CYPERACEAE (SEDGE FAMILY) 



217 



Leaves 0.5-1.5 cm. broad 

 Leaves 1. 5-3. 5 mm. broad 



pp. Teeth of the bc-uk strongly refracted 

 ff. Staminate spikos 2 or more rr. 



176. O.folliculata. 



177. C. mchaua-iana. 



178. C. Miif,n/,it,i. 



Achene distinctly broader than long, Its faces strongly con- 

 caved 171. C. gigantea. 



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

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



bluntly angled above ; leaves prominently nodulose. 

 Perigynla flask-shaped, rather abruptly contracted to the 



beak, 8-6 mm. long. 



Stout ; spikes cyllndric, 2-10 cm. long .... 188. C. rostrata. 

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



long (188) C. rottrata, v. ambigen*. 



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



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



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



harsh ; leaves slightly if at all nodulose //. 

 tt. Beak of the perigynia usually slightly roughened or 



serrulate. 



Pistillate spikes cylindric, 2.5-5 cm. long. 1-1. 5 cm. 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 im. 



MM. Mature perigynia 5-6.5 mm. thick 185. C. Tuckermani. 



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

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



wide. 



Perigynia bladdery inflated. 

 Perigynia ovoid-conic, tapering gradually to the 



beak 182. C. vesicaria. 



Perigynia rounded-ovoid, rather abruptly tapering 



to the beak. 

 Perigynia 6 uim. long. 



Spikes cylindric, 2-7 cm. long . . . (182) C. vesicaria, v. monile. 

 Spikes globose to short-cylindric, 12.5 cm. 



long (182) C. veteicaria, v. dMenta. 



Perigynia 4-5 mm. long .... (182) G. vetricaria, v. Jejuna. 

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

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



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



1. C. muskingum6nsis Schwein. Culms 1 m. 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- 



841. C. scoparia. 



840. C. muskingumensis. 

 Var. MONILIFORMIS 



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)-6.6 mm. 

 long. Low ground or even dry open 

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

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

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

 Var. coNotNSA 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; injl- 



842. 0. scoparia, 

 v. condensa. 



