214 CYPERACEAE (SEDGE FAMILY) 



i. Perigynia granulose-roughened ; spikes very remote, ses- 

 sile or short-stalk<-.l, in nearly all the leaf-axils . . 136. C. Craicei. 

 i. Perigynia not granulo.-e ; spikes (except in rare cases 

 long-stalked basal ones) borne only toward the sum- 

 mit of the culm j. 

 j. Leaves white-glaucous, quickly becoming plicate or 



involute 104. (7. livida. 



J. Leaves green, slightly if at all glaucous, flat, in age be- 

 coming revolute. 



Culms obtusely angled, smooth throughout . . 10ft. C.panicea. 

 Culms acutely angled, scabrous at summit. 

 Spikes slender-cylindric, 3.6mm. thick. 

 Spikes mostly close-flowered, the perigynia over- 

 lapping 106. C. tetaniea. 



Spikes loosely flowered, most of the perigynia 



remote (106) <?. tetaniea, v. Woodii. 



Spikes oblong-cylindric, 6-10 mm. thick . . (106) ('. fet<t>iic<i, v. Meauii. 

 h. Perigynia with a straightish slender beak. 



Culm stiff, harsh above ; spikes stiffly erect, densely many- 

 flowered . 107. C. polymorpha. 



Culm flexuous, smooth throughout ; spikes spreading or 



drooping, loosely few-flowered 108. C. vayinata. 



a. Perigynia with numerous uniform nerves from base to orifice (ex- 

 treme specimens of nos. 106, 107, 108 might be sought here) k. 



k Tall and slender, with linear -cylindric spikes .... 147. C. venusta, v. minor. 

 k Low, or if tall with thick-cylindric to globose spikes I. 



I. Perigynia sharply angled, with plane faces (forms of C. laxi- 



jtora might be sought here) tn. 

 tn. Perigynia 5-7 mm. long ; staminate spikes dark brown or 



purplish 122. C. Careyana. 



tn. Perigynia 2^4 mm. long; staminate spike straw-color or 



pale brown n. 

 n. Basal leaves 1-3 cm. broad ; pistillate spikes sessile and 



erect 123. C. platyphytta. 



n. Basal leaves narrower, or, if rarely 1 cm. broad, the spikes 



flexuous on capillary peduncles. 

 Scales acuminate or aristate ; lowest bract slightly if at 



all overtopping the inflorescence. 

 Basal leaves 6-12 mm. broad. 



Perigynia 2.8-3.2 mm. long 124. C. laaticulmis. 



Perigynia 8.3-4 mm. long . . . . (124) C. laxiculmia, v. copulata. 



Basal leaves 2-5 mm. broad 125. C. digitalis. 



Scales blunt ; lowest bract greatly overtopping the in- 

 florescence 126. C. ptychocarpa. 



I. Perigvnia obtusely angled, or plump and scarcely if at all angled o. 

 o. Perigynia strongly ascending, beakless or with broadly 

 conic oblique tips ; spikes mostly scattered ; bracts 

 strongly ascending p. 



p. Perigynia fusiform to fusiform-obovoid, tapering sub- 

 equally to the conic tip and the long gradually con- 

 tracted base, obtusely trigonous q. 



q. Perigynia bearing distinct elevated ribs ; scales smooth r. 

 r. Perigynia with several ribs on each face . 



8. Staminate spike prominent, usually projecting 

 above the pistillate ; culms slightly if at all 

 ancipital t 

 t. Pistillate spikes distinct, not closely crowded. 



Perigynia plum p-obo void, the short beak ab- 

 ruptly bent to one side. 



Pistillate spikes mostly 1.5-8 cm. long . . 127. C. laxiftorn. 

 Pistillate spikes mostly 0.5-1.8 cm. long 



(127) C. laxiflora, v. gracillima. 

 Perigynia ellipsoid-fusiform, the elongate beak 



siitrhtly oblique. 



I'eriirynia appressed-ascending in an alter- 

 nate-flowered spike. . . (127) r. luxi flora, v. patulifvlia. 

 Perigynia oblique or divergent, mostly over- 

 lapping in the densish spike. 



Basal leaves 7-12 mm. broad . (127) C. laxiflora, v. Micham-ii. 

 Basal l.-avcs :M nun. wide . . (127) C. laxiflora, v. atylofleva. 

 t. Uppermost pistillate spikes approximate at the 



base of the staminate .... (1'27) (\ laxijlora, v. variatix. 

 . Staminate spike small and nearly or quite hidden 



among the pistillate; culms nncipital. 

 I'.asal leaves elongate, linear-lanceolate, .%-14 mm. 



broad (127) C. laxiflora, v. blanda. 



Basal leaves lanceolate, 1JM cm. broad . (127) C. faw^fofW, v. latifolia. 

 i-. Perigynia nerveless or with 1-8 nerves on each face 



(127) C. lttj-{ffur<i, v. /tjtfo/n/ / /./ 



