jl^orth American Cyjjeracede. 271 



C-. compressus, Linn. sp. p. CS ; WiUd. sp. 1. p. 282, (excl. syn. 

 Gron.) ; Void, enum. 2. p. 324; Pursh, Jl. 1. p. 51; Muhl.! gram. p-. 

 15 ; Elliott! sk. 1. p. 65; RcEin. Sf Schult. syst. 2. p. 182 ; Kunth, syn. 

 1. p. 141 ; Spreng. syst. 1. p. 220, (excl. syn. Muhl.) ; N. ah Esenh. in 

 "WighVs Contrib. p. 76; C. A. Meyer, in Mem. Acad. St. Petersb. VI. 

 sir. 1. t. 3. 



Root fibrous, descending. Culm 3 — 8 inches high, somewhat tumid 

 at the base, triangular, the sides a little convex. Leaves narrow, carinate, 

 pale green. Umhel often sessile, seldom more than 3-rayed ; thti 

 rays 1 — 2 inches long, spreading. Ochres cuspidate. Involucre about 

 3-rayed, twice as long as the umbel. Involucels wanting. SpUcelets 

 3 — 5 on each ray, in the sessile umbels about 12, from half an inch to 

 nearly an inch in length, remarkably ancipital owing to the acute keel 

 of the scales ; the sides rather convex. Sccdes somewhat coriaceous, 

 pale green, striped with yellow, conspicuously acuminate and almost 

 cuspidate, the points projecting so as to give the spikelets a sharply ser- 

 rated appearance. Interior scales membranaceous, distinct. Stamens 

 3. Style 3-cleft halfway down. Nut very short for its breadth, obtuse, 

 equally 3-sided, when old smooth and shining. 



Hab. Dry saiidy soils. North Carolina to Florida, and West 

 to Missouri. Wilmington, N. C. Mr. Curtis! ; near Charles- 

 ton, South Carolina, Elliott! ; New Orleans, Dr. IngaUs!, T. 

 Drummond! ; on the Missouri, Nuttall! 



Obs. The C. co7np-cssus is also a native of Mexico, and in 

 the East and West Indies. 



25. Cyperus dentatus, Torrey. 

 Umbel compound, with 4 — 7 somewhat erect rays ; spikelets 

 3 — 5 on each partial ray, clustered, ovate-oblong, ancipital^ 

 much compressed, many (6 — 30)-flowered ; rachis naked ; scales 

 very acute, carinate, membranaceous, nerved ; nut obovate,. 

 triquetrous ; rhizoma creeping, bearing tubers. 



C. dentatus, Torr.! % 1. p. 61 ; Big. ! Bost. ed. 2. p. IS ; Beck! Bot. 

 p. 421 ; Gray ! Gram. S>f Cyp. part 1. no. 71. 



C. parviflorus, Muhl. ! gram.\). 19, (not of Vcdil.) 



C. micranthus, Schull. mant. 2. p. 121. 



Rhizoma creeping extensively ; its branches often bearing small tubers 

 at their extremity. Culm about a foot high ; the angles somewhat obtuse, 

 ieareso-ather rigid, shorter than the culm, strongly keeled. Rays of the 



Vol. III. 35 



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