CYPERACEAE (SEDGE FAMILY) 



217 



pp. 



inat 



Leaves 0.5-1.5 cm. broad 

 Leaves 1.5-3.5 nun. broad 



Teeth of the beak strongly refracted 



ff. Staminate spikes 2 or more rr. 



176. C.follieulata. 



177. C. Michauxiana. 



178. C. subulata. 



rr. Achene distinctly broader than long, its faces strongly con- 



caved ..." ........ 171. C. gigantea. 



rr. Achene longer than broad, the faces flat or slightly convex ss. 

 ss. Culm thick and spongy at base, generally smooth and 



bluntly angled above ; leaves prominently nodulose. 

 Perigynia flask-shaped, rather abruptly contracted to the 



beak, 3-6 mm. long. 

 Stout ; spikes cylindric, 2-10 cm. long .... 183. C. rostrala. 



Slender ; spikes globose or short-cylindric, 1-2.5 cm. 



long ......... (183) C. rostrata, v. ambig&ns. 



Perigynia tapering gradually to the beak, 0.5-1 cm. 



long ........ (183) C. rostrata, v. utriculata. 



ss. Culm scarcely spongy at base, sharp-angled above, often 



harsh ; leaves slightly if at all nodulose tt, 

 tt. Beak of the perigynia usually slightly roughened or 



serrulate. 



Pistillate spikes cylindric, 2.5-5 cm. long. 1-1. 5cm. thick 184. C. bullata. 

 Pistillate spikes globose to thick-cylindric, 1-4 cm. long, 



1.5-2 cm. thick ....... (184) C. bullata, v. Greenii. 



tt. Beak of perigynia smooth uu. 

 uu. Mature perigynia 5-6.5 mm. thick ..... 



uu. Mature perigynia not more than 4 mm. thick WD. 



w. Perigynia ascending, straight; leaves firm, 2-7 mm. 



wide. 



Perigynia bladdery inflated. 



Perigynia ovoid-conic, tapering gradually to the 

 beak ........ 



Perigynia rounded-ovoid, rather abruptly tapering 



to the beak. 

 Perigynia 6 mm. long. 



Spikes cylindric, 2-7 cm. long . . . (18' 

 Spikes globose to short-cylindric, 1-2.5 cm. 



long . . ..... (182) C. venicaria, v. distenta. 



Perigynia 4-5 mm. long .... (182) C. vezicaria, v. jejuna. 



Perigynia barely inflated, conic-subulate . (182) C. vesicaria, v. Raeana. 

 vv. Perigynia retrorse or wide-spreading, slightly falcate ; 



leaves soft and ribbon-like, 0.5-1 cm. wide . . 169. C. retrorsa. 



185. C. Tuckermani. 



182. C. vesiearia. 



C. vesicaria, v. monile. 



1. C. muskingumensis Schwein. Culms 1 ra. or less 

 high, very leafy ; leaves subcordate at their junction with 

 the loose green sheaths, those of the 

 sterile shoots crowded and almost dis- 

 tichous ; inflorescence oblong, of 5-12 

 appressed-ascending pointed spikes ; 

 perigynia very thin and scale-like, 

 barely distended over the achenes. 

 Meadows, swamps, and wet woods, 

 O. to Man. and Mo. July, Aug. FIG. 

 340. 



2. C. scoparia Schkuhr. Culms 

 0.2-1 m. high, mostly slender and 

 erect ; leaves narrow (at most 3 mm. 

 wide), shorter than the culm ; inflo- 

 rescence of 3-9 straw-colored or brownish mostly shining 

 and ascending approximate ovoid pointed spikes (0.5-1.5 

 cm. long) ; perigynia ^(rarely 4)-6.5 mm. 

 long. Low ground or even dry open 

 soil, rarely in woods, Nfd. to Sask. and 



Ore., and southw. May-Aug. FIG. 341. Var. MQNILIFORMIS 

 Tuckerm. Spikes scattered, the lowest remote. Less common. 

 Var. CONDENSA Fernald. Spikes spreading, crowded in a globose 

 or subglobose head. N. B. to Ont. and Ct. FIG. 342. 



3. C. tribuloides Wahlenb. Culms loose, 0.3-1 m. high, 

 sharply trigonous ; leaves soft and loose, 3-8 mm. broad, numer- 

 ous, the upper often nearly or quite overtopping the culm, those 

 of the sterile shoots crowded and somewhat distichous; inflo- 



341. C. scoparia. 



340. C. muskingumensis. 



342. C. scoparia, 

 v. condensa. 



