216 



CYPERACEAE (SEDGE FAMILY) 



Perigynia obscurely ribbed (158) C. tricJiocarpa, v. Detceyi 



Perigynia prominently ribbed. 



Sheaths hairy (158) C. trichocarpa, v. aristata. 



Slieaths glabrous (158) C. trichocatpa, v. imherbia 



bb. Perigynia thin and papery, usually more or less inflated ^. 



ff. Staminate spike solitary or none or the terminal only partly 

 staniinate (rarely a very short secondary spike at the base 

 of the other) i/'g. 

 gg. Leaves involute-filiform ; perigj'nia broadly conic-ovoid, 5-6 



mm. long 



gg. Leaves flat hh. 



156, G. oligosperma. 



161. 

 162. 

 163. 



0. sgtiarrosa. 

 C. typhinoides. 

 C. Frankii. 



164. 

 165. 



C. Pmudo-Cyperus. 

 C. comosa. 



hh. Perigynia obconic or broadly obovoid, truncate or abruptly 

 rounded above to long subulate beaks ; terminal spike 

 often mostly pistillate. 

 Perigynia longer than the scales. 

 Pistillate scales subulate-tipped or awned 



Pistillate scales blunt 



Perigynia shorter than the rough-awned scales . 

 Jih. Perigynia from subulate to ovoid or globose, if abruptly 

 beaked the terminal spike staniinate ii. 

 ii. Pistillate sjiikes oblong-cylindric or narrower ,jj. 

 jj. Perigynia scarcely inflated, rigid, lance-subulate, slender- 

 stipitate. with prominent rigid crowded ribs, soon 

 retrorse. 

 Teeth of the perigynia nearly parallel .... 

 Teeth of the perigynia strongly divergent . 

 jj. Perigynia inflated, if stipitate large and bladder-like kk. 

 kk. Mature perigynia less than 12 mm. long U. 



U. Pistillate scales mostly with thin serrulate awns ; 



perigjnia not falcate mm. 

 mm, Staminate scales with rough awns ; plants 

 caespitose. 

 Perigynia slightly inflated, narrowly conic ; 



achenes obovoid 



Perigynia with bladdery-inflated subglobose 

 bodies and abrupt beaks ; achenes narrowly 

 ellipsoid-ovoid. 

 Pistillate spikes 1.5-2 cm. thick ; perigynia 7-10 



mm. long 



Pistillate spikes 1-1.3 cm. thick ; perigynia 5-7 



mm. long (167) C. lurida, v. gracilis. 



nvm. Staminate scales smooth, scarcely if at all awned ; 

 plant loosely stoloniferous .... 

 Pistillate scales smooth, or only the lowest 

 serrulate nn. 

 Plant caespitose, forming tussocks ; perigj^nia 

 somewhat falcate. 

 Spikes mostly clustered and sessile at the tip of 

 the culms ; perigynia retrorse. 

 Perigynid s-iO mm. long .... 



Perigvnia 5-(> mm. long . . . (169) C. 

 Spikes scattered, mostly long-peduncled. 



Perigynia wide-s[)reading or retrorse . (169) C reirorsa, v. Hartii. 

 Perigynia ascending . . . (169) C. retrorsa, v. Macounii. 



Plant not caesjiitose, the culms solitary from slen- 

 der rootstocks ; perigynia not falcate 

 Mature perigynia more than I'i mm. long. 

 Achene rhomboid-ovoid, the angles prominently 



nipple-tipped 



Achene narrowly ellipsoid-ovoid, the angles scarcely 

 nipple-tipped. 

 Pistillate sjtikes mostly crowded, sessile or sub- 

 sessile 



Pistillate spikes mostly peduncled, the lowermost 



remote (173) C. lupulina, v. pedunculata. 



Pistillate spikes globose or subglobose oo. 



U. 



nn. 



166. C. hystericina. 



167. C. lurida. 



168. C. Sahweinitsii, 



nn. 



kk. 



169. C. reirorsa. 

 . reirorsa, v. Robinsonii. 



170. C. ITalei. 



172. C. lupuliformis. 



173. C. lupulina. 



ii. 



167. C. lurida. 



oo. Staminate scales prolonged into rough thin awns 

 00. Staminate scales smooth j>p. 

 pp. Teeth of the beak erect or ascending qq. 

 qq. Mature perigynia green. 



Perigynia elongate-rhomboid, cuneate at base. 

 Perigynia glabrous ..... 



Perigynia hispidulous 



Perigynia ovoid to narrowly conic, rounded 

 base. 

 Perigynia ovoid-conic, half as broad as long 

 Perigynia lanoe-conic, one fourth to one third 



as broad as long . . . (175) C. iiitumescens, v. Fenialdii. 



qq. Mature perigynia straw-colored. 



(174) 

 at 



174. 

 C. 



C. Grayi. 

 Grnyi, v. hispidula. 



175. C. ivtumescens. 



