598 CYPERACE^E. (SEDGE FAMILY.) 



flat, generally sparsely hairy and the sheaths very hirsute, rarely smooth; 

 spikes 2-3, distant, more or less shortly-peduncled, erect or nearly so, 1|' long 

 or less and rather loose ; perigynium long-ovate, nerved, soft-hairy, the promi- 

 nent beak slenderly toothed ; scale thin and green-nerved, awned, mostly a 

 little shorter. E. Mass, to central N. Y. and Penn. (Nat. from Eu.) 



* 2. -t-4. PaludbsK. 

 -* Teeth slender, mostly spreading. 



28. C. trichocarpa, Muhl. Stout and tall, 2-3 high; culm sharply 

 angled, rough above ; leaves very numerous, flat and very rough, but not 

 hairy, much exceeding the culm ; spikes 2-5, scattered, the lower stalked 

 and more or less spreading, long and heavy (1 -4') but loosely flowered at 

 base ; perigynium long-ovate, rnany-costate, sparsely short-hairy, about twice 

 as long as the membranaceous, acute or acuminate scale. Marshes ; frequent. 



Var. IMBERBIS, Gray. Mostly smaller throughout; perigynium smooth ; 

 scales usually sharper and longer. Drier places, N. Y. to Mo. ; infrequent. 



Var. Deweyi, Bailey. Leaves narrower, often becoming somewhat invo- 

 lute, smoother; spikes short (seldom over IV long), all but the lowest one 

 sessile ; perigynium smooth, thick in texture, becoming polished with age, the 

 nerves impressed ; scales sharp, mostly a little shorter than the perigynium. 



Dakota (Seymour), and northwestward. Resembles small forms of n. 29. 

 Var. aristata, Bailey. Mostly stouter ; leaves more or less hairy on the 



under surface and sheaths ; perigynium usually longer, smooth, the teeth longer 

 and more spreading. (C. aristata, R. Br.) N. Eng. to Minn. ; rare eastward. 



+* ++ Teeth short, erect or very nearly so. 



29. C. riparia, W. Curtis. Very large and stout, 2-4 high, stolonifer- 

 ous; leaves mostly broad, flat, rough, glaucous, much longer than the sharply 

 angled culm ; spikes 2-4, scattered and all more or less peduncled, the lowest 

 often very long-stalked, varying from almost globular in starved plants to 3- 

 4' long, erect or the lower somewhat drooping, loosely flowered below ; peri- 

 gynium ovate-lanceolate, coriaceous, rather lightly many-nerved, becoming pol- 

 ished, the beak short and thick ; scale varying from blunt to awned, shorter or 

 longer than the perigynium. Swales: common. (Eu.) 



C. ACUTIFORMIS, Ehrh. Stout, 2-3 high; culm thick and sharp, mostly 

 smooth ; leaves broad, flat and glaucous, much prolonged ; spikes 3 -5, all but 

 the uppermost peduncled, spreading or drooping, narrowly cylindric (2 - 3' 

 long), loosely flowered below ; perigynium ovate, very strougly many-nerved, 

 the short beak slightly toothed ; scale rough-awned and longer than the peri- 

 gynium. (C. paludosa, Gooden.) Swales, Dorchester, and New Bedford, 

 Mass (Nat. from Eu.) The former station has been recently destroyed. 



* 3. MICRORHYNCHJE. -i- 1. AtratcE. 

 M- Alpine ; plant small. 



30. C. alpina, Swartz. Small and slender, --2 high; culm thin and 

 obtuse, smooth or roughish, naked above ; leaves narrow and flat, shorter than 

 the culm ; spikes commonly 3, sometimes 2 or 4, aggregated, globular and 

 very small, all closely sessile or rarely the lowest exceedingly short-stalked ; 

 perigynium orbicular or obovate, nerveless or nearly so, the short beak slightly 

 notched, a little longer than the ovate and black mostly obtuse scale. Isle 

 Royale, L. Superior. (Eu.) 



