CYPERACEAE (SEDGE FAMILY) 



13 a Staminate spikes usually i in. or less above the upper 



pistillate spike SALLOW SEDGE. (C. lilrida ) 



b Staminate spikes usually 2 in. or more above the upper 



pistillate spike 14 



14 a Pistillate spikes i, sometimes 2 ; beak of perigynia usu- 



ally rough ; perigynia about % as broad as long 



BUTTON SEDGE. (C. bull&ta.) 



b Pistillate spikes 2, sometimes 3 ; beak of perigynia 

 smooth ; perigynia about Vz as broad as long 



TUCKERMAN'S SEDGE. (C. tuckermani.) 



15 a Average leaf less than % in. broad; perigynia much in- 



flated TUSSOCK SEDGE. (C. stricta.) 



b Average leaf % in. or more broad; perigynia little in- 

 flated 1 6 



16 a Perigynia faintly many-nerved; pistillate spikes scattered 



on stem RIVER-BANK SEDGE. (C. riparia.) 



b Perigynia nerveless; pistillate spikes close together 



WATER SEDGE. (C. agudtilis.) 



17 a Plant very hairy throughout. .HAIRY SEDGE. (C. pubescens.) 

 b Plants not hairy throughout 18 



18 a Pistillate spikes less than i in. long 19 



b Pistillate spikes more than i in. long 44 



19 a Pistillate spikes with 3-20 flowers or loosely flowered 



throughout 20 



b Pistillate spikes with 30 or more flowers, rather densely 



flowered 35 



20 a Average leaf more than ^4 in. broad 21 



b Average leaf ^4 in. or less broad 25 



21 a Plants green or yellow, not glaucous 22 



b Plants pale green, glaucous 23 



22 a Leaves Vi-Vz in. broad, yellowish; staminate spike 



very short stalked LONG SEDGE. (C. folliculata.) 



b Leaves Ms-i in. broad, green with purplish sheaths; 

 staminate spike comparatively long stalked and pur- 

 plish PLANTAIN-LEAVED SEDGE. (C. plantaginea.) 



23 a Pistillate spikes on stalks i in. or more long; perigynia 



3-angled SPREADING SEDGE. (C. laxiculmis.) 



b Pistillate spikes not completely as in a 24 



24 a Perigynia hairy, with a 2-toothed beak 



FIBROUS-ROOTED SEDGE. (C. pedicellata.) 

 b Perigynia not hairy, without a beak 



GRAY SEDGE. (C. grisea.) 



25 a Pistillate spikes globose; perigynia spreading, much in- 



flated BLADDER SEDGE; (C. intumescens.) 



b Pistillate spikes not globose; perigynia not spreading.. 26 



26 a Staminate spike with stalk usually i in. or more long. . 27 

 b Staminate spike with stalk M> in. or less long, or wanting 28 



126 



