r)38 CYl'KKACE.K. (sKDUE FAMILY.) 



."51. C. compressus, r.. rmliel simple or CDinpouiKl, often sessile, shorter 

 tli.iii till' 4 - (1 Ifiufil involiiere ; .spikeieis spreailiiiy, linear, Hat, 12 -.'JO-liow- 

 ered ; stales ovate, aeiuninato, closely inilniiated, keeled ; nut broadly (d)ovato, 

 aeiite-aiiji^led, Mark and shining ; culms olituseangle<l, longer tiian the palo 

 green leaves. — Cultivated grounds. July-Sept, (l) — Culms 4'- 12' iiigh. 

 Umbel spreading, .sometimes reduced to few spikelets or a single one. Sjjike- 

 lets somewhat glaucous, 4" -6" long, serrated by the jjrojecting points of the 

 scales. 



32. C. viSCOSUS, Ait. I'lMliel siinjile, of 3 - .5 short erect rays ; involucre 

 elongated, Sleaved ; spikelets several in a cluster, lanceolate, compressed, 

 12-20-Howcred ; scales whitish, ovate, acuminate, lu<jsely imbricated in fruit, 

 hispid-serrulate on the keel, the l)road margins embracing the pi'ar-sha|)ed 

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

 as the slender keeled leaves. — Dry sandy soil, South Fhjrida. Jlay - ><ov. 

 — Culms 9'- 15' high, straw-color, like the leaves. Spikelets i' long. 



* * Spihelets numerous in compact globular ohlonrj or cylindrical heads. 



33. C. fuligineus, Cliapm. Head solitary, globose, sliorter than the 

 2-leaved involucre; s])ikes lanceolate, acute, conijjressed, 8 - 12-Howered; scales 

 ( black) ovate, obtuse or emarginate, mucrouate; nut oblong-obovate ; culms 

 filiform, obtuse angled, thrice the length of the narrow rigid leaves. — Key 

 West. Nov. — Culms ^^-1° high. Sheatlis of the leaves blackish. Head 

 5" in diameter. Scales 9-nerved. 



34. C. filiculmis, Vahl. Umbel of 1 -2 s])reading rays or none ; involu- 

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

 6- 10-Howered ; joints of tlie rachis barely margined; scales (greenish) ovate, 

 obtuse or emarginate, sliort-mucronate, loosely imbricate<l ; nut obovate; 

 culms (10'- 15' high), slender, wiry, longer than the linear leaves. — Dry 

 sandy soil. July -Sept. — Heads ^' iu diameter. 



35. C. Martindalei, Britton. Allied to the ju-eceding, but taller (1^°- 

 2° high) ; umbel 2 - 8-rayod, spikelets compressed, acute ; scales closely imbri- 

 cated ; racliis winged. — Dry pine barrens near the coast, West Flc^rida. 



36. C. Gl'ayii, iurr. 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 

 imbricated (s]jreading in fruit), ovate or oblong, o])tuse ; nut obovate; culms 

 (8'- 12' higli) filiform, wiry, longer than the bristle-slinped leaves. — Dry 

 sandy pine barrens, North Carolina (Curtis), and northward. August - 

 Sept. 



37. C. OVUlaris, Torr. Umbel 3 - 0-rayed, rarely wanting ; heads small, 

 globose or oblong; spikelets (H"- 2" long) angular, obtuse, 2-4-flowered ; 

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

 smooth, rather acute-angled, mostly longer than the leaves. — Wet or dry 

 soil, common and varialile. August - Sept. — Culms i° - 2° high. Heads 2"- 

 3" in diameter. 



38. C. retrofractus, Torr. Umbel of about 8 slender (2' -6' long' 

 rays, longer tlian llie involucre; heads obovate; spikelets subulate, reflexed- 



