CYPERACEAE (SEDGE FAMILY^ 207 



t. Perigynia ovate, 3-4 mm. long 1 . 

 Spikes at most 12-flowered. 

 Inflorescence 1-3 cm. long, the 2-6 spikes subap- 



proximate 27. C. sttllulata. 



Inflorescence 2-6 cm. long, the 2-4 spikes very re- 

 mote, the terminal with a clavate base 0.5-1 



cm. long (27) C. slellttlata, v. ormantha. 



Spikes with more flowers. 



Leaves 1-2.5 mm. broad; spikes scattered, 12-20- 

 flowered ; perigynia less than half as broad as 



long (27) C. stfllulata, v. esece/xior. 



Leaves 2-4 mm. broad ; spikes mostly approximate, 

 15-40-flowered ; perigynia half as broad as 



long (27) C. gtellulata, v. ctphalatitha . 



e. Perigynia lanceolate or ovate-lanceolate, 2.5-8 mm. long ; 



Inflorescence of 2-6 approximate spikes . (27) C. utellvlata, v. anguxtata. 

 d. Perigynia more than half as oroad as long (narrower only 

 in var. of no. 29), firm, brownish or dark green; 

 beak one fourth to one half as long as the body. 

 Scales sharp-pointed ; leaves 2.5-4.5 mm. broad ; inflo- 

 rescence 1.5-8.5 cm. long ; spikes 15-50-flowered ; 



coarse plant 28. t 1 . sterilit. 



Scales blunt; leaves narrower; inflorescence 1-2 cm. 



long ; spikes 5-15-flowered ; slender plants. 

 Leaves 12 mm. broad ; perigynia faintly nerved or 



nerveless on the inner face. 



Perigynia deltoid-ovate, spreading .... 29. C. ncirpoides. 

 Perigynia lance-subulate, ascending . . (29) C. scirpoides, v. Josselynii. 

 Leaves narrower ; perigynia strongly nerved (29) C. scirpoides, v. capillacea. 

 3. Perigynia broadest near the middle, less than 2 mm. broad, 

 very thin and conspicuously nerved, with short smooth 



beak ; spikes remote 80. 0. seoma. 



B. PERIGYNIA NOT THIN-WINGED, ASCENDING FROM THE FIRST, PLANO- 

 CONVEX /. 

 /. J'erigynia4 mm. or more long, long-beaked. 



Spikes lance-cylindric, in a loose linear-cylindric inflorescence ; 

 perigynia 1-1.3 mm. broad, strongly nerved; scales ob- 

 long; leaves 1-2.5 mm. broad 84. C.bromoides. 



Spikes ovoid or ovoid-cylindric ; perigynia 1.6-1.9 mm. broad, 

 faintly nerved or nerveless ; scales ovate ; leaves 2-5 mm. 



broad 85. C. Deweyana. 



f. Perigynia less than 4mm. long g. 



g. Perigynia with serrulate beaks or margins h. 

 A. Inflorescence elongate, from slender to thickish-cyllndric i. 

 i. Perigynia ovate, broadest at base ; spikes mostly or all 



approximate in a thick cylindric inflorescence . . 81. C. arcta. 

 i. Perigynia broadest near the middle. 



Plant glaucous ; leaves 2-4 mm. broad ; spikes with 

 many appressed-ascendiug glaucous obscurely 

 beaked perigynia. 

 Spikes 6-10 mm. long, approximate or the lowest 



rarely 1.6 cm. apart ; perigynia 2.3-8 mm. long . 82. C. canes&sns. 

 Spikes 4-7 mm. long, subapproximate or remote ; 



perigynia about 2 mm. long . . . (82) C. conencfnn, v. subloliacea . 

 Spikes 6-'l2 mm. long, remote, the lowest 24 cm. 



apart (82) C. canescens, v. diujtmctu. 



Plant green, not glaucous ; leaves 12.5 mm. broad ; 

 spikes with few loosely spreading dark green or 



brown distinctly beaked perigynia . . . . 88. C. brunneseen*. 

 A. Inflorescence subglobose, of 2-4 closely approximate sub- 

 globose loosely flowered silvery spikes ; perigynia 

 oblong, beakless, nerved, 3-3.4 mm. long . . .86. C. tenu^flora. 

 Q. Perigynia smooth throughout j. 



j. Spikes whitish, silvery green or pale brown. 



Inflorescence elongate, at least the lower spikes scattered. 

 Uppermost spikes divaricate-pedunculate, lowermost 

 subtended by a leaf-like bract ; perigynia usually 

 more than 8 mm. long. 



Leaves flat, 1-2 mm. broad 87. C. trlnpenna. 



Leaves setaceous, 0.30.5 mm. broad . . (87) G. triperma, v. Billingxii 

 Spikes continuous in a linear-cylindric loose Inflores- 

 cence, bractless or only short-bracted ; perigynia 



2-8 mm. long 82. C. canescens. 



Inflorescence subglobose, of 2-4 closely approximate sub- 



flobose loosely flowered spikes ; perigynia beakless, 

 mm. or more long 86. C. tenniflora. 



j. Spikes ferruginous or dark brown ; terminal spikes with 

 conspicuous clavate base ; perigynia abruptly beaked ; 

 culms smooth (or harsh only at tips). 



