North American Cyperacete. 27 i 
C compressus, Linn. sp. p. 6S ; WilUl. sp. 1. p. 282, (excl. syd. 
Vron.) ; Vahl, enum. 2. p. 324; Pursh,fl. 1. p. 51; MuU.! gram. p. 
i5 ; Elliott! sk. 1. p. 65; Ram. Sf Schull. syst. 2. p. 182 ; Kunth, syn. 
1. p. 141 ; Spreng. syst. 1. p. 220, (excl. s}ti. Muhl.) ; N. ah Esenh. in 
Wight's Contrib. p. 76; C. A. Meyer, in Mem. Acad. St. Petersb. VL 
ser. 1. u 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. Umbel often sessile, seldom more than 3-rayed; the 
rays 1 — 2 inches long, spreading. Ochrece cuspidate. Involucre aboirt 
3-rayed, twice as long as the umbel. Involucels wanting. Spikelets 
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 ^e scales; the sides rather convex. Scales somewhat coriaceous, 
pale green, striped with yellow, conspicuously acimiinate and almost 
cuspidate, the points projecting so as to give the spikelets a sharply ser- 
iated 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 sandy soils. North Carolina to Florida, and West 
to Missouri. ^V^ilmington, N. C. Mr. Curtis!; near Charles- 
ton, South Carolina, Elliott! ; New Orleans, Dr.Ingalls!, T. 
Driimmond! ; on the Missouri, Niittall! 
Obs. The C. compressus is also a native of Mexico, and in 
the East and West Indies. 
2-5. Cyperus dextatus, 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.! Jl, 1. p. 61 ; Big. ! Bost. ed. 2. p. IS ; Beck! Bat. 
p. 421 ; Crray ! Gram. S^ Cyp. part 1. no. 71. 
C. par^'iflorus, Muhl. ! gram.]). 19, (not of Fahl.) 
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. 
Leaves rather rigid, shorter than the culm, strongly keeled. Rays of the 
Vol. m. 35 
