234 CARDUACEAE 



Heads long-pedimcled : peduncles 2-7 cm. long. 9. C. pedunculata. 



Heads short-peduncled. 



Plant finely silverv-canescent, scarcely at all liii.5Ute. 



10. C. mollis. 

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

 hirsute-ciliate towards the base. 

 Most of the leaves sessile. 



Leaves otalanceolate or obovate, obtuse or merely apiculate; disk 



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



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

 broad. 12. C. hirsulissima. 



Most of the leaves distinctly petioled; disk 10-12 mm. broan 



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



13. C. Bakcri. 

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

 olate. 14. C. floribunda. 



Involucre liirsute or both hirsute and resinous-granuliferous. 



Leaves lanceolate, acute or acuminate, ses.sile; plant densely hirsute with long 



white hairs. 15. C. barbala. 



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

 Involucre densely hiisute, scarcely at all resinous-granuliferous. 



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

 Leaves oblanceolate. the lower petioled. , 



Plant 1-2 dm. liigh; heads usually soUtary and sessile. 



17. C. pumila. 

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



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



resinotLs, only the lower petioled. IS. C. Columbiana. 



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

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



Involucre sparingly hirsute, copiously resinous-granuliferous. 



Upper leaves obovate, oval, 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. resinnlcns. 



Leaves scattered, spreading, 1-2 cm. long; involucres S-0 mm. high. 



21. C. fulcrata. 

 Heads peduncled, naked or subtended by small linear leaves. 



Leaves denselv hispid, not conspicuously granuliferou.s. 



22. C. horrida. 

 Leaves conspicuously granidiferous, only sparingly hispidulous. 



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. asprcUa. 



Stem profusely branched. 14. C. ftoribunda. 



Leaves sparingly hairy, conspicuously granuliferoas. 



25. C. hispida. 

 Leaves narrowlv linear-oblanceolate ; heads subsessile. 



26. C. stenophylla. 

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

 Uferous. 2/. C. oregana. 



13. ERICAMERIA Nutt. 



Heads radiate; bracts not in distinct ranks. 

 Leaves linear-fiUform or linear-oblanceolate. 



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



1. E. nana. 

 Leaves hnear-fiUform, mostly 15-20 mm. long, divaricate; flowers ochroleucous. 



2. E. resinosa. 

 Leaves oblong-oblanceolate, short-cuspidate. 3. E. ccrvina. 



Heads discoid: bracts distinctly 5-ranked. 4. E. paniculala. 



14. CHRYSOTHAMNUS Nutt. Rabbit Brush. 



Bracts of the involucre acuminate. 

 Achenas glabrous. 



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



high. 1- C- deprcssus. 



Leaves narrowly linear, slightly tomentulose or glabrous. 



Bracts thick, strongly carinate, glabrous. 3. C. pnlchdlu^. 



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

 Achenes pubescent, usually strigose. 



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



Bracts 2-3 in each vertical row. 



Outer bracts long-acumuiate, produced and more or less foUaceous. 

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



Leaves very narrowly linear, l-nerved. 



Leaves and branches green, or the latter slightly tomentulose 



5. C. attenuatus. 



