SEDGE FAMILY 209 



26. Anomalae. 

 Represented by one species in our range 90. C. umitUfolia. 



27. Atratae. 



Terminal spLke staminate or sometimes with perijjj'nia in the middle. 

 Basal sheaths not filamentose. 



Culms few-leaved, strongly aphyllopodie 91. C. spectabilis. 



Culms many-leaved, clothed at base with dried-up leaves of previous year 



93. C. raynoldsii. 



Basal sheatlis filamentose _ 93. C. bifida. 



Terminal spike gj-napcandrous ; i.e., the terminal flowers pistillate. 



Culms aphyllopodie, strongly purplish-red at base, the lower sheaths filamentose 



94. C. briabaumii. 

 Culms phyllopodic. 



Spikes 3 to 5, not oblong-cylindric; perigynia walls not papery; perigynia 2.5 to 4.5 mm. 

 long, nerveless or obscurely nerved on face, dull green to brownish-black. 

 Perigynia not papillate-roughened. 



Spikes contiguous, sessile or nearly so, forming a dense head; scales lanceolate, 



strongly exceeding perigynia; cubns stiff, erect 95. C. helleri. 



Lower spike or spikes more or less peduncled, usually distant, erect or nodding; 



scales wider, shorter than or about equaling perigynia ; culms more slender. 



Scales with midvein largely obsolete ; mature perigj-nia 3.5 to 4.5 mm. long, as 



wide or wider on either side than achene, the latter on stipe of nearly its 



own length; sheaths not purplisli-tinged ventrally 96. C. epapillosa. 



Scales with prominent midvein ; mature perigynia 3.5 mm. long, narrower on 

 either side than achene, the latter much longer than its stipe; sheaths 



normally purpli.sh-tinged ventrally 97. C. heteroncura. 



Perigynia papillate-roughened, especially on upper margins 98. C. albo-nigra. 



Spikes 6 to 10, oblong-cylindric; perigynia 5 mm. long, lightly 3-nerved, light green, the 

 walls papery; scales much shorter than perigynia _ 99. C mertensii. 



28. Acutae. 



A. Flowering culms arising prou the center of previous ye.^r's tuft of leave.s and 



SURROUNDED AT BASE Vl'ITH DRlED-UP LEASES OF PREVIOUS YEAR. 



1. Lower sheaths of flowering (ndms not breaTcing and becoming filamentose. 

 Strongly stoloniferous, the ctilms arising one to few together, low; lowest bract normally much 

 shorter than inflorescence; scales with obsolete or slender midvein. 

 Dried first year leaf-blades at base of fertile culms stiff, rigid and conspicuous, concealing 

 the culms ; fertile culm leaves all blade-bearing, the lower sheaths not purplish or his- 



pidulous dorsally 100. C. scopulorum. 



Dried first year leaf -blades at base of fertile culms much desiccated, not stiff, rigid or con- 

 spicuous, and not concealing the culms; lowest fertile culm leaves not blade-bearing, 

 the lower sheaths purplish and more or less strongly hispidulous dorsally 



101. C. gymnoclada. 

 Culms taller, less stiff, in larger clumps; lowest bract equaling or exceeding inflorescence; scales 



with slender midvein or broader light colored center. 

 Perigynia strongly nerved ventrally, the nerves raised. 



Perigynia coriaceous, sessile or nearly so, the beak bidentate; strongly stoloniferous 



102. C. nebrasl-ensis. 

 Perigynia membranaceous, more or less slenderty stipitate, the beak entire; cespitose. 



Perigynia substipitate, orbicular, minutely papillate-roughened; scales deciduous 



103. C. paucicostata. 

 Peryginia strongly stipitate, ovate. 



Perigynia yellowish-green, ribbed, papillate-roughened; scales deciduous 



104. C. hindsii. 

 Perigynia light green or in age glaucous green, nerved, very minutely granular; 



scaler long per.sistent 105. C. keUoggii. 



Perigynia nerveless ventrally or with obscure impressed nerves. 



Sheaths colored ventrally at mouth ; lower pistillate spikes eernuous or subeernuous on 



long peduncles; scales in age whitened at tip _ 106. C sitchensis. 



Sheaths not colored ventrally at mouth; lower pistillate spikes not nodding; scales not 

 whitened at tip 107. C. aquatilis. 



2. Lower or middle sheaths of flowering culms breaking and becoming filamentose. 



Beak of perigynium bidentate, hispidulous between teeth; scales strongly rough-awned 



108. C. barbarae. 



Beak of perigynium entire or emarginate, not hispidulous Ix-tween teeth; scales not rough- 

 awned. 



