520 CYPERACE^. (sedge FAMILY.) 



smooth, orbicular, 2-clcft, mucronatc ; antliers obtuse ; style 2-cleft ; nut round- 

 obovatc, plano-convex, as long as the 6 hispid bristles. — Brackish marshes, West 

 Florida, and northward. June - Sept. — Culms 2° - 4° high. Leaves 2' - 4' long. 

 Spikes 2" long. 



^- M- Spikes umhelled. 



5. S. lacustris, L. Culm tall (.3°-8° liigh), terete, leafless, or the radical 

 shoiths lcafy-]>ointcd ; involucre 1 -leaved, pungent, sliortcr than the decompound 

 umbel ; spikes ovate or oblong, mostly clustered ; scales ovate, cmarginatc, rough- 

 awned, ciliate on the margins, pubescent on the back and green keel ; style 2-clcft ; 

 nut obovate, pointed, plano-convex, shorter than the 3-6 strongly hispid bristles. 

 (S. validus, Vahl.) — Varies, with the broader keeled and fimbriate bristles rather 

 shorter than the round-obovatc nut. — Fresh or brackish marshes and ponds, 

 Florida, and )iorthw:ud. July -Sept. 



G. S. leptolepis. Culms3-anglcd,leafy attliebasc (2°-3° liigh); leaves 

 long, shaqjly keeled, triangular-compressed near the obtuse curved apex, the 

 immersed ones flat and pellucid; involucre slender (7' long), leaf-like, with 

 shorter ones at the divisions of the compound umliel ; spikes single, oblong or 

 cylindrical, many -flowered, acute ; scales light brown, lanccolatc-oblong, acute, 

 smooth, membranaceous, mucronate, and, like the three obtuse antliers, finely 

 spotted ; style 3-partcd ; nut whitish, 3-anglcd, oblong-obovate, long-jjointcd, 

 shorter than the 5 slender and minutely denticulate bristles. (S. niaritimus, var. 

 cylindricus. Ton:?) — Lakes and ponds, Middle Florida, and westward. Dr. 

 Hale. September. 



§ 2. Culms jointed, leaf if throughout: umbel terminal: involucre 2 -several-leaved, 



spreading. 



* Bristles hispid dowmvard. 



7. S. maritimus, L. Culm sharply 3-angled, rough above ; leaves longer 

 than the culm, keekd ; umbel simple, 1 -3-raycd, bearing single or 2 - 3 spikes 

 in a cluster, or the spikes all clustered and sessile ; involucre 2 - 4-leaved, much 

 longer than the umbel ; spikes large, ovate or oblong-ovate, dull brown ; scales 

 thin, ovate, pubescent, tipped. with a spreading awn ; nut round-obovate, plano- 

 convex or lenticular, smooth and shining, twice the Icngtli of the 4 weak bristles. 

 — Saline marshes, Florida, and northward. Aug. and Sept. — Culms 2° - 3° 

 high. Spikes 6"- 10" long, 4" in diameter. 



S. S. polyphyllus, Vahl. Culm obtuse-angled, smooth ; leaves long, 

 rough on the margins ; umbel decompound, spreading ; spikes small, 3 - 8 in a 

 cluster, ovate, yellowish-brown ; scales ovate, mucronate, keeled ; bristles 6, 

 slender, hispid near the summit, mostly tortuous, 2-3 times as long as the pale 

 rompres8ed-3-angltd pointed nut. (S. cxaltatus, Pursh.) — Shady swamps, 

 Xorth Carolina, and northward. July. — Culm 2® - 5° high. Spikes l"long. 



9. S. divaricatus, Ell. Culm round-angled, many-jointed; leaves flat, 

 broadly linear; iiiiibcl large, widely spreading or drooping, decompound, longer 

 than tlic 3-Icave(l involucre; spikes all single, oblong-Iincar, scattered; scales 

 ovate, obtuse, H-nervcd. brown on tlie sides ; bristles liair-Iikc, rather ronghcned 

 tlmn hispid, crisped at tho summit, longer than the obovato pointed equal-sidcd 



