218 TRIANDRU MONOGYNIA. ScirpUS, 



Involucre two-leaved, unequal, erect, shorter than the um- 

 bel. Filaments three, broad, and membranaceous. Sh/le 

 broad, margins fringed. Stigma two-cleft. Seed obcordate, 

 compressed, smooth, light brown. 



17. C. pectinatus. R. 



Culms from three to four feet high, culumnar. Panicle 

 lateral, just below the straight subulate apex of the culm. 

 Scales daggered. Stigma two-cleft. Seed roundish, beset with 

 four pinnate bristles. 



Grows chiefly in marshy places, where the soil is sandy, 



Root fibrous. Culms erect, from three to four feet high, as 

 thick as a quill, naked, round, smooth. Leaves no other than 

 a sheath or two round the base of each culm. Umbel lateral, 

 about its own length below the apex of the culm, compound, 

 rarely decompound, bowing. Spikes oblong. Involucre no 

 other than the termination of the culm, which is erect and 

 about as long as the umbel. Scales chaffy, daggered. Stig- 

 ma two-cleft. Nectarial bristles two on each side of the germ 

 they are beautifully pinnate, and permanent. Seed obovate, 

 compressed, smooth, brown, embraced by the nectarial bris- 

 tles. 



18. S. pentagonus. R. 



Culms, from six to nine 'inches high, somewhat five-sided. 

 Umbel terminal, compound; involucre chaffy; flowers mo- 

 nandrous. Seed obovate, triangular. 



A native of pasture ground. 



Root fibrous. Culms erect, from six to nine inches high, 

 naked, somewhat five-sided, slightly striated, otherwise 

 smooth. Leaves no other than a sheath or two. Umbel termi- 

 nal, compound, small, erect. Involucre, a few small chaffy 

 scales, with long tapering points. Stamens single. Stigma 

 three-cleft. Seed somewhat three-sided, white, scabrous. 



