214 CYPERACEAE (SEDGE FAMILY) 



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

 sile or short-stalked, in nearly all the leaf-axils . . 136. C. Orawei, 

 i. Perigynia not granulose ; 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. C.Ucida. 



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

 coming revolute. 



Culms obtusely angled, smooth throughout . . 105. C. panicea. 

 Culms acutely'angled, scabrous at summit. 

 Spikes slender-cylindric, 3.6 mm. thick. 

 Spikes mostly close-flowered, the perigynia over- 

 lapping 1C6. C. tetanica. 



Spikes loosely flowered, most of the perigynia 



. remote (106) C. tetanica, v. Woodii. 



Spikes oblong-cylindric, 6-10 mm. thick . . (106) C. tetanica, v. Meadii. 

 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. nayinata. 



t. 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. mi nor. 

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



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



flora might be sought here) m. 

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



purplish 122. C. Careyana. 



m. 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. platyphylla. 



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 mni. broad. 



Perigynia 2.S-8.2 mm. long 124. C. laaeiculmit. 



Perigynia 3.3-4 mm. long .... (124) C. laaeiculmig, v. copulate. 



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



Scales blunt ; lowest bract greatly overtopping the in- 

 florescence 126. C. ptychocarpa. 



I. Perigynia 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 **. 

 T. Perigynia with several ribs on each face a. 



. Staminate spike prominent, usually projecting 

 above the pistillate ; culms slightly if at afl 

 ancipital t. 

 t. Pistillate spikes distinct, not closely crowded. 



Perigynia plump-obovoid, the short beak ab- 

 ruptly bent to one side. 



Pistillate spikes mostly 1.5-3 cm. long . . 127. C. laxiflora. 

 Pistillate spikes mostly 0.5-1.3 cm. long 



(127) C. laxiflora, v. yracillima. 

 Perigynia ellipsoid-fusiform, the elongate beak 



slightly oblique. 



Perigynia appressed-ascending in an alter- 

 nate-flowered spike . . . (127) C. laxiflora, v. patulifolia. 

 Perigynia oblique or divergent, mostly over- 

 lapping in the densish spike. 



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

 Basal leaves 8-6 mm. wide . . (127) C. laxiflora, v. styloflexa. 

 t. Uppermost pistillate spikes approximate at the 



base of the staminate .... (127) C. laxiflora, v. variant. 

 9 . Staminate spike small and nearly or quite hidden 



among the pistillate ; culms ancipital. 

 Basal leaves elongate, linear-lanceolate, 5-14 mm. 



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



Basal leaves lanceolate, 1.5-4 cm. broad . (127) C. laxiflora, v. latifolia. 

 V, Perigynia nerveless or with 1-3 nerves on each face 



(127) C. laxiflora, v. leptonerria 



