ctperacejE. (sedge family.) 511 



spikelcts or a single one. Spikelcts somewhat glaucous, 4" - 6" long, serrated by 

 the projecting points of the Bcales. 



27. C. trachynotus, Torr. Umbel simple, of 3-5 short erect rays; in- 

 volucre elongated, 3-leaved ; spikelets several in a cluster, lanceolate, compressed, 

 12-20-flowered; scales whitish, ovate, acuminate, loosely imbricated in fruit, 

 hispid-serrulate on the keel, the broad margins embracing the pear-shaped acutely 

 angled nut; culm flattened on one side, rounded on the other, as long as the 

 slender keeled leaves. — Dry sandy soil, South Florida. May-Nov. — Culms 

 9'- 15' high, straw-color, like the leaves. Spikelets £' long. 



* * Spikelets numerous in compact globular or oblong heads. 

 *- Perennials : culms tumid or tuberous at the base. 



28. C. fuligineus, n. sp. Head solitary, globose, shorter than the 2-leaved 

 involucre; spikes lanceolate, acute, compressed, 8- 12-flowered ; scales (black) 

 ovate, obtuse or emarginate, mucronate; nut oblong-obovate ; culms filiform, 

 obtuse-angled, thrice the length of the narrow rigid leaves. — Key West. No- 

 vember. — Culms £°-l° high. Sheaths of the leaves blackish. Head 5" in 

 diameter. Scales 9-nerved. 



29. C. filiculmis, Vahl. Umbel of 1 - 2 spreading rays or none ; invo- 

 lucre 3 - 4-leaved ; spikelets 15-20, in a dense globose head, linear-lanceolate, 

 6- 10-flowered; joints of the rachis barely margined; scales (greenish) ovate, 

 obtuse or emarginate, short-mucronate, loosely imbricated ; nut obovate ; culms 

 (10'- 15' high), slender, wiry, longer than the linear leaves. (C. mariscoides, EU.) 

 — Dry sandy soil, Florida, and northward. July - Sept. — Heads £' in diameter. 



30 C. Grayii, Torr. Umbel of 4-6 erect rays, shorter than the 3-4- 

 leaved involucre ; spikelets 6 - 9 in a rather loose head, linear or linear-lanceo- 

 late, 5 - 7-flowered ; joints of the rachis winged; scales (brownish) closely im- 

 bricated (spreading in fruit), ovate or oblong, obtuse ; nut obovate; culms (8'- 

 12' high) filiform, wiry, longer than the bristle-shaped leaves. — Dry sandy pine 

 barrens, Florida, and northward. Aug. and Sept. 



31. C. OVUlaris, Torr. Umbel 3-6-rayed, rarely wanting ; heads small, 

 globose or oblong; spikelcts (l|"-2"long) angular, obtuse, 2-4-flowered; 

 scales ovate-oblong, obtuse, mucronate, closely imbricated; nut oblong; culms 

 filiform, smooth ; rather acute-angled, much longer than the rigid filiform leaves. 

 (Mariscns ovularis, Vahl. M. eylindrieus, Ell.) — Wet or dry soil, Florida, and 

 northward. Aug. and Sept. — Culms ^° - 2° high. Heads 2" - 3" in diameter. 



32. C. retrofractUS, Torr. Umbel of about 8 slender (2' -6' long) rays, 

 longer than the involucre ; heads obovate ; spikelets subulate, reflexed, terete ; 

 scales 4-5, the two lower ones ovate and empty, the upper lanceolate, acute ; 

 nut linear-oblong: culm tall (2°-4°), downy and roughish. like the broadly 

 linear leaves. (Mariscus retrofractus, Vahl.) — Barren sandy soil, Florida, and 

 northward. July- Sept. — Leaves much shorter than the culm. 



-•- ■*- Annuals : roots fibrous. 



33. C. Baldwinii, Torr. Umbel 6- 12-rayed, shorter than the involucre; 

 heads globose or oblong ; spikelets linear, somewhat compressed, acute, 6-12- 



