614 CYPERACE^. (sedge FAMILY.) 



§2. VtGNEA.— * 11. AcROARRHix.E. — -w 1. FxtidcB 



98. C. chordorhiza, Ehrh. Very extensively stoloniferous ; culm 

 mostly erect, 1 - 1^° long ; leaves involute, shorter than the culm ; perigyuium 

 globular, very strongly nerved, short-pointed and entire, about the length of 

 the acute scale. — Cold bogs and soft lake-borders, Vt. to Iowa, and north- 

 ward; infrequent. (Eu.) 



99. C. Stenoph:^lla, Wahl. Stiff, 3-8' high ; leaves involute and shorter 

 than the culm ; perigynium ovate, flat on the inner face, lightly nerved, grad- 

 ually contracted into a short and entire rough-edged beak, tightly enclosing 

 the achene, at maturity longer than the hyaline acutish scale. — Dry grounds, 

 Thayer Co., Neb. {Besseij) ; Emmet Co., Iowa {Cratty), and westward. (Eu.) 



* 11. — -1-2. Vulpmce. 

 ++ Beak shorter than or about as long as the bodi/ of the perigi/nium. 



100. C. COnjlincta, Boott. Strict but rather weak, U-3i° high; culm 

 soft and sharply triangular or nearly wing-angled, becoming perfectly flat 

 when pressed ; leaves soft, about 3" broad ; head 1 - 3' long, interrupted, often 

 nearly green, infrequently bearing a few setaceous bracts ; perigynium lance- 

 ovate, light colored, whitish and thickened below, the beak lightly notched 

 and roughish, about equalling or a little exceeding the cuspidate scale. — 

 Swales and glades, N. J., Ky., and westward ; usually rare. 



■*-*■ -^+ Beak twice the length of the bodij of the perigi/nhun or longer. 



101. C. stipata, Muhl. Stout, 1-3° high, in clumps; culm rather soft, 

 very sharp ; head 1-3' long, rarely somewhat compound at base, interrupted, 

 the lowest spikes often -|' long ; perigynium lanceolate, brown-nerved, the beak 

 toothed and roughish, about twice the length of the body, and much longer 

 than the scale. — Swales ; common and variable. 



102. C. crus-corvi, Shuttlew. Stout, glaucous, 2-3° high; culm 

 rough, at least above ; leaves flat and very wide ; head much branched and 

 compound, 3 - 6' long ; perigynium long-lanceolate, the short base very thick 

 and disk-like, the roughish and very slender beak thrice the length of the body 

 or more, 3-4 times the length of the inconspicuous scale. — Swamps, S. Minn 

 to Xeb. and Ky., and southward ; rare northward. 



* 11. — -t- 3. Midtlforce. 

 ++ Spikes conspicuously panicled. 



103. C. decOinp6sita, Muhl. Stout, exceedingly deep green, H-3° 

 high, in stools ; culm very obtusely angled, almost terete below ; leaves firm, 

 channelled below, longer than the culm ; head 2 - 4' long, the lower branches 

 ascending and 1-2' long ; perigynium very small, round-obovate, few-nerved, 

 hard and at maturity shining, the abrupt short beak entire or very nearly so ; 

 scale acute, about the length of the perigynium. — Swamps, N. Y. to Mich., 

 and southward ; local. 



•M- ■*-*■ Spikes in a simple or nearly simple head. 

 = Leaves very narrow (1" bi-oad or less), becoming more or less involute. 



104. C. teretiuseula, Gooden. Slender but mostly erect, \l-2^° high, 

 in loose stools ; culm rather obtuse, rough at the top, mostly longer than the 

 leaves ; head 1-2' long, compact or somewhat interrupted, narrow (|' wide or 



