140 CYPERACEAE 



42. HiBTAE Tuckerm. Culms stout, leafy. Rootstocks with long stolons. 

 Leaves septate-nodulose. Spikes 3-10, the upper 1-5 staminate, slender, the 

 others pistillate, many-flowered, erect. Bracts leaf-like, equalling or exceeding 

 the culm, often sheathing. Pistillate scales acute or aristate, ovate or lanceolate. 

 Perigj'nia mostly ascending, coriaceous, ovoid or oblong-ovoid, somewhat in- 

 flated, nearly orbicular in cross-section, many-nerved, often hairy, round-taper- 

 ing at the base, tapering into a bidentate beak. Achenes triangular, often stipi- 

 tate, the faces flat or deeply concave, apiculate, continuous with the straight or 

 slightly flexuous slender style. Stigmas 3. 



142. C. lacustris Willd. Culms stout, purplish-tinged and filamentose at 

 the base, 6-12 dm. high; leaf-blades 5-12 mm. wide, somewhat glaucous; stam- 

 inate spikes 1-5, slender; pistillate spikes 2-5, 3-10 cm. long, 1 cm. wide; scales 

 purpUsh tinged, acute to aristate; perigynia ovoid, 6 mm. long, 2.5 mm. wide, 

 strongly nerved. In swamps: Newf. — Del. — la. — Man. — Ida. Boreal. Je-Jl. 



143. C. lanuginosa Michx. Cuhus stoutish, more or less reddened and 

 filamentose at the base, 6-9 dm. high, sharp-angled and rough above; staminate 

 spikes 1-3, distant; pistillate spikes 1-3, 1-5 cm. long, 5-7 mm. wide; scales 

 acuminate or aristate; perigynia ovoid, the beak bidentate. C. Watsoni Olney. 

 Swampy places: N.S.—D.C.— Mo.— N.M.— Calif.— B.C. Plain— Mont. Je- 

 Jl. 



144. C. lasiocarpa Ehrh. Culms slender but stiff, strongly reddened and 

 filamentose at the base, 6-9 dm. high, obtusely angled, smooth; staminate spikes 

 1-3, distant; pistillate spikes 1-3, 1-5 cm. long, 5-7 mm. wide; scales acute or 

 short-awned; perigynia oval-ovoid, 2 mm. wide, the beak bidentate. C. fili- 

 /orms Auth., not L. Swamps: Newf. — N.J. — la. — ^Colo. — Ida. — B.C.; Eurasia. 

 Plain — Submont. 



145. C. Houghtonii Torr. Long-stoloniferous; culms stoutish, 3-8 dm. 

 high; leaf-blades 3-7 mm. wide; staminate spikes 1-3, distant; pistillate spikes 

 2 or 3, 1-4 cm. long, 7-12 mm. wide, rather loosely 15-35-flowered; scales lance- 

 olate, short-awned; perigynia ovoid, 3 mm. wide. Sandy or rocky soil: N.S. — 

 Me.— Minn. — Sask. Boreal. My-Au. 



146. C. laeviconica Dewey. Culms 6-12 dm. high, very rough above; 

 leaf -blades 3-6 mm. wide, glabrous; sheaths puberulent towards the top, breaking 

 and becoming filamentose; staminate spikes 2-6, distant; pistillate spikes 2-4, 

 densely flowered, except at the base, 2. .5-10 cm. long, 10-16 mm. wide; perigynia 

 ovoid, glabrous, 8-10 mm. long, 3-4 mm. wide. Marshes: 111. — ^Man. — 'Mo. — 

 Kans. — -Mont.^ — Sask. Plain. My-Jl. 



147. C. atherodes Spreng. Culms stout, 6-15 dm. high, often roughish 

 above; leaf-blades 5-12 mm. wide, often pubescent beneath, as are the sheaths; 

 staminate spikes 2-6, distant; pistillate spikes 3-5, densely flowered except at 

 the base, 3-10 cm. long, 12-16 mm. wide; perigynia 8-12 mm. long. C. aristala 

 R. Br. Marshes: N.Y. — Mo.— Colo. — Utah — Ore. — Yukon. Plain — Submont. 

 Je-S. 



148. C. Sheldonii Mackenzie. Strongly stoloniferous; culms very smooth 

 below the spikes, 6-9 (hii. high, neither bright-colored nor fibrillose at the base; 

 leaves about four, the blades 5-6 mm. wide, 2-4 dm. long (or longer on sterile 

 shoots), sparingly short-pubescent, as are the sheaths, the latter dark-tinged at 

 the mouth, the basal breaking and shghtly filamentose; staminate spikes 2-3, 

 distant; pistillate spikes usually 2, widely separate, sessile or short-pcdimcled, 

 oblong-cylindric, 2-5 cm. long, 8-10 mm. wide, rather closely 25-60-flowered ; 

 perigynia 5-6 mm. long, short-pubescent, the beak bidentate, the teeth less than 

 1 mm. long; scales ovate-lanceolate, acuminate or cuspidate. Swamps: Calif. 

 — Ore. — Ida. 



43. ExTENSAE Fries*. Culms slender, but strict, obtusely triangular, leafy 

 towards the base. Leaves septate-nodulose, the blades narrow. S]jikes 2-10, 

 normally the terminal staminate, the others pistillate, suborbicular to oblong, 

 densely flowered, 3 cm. or less long, the upper sessile and approximate, the 

 lower remote, peduncled, erect. Bracts leafy, more or less sheathing. Pis- 



