508 CYPERACE^. (SF.DGE FAillLY.) 



* * Spikelets compressed, somewhat 2-ranked, mostly fetv and scattered on the com- 

 mon rachis : perennials, with creeping tuher-bcaring roolstocks : Jlowers nwstly 

 uborlifc. 



12. C. repens, Ell. Umbel mostly simple, erect, 5- fi-raycd, shorter than 

 the 3 - 5-lc:ived involucre ; spikelets linear, spreading, 1 2 - 24-flo\vered, the 

 lower ones often clustered; scales oblong, obtuse or short mucronate, com- 

 pressed-keeled, thin-margined, spreading at the apex, yellowish brown ; nut ob- 

 long, tri(iuetrous, acute. — Sandy soil near the coast, Florida, and northward. 

 July - Sept. — Culms \°- H° high, acute-angled, longer than the erect sniooih 

 leaves. Rays 2' -4' long. Spikelets 6" - 8" long. Wiiolc plant yellowish. 



13. C. luteseens, Torr. & Ilook. Umbel simple, large, 5- 7-iayed. siiort- 

 er than the 3 - 5-leavcd involucre ; spikelets horizontal, flat, linear, 30 - 40-How- 

 ered, the lowest 2-3 in a cluster; scales light brown, oblong-laneeolatc, acute, 

 rounded on the back, slightly spreading at matm-ity ; nut obovate-oblong ; culms 

 stout (2° - 3" high), acute-angled, shorter than the broadly linear leaves. — Key 

 West. Nov. — Leaves 3" -6" wide, very smooth. Kays 4' -8' long. Spike- 

 lets 1' long, l^^" wide, serrate, the lower ones with a bristly involuccl. 



14. C. rotundus, L. Umbel simple or coni]iound, 3-8rayed, mostly 

 longer than the 3-leaved involucre; spikes composed of 3-9 scattered linear 

 flat 20 - 30-flowered spikelets ; scales oblong, obtuse, apprcssed, 7-nerved on the 

 green keel, the membranaceous sides dark chestnut ; nut obovatc ; culms smooth, 

 slender, longer than the broadly linear crowded sjireading rough leaves. (C. 

 Hydra, Michx.) — Sandy soil, along the coast, Florida to North Carolina. Aug. 

 and Sept. — Culm 9' - 18' high. Rays slender, 2' - 4' long. Spikelets J' - 1' 

 long. 



* 



2. Sparsiflori. Umbel compound : spikelets compressed, many-Jlowered, scattered 



in loose spikes at the filiform summit of the i-ays: scales thin, 5-nerved, separate ; 

 joints of the rachis slightly margined: stamens 2. 



15. C. Iria, L. Umbel 6 - 8-rayed, erect, shorter than the 3 - 4-leaved in- 

 volucre; spikelets erect-spreading, oblong-linear, 12-24-flowered ; scales spread- 

 ing, nearly orbicular, obtuse or cmarginate, short-mucronatc, 5-nerved on tlie 

 green keel, the thin whitish sides minutely pitted; nut oblong-obovatc, al)ruptly 

 pointed; style very short; culms (1° high) slender, acute-angled, longer than 

 the smooth narrow leaves. — Santcc Canal, South Carolina, Raventl. Probably 

 introduced from Eastern Asia. 



3. Palm ATI. Umbel compound or decompound, diffuse: spikelets 2-rankid, com- 

 prcssnl, many-fiowered, 3-10 in a cluster at the summit of the general and par- 

 tial mys : scales closely imbricated, 3 - l-nerved, dccurrent on the rachis : sta- 

 mens 3. 



* Culms terete, knotted, lenficss : involucre very short : nut oblong. 

 If). C. articulatUS, L Umbel compound, many-rayed, spreading or ro- 

 f nrv'cd ; involucre of three bract-like pungent leaves; sjiikelets long (i'-lj' 

 long), linear, spreading, 30 - 40(lowered ; scales whitish, oblong, obtuse, 7-ncrvcd 



