358 ORDEK 154. CYPERACEJS. 



3 C. microdontns Torr. Calm and Ivs. slender; spk. numerous, crowded, linear 



acute ; glumes acute, close ; stamens 2 ; achenia oblong, grey, dotted. South. 

 ft. IJattxii. Culm and leaves filiform ; spikes fewer, loose in the umbel. S-W. 



4 C. flavesccus L. Culm and leaves 4 10' ; rays 24, short, the linear obtuse 



spikes clustered at the end ; glumes obtuse, straw-yellow ; achenia shining, (f) E. 



5 C. flavicomiiM MX. Culm 1 3f; involucre 3-5-leaved, very long; umbel some 



compound ; spikes numerous, linear, 12-30-flowered, spreading; glumes very obtuse, 



brownish-yellow, 3-veined. white-edged ; achenia obovate, blackish. Va., and South. 



CJ C. artlciiliitus L. Culm 2 6f, the joints internal, leaves or mere sheaths; 



umbel compound, involucre short; spk. subulate; gls. 14 20, scarious. Swamps, S. 



7 C. erythrorhizog Muhl. Culm 2 3f; umbel compound, each ray with several 



sessile clusters; spikes very many, 6", teretish; glumes 1530, yellow-brown ; inner 

 scales very narrow ; achenia 3-angled. light colored, minute. @ Pa., S. and W. 



8 C. Inflexus Muhl. Culm:- clustered. 1 3', leaves setaceous; hds. 1 3; spk. very 



short (1 2''), crowded ; gls. 8 10, with a recurved bristle-point. (T) Shores. Com. 



9 C. acuiniiiatiiK Torr. Culm filiform or slender. 312'; hds. 17, each of CO flat 



obi. -ovate obtuse spikes 23" long ; glumes whitish, recurved at tip. @ 111. to La. 

 IOC. virens MX. Culm sharply rough-angled, 1^f; leaves keeled, 1 3f; heads CO, 

 of CO ovate 15-flwd. spikes; gls. greenish, merely acute ; ach. linear. "H Va., and S. 

 ft. i eg Vwjt, has smooth culms and spikes very densely packed. S. 



1 1 C. Drutnmondll Torr. Culm very rough, 6 15', obtuse-angled; hds. CO, dense, 

 spike oblong-linear, 40-50-fiowered, yellowish : glumes ovate, acute. Swamps. Fla. 



12 C. Hasp. .11 L. ft. lepto*. Culm 1 2f, leaves shorter, involucre 2-leaved, shorter 

 than the compound umbel ; spikes linear, acute, 6", 35 in a cluster ; glumes minute, 

 20 40, mncronate, tawny-brown ; achenia very minute, white, tumid. Swamps. S. 



13 C. deiitatuti Torr. Much like C. Haspan, but the involucre is 3- or 4-leaved, and 

 longer than the umbel ; glumes fewer (720), larger, the upper often long-pointed. 



14 C. Lecoiittl Torr. Culm and leaves 1 2f; umbel much compounded, with about 

 3 oblong, obtuse, flat silvery spikes on each peduncle ; glumes 20 40, obtuse, very 

 closely imbricated. 2{ Sandy coasts, Fla. A handsome sedge. 



I 5 C. fuscus L. Culms 3 6', leaves flat ; spk. lance-linear, 1 3", dark-red or brown, 



densely fascicled in many heads ; glumes round-ovate, closely imbricate. Phila. 

 16 C. compressus L. Culm tumid at base, 410', Ivs. shorter; spikes lance-linear, 

 in loose hds ; gls. 12 10, ov. -acuminate, acutely keeled and close-pressed. Pa., and S. 



II C. diver-gens Ktmth. Tufts 2 3', leaves longer; spikes lance-ovate, flat, acute, 

 1", 6-flowered, white, all in a single somewhat compound head. Fla. 



18 C. filiculmlg Vahl. Culm tuberous, very slender, 6 12'; leaves very narrow, 

 keeled ; spk. lance-lin., in 1 4 dense lids. ; gls. loose, 3 8, ovate ; ach. gray. y. Dry. 



1 9 C. Grayit Torr. Differs from No. 18 only in the looser heads of 68 linear spikes, 

 the glu/nes less scarious and less veiny, it Mass, to N. J. 



20 C. Sell welnitzil Terr. Culm rough-3-angled, 121'; leaves shorter ; umbel sim- 

 ple, rays 4 6, erect ; fls. large, in little spikes arranged close into cylindric-oblong 

 compound spikes, with setaceous bractlets. 2i Shores, N. Y. to Ark. 



21 C. rotund us L. ft. Hydra. Nut Grass. Culm 6' 2f, the leaves shorter; umbel 

 simple, rays 3 or 4, nearly equaling the invol. ; spikes in two rows on the rachis ; 

 gls. 14 24, veinlcss, purple-brown. 11 Va., and S. A rank and troublesome weed. 



22 C. E8CVI.ENTU8. Root producing ovoid tubers as large as chestnuts, eatable when 

 roasted (those of No. 23 very small) ; glumes veiny, yellow-brown, y. Eur. Cilt. 



23 t' pliymatbdcs Muhl. Culm 1 2f, with long Ivs. and invol. ; umliel simple .i 

 compound ; spk. linear, obtuse ; gls. veiny, 12 20, yellowish 4 Root creeping. 



24 <-'. strlgosiis L. Culm 1 3f; leaves broad-linear ; umbel dense, large, some com- 

 pound; rays 1 5'; spikes crowded, flattened, acute; glumes 8 18, tawny,- ovate, 

 acute, veined, much longer than the achenia. 2f Damp. Common. 



25 . steiiolepls Torr. Culm If 3f, smooth; leaves stiff, rough; rays 3 8; spikes 

 crowded. 67" ; glumes 5 8, lance-linear, spreading; seed slender, dull. 11 S. 



