[=] Head silvery-brown, silvery-green, or silvery-whitish.
129. C. adústa, Boott. Very stiff and stout, 1½–2½° high, in dense tufts; head very heavy, erect, varying from globular to oblong, silvery-brown; spikes 5–10, globular and heavy, all aggregated or sometimes distinct, the lowest 1 or 2 subtended by a short and very broad-based, nerved and pointed bract; perigynium broadly ovate, wingless or very nearly so, plump, shining, nerved on the outer face but nerveless on the inner, filled by the large achene; scale acute, about the length of the perigynium. (C. pinguis, Bailey.)—Dry and mostly hard soils, Mt. Desert, Maine (Greenleaf), and northward, and Crawford Co., Mich. (Bailey), to N. Minn., and far northwestward; local.
130. C. fœ̀nea, Willd. Slender, erect or the top of the culm flexuose, 1–2° high; head long and weak, often nodding; spikes 5–8, small, nearly globular and much contracted below, silvery-green, alternately disposed; perigynium varying from ovate to long-ovate, very thin, much longer than the small achene, prominently rough-margined, strongly many-nerved on both faces, especially on the small inner face; bracts entirely wanting or inconspicuous. (C. adusta, last ed.)—Dryish copses, N. Eng. to Penn. and Minn.; not common.—Var. perpléxa, Bailey. Mostly taller and stouter; spikes larger and less attenuated or even truncate below, approximate or even aggregated, the head erect or nearly so and the lowest bract occasionally prominent; perigynium thicker and firmer in texture. N. Eng. to Minn.; infrequent.
131. C. silícea, Olney. Stiff, 1–2° high, in clumps; leaves very narrow, becoming involute, not exceeding the culm; head 1–3´ long, usually flexuose or nodding above the middle at maturity; spikes 5–8, silvery-white or silvery-tawny at full maturity, all more or less separated, ovate, conspicuously contracted below and cone-shaped above, erect on the culm; perigynium very broad-ovate and very thin, obscurely nerved, appressed, about as long as the acute colorless scale. (C. fœnea, var. sabulonum, last ed.; C. straminea, var. moniliformis, Tuckerm.)—Sands of the sea-shore, Maine to N. J.; frequent.
[=][=] Head dull brown or green (usually somewhat silvery in var. fœnea of n. 132).
132. C. stramínea, Willd. Very slender, erect, but the top of the culm often flexuose, 1–3° high; leaves narrow and long-pointed, stiff, shorter than the culm; spikes 3–8, tawny, very small (2–3´´ broad), globular or sometimes a little tapering below from the presence of many staminate flowers, usually all entirely distinct on the very slender, often zigzag or flexuose rhachis; bracts none, or only the lowest conspicuous; perigynium small and ovate, nerved on both faces but never unusually prominently nerved on the inner face (as is the perigynium of n. 130), the points spreading and rather conspicuous; scale acute, about the length of the perigynium. (C. straminea, var. tenera, last ed.)—Dryish copses and fields; common. Immensely variable.
Var. mirábilis, Tuckerm. Culm long and mostly weak, often 4° high, much longer than the loose leaves; spikes 4–8, larger, usually all contiguous or occasionally the lowest 1 or 2 separate, spreading, loosely flowered, tawny or frequently greenish; perigynium narrowly ovate, thin, longer than the scale, the points much spreading and very conspicuous. (C. mirabilis, Dewey.)—Shady places, throughout; frequent.
Var. brèvior, Dewey. (Pl. 6, fig. 6–10.) Culm always stiff, 1½–2½° high, longer than the stiff long-pointed leaves; spikes 3–8, all distinct, contiguous or more or less separated, large (3–5´´ broad), globular, the head always short and erect; perigynium orbicular or ovate-orbicular, often cordate at base, mostly very broadly winged. (C. straminea, and vars. typica, hyalina, and Meadii, last ed.)—Dry soils, throughout; common.
Var. apérta, Boott. Culm slender but strict below the head, 1–2° high, growing in dense tufts; leaves very narrow, usually much shorter than the culm; spikes 4–6, large, heavy, much contracted below, usually all separated, becoming rusty, disposed in a weak or nodding head; perigynium narrowly ovate.—Bogs, throughout; rare westward. Transition to n. 128, from which the ovate perigynia distinguish it.
Var. invìsa, W. Boott. Culm very slender, weak above; leaves very narrow with exceedingly long thin points, about the length of the culm; spikes small (3´´ broad or less), ovate, variously disposed in dense or open heads or sometimes the lowest remote or even subradical, rusty, the lower ones subtended by filiform bracts 2–5´ long.—Swales near the sea-board, Maine to Del.; infrequent. Apt to be confounded with n. 128.