508 CYiM-.UACK-i:. (sr.ixn: ivmii.v.) 



♦ * Spikelets compressed, somewhat l-rankid, mostly few and scattered on the com- 

 mon rachis : fieretmials, with creeping tiihcr-bcarini/ rootslocks : Jfowcrs mostly 

 abortive. 



12. C. repens, Ell. I'mlicl mostly simple, erect, 5- C-iMycd. sliortcr tlmn 

 the 3-5-lcavcd involucre; spikelets linear, 8j)reailin'^, 12 - 24-Ho\vere<l, the 

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

 prcssed-kcelcd, thin-margined, spreading at the apex, yellowish brown ; nut ob- 

 long, triquetrous, acute. — Sandy soil near the coa.st, Florida, and northward. 

 July - Sept. — Culms 1°- 1^° high, acute-angled, longer than the erect smooth 

 leaves. Hays 2' -4' long. Spikelets 6" - 8" long. Whole plant yellowish. 



13. C. lutescens, Torr. & Ilook. Umbel simple, large, 5-7-ra3'cd, short- 

 er than the 3- 5-leaved involucre ; spikelets horizontal, flat, linear, 30-40-flow- 

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

 rounded on the back, slightly spreading at maturity ; nut oI)Ovate-oblong ; culms 

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

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

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



14. C. rotundus, L. Umbel simple or compound, 3-8 rayed, mostly 

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

 flat 20- 30-flowcred spikelets; scales oblong, obtuse, appressed, 7-ncrved on the 

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

 slender, longer than the broadly linear crowded spreading 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 ^'-1' 

 long. 



2. SPAiJSiri.oni. Umbel compound : spikelets compressed, ma»i/-J}owered, scattered 

 in loose spikes at the jiliform summit of the rai/s: scales thin, b-nerved, separate : 

 joints of the rachis slightly margined: stamens 2. 



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

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

 ing, nearly orbicular, obtuse or emarginate, short-mucronate, 5-ncrved on the 

 green keel, the thin whitish sides minutely pitted; nut oblong-obovatc, abruptly 

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

 the smooth narrow leaves. — Santee Canal, South Carolina, Ilavenel. Probabl} 

 introduced from Eastern Asia. 



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

 pressed, many flowered, 3-10 in a cluster at the summit oj the general and par. 

 tial rays : scales closely imbricated, 3 - 1-nerced, decurrent on the rachis : sta 

 viens 3. 



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



16. C. articulatus, L Umbel compound, many-rayed, spreading or re- 

 ciin'cd ; involucre of three bract-like pungent leaves; spikelets long (^'-1^' 

 long), linear, spreading, 30 - 40-flowcred ; scales whitish, oblong, obtuse, 7-nerved 



