284 



CAEDUACEAE. 



Stigmas of the perfect flowers with 



terminal appendages. 

 Stigmas of the perfect flowers with 

 truncate or hairy or papillose 

 tips. 



Bracts of the involucre herbaceous. 

 Bracts of the involucre dry and 



scarious. 



Bracts of the involucre little if at all 

 imbricate, except when the broad outer 

 ones overlap the inner. 

 Receptacle chaffy. 



Bracts of the involucre herbaceous, some- 

 times foliaceous. 



Bracts of the involucre dry and scarious. 

 Anthers with elongate, cartilaginous, mostly con- 

 nate appendages at the tip. 



TRIBE I. VERNONIEAE. 



Tribe III. ASTEREAE. 



Tribe VI. HELENIEAE. 

 Tribe VII. ANTHEMIDEAE. 



Tribe VIII. SENECIONEAE. 



Tribe V. HELIANTHEAE. 

 Tribe VII. ANTHEMIDEAE. 



Tribe IX. CYNAREAE. 



Heads not glomerate and involucrate : pappus double : corollas 



regular. 

 Heads glomerate and involucrate : pappus single : corollas 



irregular. 



TRIBE II. ETJPATORIEAE. 



Achenes 3-5-angled, ribless. 



Erect herbs : involucral bracts more than 4. 



Receptacle flat : corollas white, pink, or purple. 

 Receptacle conic or hemispheric : corollas blue or violet. 

 Climbing vines : involucral bracts 4 or fewer, or rarely 



more. 

 Achenes 8-10-ribbed or 8-10-striate. 



Heads spicate or racemose: corollas pink to purple: bracts 



of the involucre smooth or faintly striate. 

 Heads corymbose : corollas pale : bracts of the involucre 

 striate-nerved. 



TRIBE III. ASTEREAE. 



Heads with perfect, at least not dioecious, flowers : ray-flowers 



usually present. 

 Ray-flowers with yellow corollas, (white in Solidago 



Mcolor). 



Pappus, at least that of the disk-flowers, double, the 

 outer series of scales or short-bristles, the inner 

 of capillary bristles. 

 Pappus wholly of capillary bristles. 



Bracts of the involucre broad, longitudinally ribbed. 

 Bracts of the involucre narrow, not ribbed. 



Receptacle pubescent, fimbrillate : ray-flowers 

 more numerous than those of the disk. 



1. VERNONIA. 



2. ELEPHANTOPDS. 



3. EUPATORIUM. 



4. CONOCLINIUM. 



5. MlKANIA. 



6. LACINIARIA. 



7. KUHNIA. 



0. 



10. 



CHRYSOPSIS. 

 OLIGONEURON. 



EUTHAMIA. 



SOLIDAGO. 



Receptacle alveolate : ray-flowers fewer than 



those of the disk. 11. 



Ray-flowers with white or colored corollas, not yellow. 



Pappus a mere crown, or of 2-4 awns and short 



bristles. 12. BOLTONIA. 



Pappus, at lea,st in the disk, of numerous capillary 



bristles. 



Pappus mainly of a single series of bristles. 

 Bracts of the involucre in 3-many-series. 



Ray with few flowers, the ligules inconspicu- 

 ous : involucre narrow ; bracts thick, firm. 13. SERICOCARPUS. 

 Ray with usually many flowers, the ligules 

 conspicuous : involucre turbinate, hemi- 

 spheric or globose ; bracts thin, herbaceous. 



14. ASTER. 

 Bracts of the involucre in 1 or 2 series. 



Heads conspicuous : ray-flowers several- 

 numerous ; ligules longer than the diam- 

 eter of the disk. 15. ERIGERON. 

 Heads inconspicuous : ray-flowers few ; lig- 

 ules shorter than the diameter of the disk. 16. LEPTILON. 

 Pappus manifestly double, the bristles of the inner 



series longer than those of the outer. 

 Involucre of 2-4 series of bracts : ligules of 

 the ray white or nearly so : achenes broad : 

 leaf -blades several-ribbed. 17. DOELLINGERIA. 



