56 CYPEEACEAE. 



blades usually less than 2 mm. wide : sheaths without conspicuous white band : 

 bracts narrow and bristle-form : spikes in a monilif orm flexuous head, 3-9, 

 ovoid, 7-16 mm. long, commonly clavate at base: scales lanceolate, long-acumi- 

 nate or aristate, narrower than but nearly equalling perigynia : perigynia ascend- 

 ing, narrowly to broadly ovate, 4-6 mm. long, 2-3 mm. wide, thin, strongly 

 about 10-nerved on each face^ brownish at maturity, strongly wing-margined, 

 the rough bidentate beak half length of body. — S. Occasional, in wet meadows 

 and swamps. — Schists. — Spr. 



21. C. foenea Wilkl. Culms 3-10 dm. tall, erect or nodding, little roughened 

 above, exceeding leaves: leaf -blades 2^ mm. wide: sheaths with conspicuous 

 white band: bracts short or wanting: spikes 4-15, in a monilif orm or flexuous 

 head, subglobose, narrowed at base, 6-18 mm. long^ 5-6 mm. wide : scales 

 silvery-hyaline, ovate, acute to acuminate, about equalling perigynia and con- 

 cealing them: perigynia ovate, appressed or loosely ascending in age, 3-4.5 mm. 

 long, about 2 mm. wide, narrowly wing-margined, strongly several-nerved on 

 both faces, tapering into a short rough 2-toothed beak half length of body. — 

 S. Frequent, in rocky woods. — Schists. — Sum. 



22. C. Willdenovii Schk. Leaves glabrous and pale-green, often 3-6 dm. long, 

 much overtopping the spikes; blades 2-3 mm. wide, the lowest reduced to 

 sheaths: culms 2-25 cm. high: spikes 1-5, androgynous, or sometimes completely 

 staminate (the pistillate flowers usually 3-10), about 1.2 cm. long, appearing 

 nearly basal, one of them or more on long filiform stalks: scales lanceolate, 

 acute, acuminate or awned, hyaline-margined, finely several-nerved, the lower 

 1 or 2 commonly bract-like: body of the perigynium oblong, smooth, 2-3 mm. 

 long, narrowed into a 2-edged rough beak of about its own length. — M. Rare, 

 in thickets. — Limestones. — Spr. 



23. C. Jamesii Schwein. Similar to the next preceding species, but the leaf- 

 blades rather narrower, soft, spreading or ascending: spikes androgynous, the 

 terminal staminate portion slender, the pistillate flowers only 1-4 and slightly 

 separated: lower scales bract-like, the upper shorter and sometimes not exceeding 

 the perigynia: body of the perigynium globose, 2 mm. in diameter, abruptly 

 tipped by a subulate rough beak of more than its own length. • — M. Rather 

 rare, on dry banks and in thickets. — Limestones. — Spr. 



24. C, leptalea Wahl. Leaves light-green and glabrous; blades not over 0.5 

 mm. wide: culms filiform, smooth, 1.5-6 dm. long: spike solitary, terminal, 

 androgynous, linear, 4-16 mm. long: stigmas 3: perigynia few, linear-oblong, 

 3.5-5 mm. long, light-green, many-nerved, obtuse and beakless: scales mem- 

 branous, the lowest sometimes becoming bract-like. — M. E. Rare, in swamps 

 and low grounds. — Limestones^ quartzite. — Spr. and sum, 



25. C. communis Bailey. Plants not stoloniferous. Leaves light-green, shorter 

 than the culms, the lower reduced to scarcely fibrinous sheaths; blades 2^ mm. 

 wide: culms slender, roughish above, 1.5-5 dm. long: lower bract 0.6-5 cm. 

 long: staminate spike short-stalked, 4-25 mm. long: pistillate spikes 2-4, short- 

 oblong, 3-10-flowered: scales green, ovate, mostly acute: perigynia obovoid, 

 rather less than 2 mm. long, pale, pubescent, each with a subulate 2-toothed 

 beak i the length of the body. [C. pedicellate (Dewey) Britton.] — Rather 

 rare, in dry soil. — Spr. and sum. 



26. C. pennsylvanica Lam. Plants stoloniferous. Leaves dark-green or dull- 

 green, the lower blade-bearing; blades 1-3 mm. wide, the old sheaths persistent 

 and fibrillose: culms 1.5-6 dm. tall: lower bract rarely over 1 cm. long: 

 staminate spike sessile or very short-stalked, 12-24 cm. long: pistillate spikes 

 1-4, short-oblong, 4-20-flowered, sessile: scales ovate, purplish, acute or cuspi- 

 date: perigynia obovoid, about 2 mm. long, pubescent, 1-ribbed on each side, 

 each with a 2-toothed beak about I the length of the body or in some forms 

 longer. — Common, in dry soil. — Spr. 



