CYPERACEAE. 19 1 



androgynous, the staminate and pistillate flowers each 2-5; perigynium green, 

 narrow^ scarcely inflated. 6-8 mm. long, about 1 mm. in diameter, several -nerved, 

 tapering into a slender or almost subulate beak, strongly reflexed and readily detach- 

 able when mature, 2-3 times longer than the deciduous lanceolate or ovate scale; 

 stigmas 3. In bogs, Newf. to Alaska, Mass., Penn., Mich, and Wash. June-Aug. 



Pistillate spikes ovoid or globose, few-many-flowered. 



Perigynia subulate, reflexed when mature. 2. C. Collinsii. 



Perigynia conic or ovoid, not reflexed. 



Plants yellow or yellowish ; perigynia little inflated. 



Leaves 2-4 mm. wide ; staminate spikes sessile. 3. C. abacta. 



Leaves 4-12 mm. wide ; staminate spike mostly stalked. 4. C./olliculata, 

 Plants green ; perigynia much inflated ; staminate spike stalked. 



Leaves 4-6 mm. wide ; heads loosely flowered. 5. C. intumescens* 



Leaves 6-10 mm. wide ; heads globose, dense. 6. C. Asa-Grayi. 



Pistillate spikes oblong or cylindric, densely many-flowered. 

 Pistillate spikes oblong ; achene longer than thick. 



Perigynia several-nerved, shining; leaves 2-4 mm. wide. 7. C. Louisianica. 



Perigynia many-nerved, dull ; leaves 4-10 mm. wide. 8. C. lupulina. 



Pistillate spikes cylindric ; achene not longer than thick. 



Perigynia yellowish, tapering into a beak twice as long as the body. 



9. C. lupuliformis. 

 Perigynia greenish-brown, abruptly narrowed into a beak 2-3 times as long as 

 the body. 10. C. grandis. 



2. Carex Collinsii Nutt. Collins' Sedge. (I. F. f. 672.) Glabrous; culms 

 slender, erect or reclining, 1 .5-5 dm. long. Leaves narrow, the broadest about 5 mm. 

 wide; staminate spike stalked; pistillate spikes 2-4, distant, 2-8-flowered; bracts 

 similar to the leaves; perigynia light green, scarcely inflated, subulate, 1-1.4 cm. 

 long, tapering into an almost filiform beak, faintly many-nerved, strongly reflexed 

 when mature, about 3 times as long as the lanceolate-acuminate persistent scale; 

 stigmas 3. In bogs, R. I. to E. Penn. and Ga. June-Aug. 



3. Carex abacta Bailey. Yellowish Sedge. (I. F. f. 673.) Glabrous, 

 yellowish; culm rather stiff, slender, 0.2-0.5 m - high* Leaves narrow, the broadest 

 about 4 mm. wide, the uppermost often exceeding the culm; staminate spike sessile; 

 pistillate spikes 2 or 3, several-flowered, the upper sessile or very nearly so; bracts 

 similar to the leaves; perigynia slender, narrow, scarcely inflated, tapering into a 

 subulate 2-toothed beak, 1— 1.5 cm. long, less than 2 mm. thick, strongly many- 

 nerved, about twice as long as the acute or acuminate scale. In bogs and wet 

 meadows, N:*wf. to N. H., N. Y. and Mich. Also in Japan. July-Sept. 



4. Carex folliculata L. Long Sedge. (I. F. f. 674.) Glabrous; light 

 green or yellowish; culm erect or reclining, 0.4-1 m. long. Leaves elongated, 

 often 12 mm. wide; pistillate spikes 2-4, usually distant, all except the uppermost 

 slender-stalked, the lower often nodding; bracts commonly overtopping the spikes; 

 perigynia ovoid, somewhat inflated, green, rather prominently many-veined, 12- 

 16 mm. long, about 2 mm. in diameter near the base, tapering from below the 

 middle into a slender 2-toothed beak, longer than the awned scarious-margined 

 persistent scale; teeth of the perigynium nearly erect; stigmas 3. In swamps and 

 wet woods, Newf. to Md., Mich, and W. Va. Probably extends further south, but 

 there mostly represented by the var. australis Bailey. May-Sept. 



5. Carex intumescens Rudge. Bladder Sedge. (I. F. f. 675.) Gla- 

 brous; culms slender, commonly tufted, 0.4-0.9 m. high. Leaves elongated, dark 

 green, roughish, 3-6 mm. wide; bracts similar, overtopping the culm; staminate 

 spike mostly long-stalked; pistillate spikes I -3, sessile or short-stalked, globose or 

 ovoid; perigynia 1-30, spreading or the upper erect, 12-20 mm. long, much in- 

 flated, about 6 mm. in diameter above the base, many -nerved, tapering into a 

 subulate 2-toothed beak, the teeth somewhat spreading; scales narrowly lanceolate, 

 acuminate or aristate, about one-half as long as the perigynia; stigmas 3. In 

 swamps, bogs and wet woods, Newf. to Manitoba, Fla. and La. May-Oct. 



Carex intumescens Ferndldi Bailey. Perigynia narrower, 1-5 in each spike, all 

 erect or slightly spreading. Me. to N. Y. and Mass. 



6. Carex Asa-Grayi Bailey. Gray's Sedge. (I. F. f. 676.) Glabrous, 

 culms stout, 0.5-0.9 m. tall. Leaves elongated, dark green, 6-9 mm. wide; bracts 



