MONOGYXIA. 



alternate ; glumes lanceolate, nervose ; umbel sim 



pie, or compound ; involucrum about 6-leaved. 



pubescent on the margin ; root globose. 

 HAB. Wet grounds. Aug.— Sept. % . 1 — 2 ft. high: 



umb. ochreate; spik. 10-12 fi. yellowish. 

 3. C. tenuis: spikes lanceolate, acute, 10-1 7-flowered ; 



umbel simple ; involucrum 3-4-leaved, longer than 



the rays ; root tuberous. 

 HAB. Culm a span high, slender; spik. yellow ; glum. 



nervose. 

 9. C. phymatodes : umbel simple or decompound ; invo 



lucrum 3-9-leaved ; 3 of the leaves very long . 



peduncles compressed ; spikelets distichous, linear, 



the lower one branched, about 15-flowered; sidet 



rather convex ; glumes oblong, obtuse ; radicles 



tuberous at the extremity. 

 HAB. Wet sand} r places. Aug. U . Root creeping ; 



leav. mostly rad. spreading, carinate ; umb. ochreate. 

 )0. C. compressus : spikes digitate, somewhat by fours ; 



lanceolate ; glumes mucronate, broad, membrana- 

 ceous. 

 HAB. Low meadows. U • Culm 3-8 in. high,ob- 



(us. triang. ; spik. subsessile, 1 6-27 fi. 

 iJ. 0. virens : culm acutely triangular ; umbels decom 



pound ; spikelets ovate-lanceolate, in compact 



heads ; involucrum very long. 

 HAB. Wet meadows and woods. %. 1 — 2 ft. high : 



spik. 16-fi., laterally compressed ; glum, acute. 

 12. C. mariscoides : umbel simple, or with 1 — 2 rays i 



spikelets collected into globose heads, linear,. 7 — 



8-flowered ; glumes loose, obtuse. 

 HAB. In dry situations.. July — Sept. If. Root 



tub. ; culm 8 — 1 2 in. long ; head sometimes solitary , 



spik. atfirst terete. 

 3 C. odoraius : spikelets corymbed, subulate, remote, 



distichous ; glumes somewhat distant ; smaller 



umbels spreading widely, about the length of then 



involucels. 

 HAB. Banks of rivers. -f-« 

 1 1, C. flavicomis: culm triquetrous ; umbel compound 



spikes linear-lanceolate, 7-flowered ; glumes o v : 



tuse ; involucrum very long, reflexed. 



