358 ORDER 154. CYPERACE^K. 



3 C. micro dontns Torr. Calm and Ivs. slender; spk. numerous, crowded, lineat 



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

 )3. Uatfuii. Culm and leaves filiform ; epikes fewer, loose in the umbel. S-W. 



4 C. flavescens L. Culm and leaves 410' ; rays 24, short, the linear obtuse 



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



5 C. flavicomus MX. Culm 1 3f; involucre 3-6-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. 



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



umbel compound, involucre short ; spk. subulate ; gls. 1420, scarious. Swamps, S. 



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



eef-sile clusters ; spikes very many. G", teretish ; glumes 1530, yellow-brown ; inner 

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



8 C. inilexus Muhl. Culms 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. acumiimtus Torr. Culm filiform or slender, 3 12'; hds. 17, each of GO flat 



obl.-ovate obtuse spikes 2 3" long; glumes whitish, recurved at tip. 111. to La. 

 IOC. virens MX. Culm sharply rough-angled, 1 4f; leaves keeled, 1 3f; heads GO, 

 of Go ovate 15-flwd. spikes ; gls. greenish, merely acute ; ach. linear. 11 Va., and S. 

 /3. reg "** M *i has smooth culms and spikes very densely packed. S. 



11 C. Drummondii Torr. Culm very rough, 6 15 7 , obtuse-angled; hds. GO, dense, 

 spike oblong-linear, 40-50-flowered, yellowish ; glumes ovate, acute. Swamps. Fla. 



12 C. Haspau 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 miuute, 

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



1 3 C. den tat u* Torr. Much like C. Haspan, bat the involucre is 3- or 4-leaved, and 

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



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

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

 closely imbricated. U Sandy coasts, Fla. A handsome sedge. 



1 5 C. f uscus L. Culms 36', 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, 4 10', Ivs. shorter; spikes lance-linear, 

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



17 C. diverge ii Kunth. Tufts 2 'V, leaves longer; spikes lance-ovate, flat, acute, 

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



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

 keeled; spk. lance-lin., in 1 4 dense l.ds. ; gls. loose, " 8, ovate ; ach. gray. 2t Dry. 



19 C. Grayii Torr. Differs from No. 18 only in the looser heads of 68 linear spikes, 

 the glumes less t-x-arious and less veiny. 2f Mass, to N. J. 



20 C. Sell \veiii itzii Trr. Culm rouyh-3-angled, 1 2f; leaves shorter ; umbel sim- 

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

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



21 C. rotund us L. /3. Hydra. Nut Grass. Culm G'2f, the leaves shorter; umbel 

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

 gls. 14 24, veinless, purple-brown, li Va., and S. A rank and troublesome weed. 



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

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



23 C. phymatodes Muhl. Culm 1 2f, with long Ivs. and invol. ; umbel simple or 

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



24 t'. strigosns L. Culm 1 3f; leaves broad-linear ; umbel dense, large, some com- 

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

 acate, veined, much longer than the achenia. U Damp. Common. 



25 C. steiiolepis Torr. Culm H 3f, smooth; leaves stiff, rough; rays 3 8; spikee 

 crowded. 6 7" ; glumes 5 8, lance-linear, spreading; seed slender, dull. 11 S. 



