CYPERACEAE (SEDGE FAMILY^ 



207 



e. Perigynia ovate, 8-4 inui. long. 

 Spikes at most 12-ttowered. 



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



proximate ........ 27. C. sMlulata. 



Inflorescence 2-0 cm. long, the 2-4 spikes very re- 

 mote, the terminal with a clavate base 0.5-1 

 cm. long ...... (27) C. stellulata, 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. stellulata, v. excelsior. 



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

 1540-flowered ; perigynia half as broad as . 

 long ....... (27) C. stellulata, v. cephalantha. 



e. Perigynia lanceolate or ovate-lanceolate, 2.5-3 mm. long ; 



inflorescence of 2-0 approximate spikes . . (27) C. stellulata, v. angustata. 

 d. Perigynia more than half as broad 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 1.5-3.5 cm. long ; spikes 15-50-flowered ; 

 coarse plant ........ 28. C. sterilis. 



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



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

 Leaves 1-2 mm. broad ; perigynia faintly nerved or 



nerveless on the inner face. 

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



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

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

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

 very thin and conspicuously nerved, with short smooth 

 beak ; spikes remote ....... 30. C. seorsa. 



B. PKIUGYNIA NOT TIIIX-WINGED, ASCENDING FROM THE FIRST, PLANO- 



CONVEX /. 

 /. Perig3'nia 4 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 ...... 34. 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 ........... 35. 0. Deweyana. 



f. Perigynia less than 4 mm. long a. 



g. Perigynia with serrulate beaks or margins h. 

 h. Inflo 



orescence elongate, from slender to thickish-cylindric i. 

 Perigynia ovate, broadest at base ; spikes mostly or all 



31. C. arcta. 



approximate in a thick cylindric inflorescence 

 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 1.5 cm. apart ; perigynia 2.3-3 mm. long . 



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



perigynia about 2 mm. long . . . (32) C. canescens, v. subloliacea. 

 Spikes 0-12 mm. long, remote, the lowest 2-4 cm. 



apart ....... (32) C. canescens, v. disjui/cta. 



Plant green, not glaucous ; leaves 1-2.5 mm. broad ; 

 spikes with few looselv spreading dark green or 

 brown distinctly beaked perigynia . . . . 



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

 globose loosely flowered silvery 'spikes; perigynia 

 oblong, beakless, nerved, 3-3.4 mm. long . . . 

 g. 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 3 mm. long. 

 Leaves flat, 1-2 rnm. broad ...... 37. C. trisperma. 



Leaves setaceous, 0.3-0.5 mm. broad . . (37) C. trisperma, v. Billingxii. 

 Spikes continuous in a linear-cylindric loose inflores- 

 cence, bractless or only short-bracted ; perigynia 

 2-3 mm. long ........ 32. C. canescens. 



Inflorescence subglobose, of 2-4 closely approximate sub- 

 globose loosely flowered spikes ; perigynia beakless, 

 3 mm. or more long ...... 36. C. tenuiflora. 



j. Spikes ferruginous or dark brown ; terminal spikes with 

 conspicuous clavate base ; perigynia abruptly beaked ; 



32. C. canescens. 



33. C. brunnescens. 



36. C. tenuiflora. 



culms smooth (or harsh only at tips). 



