CYPERACEAE (SEDGE FAMILY) 



213 



Spikes all sessile and approximate ; perigynia obovoid, 

 prominently ribbed, retuse, with a distinct short 

 entire beak 



Lowest spike peduncled ; perigynia narrowly obovoid, 

 faintly nerved or nerveless, narrowed to the beakless 



tip 

 dist 



q. Perigynia distinctly beaked w. 

 w. Spikes sessile, or the lowermost short-pediceled, erect or 

 oblique ; the bracts very long and much exceeding the 

 inflorescence, rarely 5 mm. broad. 



Leaves involute 



Leaves flat. 



109. G. abbreviate. 



110 (7. pallescens. 



137. C. extensa. 



Beak about equaling body of perigynium .... 

 Beak much shorter than body of perigynium . 

 w. Spikes mostly long-pediceled, spreading or drooping, if ses- 

 sile and erect the bracts more than 5 mm. wide . 

 x. Leaves broad (usually 5 mm. or more); scales strong- 

 ribbed ; spikes dense, the perigynia firm, dull, wide- 



138. 



139. C. Oederi. 



Leaves soft, ribbon -like, dark green ; lower bract 5-10 



mm. wide, much exceeding the inflorescence 

 y. Leaves firm, glaucous ; lower bract 1-4 mm. wide, about 



equaling the inflorescence. 



Perigynia spreading-ascending, glaucous, faintly-nerved 



or nerveless, gradually tapering to the short beak . 



Perigynia squarrose, deep green or brownish, strongly 



many-ribbed, abruptly beaked 



05. Leaves narrow (usually less than 5 mm. wide) ; scales thin, 

 nerveless or slightly nerved ; spikes loosely flowered, 

 the thin lustrous perigynia strongly ascending 0. 

 e. Perigynia abruptly contracted to an awl-shaped beak 



as long as the body 



8. Perigynia gradually contracted to the beak. 



Leaves pubescent; pistillate spikes 5-S mm. thick 



J1S1 



150. C.tcabrata. 



148. C. verrucosa. 



149. C. macrokolea. 



141. C. longirostris. 



148. C. castanea. 

 144. C. capillaris. 



Leaves glabrous ; pistillate spikes 2-4 mm. thick . 

 9. Lowest foliaceous bract of the inflorescence with a prominent closed 



green sheath a. 



a. Perigynia nerveless or with few nerves most prominent toward 

 the base, not uniformly and conspicuously nerved from base 

 to orifice (excepting the marginal nerves) 6. 

 b. Plant caespitose, scarcely stoloniferous, the rootstock short and 



thick ; perigynia with long-attenuate beaks c. 

 c. Perigynia abruptly contracted to a slender beak as long as the 



Perigynia hairy, remote 140. C. assiniboinensis. 



Perigynia smooth, approximate 141. C. longirostris. 



c. Perigynia gradually contracted to the beak d. 

 d. Pistillate spikes oblong-cylindric, densely flowered. 

 Spikes 5-10 mm. thick. 



Leaves glabrous ; scales white 142. <?. cherofceensis. 



Leaves pubescent ; scales brown 148. C. castanea. 



Spikes 2-4 mm. thick. 



Plant 0.5-1.5 dm. high ; spikes approximate . 

 Plant taller ; spikes remote .... 

 d. Pistillate spikes linear-cylindric e. 



e. Basal sheaths reddish-purple or castaneous /. 

 /. Basal leaves 6-10 rnm. broad, scabrous at base 



gynia stipitate, ovoid-trigonous 

 f. Basal leaves 3-7 mm. broad, smooth at base 



gynia fusiform, obscurely trigonous 

 Perigynia glabrous. 



. 144. C. capillari*. 

 (144) C. capillaris, v. elonyata. 



peri- 

 .. 

 peri- 



145. C. arctata. 



Pejrigynia mostly overlapping, 

 i. long, 1 

 white scales 



Perigynia 6-9 mm. long, twice as long as the 



146. C. deMlis. 



Perigynia 4.5-6.5 mm. long; the scales straw- 

 color or greenish-brown. 

 Perigynia twice as long as the scales ; leaves 24 



mm. wide (146) C. dfbilis, v. Rudgei. 



Perigynia one third longer than the scales ; leaves 



4-6 mm. wide (146) <?. deMlis, v. strictwr. 



Perigynia alternate and mostly remote, not over- 

 lapping (146) C. deMlis, v. inlerjecta. 



Perigynia hairy (146) C. deMlis, v. pubera. 



e. Basal sheaths dull pale brown .... (127) C. laxi/lora, v. leptonervia. 

 '. Plant loosely stoloniferous, the elongate rootstock slender; 

 perigynia beakless or with short or abrupt beak g. 



ff. Perigynia hairy 102. C. caryophyllea. 



g Perigynia not hairy h. 

 h. Perigynia beakless or with a very short oblique tip 4. 



