734 Obder 155.— CTPBRACE^. 



dric; spikes 3 to 5-flowered, with a broad rachis mid distinctly i-angkd; glumes 

 alightly muoronate; aoh. oblong, 3-augled. — Marshes, S. Car. to I'la. (Elliott. 

 Baldwin.) 



13 C. strigosus L. Culm triquetrous, leafy only at base ; Ivs. broad-linear, rough- 

 margined, about as long as tlie stem; unibel some compoimd, with elongated rays 

 and oblong, loose clusters, iheir sheatlis B-brisiled; involuoels or setaceous; 

 spikelets numerous, linear-subulate, spreading horizontally, 8 — 10-flowered, 1 — 9" 

 long; invol. of about 6 leaves, the 2 outer ones very long. — Wet grounds, U. S., 

 frequent. Stem 1 — 2f high, bulbous at base. Umbel yellowish. Sept. 



p. SPEOiosns. Umbel compound, the partial umbels with leaf-like iuvolucels. 

 (C. speciosus Vahl.) 



14 C. Dtenolepis Torr. Culm 2 to 3f high, slender, 3-angled; umbel simple, of 3 

 or 4 elongated rays ; invol. 3 or 4-leaved ; ochrecB (sheaths) truncate, pointless ; 

 spikes crowded, spreading or refiexed, linear, flattened, 5 to 8-flowered, in ovoid 

 clusters ; glumes distant, l^nce-linear, veined ; ach. linear-oblong. — N. Car. to Ga. 

 and Tenn. Spikes G to 8" long, of a dusky yellow. 



15 C. Soh-weinitzii Torr. Culm 8 — 12' high, triquetrous, rough on the angles; Ivs. 

 shorter than the stem, about a lino wide ; umbel simple, erect, 4 — 6-rayed, rays 

 elongated, unequal ; sheaths truncate, entire ; invol. 3 — 5-leaved, longer than the 

 leaves, scabrous on the margin ; spikelets G — 7, alternate, approximate, in cylindric 

 clusters, 6 — 8-(iowered, with a small, setaceous bract at tJie base of each; scales 

 membranaceous on the margin; sta. 3; sty. 3-oleft, scarcely "longer than tho 

 smooth aohenia. — Shore of L. Ontario (Sartwell) of Lake Erie (Sullivant) to Ark. 



16 C. inflexus Muhl. Culm setaceous, leafy at base, 2 — 3' high ; Ivs. equaling 

 the stem ; umbel 2 — 3-rayed, or conglomerate and simple ; invoL of 3 long leaves ; 

 spikelets oblong, 8 — 12-flowered, 10—20 together, densely crowded into the ovoid 

 heads; glumes yellowish, veined, squarrous-uneinate at tip; sta. 1. — Banks of 

 streams. Free States and British Provinces. Aug., Sept. 



17 C. acuminatus Torr. & Hook. Culm 3 to 12' high, slender, obtusely trique- 

 trous; Ivs. erect, radical, as long as tho stem; umbel 1 — 6-rayed; invol. 3 — 4- 

 leaved, very long; rays unequal, each with a globous head of 15 — 40 spikelets; 

 spikelets 3 — ^11", oblong-linear, obtuse, 15 — 25-flowered; lis. very regularly imbri- 

 cated in 2 rows; glumes acute, with the point recurved; sta. 1 ; aob. duU-grayish. 

 — ^111. (Mead.) and westward. 



18 C. virens Mx. Culm 2 to 4f high, stout, 3-angled; Ivs. nearly as long, 

 strongly keeled, rough-edged ; umbel compound, with 5 to 7 very unequal rays ; 

 invol. of 4 or more leaves, very long, involucels leafy ; spikes ovate, in dense, 

 globular heads, flattened, 10 to 20-flowered; glumes acute, greenish; stam. 1; 

 ach. 3-angled, acute at each end. — Swamps, S. States. Spikes 3 to 5'' long. Kut 

 duU yellow. (0. vegetus Ell. Torr.) 



19 C. eohinatus. Culm 10' to 2f high, 3-angled, bulbous at base; Ivs. numerous, 

 rather shorter; invol. 6 to 10-leavcd, long; umbel simple, G to 10-rayed; spikes 

 short, teretish, acute, 3 to 6-flowered, in dense, globular heads ; glumes striate, 

 tawny, appressed; stam. 3; ach. obovate. — Dry fields, S. States. Root with 

 numerous fibres. Plant very leafy. Spikes 2 to 5'' long, with a broad rachis. 

 (C. Baldwinii Torr. Marisous, BU.) 



20 C. Grayii Torr. Culm 8 — 12' high, filiform, obtusely triangular, erect, tuberous 

 at base ; Ivs. radical, channeled, about J" wide ; umbel 4 — G-rayed capillary, erect, 

 spreading; sheaths truncate; hds. loose, of 6 — 8 spikelets; spikelets linear, com- 

 pressed, 8— 7-flowered; scales ovate, veined, obtuse, imbricated, interior ones 

 lanceolate; sta. 3; sty. 3-cleft; ach. obovate-triquetrous, f tho length of the scale, 

 gray, dotted.— Sandy fields, Mass. to N. J. Sept. 



21 C. filiciilmia VahL Culm slender, almost filiform, tuberous at base, 8 — 12' long, 

 leafy only at base ; Ivs. mostly radical, carinato ; umbel simple and sessile, or with 

 1 or 2 rays; spikes linear-lanceolate, 3 — 8-flowered, flattened when old, collected 

 into globous heads ; glumes remote, loose, ovate, yellowish. — ^Dry, rocky hills, N. 

 Eng. to Pla., W. to IlL Aug. (C. mariscoides Ell.) 



22 C. oompr^ssiis L. Culm naked, 3-'angk-d, 3 to 8' high, tumid at baso; 

 umbel sessUe or simple and few-rayed, raya spreading; spikes lanceolate, 2-odgcd, 



