510 CYTERACEjE. (sedge family.) 



lanceolate, incurved, spreading at the apex ; nut minute, linear-lanceolate, slen- 

 der-pointed ; culms slender (2° -3° high), obtuse-angled or nearly terete ; leaves 

 narrow, rigid, rough on the margins near the summit. — Low pine barrens and 

 margins of ponds, Florida to North Carolina. Sept. 1J. — Culms tumid at the 

 base. Leaves of the involucre horizontal. Heads light brown. 



22. C. Drummondii, Torr. Umbel compound, of 4-6 primary rays, 

 and as many smaller ones, shorter than the 4-lcaved involucre; spikclcts (10 -20 

 in a cluster) oblong or oblong-linear, 40- 50-flowered; scales yellowish, ovate, 

 straight, free at the apex; nut oblong, pointed, abruptly contracted at the base, 

 minutely wrinkled; culms (6'- 15' high) obtuse-angled, very rough, longer than 

 the narrow leaves. — Sandy swamps, Middle Florida, and westward. Septem- 

 ber, (j) 



* * Umbel simple or sessile: spikelets lanceolate or linear, compressed: scales 8-10- 

 nerved, tapering into a long spreading or recurved point : nut obovate-oblong : law 

 tufted annuals. 



23. C. inflexus, Muhl. Umbel of 1 -2 short rays or sessile, much shorter 

 than the 2 — 3-leaved involucre; spikelets very numerous in the clusters (green), 

 oblong-linear (2" long), 10-20-flowered; scales thin, oblong, 8-nerved, gradu- 

 ally pointed; culms weak, acute-angled (2' -6' high), as long as the smooth 

 narrowly linear leaves. — Low sandy places, Apalachicola, Florida, (apparently 

 introduced,) to North Carolina, and northward. July-Sept. — Sheaths of the 

 leaves green. 



24. C. COnfertuS, Swartz. Umbel of 1-2 short rays or sessile, shorter 

 than the 2-leaved involucre; spikelets 8-20 in a cluster, lanceolate, 12-20-flow- 

 ered, reddish brown (3" long) ; scales rigid, oblong, 10-nerved, abruptly pointed ; 

 culms acute-angled (l'-4'high), as long as the linear smooth leaves; sheaths 

 dark brown. — South Florida. November. Spikelets less crowded than in the 

 preceding. 



5. Capitati. Umbel simple or sessile: spikelets inserted on all sides of the common 

 rachis, forming clusters or heads: joints of the rachis mostly winged: scales rigid, 

 5-11 -nerved : stamens 3. 



* Spikelets few in loose clusters. 



25. C. filiformis, Swartz. Clusters sessile ; spikelets 6 - 1 2, erect, terete, 

 Bubnlate, 6-12-flowered; scales scattered, appresscd, oblong, mucronate, finely 

 tterved; rachis very slender, flexuous ; nut oblong, acute; culms tufted, filiform, 

 acute-angled, longer than the bristle-like leaves; involucre 2-leaved, the lower 

 one elongated and erect. — Key West. November 1J. — Culms 4' - lo' high, 

 tumid at the base. Spikelets 4" -6" long. 



2<>. C. compressus, L. QTmbel simple or compound, often sessile, shorter 



than the 4-6-leaved involucre; Bpikelets spreading, linear, flat, 12-80-flowered; 



Bcal< - ovate, acuminate, closely imbricated, keeled , nut broadly obovate, acute* 



angled, black and Bbining; culms obtuse-angled, longei than the pale green 



— Cultivated grounds, Florida to North Carolina, and westward. July- 



Sept. (l; — Culms 4'- 12' high. Umbel spreading, sometimes reduced to few 



