616 CYPERACE^. (sedge FAMILY.) 



* 11. — -1-4. Arenarke. 



C. arexXria, Linn. Extensively creeping, 1° high or less ; leaves very 

 narrow and very long-pointed, shorter than the culm ; head about V long, 

 dense or sometimes interrupted, ovoid or oblong ; spikes few to many, those 

 at the apex of the head usually staminate, the intermediate ones staminate at 

 the summit, the lowest entirely pistillate and subtended by a bract about 1' 

 long ; perigynium very strongly nerved on both faces, wing-margined above, 

 sharply long-toothed, about the length of the scale. — Sea-beaches near Nor- 

 folk, Va. (McMinn). (Adv. from Eu.) 



* 11. — -t- 5. Muhlenberg iance. 



H-t- Heads narrow, the spikes scattered (or often aggregated in C. muricata.) 



= Perigynium ahnost terete. 



109. C. tenella, Schkuhr. Exceedingly slender, 6'-2° high, in tufts; leaves 

 flat, soft, and weak, mosfly shorter than the culm; spikes 1-3-flowered, or 

 the terminal 4 - 6-tlowered, all distinct and scattered on the upper part of the 

 culm, the bracts obsolete or the lowest present and very short ; perigynium 

 elliptic-ovate, very plump, finely nerved, the minute beak entire, longer than 

 the white scale, usually at length splitting and exposing the blackish achene. 

 — Cold swamps, N. Eng. to Penu., and far westward ; common. (Eu.) 



= = Perigynium Jiattish. 



110. C. rosea, Sdikuhr. Always slender and weak, erect, 1-2^° high, 

 exceeding the narrow leaves; spikes 5-8, 6- 14-flowered, the upper 3-4 ag- 

 gregated, the otliers 3 - 9" apart, the lowest usually with a setaceous bract ; 

 perigynium lance-ovate, thin and shining, nerveless, scarcely margined, rough 

 on the edges above, perfectly squarrose, very green, about twice longer than 

 the translucent wliite scale. — Rich woods, N. Eng. to Minn, and Neb. ; fre- 

 quent. — Var. radiXta, Dewey. Lower and much more slender, the culms 

 sometimes almost capillary ; spikes 2 - 5, scattered, 2 - 4-flowered ; perigynium 

 mostly narrower and more ascending. Open places and drier woods ; common. 



Var. Texensis, Torr. Very slender but strict, 1° high or less; spikes 

 3-4, all contiguous or the lower ones approximate, 2 - 6-flowered ; perigynium 

 lanceolate, the base prominently spongy, smooth or nearly so, conspicuousb^ 

 divaricate. — Dry places, S. 111. (Schnerk), and southward. 



Var. retroflexa, Torr. Often rather stiff, 1 -H° high; spikes 4-8, the 

 upper ones aggregated, the lo\yer 1 or 2 separated and commonly subtended 

 by a conspicuous bract, often brownish ; perigynium ovate, smooth through- 

 out, very prominently corky and SAvollen at tlie base, which is frequently con- 

 tracted almost to a stipe, at maturity usually widely spreading or reflexed ; scale 

 brownish and sharp, at length deciduous. (C. retroflexa, J/hA/.) — Copses, 

 throughout; rare northward. 



111. C. sparganioides, Muhl. Stouter, stiff ; culm 2 -3° high; leaves 

 very broad (usually I' or more) and flat, their sheaths conspicuously clothing 

 the base of the culm ; spikes 6-10, the 2 or 3 upper ones contiguous, the remain- 

 der entirely separate, very green, oblong or short-cylindric, the lowest often 

 compound, all truncate at top ; perigynium ovate, wing-margined, rough on 

 the short beak, often obscurely nerved on the outer face, considerably longer 

 than the rough-pointed scale. — Rich woods ; frequent. 



C. MURICATA, L. Culm 1 -2° high, rough, longer than the narroAV leaves; 

 spikes 5-10, variously disposed, but usually some of them scattered, frequently 



