234 



CYPERACEAE (SEDGE FAMILY} 



434. 0. 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. graclllima Schwein. Tall and slender, sometimes 

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

 mm. ivide), 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. HUMiLis 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 



C. aestivalis 



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

 few-nerved, glandular-dotted, slightly exceed- 

 ing the long-acuminate ichite 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 floicered ; 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 Ont., 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 439. c. stortiana 



