234 



CYPERACEAE (SEDGE FAMILY) 



4o4. <J. formosa. 



435. C. Davisii. 



greenish, inflated, ovoid, puncticulate, obscurely nerved, 

 short-beaked with a slightly notched orifice, all but the 

 lowest one or two twice longer than the blunt or cuspidate 

 whitish scales. Woods and copses, w. 

 N. E. to Ont. and Mich. ; local. May, 

 June. FIG. 434. 



84. C. Davisii Schwein. & Torr. 

 Similar; spikes, 3-7, heavier, 1.5-4.5 cm. 

 long ; perigynia more inflated, strongly 

 nerved and prominently toothed, equaled 

 by the conspicuously awned and spread- 

 ing scales. Meadows and wet woods, 



w. Mass, to s. Minn., and southw. ; rare eastw. and northw. 



May, June. FIG. 435. 



85. C. gracillima Schwein. Tall and slender, sometimes 

 diffuse, 0.3-1 m. high ; leaves broad and flat (the radical 5-9 

 mm. wide}, very dark and bright green ; spikes 3-6, scattered, 



the terminal rarely stami- 

 nate, densely flowered ex- 

 cept at base, peduncled and drooping, or 

 sometimes ascending, 

 green, 2-6 cm. long, 2-3 

 mm. thick ; perigynia ovoid, 



436. C. gracillima. thin and slightly swollen, 



nerved, obtuse, orifice en- 

 tire, twice longer than the very obtuse whitish scale. Wood- 

 lands and meadows, generally common. May-July. FIG. 436. 

 Var. HtiMiLis Bailey is apparently a starved form. Hybridizes 

 with C. triceps, var. hirsuta, C. pubescens, and C. aestivalis. 



86. C. aestivalis M. A. Curtis. Slender but erect, 2.5-6 

 dm. high; leaves very narrow, 1.5-3 mm. wide, flat, shorter 

 than the culm, the sheaths pubescent; spikes 3-5, erect or 

 spreading, 1.5-4.5 cm. long and very loosely flowered, short- 

 stalked ; perigynia ovoid, scarcely pointed and the orifice 



entire, few-nerved, about twice longer than the 

 obtuse or mucronate scale. Rocky woods, 

 mostly on upland slopes, N. H. to Ga., rare. 

 June-Aug. FIG. 437. 



87. C. oxylepis Torr. & Hook. Similar; 

 2-8 dm. high ; leaves 3-7 mm. wide ; perigynia 

 4-5 mm. long, ellipsoid, acute, prominently 

 few-nerved, glandular-dotted, slightly exceed- 

 ing the long-acuminate white scales. Rich 

 woods, S. C. to Mo., and southw. April, May. 

 FIG. 438. 



88. C. Shortiana Dewey. Tall, 3-9 dm. 

 high, in small clumps ; leaves 0.4-1 cm. broad, 

 flat, rough on the nerves ; spikes 3-6, some- 

 what approximate near the top of the culm, 

 the lowest 2 or 3 short-peduncled, erect, 1-3.5 



438. C. oxylepis. cm. long, 4-6 mm. thick, evenly cylindrical, 

 exceedingly densely flowered; perigynia sca- 

 brous, sharp-edged, the orifice entire, squarrose; scales thin 

 and blunt, about the length of the perigynia. Meadows 

 and low woods, Pa. to Out., la., and southw. May, June. 

 FIG. 439. 



89. C. Backii Boott. Forming dense mats ; leaves dark 

 green, 3-5 mm. broad, stiff, very abundant and overtopping 

 the very unequal culms ; spikes solitary, terminating short 

 and long slender culms (0.1-3 dm. long); staminate flowers 



7. C. aestivalis 



439. C. Shortiaim 



