136 



10. 

 11. 

 12. 



13. 

 14. 

 15. 



16. 

 17. 

 18. 

 19. 



20. 



21. 



I'lorets all similar 



Outer florets dissimilar, slender or 



rayed ... 

 Florets all ligulate 

 Florets all tubular and hermaphro- 

 dite 

 Leaves alternate ... 

 Leaves opposite ... 

 Heads many-flowered 

 Heads 2-5-flowered 

 Involucre imbricated in 2 or more 



rows 

 Involucre of 10-15 equal bracts in 



one row 

 Pappus plumose ... 

 Pappus setose or scaly ... 

 Leaves and usually involucre 



prickly ... ... ... 41. 



Leaves not prickly ... ... 42. 



Involucre with smaller bracts at 



base ; style branches with long 



points ... 

 Involucre plain ; style branches 



obtuse 39. 



Flowers red ... ... ... 40. 



Flowers yellow ... ... ... 38. 



Flower heads clustered ... ... 2. 



Flower heads in a long spike --. 43. 

 Achenes with long barbed bristles, 



linear ... 

 Achenes with capillary or chafiy 



bristles, short ... 

 Pappus hairs tipped with a gland 

 Pappus hairs not glandular 

 Pappus of chafi'y dilated bristles... 

 Pappus hairs slender 

 Outer florets slender, female, not 



ligulate 

 Outer florets ligulate 

 Keceptacle naked ... 

 Kieceptacle paleaceous 

 Pappus of many hairs 

 Pappus or very short ... 

 Outer female florets few ... 

 Outer female florets very numerous 

 Involucral bracts herbaceous or 



subulate 

 Involucral bracts thin, hyaline ... 

 Stems tall, stiff", with thick 



tomentum ... ... ... 20. 



Stems weak, straggling ... ... 21. 



Anthers obtuse at the base 

 Anthers tailed at the base 



15. 

 5. 



4. 



o. 

 12. 



6. 

 11. 



7. 



9. 



8. 



52. 



Cnieus (p. 149). 

 Saussurea (p. 149). 



10. 



Senecio (p. 148). 

 Emilia (p. 148). 

 Gynura (p. 147). 

 Elephantopus (p. 139). 

 Ainsliaea (p. 149). 



31. Bidens (p. 145). 



13. 



3. Adenostemma (p. 139). 

 14. 



4. Ageratum (p. 139). 



5. Eupatorium (p. 139). 



17. 

 16. 

 40. 

 30. 

 18. 

 25. 

 Inula (p. 144). 

 19. 



22, 



21. 

 20. 



Anaphahs (p. 143). 

 Gnaphalium. (p. 143). 



22. 



24. 



