SEDGE FAMILY 20? 2 



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



Neither perigynia nor leaves pubescent. 



Style jointed with the achene, deciduous. 

 Achenes triangular; stigmas 3. 



Lowest bract sheathless; perigynia not bidentate. 



Pistillate spikes narrowly cylindric, 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. 



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



29. CRYPTOCARPAE. 

 Style persistent, continuous with the achene. 



Perigynia nerveless, except for the marginal nerves; stigmas 3 



30. TKACHYCHLAENAE. 

 Perigynia several to many-nerved. 



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



Perigynia finely and closely ribbed; stigmas 3 



34. PSETJDO-CYPEREAE. 



1. Inflatae. 



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

 scarcely conspicuous; achenes 1.25 to 1.5 mm. long 1. C. engelmanii. 



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

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



2. Athrochlaenae. 

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



3. Capitatae. 



Represented by one species 4. C. capitata. 



4. Foetidae. 



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



5. Divlsae. 

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



narrow, involute 6. C. douglasii. 



Eootstocks stout; culms acutely triangular, normally rough above. 



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



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 4.5 mm. long, polished, 



scarcely hyaline at orifice .....8. C. pansa. 



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



9. C. praegracttis. 

 6. Muhlenbergianae. 



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



Eootstocks elongate; head linear, interrupted -. 11. C. tumulicola. 



7. Multiflorae. 



Scales strongly hyaline-margined; 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, 



brownish-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 the body; pistillate scales (except 



lowest) acute or cuspidate. 

 Ligule conspicuous, as long "as wide ; scales brownish-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. vioaria. 



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



above, abruptly contracted into a beak 16. C. brevttigidata* 



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

 strongly awned 17. C. dudleyi. 



8. Paniculatae. 



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

 concealed by the scales 18. C. diandra. 



