234. CARDUACEAE 



Heads long-peduncled ; peduncles 2-7 cm. long. 9. C. pedunculata. 



Head's short-peduncled. 



Plant finely silvery-canescent, scarcely at all hirsute. 



10. C. mollis. 

 Plant usually grayish-green, conspicuously hirsute on the stem; leaves 

 hlrsute-ciliate towards the base. 

 Most of the leaves sessile. 



Leaves oblanceolate or obovate, obtuse or merely apiculate; disk 



of the heads 15-20 mm. broad. 11. C. villosa. 



Leaves narrowly oblanceolate, decidedly acute; disk 10-12 mm. 

 broad. 12. C. hirsutissima. 



Most of the leaves distinctly petioled; disk 10—12 mm. broaa. 



Involucre more than 1 cm. high and broad ; leaves oblanceolate. 



13. C. Bakeri. 

 Involucre scarcely 1 cm. high and broad; leaves linear-oblance- 

 olate. 14. C. floribunda. 



Involucre hirsute or both hirsute and resinous-granuUferous. 



Leaves lanceolate, acute or acuminate, sessile; plant densely hirsute with long 



white hairs. 15. C. barbata. 



Leaves oblanceolate, oblong, obovate or oval; plant not conspicuously long-hairy. 

 Involucre densely hiisute, scarcely at aU resinous-granuliferous. 



Leaves short, 1-2 cm. long, obovate, nearly all sessile. 16. C. Butleri. 

 Leaves oblanceolate, the lower petioled. 



Plant 1-2 dm. high; heads usually solitary and sessile. 



17. C. pumila. 

 Plant 2-3 dm. high; heads peduncled and corymbose. 



Disk of the heads 8-10 nun. broad; leaves densely hirsute, not 

 resinous, only the lower petioled. 18. C. Columbiana. 



Disk of the heads 12-18 mm. wide; leaves distinctly resinous-granu- 

 Uferous, nearly all petioled. 19. C. grandis. 

 Involucre sparingly hirsute, copiously resinous-granuliferous. 



Upper leaves obovate, ovil, only rarely oblong or broadly oblanceolate, 

 sessile. 

 Heads sessile, subtended by oblong or obovate leaves. 



Leaves numerous, ascending, 3-5 cm. long; involucre about 1 cm. 



high. 20. C. resinolms. 



Leaves scattered, spreading, 1-2 cm. long; involucres 8-9 mm. high. 



21. C. fulcrata. 

 Heads peduncled, naked or subtended by small linear leaves. 



Leaves densely hispid, not conspicuously granuliferous. 



22. C. horrida. 

 Leaves conspicuously granuliferous, only sparingly hlspidulous. 



23. C. viscida. 

 Upper leaves as well as the lower oblanceolate, most of them petioled. 



Leaves broadly oblanceolate; heads peduncled. 

 Leaves decidedly hairy, sparingly granuUferous. 



Stem simple to near the top. 24. C. asprella. 



Stem profusely branched. 14. C. floribunda. 



Leaves sparingly hairy, conspicuously granuliferous. 



25. C. hispida. 

 Leaves narrowly Unear-oblanceolate; heads subsessile. 



26. C. stenophylla. 

 Heads discoid; leaves lanceolate, hispid-ciliate, otherwise glabrous, minutely granu- 

 liferous. 27. C. oregana. 



13. ERICAMERIA Nutt. 



Heads radiate; bracts not in distinct ranks. 

 Leaves linear-filiform or linear-oblanceolate. 



Leaves lineaj'-oblanceolate, rarely 15 mm. long, curved; flowers yellow. 



Leaves Unear-flliform, mostly 15-20 mm. long, divaricate; flowers ochroleucous. 



u. ... , a. 1, ^ -J . 2. jE. rexinostt. 



Leaves oblong-oblanceolate, short-cuspidate. 3. £,", cervina 



Heads discoid; bracts distinctly 5-ranked. 4. E. paniculata. 



14. CHRYSOTHAMNUS Nutt. Rabbit Brush. 



Bracts of the involucre acuminate. 

 Achenes glabrous. 



Leaves oblanceolate or spatulate, scabroiis-puberulent; plant less than 2 dm. 



high. ... 1- C. depressus. 



Leaves narrowly linear, shghtlj tomentulose or glabrous. 



Bracts thick, strongly carinate, glabrous. 3. c. pulchellus 



Bracts thin, not strongly carinate, arachnoid-ciliate. 2. C. Bigelovii 

 Achenes pubescent, usually strigose. . 



Bracts 4-6 in each vertical row. 3. c. pulchellus 



Bracts 2-3 ia each vertical row. 



Outer bracts long-acuminate, produced and more or less foliaceous 

 Leaves linear, more or less distinctly 3-nerved. 4. C. Parryi. 



Leaves very narrowly linear, 1-nerved. 



Leaves and branches green, or the latter slightly tomentulose. 



5. C. attenuatus. 



