CYPERACEAE (SEDGE FAMILY) 



211 



148. C. verrucosa. 



78. 

 79. 



C. Halleri. 



C. atrata, v. ovata. 



V» Scales shorter than or about equaling the perig-ynia. 

 Scales rough-awned ; coarse southern plant . 

 Scales blunt; slender northern plants. 

 Spikes sessile, closely approximate in an irregular head 

 Spikes mostly peduncled, spreading or drooping . 

 V. Scales much exceeding the perigj-nia. 



Spikes sessile, erect 



Spikes peduncled, spreading or drooping 

 U. Scales white or greenish, or if verj- brownish the spikes 

 linear-cylindric W. 

 W. Spikes mostly sessile or subsessile and erect X. 

 X. Spikes mostl_v remote ; leaves glabrous, short and broad 



(4-10 mm. broad) 



X. Spikes approximate or overlapping ; leaves long and 

 slender (1-4 mm. broad), at least the sheaths hairy. 

 Perigynia smooth, or when young slightly hair}\ 



Leaves smooth 



Leaves hairv 



Perigynia very hairy. 

 Terminal spike (including the staminate base) l.S-4 



cm. long, one tenth to one seventh as thick 

 Terminal spike 9-13 mm. long, one fifth to one 



third as thick (82) C. Direscens, v 



W. Spikes mostly peduncled, spreading or drooping Y. 



80. C. 'polygamn. 

 111. C. paupercula. 



135. C. granularis. 



(81) 

 81. 



C. triceps, v. Smithii. 

 C. triceps, v. hirsuta. 



82. C. virescens. 



Swanii, 



Y. Perigynia 2 mm. or more thick. 



Scales blunt or cuspidate, much shorter than the 



perigynia 83. 



Scales long-awned, usually equaling the perigynia . 84. 

 Y. Perigynia less than 2 mm. thick Z. 



Z. Bracts with distinct long sheaths ; perigj'nia bluntly 

 angled a. 

 a, Perigynia rounded or narrowed but not definitely 

 stipitate at base Tj. 

 b. Perigj-nia less than 4 mm. long, beakless. 

 Sheaths glabrous ; perigynia obtuse . 

 Sheaths pubescent ; perigynia acutish 

 b. Perigynia 4 umi. or more long. 



Leaves hairy ; perigyrjia beakless 

 Leaves smooth : perigynia beaked. 

 Scales white or whitish : perigvnia with long 

 conic-cylindric beaks .... 



Scales with dark-brown margins ; perigynia 

 with short-conic beaks . . . " . 

 a. Perigynia with slender stipitate bases 

 Z. Bracts sheathless ; perigynia sharply angled 

 T. Perigynia wide-spreading or reflexed. 



Perigynia orbicular to broadly elliptic, compressed, nerve- 

 less, with tiny short point ; bracts erect 

 Perigynia terete, beaked, strong-ribbed ; bracts divergent. 

 Beak about as long as body of iierigynium. 

 Beak much shorter than body of perigynium . 

 Q. Terminal spike staminate throughout c. 



c. Lowest foliaceous bracts of the inflorescence sheathless, or with 

 short colored sheaths or colored auricles, sometimes wanting 

 or reduced to mere colored sheaths d. 

 d. Perigynia pubescent (if rarely glabrous, the spikes mostly 

 crowded at the base of the densely tufted leaves) e. 

 e. Spikes subtended by colored tubular sheaths which are 

 without green blades. 

 Pistillate spikes cylindric, 1—2 cm. long; scales exceeding 



the perigynia 120. 



Pistillate spikes subglobose, 4-7 mm. long; scales much 



shorter than the perigvnia 119. 



e. Spikes bractless or the lowermost with green foliaceous bracts /. 



■ " 101. 



C. formosa. 

 C. Datisii, 



C. Richardsoni. 

 C. conciniia. 

 C. pubescens. 



f. Leaves and culms soft-pubescent 

 f. Leaves and culms glabrous g. 



g. Leaves mostly basal, the culms naked or with short 

 reduced leaves h. 

 h. Scales rough-cuspidate ; perigynia yellowish-brown 

 h. Scales smooth ; perigynia green or whitish i. 



i. Plant strongly stoloniferous, the elongate often leaf- 

 less stolons scaly-bracted and creeping. 

 Beak one fourth to one fifth as long as the body of 



the i)erigynium 



Beak about as long as the body . (100) C. pennsylvanica, v. hicorum 

 i. Plant caespitose or slightly stoloniferous, the basal 

 leafy shoots strongly assurgent j. 

 J. Some (or all) of the culms short and more or leBB 

 hidden by the bases of the leaves k. 



102. C. Cat^ophyllea. 



100. C. pennsylvanica. 



