900 CARDUACEAE 



Heads small; disk 1 cm. or less wide; Ugules white; basal leaves linear-oblanceolate, 



entire. 66. E. asper. 



Heads larger; disk 1-1.5 cm. wide; ligules blue or piu-ple; basal leaves usually more 

 or less toothed, oblanceolate. 67. E. oblanceolatus. 



Pubescence spreading; hairs with pustulate bases; ba.sal leaves narrowly oblanceolate; 

 ligules white or rarely pale rose. 68. E. consobrinus. 



Pubescence long, dense, spreading or reflexed. 69. E. Drummondii. 



XIII. Ramosi. 

 One species. 70. E. ramostts. 



XIV. Bellidiastra. 



One species. 71. E. Bellidiastrum. 



XV. DiVERGENTES. 



Stem simple below; rays usually white. 72. E. Wootoni. 



Stem branched at the base; rays usually purplish. 73. E. divergens. 



XVI. Fl.\geli..\res. 



Leaves and stems appressed-hairy. 74. E. flagellaris. 



Leaves and stem densely short-pubescent with spreading hairs. 



Basal leaves oblanceolate, entire, or 3-lobed at the apex; leaves of the stolons linear; 



plant gray. 75. E. covimixlus. 



Basal leaves obovate-spatulate, entire, or with several lateral lobes or teeth; leaves 

 of the stolons oblanceolate; plant greener. 76. E. nudiflorus. 



XVII. Cani. 

 Disk of the heads fuUy 1 cm. high and about 1.5 cm. wide; basal leaves spatulate, obtuse. 



Leaves canescent. 77. E. Wyomingia. 



Leaves silvery white. 78. E. argentatus. 



Disk of the heads 7-8 mm. high and about 1 cm. wide; basal leaves oblanceolate, mostly 



acutish. 79. E. canus. 



XVIII. Caespitosi. 

 Stem leafy; stem-leaves almost as broad as the basal ones. 



Lower leaves narrowly hnear-oblanceolate ; upper leaves narrowly linear; all acute 



and coarsely hairy; rays usually lilac or purpUsh. 80. E. corymbosus. 



Lower leaves oblanceolate or hnear-spatulate, usually obtusisli; stem-leaves Uuear 

 or oblong; aU densely canescent; rays usually wliite. 

 Stem erect, about 3 dm. high, usually with several heads; stem-leaves Unear. 



81. E. subcanescens. 

 Stem decumbent at the base, 1-2 dm. high, with 1-3 (seldom more) heads; stem- 

 leaves oblong. 

 Plant not conspicuously glandular. 82. E. caespilosus. 



Plant conspicuously glandular. 83. E. nauseosus. 



Stem more or less naked above, decumbent at the base; stem-leaves at least the upper 

 ones reduced. 

 Stems about 2 dm. high; disk 10—12 mm. high and about 15 mm. wide. 



84. E. nevadensis. 

 Stems about 1 dm. liigh; disks about 6 mm. high and less than 1 cm. wide. 



85. E. Eatonii. 



XIX. ASPERUGINEI. 



Leaves with a spreading rough pubescence. 86. E. asperugineus. 



Leaves strictly appressed-cinereous. 



Disk 10-15 mm. wide; leaves flnely and densely hairy; involucral bracts strigose. 



87. E. Tweedyi. 

 Disk 5-10 mm. wide; leaves sparingly and coarsely hairy; involucral bracts hirsute 

 and glandular-puberulent. 88. E. tener. 



XX. Arenarioides. 



One species. 89. E. arenarioides. 



XXI. L.^^tevirentes. 

 Stems 1.5-2 dm. liigh, leafy. 



Ligules blue or purple, scarcely more than 1 mm. wide. 90. E. laetevirens. 



Ligules white, 1.5-2 mm. wide. 91. E. montanensis. 



Stem 3-8 cm. high, scapiform, leafless or few-leaved. 



Pubescence of the stem ap pressed or asceiuling; stems decumbent at the base. 

 Leaves grayish strigose, in age glabrate; bracts liirsuto. 



Bracts Unear, acuminate; Ugules mostly purple, 7-8 mm. long. 



92. E. Scribncri. 

 Bracts lance-Unear, acute; ligules mostly white. 30. E. radicatus. 



Leaves and bracts silvery strigose. 101. E. pulvinatus. 



Pubescence of the stem spreading; stems erect; leaves densely liirsutc; Ugules white. ■ 



93. E. Parryi. 

 XXII. Tetrapleuri. 



Ligules fully 1 cm. long, white; involucres about 1 cm. broad. 94. E. ulahensis. 

 Ligules 5-6 mm. long, sky-blue or pinkish; involucres 6-8 mm. broad. 



95. E. sparsifoUus. 



XXIII. FiLIFOLII. 



Involucres hirsute. 96. E. filifolius. 



Involucres strigose. 97. E. linearis. 



