[++] Sheaths green.
[=] Perigynium mostly obscurely triangular, the beak very prominent.
68. C. laxiflòra, Lam. Slender but mostly erect, 1–2° high; leaves rarely over 2´´ wide, rather soft; staminate spike peduncled or at least conspicuous; pistillate spikes 2–4, scattered, peduncled or the upper one sessile, loosely flowered, cylindric or sometimes reduced to short-oblong, erect or the lower loosely spreading; perigynium obovate, conspicuously nerved, the short entire beak much bent or recurved; scale thin and white, blunt or cuspidate, mostly shorter than the perigynium.—Grassy places, throughout; common. Exceedingly variable.—Var. vàrians, Bailey. Mostly stouter than the type, the leaves broader; pistillate spikes ½–1´ long, the two upper more or less contiguous to the staminate spike and sessile or nearly so; bracts leafy and prolonged.—Copses and grassy places, throughout; common. Counterfeits var. patulifolia.—Var. striátula, Carey. Diffuse; pistillate spikes rarely over ½´ long, the upper sessile and aggregated about the inconspicuous staminate spike, the lowest usually long-exserted. Grassy places, throughout; very common.—Var. latifòlia, Boott. Rather low; leaves ½´ broad or more; staminate spike sessile or very nearly so; pistillate spikes cylindric and loose, the upper one or two contiguous; bracts very broad. Deep rich woods, E. Mass. (Deane) to Penn. and Mich.; common westward.—Var. patulifòlia, Carey. Glaucous; leaves 3´´ broad or more; staminate spike prominent, mostly stalked; pistillate spikes long and alternately flowered, scattered and peduncled; perigynium (as in the following varieties) elliptic, attenuate at both ends, mostly less prominently nerved, and the beak not strongly recurved. Open places, N. Eng. to Mich., and southward; frequent.—Var. divaricàta, Bailey. Tall and stout; leaves narrower; staminate spike large and stalked; pistillate spikes scattered, all but the upper one prominently peduncled, long; perigynium very large, divaricate, triangular, contracted into a stipe-like base at least half as long as the body. Near Washington, Vasey.—Var. stylofléxa, Boott. Very weak and slender; leaves 2´´ wide or less; staminate spike usually peduncled; pistillate 2–3, scattered, few-flowered, lowest drooping; perigynium very long-pointed. S. E. Penn., and southward; frequent.
[=][=] Perigynium sharply triangular, short, and mostly not prominently beaked.
a. Spikes drooping or flexuose.
69. C. digitàlis, Willd. Very slender, bright green, tufted, 6–18´ high; leaves very narrow (1–2´´ wide); staminate spike short stalked; pistillate spikes 2–4, all on filiform stalks and all but the upper widely spreading or drooping, linear, alternately flowered; perigynium very small, impressed-nerved, longer than the acute whitish scale.—Dryish woods and glades, N. Eng. to Mich., and southward; frequent.—Var. copulàta, Bailey. Leaves much broader, and the culms weak and reclined; spikes heavier and mostly shorter; perigynium larger, very sharp. Rich woods, central Mich., and probably elsewhere westward.
70. C. laxicúlmis, Schwein. Differs from the variety of n. 69 chiefly in its more cespitose habit, its densely glaucous-blue covering, very slender culm, and very long and filiform peduncles. (C. retrocurva, Dewey.)—Glades, N. Eng. to Mich. and Va.; rare westward.
b. Spikes erect.
71. C. ptychocárpa, Steudel. Low, glaucous, 3–10´ high; leaves flat and rather broad (2´´ or more), much exceeding the culm; bracts leafy and much prolonged; staminate spike very small and sessile, mostly overtopped by the upper pistillate spike; pistillate spikes 2–3, sessile or short-stalked or rarely the lowest long-peduncled, erect; perigynium tawny, much as in n. 69, twice longer than the very thin obtuse scale.—Low grounds or swamps, E. Mass., N. J., Del., and southward; local.
72. C. platyphýlla, Carey. Low, spreading, glaucous, 6–12´ high; leaves ½´ broad or more, mostly shorter than the culms; bracts with thin and sharp-pointed leaf-like tips 1–2´ long; staminate spike stalked; pistillate spikes 2–3, scattered, all more or less peduncled, alternately 2–10-flowered; perigynium short, strongly many-striate, about the length of the acute or cuspidate scale.—Rich shady woods and banks, N. Eng. to Mich., and southward to Va.; mostly local.