2 

 SEDGE FAMILY ' 207 



Perigynia or leaves or both pubescent; stigmas 3 31. Hirtae. 



Neither perigynia nor leaves pubescent. 



Style jointeil with the achene, deciduous. 

 Achenes triangular; stignias 3. 



Lowest bract sheatliless ; perigynia not bidentate. 



Pistillate spikes narrowly cylindrie, elongated 26. Anomalae. 



Pistillate spikes ovoid, oblong or linear 27. Atratae. 



Lowest bract sheathing; perigynia bidentate 32. Extensae. 



Achenes lenticular; stigmas 2. 



Achenes not constricted in the middle 28. Acutae. 



Achenes constricted in the middle ; scales sharp-pointed, three-nerved. 



29. Cryptocarpae. 

 Style persistent, continuous mtli the achene. 



Perigynia nerveless, except for the marginal nerves; stigmas 3 



30. Tsachtchlaenae. 

 Perigj'nia several to many-nerved. 



Perigynia coarsely ribbed; stigmas 3 or 2 33. Physocarpae. 



Perigynia finely and closely ribbed ; stigmas 3 



34. PSEUDO-CYPEREAE. 



1. Inflatae. 



Pistillate scales 1-nerved; perigynia ovoid, inflated, tapering at apex; staminate part of spike 

 scarcely conspicuous; aclienes 1.2.5 to 1.5 mm. long 1. C. engelmanii. 



Pistillat* scales 3-nerved ; perigynia broadly ovoid, strongly inflated, abruptly minutely-beaked ; 

 staminate part of spike conspicuous; achenes 2 mm. long _ 2. C. hreweri. 



2. Athrochlaenae. 

 Represented by one species in our range 3. C. nigricans. 



3. Capitatae. 



Represented by one species 4. C. caiiitata. 



4. Foetidae. 



Represented by one species in our range 5. C. vernacula. 



5. Divisae. 

 Rootstocks, slender, light-brownish; cuhns obtusely triangular, normally smooth; leaf -blades 



narrow, involute 6. C. douglasii. 



Rootstocks stout; culms acutely triangular, normally rough above. 



Perigynia chestnut, thick, the beak about one-fifth as long as the body 7. C. simuJata. 



Perigynia blackish in age, the beak one-third to one-half as long as the body. 



Scales very dark chestnut-brown, shining; perigynia 3.5 to 4u5 mm. long, polished, 



scarcely hyaline at orifice 8. C. patisa. 



Scales lighter colored, dull; perigj'nia 3 to 4 mm. long, dull, strongly hyaline at orifice. 



9. C. praegradlis. 

 6. Muhlenbergianae. 



Densely cespitose; head orbicular or oblong-ovoid 10. C. Iwodii. 



Rootstocks elongate; head linear, interrupted 11. C. tumulicola. 



7. Multiflorae. 



Scales strongly hyaline-mai-gined ; sheaths normally not cross-rugulose. 



Perigynia lanceolate-ovate, sharp-margined to base, membranaceous, straw-colored 



12. C. stenoptera. 

 Perigynia ovate, truncate at base, short-beaked, sharp-margined above, not membranaceous, 



bro«Tiish-black at maturity 13. C. alma. 



Scales not strongly hyaline-margined ; sheaths normally more or less cross-rugulose ; perigynia 

 straw-colored, yellowish or tawny at maturity, sharp-margined to base. 

 Perigynia 3.5 to 4.5 mm. long, the beak much shorter than tlie body; pistillate scales (except 

 lowest) acute or cuspidate. 

 Ligule conspicuous, as long as wide; scales bro^\'nish-tinged; perigynia strongly nerved 



ventrally 14. C. densa. 



Ligule very short; scales reddish-brown-tinged. 



Perigynia flat and nerveless or nearly so ventrally, the body sparingly serrulate 



above, contracted into a beak.. 15. C. vicaria. 



Perigynia low-convex and strongly nerved ventrally, the body strongly serrulate 



above, abruptly contracted into a beak 16. C. breviligulata. 



Perigynia 2.25 to 3.25 mm. long, the beak about length of the body; pistillate scales 

 strongly awned 17. C. dudleyi. 



8. Fanlculatae. 



Leaf -blades 1.25 mm. wide; head little Interrupted; perigynia 2 to 2.75 mm. long, shining, not 

 concealed by tlie scales 18. C. diandra. 



