CYPERACE^E. (SEDGE FAMILY.) 619 



Var. polystkchya, Boott. Erect and mostly strict, not glaucous, 1-| - 2| 

 high, scarcely tufted ; leaves very lax and exceeding the culm ; spikes oblong, 

 more or less aggregated in an oblong interrupted head, the lowest 1 or 2 sub- 

 tended by short scale-like bracts ; perigynium somewhat spreading. (C. arcta, 

 Boott.) Low woods, N. New Eng. to N. Minn. ; rare. Kesembles C. echinata, 

 var. cephalantha. 



120. C. Norv^gica, Willd. Low and stiff, but rather slender, 1 high 

 or less ; leaves very narrow, mostly shorter than the culm ; spikes 3-5, some- 

 what scattered, brown, globular or oblong, compactly many-flowered, the 

 terminal one long-contracted below with the staminate flowers ; perigynium 

 very short-ovate, thick, the beak rough, a little longer than the very obtuse 

 S.-ale. Salt marshes, Maine, and northward, rare. (Eu.) 



121. C. tenuiflbra, Wahl. Very slender and diffuse, 1 - 1 high, in 

 tufts ; leaves very narrow and lax, shorter than the filiform culm ; spikes 2 - 

 4, all loosely few-flowered and silvery-green, and aggregated into a small 

 globular head ; perigynium elliptic, obscurely nerved, smooth, beakless, spread- 

 ing, about the length of the white thin scale. Bogs, N. New Eng. to N. 

 Minn.; local. (Eu.) 



b. Bracts much prolonged, the lowest 2-3' long. 



122. C. trisp^rma, Dewey. (PL 6, fig. 1-5.) Exceedingly slender, in 

 small and loose tufts, the weak reclining culms 1-2 long ; leaves soft and 

 narrow, shorter than the culm ; spikes 2-3, 1 - 3' apart, silvery-green, 2-3- 

 flowered ; perigynium very thin, finely nerved, the beak entire or nearly so ; 

 scale acute, very thin, usually shorter than the perigynium. Cold bogs, 

 throughout ; common northward. 



= = Perigynium ovate-lanceolate to linear-lanceolate. 



123. C. Deweykna, Schwein. Weak, l-lj high; leaves flat and soft, 

 shorter than the culm, yellowish-green ; spikes 3-6, mostly oblong or some- 

 times but 2 - 3-flowered, loose, the upper ones contiguous but the lower 1 or 2 

 usually considerably separated on the zigzag rhachis and mostly subtended 

 by a bract, all silvery-green ; perigynium ovate-lanceolate or narrower, very 

 thin in texture, nerveless, somewhat thickened below on the outer face, the 

 long beak rough ; scale very thin, acute or cuspidate, about the length of the 

 perigynium. Dry woods ; common. 



124. C. bromoides, Schkuhr. Lax, 1-2 high, in dense stools; leaves 

 very narrow, about as long as the culm ; staminate flowers variously situated 

 in the head, sometimes a few spikes wholly sterile, rarely the plants dkecious ; 

 spikes 3-6, oblong or short-cylindric, erect, silvery-tawny or brown; peri- 

 gynium linear-lanceolate, firm especially at the base, prominently nerved, the 

 long and roughened beak toothed ; scale sharp, shorter than the perigynium. 

 Open bogs ; common. 



* 12. H- 2. OvMes. 



w- Perigynium ovate-lanceolate, with winged margins. 



125. C. SJLCC&ta, Dewey. Extensively creeping, 1-2 high, erect ; leaves 

 firm, narrow, about the length of the culm ; staminate flowers variously situ- 

 ated, usually some of the spikes wholly sterile ; spikes 3 - 5, aggregated or 

 separated, ovoid or short-oblong, silvery-brown ; perigynium firm, nerved on 



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