145. Cyperacrae 319 



24. Perigynia obovate-orbicular, slightly wrinkled, about 

 equalling the reddish-brown acute or obtuse 

 glumes; leaves 4-9 nun wide; plants cespitose, 

 growing in moist woods, thickets, and roadside 

 ditches, common C. shortiana Dewey 



6. Beak of the perigynium curved, or if straight 0.7-1 nun long; 

 glumes mucronate or aristate, or sometimes merely acutish. 

 25. Beak oblique or abruptly curved, 0.3-0.5 mm long. 



26. Staminate spikes sessile or nearly so; woods, common 



C. blanda Dewey 



26. Staminate spikes long-peduncled. 



27. Stems reddish-tinged at base; woods, not uncom- 

 mon C. gracilescens Steud. 



27. Stems green or brown at base; rich woods, 

 rare; Panther's Den, Union Co., R. R. Mac- 



Mahon in 1959 C. striatula Michx. 



25. Beak straight, 0.7-1 mm long; perigynia 40-50-nerved. 

 28. Sheaths pubescent; perigynia 4-5 mm long; leaves 3-7 

 mm wide; wooded hillsides, rare; near Peoria, 

 Peoria Co., Brendel, McDonald; Stark Co., V. H. 



Chase C. hitchcockiana Dewey 



28. Sheaths glabrous; perigynia 3-4 mm long; leaves 2-4.5 

 mm wide; dry woods in the northern half of the 

 state C. oligocarpa Schk. 



GROUP VI 



Stigmas three; achenes trigonal; spikes two or more; perigynia 

 glabrous, the beak sharply bidentate. 



1. Staminate spike solitary or none, sometimes bearing some pistil- 

 late flowers. 

 2. Mature perigynia 1-2 cm long. 



3. Pistillate spikes globose, the ellipsoid perigynia widely radiate- 

 spreading; beak of the perigynium 1.5-2.5 mm long; 



swampy woods, rare C. intumescens Rudge 



3. Pistillate spikes ellipsoid to cylindrical, the ovoid-lanceoloid 

 perigynia ascending; beak of the perigynium 5-10 mm long. 

 4. Leaves 3-5 mm wide; perigynia 10-12 mm long, the beak 

 smooth, not serrulate; pistillate spikes subglobose- 

 ellipsoid, 2-3.5 cm long; staminate spike 2-2.5 mm 

 wide; stems solitary or few from elongate rhizomes; 

 achenes longer than wide, the angles not prominently 

 thickened; wet ground in woods, s. 111. [C. halci sensu 



Carey, non Dewey] C. louisianica Bailey 



4. Leaves 5-15 mm wide; perigynia 13-20 mm long; pistillate 

 spikes ellipsoid-cylindrical, 2-8 cm long; staminate spike 

 3-5 mm wide; stems cespitose. 



