This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol1", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Glabrous, culms phyllopodic, from long rootstocks, rather stout, smooth or rough above, erect, 1°-3° tall. Leaves often equalling the culm, 1"~3" wide, their margins revolute, smooth, their sheaths more or less nodulose; bracts similar, not spathe-like, usually overtopping the spikes; staminate spikes 1-3, stalked; pistillate spikes 2-4, approximate, narrowly cylindric, often staminate at the summit, 1'-2 1/2' long, erect, the upper often sessile, the lower stalked; perigynia elliptic, coriaceous, green, nerveless or 2-4-nerved, with a very short entire beak; scales dark-purple, brownish or chestnut with a green center, lanceolate, pale, acuminate or abruptly contracted into a serrate awn, much longer than the perigynia; stigmas 2.
Glabrous, stoloniferous, culm stout, erect, sharply 3-angled, rough above, 1 1/2°-3° tall. Leaves smooth, 1"-4" wide, the basal shorter than or equalling the culm, the upper ones and the lower bract shorter; staminate spikes 2-4, stalked; pistillate spikes 2-5, all filiform-stalked and drooping, densely flowered, i'-3 long, 3"-4 1/2" in diameter; perigynia oblong or oval, puncticulate, green, several-nerved, 1 1/2" long, tipped with a very short entire beak; scales purple-brown, ascending, lanceolate, acute, acuminate or even cuspidate, from little to 2 or 3 times longer than the perigynia; stigmas 2.
Arctic America from Greenland to Alaska, south along the coast to Oregon and Washington. Europe and Asia. Summer.
C. maritima Mueller, Fl. Dan. 4: fasc. 12, 5. pl. 703. 1777.
Glabrous, light green, culms aphyllopodic, rather stout, erect, sharply 3-angled, smooth, or roughish above, little fibrillose at base, 1°-2 1/2° tall, from stout stoloniferous rootstocks. Leaves 1 1/2-5" wide, roughish on the margins and midvein, rarely overtopping the culm, sterile culm-leaves longer; lower bracts exceeding culm; staminate spikes 1-3, slender-stalked; pistillate spikes 2-4, ovoid- to linear-oblong, often staminate at the summit, densely many-flowered, not flexuous, I'-3' long, 4"-8" thick, drooping or widely spreading on filiform stalks; perigynia oval or nearly orbicular, ascending, pale, biconvex, not inflated, 1 1/2" long, few-nerved, tipped with a very short and nearly or quite entire beak; scales ascending, green, lanceolate-subulate, ciliate-scabrous, 2-8 times as long as the perigynia; stigmas 2.
In salt meadows. Newfoundland and Labrador to Massachusetts. Also in Europe. June-Aug.