CAREX KEY. SEDGE FAMILY. 353 



Spike normally solitary. 27. PICTAE. 



Spikes two or more. 



(i) Neither perigynia nor scales blackish. 

 Bracts with obsolete or rudimentary blades. 



Lower spikes nearly radical ; scales abruptly cuspidate. 28. PEDUNCULATAE. 



Lower spikes not radical ; scales not abruptly cuspidate. 



Leaf-blades flat ; perigynia puberulent to pubescent. 29. DIGITATAE. 



Leaf-blades filiform ; perigynia glabrous. 30. ALBAE. 



Bracts with well-developed blades. 



Pistillate spikes short-oblong to linear, erect, or if drooping the spikes short and the 



perigynia acutely triangular ; terminal spike staminate. 



Achenes lenticular; styles two. 31. BICOLORES. 



Achenes triangular ; styles three. 



Perigynia with few to many strong nerves or nerveless. 



Perigynia tapering at base, triangular, closely enveloping the achene. 

 Rootstock long-creeping. 32. PANICEAE. 



Rootstock not long-creeping. 33. LAXIFLORAE. 



Perigynia rounded at base, suborbicular in cross-section, loosely enveloping the 



achene. 34. GRANULARES. 



Perigynia finely many-striate. 



Perigynia tapering at base, constricted at apex, obtusely triangular, closely 



enveloping the achene. 35. OLIGOCARPAE. 



Perigynia rounded at both ends, cross-section suborbicular. 36. GRISEAE. 

 Pistillate spikes elongated, linear to cylindric, slender-peduncled, the lower drooping. 

 Perigynia beakless or short-beaked; terminal spike gynaecandrous. 37. GRACILLIMAE. 

 Perigynia conspicuously or strongly beaked. 



Culms strongly reddish-tinged at base, aphyllopodic. 



Leaves glabrous ; spikes very slender. 38. DEBILES. 



Leaves pubescent ; spikes dense. 39. FLEXILES. 



Culms not strongly reddish-tinged at base, phyllopodic. 



Spikes slender, few-flowered ; perigynia 2" long or less, not inflated, the beak 



not becoming bidentate. 40. CAPILLARES. 



Spikes dense, many-flowered ; perigynia longer, more or less inflated ; the beak 



becoming bidentate. 41. LONGIROSTRES. 



(2) Perigynia and scales strongly blackish. 42. FRIGIDAE. 



Lowest bract sheathless to strongly green-sheathing; if green-sheathing, achenes lenticular and 

 perigynia not dull and subterete, or perigynia with strongly bidentate non-hyaline apex and stiff teeth. 

 Perigynia or foliage (at least the lower sheaths) pubescent ; perigynia beakless, or the beak not 



strongly bidentate ; achenes triangular. 



Terminal spike gynaecandrous. 43- VIRESCENTES. 



Terminal spike staminate. 44. PALLESCENTES. 



= = Perigynia and foliage glabrous, or if pubescent, the perigynia strongly bidentate ; achenes trian- 

 gular or lenticular. 

 Perigynia rough-papillose or granular, beakless ; or if beaked, the orifice not bidentate ; achenes 



triangular. 



Perigynia beakless or very short-beaked. 45. TRACHYCHLAENAE. 



Perigynia conspicuously beaked. 46- ANOMALAE. 



Perigynia glabrous or pubescent, neither papillose nor granular. 

 Perigynia beakless or very short-beaked ; achenes triangular. 

 Terminal spike, if staminate, without rough-awned scales. 



Terminal spike staminate, lateral ones drooping on slender peduncles, at least at maturity. 

 Perigynia glaucous, flattened; spikes not linear-cylindric. 47. LIMOSAE. 



Perigynia not glaucous, not flattened in our species ; spikes narrow. 48. SCITAE. 

 Terminal spike gynaecandrous, or if staminate, the lateral ones strictly erect. 

 Scales dark-tinged. 49. ATRATAE. 



Scales not dark-tinged. 50. SHORTIANAL. 



Terminal spike staminate; scales rough-awned. 51. PALUDOSAE. 



Perigynia with strongly bidentate beak, or if not, the achenes lenticular. 

 Achenes lenticular ; perigynia dull. 



Scales obtuse to acuminate, not long-aristate ; achenes not constricted. 52. RIGIDAE. 

 Scales broad, long-aristate or in some arctic species acute or obtuse ; achenes strongly 



constricted at the middle. 53. CRYPTOCARPAE. 



Achenes triangular, or if (rarely) lenticular, the perigynia not dull. 



Perigynia coriaceous, little if any inflated, often pubescent ; bracts sheathless. 54. HIRTAE. 

 Perigynia membranous or papery, from little to much inflated, never pubescent (rarely 



hispidulous) ; or if slightly coriaceous the lower bract long-sheathing. 

 Perigynia little inflated, abruptly beaked, pistillate scales reddish or chestnut brown; 



lower bract strongly sheathing. 55. FLAVAE. 



Perigynia little to much inflated, pistillate scales not reddish brown or chestnut, or if 



somewhat so, lower bract not strongly sheathing. 



Perigynia lanceolate or lance-subulate, tapering into the beak, many-nerved. 

 Perigynia-teeth reflexed ; perigynia green, early deciduous. 56. COLLINSIAE. 

 Perigynia-teeth not reflexed ; perigynia yellowish-green. 57. FOLLICULATAE. 

 Perigynia broader, abruptly contracted into beak, usually strongly ribbed. 

 Perigynia less than 5" long. 



Perigynium-body ovoid or globose, not truncately contracted. 



Perigynia coarsely ribbed or nerveless. 58. PHYSOCARPAE. 



Perigynia finely and closely ribbed. . 59. PSEUDOCYPEREAE. 



Perigynia with an obovoid or obconic body truncately contracted into the 



prominent beak. 60. SQUARROSAE. 



Perigynia 5" long or longer. 61. LUPULINAE. 



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