214 



CYPERACEAE (SEDGE FAMILY) 



h. 



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. Mvida. 



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 106. 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. 



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. vaginata. 



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

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

 Je. Tall and slender, with linear -cylindric spikes .... 

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



1. Perigynia sharply angled, with plane faces (forms of 0. laxi- 

 flora might be sought here) vn. 

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



purplish 



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 



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 



Perigynia 3.3-4 mm. long . 



Basal leaves 2-5 mm. broad . 



Scales blunt ; lowest bract greatly overtopping the in- 

 florescence 



Perigynia obtusely angled, or plump and scarcely if at all angled 



147. C, venusta, v. minor. 



122. C. Careyana. 



123. C. platyphylla. 



. 124. C. laxiculmis. 



(124) C. laxiculmis, v. copulato. 



125. C. digitalis. 



126. C. ptychocarpa. 



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. 

 T. Perigynia with several ribs on each face s. 



8. Staminate spike prominent, usually projecting 

 above the pistillate ; culms slightly if at all 

 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. gracillima. 

 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. Michauxii. 

 Basal leaves 3-6 mm. wide . . (127) C. Laxiflora, v. styloflexa. 

 t. Uppermost pistillate spikes approximate at the 



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

 8 . 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) O. laxiflora, v. latifolia. 

 r. Perigynia nerveless or with 1-3 nerves on each face 



(127) C. laxiflora, v. leptonervia 



