734 ORDER 155. CYPERACE^E. 



dric; spikes 3 to 5-flowered, with a Iroad rachis and distinctly Wangled; glumes 

 slightly mucronate ; ach. oblong, 3-angled. Marshes, S. Oar. to Ma. (Elliott 

 Baldwin.) 



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

 margined, about as long as the stem ; umbel some compound, with elongated rays 

 and oblong, loose clusters, their slieatlis 3-bristled; iuvolucels or setaceous; 

 spikelets numerous, linear-subulate, spreading horizontally, 8 10-fiowered, 7 9" 

 long; in vol. 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. 



ft. SPECIOSUS. Umbel compound, the partial umbels with leaf-like involucels. 

 (C. speciosus Vahl.) 



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

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

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

 clusters ; glumes distant, lance-linear, veined ; ach. linear-oblong. N". Car. to Ga. 

 and Tenn. Spikes 6 to 8" long, of a dusky yellow. 



15 C. Schweinitzii Ton*. Culm 8 12' high, triquetrous, rough on tho angles; Ivs. 

 shorter than tho stem, about a line 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-flowered, with a small, setaceous bract at the base of each; scales 

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

 smooth achenia* 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-uncinato 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 the 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; fls. very regularly imbri- 

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

 Ill (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. Nut 

 dull yellow. (C. vegetus Ell. Torr.) 



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

 rather shorter; invol. 6 to 10-leaved, 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 racnis. 

 (C. Baldwinii Torr. Mariscus, Ell.) 



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

 at base; Ivs. radical, channeled, about J" wide; umbel 4 Q-raycd capillary, erect, 

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

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

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

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



21 C. filiculmis Yahl. Culm slender, almost filiform, tuberous at base, 8 12' long, 

 leafy only at base ; Ivs. mostly radical, carinatc ; 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 Fla., W. to III Aug. (C. mariscoides Ell.) 



22 C. Compressus L. Culm naked, 3-angled, 3 to 8' high, tumid at base; 

 umbel sessile or simple and few-rayed, rays spreading; spikes lanceolate, 2-edged, 



