Order 155.— CYPERACBiE. 739 



5 S. lactistris L. Lake Bullrcsh. CWntsmooth, leafless, filled with a porous 

 pith, 5 to 8/ high, cylindric, tapering above the panicle, and abruptly ending in a 

 short cusp ; panicle cymous near the top ; ped. rough, twice compound; spikelets 

 ovoid, closely imbricate ; scales ovate, mucronate, pubescent ; bracts shorter than 

 the panicle. — The largest species of buUrush, frequenting the iliuddy margins of 

 rivers and ponds, TJ. S. to Arc. Am, July. (S. acutus MuhL) 



6 S. ptingens Vahl. Culm nearly naked, 3-angled, corners acute and two of 

 the sides concave, about 3f high and ending in a sharp point; Ivs. few and short, 

 from the top of the sheath ; spilces lateral, 1 — 5, ovate, crowded and sessile, at 

 various distances below the point ; glumes round-ovate, mucronate ; bristles 6 ; 

 style i-clefi, — Ponds and marshes, fresh and salt, throughout N. America. (S. 

 triqueter Mx.) i 



7 S. Olneyi Gray. Culm triquetrous-winged, leafless, 2 — 7f high ; sheath radical, 

 tipped with a short (1 — 2') leaf; spikes 6 — 12, sessile, aggregated, 2 — 3" long, 

 placed 9 — 12'' below the triangular apex of the stem ; glumes roundish-ovate, 

 mucronate; bristles 6 — 12 ; ach. obovate, plano-convex, gibhcfns at apex. — Salt 

 marshes, Sekonk river, E. J. (Olney), Tom river, N. Y., Kneiskern. Remarkably 

 distinguished by its 3-winged stem. July. 



8 S. Torreyi Olney. Culm 2f high, 3-angled, with concavS sides, rather slender, 

 leafy at the base; Ivs. 2 or 3, If or more long, slender; spikes 2 — 4 (rarely 1), ses- 

 sile, distinct, acute, ovate-cblong ; scales ovate, mucronate, smooth ; sty. Z-cleft ; 

 ach. obovate, acuminate, unequally 3-sided, shorter than the bristles. — Borders of 

 ponds, N. Bng. to Mich. The stem here as m the last, is prolonged above the 

 spikes, in the form of an involuoral leaf Jl., Aug. (S. muoronatus Ph. ? Torr.) 



9 S. maritinms L. Sea BxjLLsnSH. Culm acutely 3-angled, leafy, 2 — Sfhigh; 

 Ivs. broad-linear, rough-edged, carinate, taller than the stem; spikes conglome- 

 rate, 6 — 10, nearly an inch long, corymbous; invol. of about 3 very long leaves; 

 glumes ovato, 3-cleft, the middle segment subulate and reflexed ; style 3-clcft ; 

 bristles 3 — 4, much shorter than the broad-obovate, lenticular, da/rlt brown, polished 

 achenium. — Salt marshes, N. Eng. to Plor. Aug. 



10 S. fluviitilis Gray. Culm triangular-winged, leafy, stout, 3 or 4f high ; Ivs. 

 broadly linear, very long; invol. Iva 5 to 7, tar exceeding the umbel; umbel 

 somewhat compound, spikes separate or conglomerate, large (9 to 12" long), ful- 

 vous ; glumes 3-cleft, bristles 6, whitish, longer than the sharply 3-angled, oblong, 

 hlack aclienium, which is tipped with a whitish beak. — Borders of lakes and rivers, 

 W. N. Y. and W. States. Jl., Aug. (S. maritimus, /3. fluv. Torr.) 



US. atrovirens Muhl. Culm obtusely triangular, leafy, 2f high ; cyme com- 

 pound, proliferous ; invol. of 3 leaf-like bracts longer than the cyme ; spikes ovate, 

 acute, crowded, 10 to 20 in a ghbous heUd ; hds. numerous, 4" diam., dark olive 

 green ; glumes ovate, mucronate ; bristles 4, straight, hispid downviard, as long as 

 the smooth, white achenium. — Common in meadows. Mid. and "W. States. Jn., Jl. 

 Very different from S. sylvaticus L. of Europe. 



12 S. polyphyllus Vahl. Culm obtusely triangular, leafy, 2 — 3f high ; cyme 

 decompound, its principal branches about 5, unequal, with truncate sheaths at 

 base ; spilcelets clustered in heads of 3 — 6 ; glumes obtuse, reddish-brown ; ach. 

 smooth, yellowish-white, twice shorter than the i or 6 smooth tortuous bristles. — 

 Much resembles tho last species. Margins of waters, N. Eng., 111. and S. States. 

 (S. brunneus Muhl.) 



13. S. divaricktus Ell. Culm obtusely triangular, very leafy, 3 to 4f high ; 

 Ivs. flat, broadly linear or lance-linear, 3 to 6" wide, shorter than the culm ; umbel 

 loose, large, decompound, rays filiform, divaricate, recurved ; spikes all separate, 

 pendulous, oblong-ovoid, 2 to 3" long, rust colored, pendulous ; glumes many, 

 acute ; bristles tortuous, rather longer than the achenium which is tawny, elhptic- 

 3-angled, acute at each end. — Wet barrens, S. Car. to La. (Hale). 



14 S. Eriophornm Mx. Culm obtusely triangular, leafy, 3 to 5f high, Ivs. 2f 

 long, rough-edged; invol. 4 or 5-leaved, longer than (he umbel; umbel terminal^ 

 decompound, largo and loose ; spikes mostly pedicillate, 2 to 3" long, ovoi(^ in 

 smaller clusters ; bristles G, capillary, curled, very conspicuous, being 5 or 6 times 

 as long as the white achenium. — A common, stiff, rank, meadow sedge, which 



