47. Carex Thurberi Dewey. 



Cespitose from stout rootstocks; culms 6-12 dm. high, phyllopodic, erect, stout, 

 shorter than the leaves and bracts, sharply triangular, reddish-tinged at the base, 

 the lower sheaths breaking and becoming filamentose; leaves 5 to 10 to a culm, 

 obscurely septate-nodulose, the blades flat with revolute margins, thin but rather 

 stiff, 4-8 mm. wide, long-attenuate, very rough toward the apex; sheaths sparsely 

 hispidulous dorsally, concave and short-hispid at the mouth, the short ligule much 

 wider than long; terminal spike staminate, erect, short-peduncled, linear, 4-8 cm. 

 long, 3-5 mm. wide; pistillate spikes 3 or 4, approximate or more or less sepa- 

 rate, drooping or the upper weakly erect on rough slender peduncles mostly 

 shorter (except the lowest) than the spikes, the spikes oblong-cylindric or cylindric, 

 3.5-7 cm. long, 8-10 mm. wide, densely 50- to 100-flowered, the perigynia 

 ascending or spreading-ascending; bracts leaflike, sheathless or very nearly so, 

 much-exceeding the inflorescence; scales ovate, often emarginate, strongly rough- 

 awned, the body large, ciliate-serrulate above, hyaline and slightly reddish-brown- 

 tinged, the green center three-nerved, nearly as wide as but much shorter than the 

 perigynia; perigynia elliptic-ovoid, 4-5 mm. long, 1.5 mm. wide, slightly inflated, 

 suborbicular to obscurely triangular in cross section, submembranaceous, puncti- 

 culate, yellowish-green, finely several-ribbed, rounded at the short-stipitate base, 

 tapering into a smooth strongly bidentate beak 1.5 mm. long, the slender stiff 

 teeth slightly spreading, 0.5-0.75 mm. long; achenes trigonous with blunt angles, 

 oblong-obovoid, about 1.75 mm. long and 0.75 mm. wide, substipitate, continuous 

 with the slender abruptly bent persistent style. 



In moist or wet ravines and swampy habitats, in Ariz. (Coconino, Gila, Cochise, 

 Santa Cruz, and Pima cos.); Ariz, to Guat.; W.I. 



48. Carex lurida Wahl. Fig. 270. 



Tufted perennial with very short rhizomes; culms 3-10 dm. long, 1.5-6.5 mm. 

 thick, erect, leafy; basal sheaths brown (occasionally faintly reddish); blades 4-10 

 mm. broad; spikes 3 to 5. mostly overlapping or occasionally the lower 1 or 2 

 slightly removed; terminal spike staminate, erect, 3-6 cm. long, 1-2 mm. thick; 

 rest of spikes pistillate, nearly sessile (or the lower occasionally on flexuous 

 peduncles to 19 cm. long), often arcuate-nodding, the lowest 25-40 (-60) mm. 

 long, 14-18 (-20) mm. thick including beaks, with 50 to 80 (to 100) close some- 

 what ascending perigynia; bracts foliaceous, sheathing, the blade of the'lowest one 

 much-surpassing the entire inflorescence; the scales about as long as the bodies of 

 the perigynia and subulate or awnlike in their distal part; perigynia ampule-shaped, 

 7-11 mm. long, the bodies ovoid or obovoid, 2.3 mm. thick, 4-6 mm. long, in- 

 flated, membranous, olive-green, drying to olive-brown or olive-stramineous, with 

 8 to 1 1 nerves (2 slightly stronger than the rest) much narrower than the internerve 

 spaces, basally tapered and shortly rounded, apically tapered or long-conic and 

 passing gradually into the linear-subulate bidentate beak; achene triangular, about 

 2.5 mm. long, 1.5 mm. wide, granular, continuous with the sinous-flexuous per- 

 sistent style the lower half of which is texturally similar to the achene. 



Wet meadows, marshes, seepage, edge of streams and ponds in sand and mud, 

 in Okla. (McCurtain and LeFlore cos.) and e. Tex., May-June; e. temp. N.A. w. 

 to Minn., Mo., Okla. and Tex.; also Ver. 



49. Carex vesicaria L. Inflated sedge. Fig. 271. 



Rhizomes short-creeping, stout; culms 3-9 dm. tall, sharply triangular and 

 rough above, the lower leaves more or less bladeless; leaf blades flat, 2-6 mm. 

 wide, more or less strongly nodulose on abaxial surface; staminate spikes 2 to 4, 

 2-4 cm. long, 2.5-4 mm. wide, the upper one peduncled, the lateral ones sessile; 

 pistillate spikes 1 to 3 (usually 2), 2-7.5 cm. long, 5-15 mm. wide, oblong- 



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