898 CARDUACEAE 



III. COMPOSITI. 



Leaves divided into linear or spatulate divisions ; plant with a cespitose caudex. 

 Leaves pinnately divided. 



Heads radiate; leaf segments rather distant; peduncles 5-20 cm. long. 



15. E. pinnatisectus. 

 Heads discoid; leaf segments crowded; peduncles 2-5 cm. long. 



16. E. mancus. 

 Leaves once to thrice ternately divided. 



Leaf-blades twice or thrice tcrnate. 17. E. compositus. 



Leaf-blades cuneate, ternately or pedate-quinnately cleft at the apex; divisions 

 spatulate. 

 Disk 10-15 mm. broad; bracts linear-subulate, scarcely scarious-margined ; 



lobes of the leaves spatulate. 18. E. trifidus. 



Disk 7-10 mm. broad; bracts linear-lanceolate, scarious-margined; lobes of 

 tlie leaves linear. 19. E. pcdatus. 



Leaves flabeUiform, lobed or twice 3-cleft at the apex; plant with a creeping rootstock. 



20. E. flabelUfolius. 

 IV. Radicati. 

 Head radiate. 



Involucre glandular-puberulent or glabrate, not hirsute. 



Stem and leaves glabrous or nearly so; involucres less than 12 mm. broad. 

 Basal leaves linear-oblanceolate. 21. E. leiomerus. 



Basal leaves spatulate. 22. E. spatfmlif alius. 



Stem and leaves pubescent; involucres 12-15 mm. wide. 



Stem and leaves hirsute. 6.3. E. viscidus. 



Stem strigose; leaves puberulent, especially on the margins. 



2.3. E. controversus. 

 Involucre more or less hirsute or strigose, in some also slightly glandular-puberulent. 

 Leaves and stem glandular scabrous as well as hirsute. 24. E. glandulosus. 

 Leaves and stem hii'sute or strigose, rarely glandular. 



Stem 1 dm. or more high, appressed-pubescent; disk over 1 dm. high; branches 

 of the caudex or rootstock rather slender, often purplish. 

 Leaves narrowly linear-oblanceolate, 1-3 mm. wide, strigose. 

 Involucral bracts with appressed pubescence; rays purple. 



25. E. gracilis. 

 Involucral bracts with spreading pubescence. 26. E. Engelmannii. 

 Rays white; bracts narrowly linear. 

 Rays usually purplish; bracts lance-linear. 

 Leaves oblanceolate to linear-oblanceolate, 3-8 mm. wide, glabrous above, 

 except the margins. 27. E. ursinus. 



Stem 4-7 cm. high; disk less than 1 cm. wide; caudex and its branches stout 

 and short, not purplish. 

 Leaves linear-oblanceolate to spatulate. 

 Stem with appressed hairs, or glabrate. 



Leaves and stem glabrous or nearly so; stem almost leafless. 



28. E. Evennannii. 

 Leaves and stem distinctly strigose, the latter with several leaves. 



29. E. Peasei. 

 Stem with more or less spreading hairs. 



Stems decumbent or ascending ; leaves spreading, either softly hairy 

 or glabrate in age. 

 Pappus double; inner pappus of 10-12 bristles, 2 mm. long; 

 outer pappus of small squamellae; rays white. 



30. E. radicntus. 

 Pappus simple or nearly so, consisting of many bristles, 3 mm. 



long; ravs purple. 3i. JE. rotcnsis. 



Stems and leaves almost erect; the lattor coarsely hirsute. 



Basal leaves narrowly Imear-oblanceolate ; stem-leaves linear. 



32. E. nanus. 



Bas-ii 1- ■ xaa.irowly spatulate; stem-leaves oblanceolate. 



,. „,., 38. E. condensatus. 



H^n^c ^ic^^-H ? '^'^^ hnear-fi iform. , 33. e. ncmalophyllus. 



Heads discoid; leaves narrowly Imear. 34. e. Bloomeri. 



V. PUMILI, 



Pubescence of rather long hau-s; branches of the stem almost erect. 

 Heads radiate. 



Stems over 1 dm. iiigh, when well developed, with more than one head each. 

 Ray-flowers wlute. 



Outer pappus of small inconspicuous bristles ; plant copiously hairy. 

 „ . , . , 35- E. pumilus. 



Outer pappus of broad squamellae; plant sparingly hau-y. 

 ■r>„ „ , , ,. , 36. E. Brandegci. 



Kay-flowers blue or purplish; outer pappus conspicuous and squamellate. 



c!f„™„ „ 11 1 ...1, , , , . , , 37. E. concinnus. 



Stems usuaUy less than 1 dm. high and usually monocephalous 



Leaves spatulate. 38. E. condensatus. 



J-i.eaves narrowly knear-oblanceolate. 32. E nanus 



Heads discoid. 39 e aphan'actis 



Pubescence very short; branches of the stems spreading. 72.' E Woolonii ' 



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