CYPERACE^. (sedge FAMILY.) 533 



gray. — Wet places, North Caroliua, and northward. August. — Culms 4' - 

 10' high. luvolucre 3-leaved. \ 



3. C. leucolepis, Carey. Spikelets capitate, ovate-lanceolate, flat, acutV 

 5 _7. flowered ; scales ovate, niucrouate, compressed-keeled, 7-nerved, the scari\ 

 ous sides broadly decurreut; style deeply 2-parted; stamens 2-3; nut (imma- 

 ture) oblong, lenticular; culms low (2' -3'), tufted, obtuse-angled, shorter 

 than the smooth keeled leaves. — Damp cultivated grounds, Quincy, Middle 

 Florida. August. — Head 3" -4" in diameter, composed of 3-4 compact 

 clusters; sjjikelets I" long, white. 



* * Spikelets scattered on the common rachis (sjjiked). 



4 C. Nuttallii, Terr. Umbel sessile or of 3 - 6 rays, r-2' long ; spike- 

 lets spreading, linear-lanceolate, acute, light or yellowish brown, 12-20- 

 flowered, the lower ones commonly compound; scales rigid, oblong-ovate, 

 acute or mucrouate, appressed ; stamens 2 ; nut obloug-obovate, very obtuse, 

 grayish and minutely pitted ; culms clustered, 3-angled, 4'- 15' higli ; leaves 

 and involucre narrowly linear. — Salt or brackish soil, Florida, and northward. 

 July - Sept. 



5. C. flavicomus, Michx. Umbel compound, many-rayed ; spikelets 

 crowded, linear, acute, 1 2 - 30-flowered ; scales loosely imbricated, yellowish, 

 round-obovate, emarginate, with broad scarious margins, at length spreading ; 

 rachis broadly margined ; stameus 3 ; nut obovate, black, smooth and shining, 

 barely sliorter than the scale ; culms thick, obtuse-angled, l°-3° high ; leaves 

 broadly linear, as long as the culm. — Low grounds and ditches, Georgia and 

 South Carolina. May- Sept. — luvolucre 3 - .5-leaved. Spikelets 6" - 9" long. 



6. C. polystaehyus, Rottb. Umbel of 4-8 rays, simple or somewhat 

 compound; spikelets crowded, linear, acute, 15 -25-flowered ; scales thin, 

 ovate, acute, closely imbricated ; rachis slightly margined ; stamens 2 ; nut 

 linear-oblong or somewhat club-shaped, .short-pointed, grayish and minutely 

 pitted ; culms filiform, 3-angled, 6'- 12' high ; leaves and elongated involucre 

 very narrow. — Margins of ponds and streams, Florida to North Caroliua. 

 July - Sept. — Rays 1' - 2' long. Spikelets 4" - 7" long. 



§ 2. Cyperus proper. — Style 3-cleJi: nut 3-angled. 

 1. Umbel simple or compound: spikelets spreading, forming loose or compact 

 spikes at the summit of the rays: scales rigid, 7 - ll-nerved : joints of the 

 rachis commonly conspicuously winged: stamens 3. 



* Spikelets approximate or crowded on all sides of the common rachis. 

 ■^- Spikelets compressed. 



7. C. StrigOSUS, L. Umbel large, 4- 8-rayed, simple or compound, much 

 shorter than the involucre ; involucels bristly, shoi'ter than the dense oblong 

 spikes ; spikelets linear, acute, 6- 10-flowered ; scales somewhat scattered on 

 the very slender rachis, oblong-lanceolate, acute, much longer than the linear- 

 oblong acute minutely dotted dull nut ; culms (l°-3° high) tumid at the base, 

 as long as the broadly linear leaves. — Swamps and damp soil. July -Sept, 

 — Rays 4' - 6' long. Spikelets i' - f long. Sheath of the rays bristle-pointed. 



8. C. Stenolepis, Torr. Umbel simple or compound, 6 - 9-rayed, shorter 

 than the 3 - 6-leaved involucre ; sheaths of the rays truncate ; involucels 



