160 LXX. COMPOSITA. 
Tripe 2, Eupatortacem. (Gen. 7-10.) 
Leaves alternate. Pappus of 3-5 unequal scales . 7. ANISOCHETA. 
Leaves opposite. 
Heads many-flowered. 
Pappus of 5-10 broad, toothed, pointed scales 8. AGERATUM. 
Pappus of 3-5 gland-tipped bristles. . . . 9. ADENOSTEMMA. 
Heads 4-flowered. iS eee of Fag slender 
bristles . . . . . 10. MrKanta. 
TRIBE 3. ASTEROIDER. week 11-38.) 
1. Heads conspicuously radiate; rays blue, pink 
or white (not yellow). 
Receptacle covered with rigid pales (chaff) . 12. AMELLUS. 
Receptacle without paleze. 
Ray and disk-flowers both with bristle- 
shaped pappus. 
Pappus-bristles plumose (feathered) . . 13. Marrua. 
Pappus-bristles rough, but not feathered. 
Pappusuniform, of manysimilar bristles 17. ASTER. 
Pappus double, outer bristlesvery short 18. DIPLOPAPPUS. 
Ray-flowers without pappus; disk-flowers 
with bristle-shaped pappus. 
Disk-flowers fertile, with well-feathered 
pappus. . . 16. CHaARIEIS. 
Disk-flowers sterile, ‘with serrated pappus 14, GYMNOSTEPHIUM. 
All the flowers without pappus. Leaves 
pinnatifid. . . . . 21. GaARULEUM. 
2. Heads conspicuously radiate + ; rays ‘yellow. 
Receptacle nude, smooth or minutely rough. 
Pappus well-feathered (plumose). . . . 13. MatrRza. 
Pappus bristle-shaped, rough, in one row. 
Anthers not tailed at base . ... . . 20. NIDORELLA. 
Anthers tailed at base. . . . . . 33. INULA. 
Pappus bristle-shaped, in many rows, 
copious . . . 11. ALCIOPE. 
Pappus double ; outer of short ‘scales, inner 
of, bristles ...00 6 ee ge wpe wot » 34, PURCARE 
Pappusnone . - . 15. ANAGLYPHA, 
Receptacle conspicuously "honeycombed or 
fimbrilliferous. 
Rays neuter, with glabrous, abortive ovaries 36. CYPSELODONTIA. 
Rays female ; ; all the achenes hairy. Pap- 
pus double. 
Pappus of several-toothed win, outer 
shorter. . . 37. MINUROTHAMNUS. 
Pappus of broad scales, all or half of 
themawned . . . 38. GEIGERIA. 
3. Heads heterogamous, either discoid or : very i ried | hh 
perfectly radiate; the margin flower fe- 
male, filiform, or with very short unilabiate 
or bilabiate corollas (imperfect rays). 
Pappus double; outer of short scales, inner 
of bristles . . . 34, PULICARIA. 
Puppus single, of few or many slender bristles. 
Margin-flower imperfectly ligulate (unila- 
biate). 
