CYPERACEAE 57 



b. Perigynia leathery, strongly many-nerved : spikes stouter. 



55. C. oblita. 

 XIX. GRISEAE. 

 Leaves slightly or not at all glaucous. 

 Pistillate spikes dense, usually many-flowered : leaf-blades 4-6 mm. wide, 



soft, spreading. 56. C. grisea. 



Pistillate spikes loosely several-flowered : leaf-blades 2-4 mm. wide, mostly 

 erect, rigid. 57. C. amphibola. 



Leaves, or the whole plant, very glaucous. 58. C. glaucodea. 



XX. GRANULARES. 

 Bracts elongated, mostly overtopping the spikes : perigynia strongly many- 

 nerved. 

 Perigynia 2-3 mm. long. 59. C. granulans. 



Perigynia i-i .5 mm. long. 60. C. Shriveri. 



Bracts short, rarely overtopping the spikes : perigynia finely few-nerved. 



61. C. Crawei. 

 XXI. EXTENSAE. 



Perigynia yellow, 4-6 mm. long, the beak about as long as the body ; leaf -blades 

 over 2 mm. wide. 62. C.flava. 



Perigynia green, 2 mm. long, the beak % as long as the body : leaf -blades less 

 than 2 mm. wide. 63. C. viridula. 



XXII. PALLESCENTES. 



A single species in our range. 64. C. pallescens. 



XXIII. OIvIGOCARPAE. 

 I<eaf-sheaths glabrous. 



Perigynia narrowed at both ends, beakless. 65. C. conoidea. 



Perigynia with short entire beaks. 66. C. oligocarpa. 



Leaf-sheaths pubescent. 67. C. Hilchcockiana. 



XXIV. LAXIPLORAE. 

 A. Plants not at all glaucous, or very slightly so. 

 Beak of the perigynium slender, straight. 68. C. polymorpha. 



Beak of the perigynium bent, short or wanting, 

 a. Leaf-blades mostly narrow, 2-12 mm. wide. 

 Scales, at least the upper ones, obtuse. 

 Bracts elongated : spikes loosely flowered : stems and scapes slender. 



69. C. letanica. 

 Bracts short : spikes densely flowered : stems and scapes stout. 



70. C. Meadii. 

 Scales acute, cuspidate, acuminate orawned. 



Perigynia obtusely .•^-angled. 

 Perigynia obovoid, 2.5-3 mm. long, the beak short, blunt, bent. 



71. C. laxiflora. 

 Perigynia elliptic to oblong, 3-5 mm. long, the beak sharp. 



Perigynia narrowly oblong, 4-5 mm. long, the beak oblique. 



72. C. slyloflexa. 

 Perigynia elliptic, 3-4 mm. long, the beak nearly straight. 



73. C. striatula. 

 Perigynia sharply 3-angled. 



Spikes drooping or spreading : leaf-blades 2-4 mm. wide : perigynia 

 about as broad as long. 74. C. digitalis. 



Spikes erect or nearly so: leaf-blades 6-12 mm. wide : perigynia 

 about twice as long as broad. 75. C. Careyana. 



