372 CYPERACE^E. (SEDGE FAMILY.) 



More or less thick and rounded. 



Heads fulvous 85 



Heads silvery or silvery-tawny 72, 73, 74 



Perigynium ovate, wing-margined 86, 87 



Perigynium ovate, not margined 75, 76, 77 



Perigynium broadly obovate, nearly pointless 22 



Stigmas three. 



Pistillate spikes nodding 25 



Pistillate spikes erect 23, 24 



Intermediate spikes of the silvery or tawny interrupted head staminate, stigmas two. 



Perigynium short and broad, dark-colored 68 



Perigynium ovate or ovate-lanceolate, straw-colored 67, 69 



Perigynium long-lanceolate, silvery-green 72 



Terminal spike or spikes entirely staminate. 

 Stigmas two. 

 Perigynium strongly nerved. 



Plant stout 40 



Plant very slender 45 var. juncella. 



Perigynium nerveless or nearly so. 

 Bracts all leaf-like, 



Scales ciliate at top 41 



Scales not ciliate 42 



Bracts not conspicuously leafy. 

 Spikes rounded or oval 



Staminate spike short-stalked 35, 45 var. 2 



Staminate spike sessile 47, 50 



Spikes oblong or long-cylindrical 



Perigynium ovate, green or brown-purple 43, 44, 45 



Perigynium obovate, yellow or whitish 20 



Stigmas three. 

 Perigynium hairy. 

 Pistillate spikes few-flowered, almost globular, mostly sessile. 



Scales ciliate . 5 



Scales not ciliate. 



Spikes greenish ; culms slender 7, 8 



Spikes greenish or whitish ; culms very short 8, 9 



Spikes colored 6 



Pistillate spikes few-flowered, linear ; plant delicate 12 



Pistillate spikes several to many-flowered, oblong or cylindrical. 



Perigynium conspicuously nerved 32 



Perigynium nerveless or nearly so. 



Plant hairy throughout 13 



Plant smooth 30 



Perigynium smooth. 

 Pistillate spikes pendulous or nodding. 



Beak slender, longer than body of perigynium ; spikes greenish-white . 29 



Body of perigynium as long or longer than beak. 



Spikes small, 6 or less-flowered ; plant delicate 27 



Spikes nearly globular, pendulous, very dark 48 



Spikes very loosely -flowered, long-linear 26 



Spikes thick and long ; perigynium inflated, 



Greenish straw-colored, slender-beaked, conspicuously more than 10-nerved 34 

 Straw-colored or often purplish, 



More or less ascending 36, 37 



Conspicuously squarrose 38, 39 



Spikes all erect, 



Short-oblong or round, densely-flowered, approximate. 

 Beak short, bifid 31 



