208 CYPERACEAE 



17. Scirpinae. 



Eepresented by one species in our range 65. C. git/a*. 



18. Montanae. 



Basal spikes not developed , 66. C. inops. 



Basal spikes present. 



Perigynia finely many-ribbed as well as strongly 2 -keeled. 



Scales purplish-tinged, obtuse to cuspidate; body of perigynium globose; staminate 

 spikes many-flowered; basal pistillate spikes on elongated very slender peduncles. 



67. C. globosa, 



Scales reddish-brown tinged, cuspidate or long-awned; body of perigynium oval; stam- 

 inate spikes few-flowered; basal pistillate spikes on short, erect peduncles 



68. C. brainerdii. 

 Perigynia strongly 2-keeled, otherwise nerveless. 



Bract of lowest non-basal pistillate spike leaflet-like, exceeding culms, if at all colored, 

 purplish-broAvn tinged at base. 



Perigynia 2.5 to 3 mm. long, the beak 0.25 to 0.75 mm. long, shallowly bidentate 



69. C. brevipes. 



Perigynia 3 to 4.5 mm. long, the beak 0.75 to 1.50 mm. long, bidentate....70. C. rossii. 



Bract of lowest non-basal pistillate spike squamif orm and shorter than culm or, if longer, 



auriculate and strongly reddish-brown tinged at base 71. C. brevicaulis. 



19. Digitatae. 



Represented by one species in our range 72. C. conoinnoides. 



20. Bicolores. 



Perigynia short-tapering at apex, straw-colored, 2.5 to 3.75 mm. long; achenes strongly apicu- 



late 73. C. salinaeformis. 



Perigynia rounded or truncate at apex, orange-colored or white-pulverulent, smaller; aehenes 



minutely apiculate. 

 Mature perigynia whitish, ellipsoidal, not fleshy or translucent, rather obscurely ribbed; 



scales appressed _ 74. C. hassei. 



Mature perigynia orange or brownish, broader, fleshy or translucent, strongly ribbed; scales 

 divaricate at maturity 75. C. aurea. 



21. Paniceae. 



Perigynia beakless or nearly so; bract sheaths short; plant glaucous; leaf-blades narrow, 



involute 76. C. livida. 



Perigynia strongly beaked; bract sheaths long; plant not glaucous; leaf -blades broad, flat 



77. C. californica. 



22. Laxiflorae. 



Represented by one species in our range 78. C. hendersonii. 



23. Triquetrae. 



Lowest bract sheathless or very short-sheathing; perigynia glabrous, strongly ribbed or nerved. 

 Perigynia ovoid, 3.5 to 4.25 mm. long, abruptly short-beaked, the sides several-nerved. 



79. C. flaccifolia. 

 Perigynia ovoid-lanceolate, 3.75 to 5 mm. long, tapering into the beak, the sides strongly 



ribbed _ 80. C. whitneyi. 



Lowest bract long-sheathing ; perigynia hairy, faintly nerved or nerveless. 

 Leaf -blades hairy; spikes oblong or short-oblong, the upper approximate. 



Perigynia 4 to 5 mm. long, round-tapering at base, finely many-nerved 



81. C. gynodynama. 



Perigynia 3.5 to 4 mm. long, tapering at base, 2-keeled, obscurely striate 



82. C. liirtissima. 

 Leaf -blades not hairy; pistillate spikes linear, widely separate 83. C. triquetra. 



24. Debiles. 



Represented by one species in our range 84. C. mendocinensis. 



25. Frigidae. 



Perigynia triangular or slightly flattened, the beak bidentulate; scales obtusish, the midvein 



not prominent at apex. 

 Spikes widely separate, the staminate one strongly overtopping the uppermost pistillate one ; 



perigynia triangular, 3.5 mm. long or less 85. C. lemmonii. 



Uppermost pistillate spikes bunched, little exceeded by the staminate one; perigynia com- 

 pressed-triangular, longer. 



Pistillate spikes oblong; scales reddish-brown 86. C. luzuUna. 



Pistillate spikes linear-oblong; scales dark-tinged 87. C. ablata. 



Perigynia strongly flattened, the beak bidentate; scales sharp-pointed with midvein prominent 



to apex. 

 Perigynia glabrous; scales smooth; bract sheaths strongly enlarged upward; leaf-blades 



very leathery _ 88. C. luzulaefolia. 



Perigynia sparsely hairy; scales more or less hairy; bract sheaths scarcely enlarged upward : 

 leaf-blades not leathery _ 89. C. fissuricoht. 



