The Flora of the Cayuga Lake Basin 113 



PAGE 



/;. Terminal spike partly pistillate (see also no. 88) ; basal sheaths 

 purple. 

 i. Sheaths pubescent ; perigynia acute ; spikes ascending or 



spreading 89. C. aestivalis 130 



*. Sheaths glabrous ; perigynia obtuse ; spikes usually drooping. 



90. C. gracillima 130 

 /. Perigynia widespread or reflexed, especially the beak; bracts divari- 

 cate; basal sheaths brown; (spikes subglobose or oblong, sessile or 

 nearly so). 

 g. Perigynia 2-3 mm. long, greenish, the beak much shorter than the 



body; spikes oblong, 4-8 mm. in diam. .91. C. Oederi, var. pumila 130 

 g. Perigynia 4-6 mm. long, yellow when ripe, the beak equaling the 

 body; spikes subglobose, 8-15 mm. in diam. 

 /;. Perigynia 5-6 mm. long; scales and tips of the perigynia brown; 



leaves 2-5 mm. wide 92. C. flava 130 



h. Perigynia 4 mm. long ; scales and tips of the perigynia pale ; 



leaves 1-3 mm. wide 93. C. cryptolepis 130 



d. Perigynia with orifice rigidly bidentate. 



e. Perigynia pubescent; plant stoloniferous ; (staminate spikes usually 

 more than 1; pistillate spikes scattered). 

 /. Teeth of the perigynia less than 1 mm. long; perigynia broadly 

 ovoid, short-beaked. 



g. Leaves very narrow, involute-filiform 94. C. lasiocarpa 130 



g. Leaves broader, flat, 2-5 mm. wide 95. C. lanuginosa 130 



/. Teeth of the perigynia more than 1 mm. long ; perigynia ovoid or 

 ovoid-lanceolate, the beak nearly as long as the body. 

 g. Plant hairy ; staminate scales hairy ; perigynia ovoid ; culms 



obtusely angled 96. C. hirta 131 



g. Plant not hairy ; staminate scales not hairy ; perigynia lanceolate 



or ovoid-lanceolate; culms acutely angled 97. C. trichocarpa 131 



e. Perigynia not hairy, usually large and inflated; plant stoloniferous or 

 cespitose. 

 /. Staminate spikes 2 or more (in no. 101 only the upper 1 or 2 wholly 

 staminate) ; scales of the pistillate spikes not rough-awned but 

 often very acute. 

 g. Perigynia spindle-shaped, scarcely inflated, firm ; plant stolonif- 

 erous : 98. C. riparia, var. lacustris 131 



g. Perigynia ovoid, inflated and papery. 



h. Leaves 3-5 mm. wide; plant cespitose; culms sharply angled, 

 not spongy-thickened at base; sheaths not nodulose; spikes 

 erect, scattered ; perigynia ascending. 



*. Perigynia 4 mm. thick or less 99. C. vesicaria, var. monile 131 



i. Perigynia 5-6.5 mm. thick 100. C. Tuckermani 131 



h. Leaves 4-10 mm. wide ; plant cespitose ; culms acutely angled, 

 not spongy-thickened ; sheaths scarcely nodulose ; spikes 

 spreading; lower perigynia reflexed (see also 3d h). 



i. Spikes contiguous 101. C. retrorsa 131 



i. Spikes distant, the lower ones peduncled, all more slender. 



101a. C. r., var. Bradleyi 132 

 h. Leaves 4-12 mm. wide; plant stoloniferous; culms scattered, 

 obtusely angled, spongy at base ; sheaths nodulose ; spikes 

 erect, scattered, dense; perigynia spreading but not reflexed, 

 shorter than in the last-mentioned species. 



