GOMPOSITAE ^COMPOSITE FAMILY) 



477 



Heads radiate (rarely rayless). 



Style branches of perfect flowers flat, or tipped with a distinct 

 appendage; leaves mostly alternate ' . " i '"-i * . ' 

 Style branches of perfect flowers truncate or apipendaged, not 

 . flattened; leaves dften opposite, ' -' '» ''■ - 1 . 



r-^ Tf ! Juvoluore not%carious. 



Pappus naver capillary. 



Receptacle chaffy . . . . . , 



Receptacle not chaffy ' 



Pappus capillary 



Involucre scarious; pappus not capillary , . 

 Anthers caudate at base; style-branches neither truncate nor ap- 

 pendaged;hreada:not radiate. 

 Receptacle not bristly; coroUaa- not udeepl'i^ cleft , . . 

 ReceptaclQlong^l^nstly; corollas deeply cleft .... 



Ill; ASTEREAE. 



V. HELIAKTHEAE, 

 VI. HELENIEAE. 

 VIII. SENECIONEAE. 

 VIL ANTHEMIDEAE. 



IV.' mULEAE. 

 IX. CYNAREAE. 



Series fi. LIGULIFLORAE 



COROLLAS ALL LIGULATE AND PERFECT 



Ligule 5-toothed at the truncate apex 



X. CICHORIEAE. 



Abbreviated Key to the Genera 



: - ' . 'I 



Tribe I. VERNONIEAE 



Only genus 



1. Veraoziia., 



Tribe n. EUPATORIEAE 



Achenira S-angledr '^-^ . .- 



Achenes 8-10-ribbed or -striate. 



Involucral bracts strongly striate-neryed. 



Bracts few . . . .' . . , . 



Bracts numerous .-n • • • • . . 



Involucral bracts faintly nerved, spirally imbricated 



2. Eupatorium. 



3. Kuhnia. 



4. Brickellia.,, 

 6. Liatris. 



' Tribe in. ASTEREAE 



Ray-Sowers yellow, pr wanting. 



Pappi^s of scales ^ : , 



Heads numerous, 4 mm. or less high . . , , ' . 6. Gutierrezia. 



Heads large and showy . , 7. Grindelia, 



Pappus, in part^ at least, of capillary bristles. ' , 



Pappus double, the outer series of small scales , , , 8. Chrvsopsis. 

 Pappus wholly of capillary bristles. 



Rays wanting.^ > ^ 



Involucral bracts in vertical rows . , , . , . 9. Chnrsothamnus. 

 Involucral bracts imbricated but not in distinct vertical 



rows . ' . . . . . . . . 10. Isocoma. 



Rs^s present (sometimes wanting in Nos. 13 and 14), • * . 



Leaves with spinulose-tipped teeth,. • 



Involucral bracts chartacebiis, with green tips . , 11, Sideranthus. 

 Involucral brapts more or less foliaceous . , , , 12. Pyrropoma, 

 Leaves T^ithgut spinul6se-tipped teeth. ' » . 



InvolucraF bracts foliaceous, at least in part, " 



Plant 1 dm. or more high. 



Low- shrubs , , , , ^ . . 14. Macroriema. 



Herbaceous . . , . . ■ , , 18i Oredchrysum, 



Plant only a few cm. high 16, Tonestus, 



Involucral bracts not foliaceous. , 



Head not corymbose. ' * 



Stems leafy. 



Involucral bracts cuspidate . . , .13. Opnopsis. 

 Involucral bracts not cuspidate , , . 19. Splidago. 



Stems scapose, or at least naked above . .15. Stenotus. 



■ '^Heads .corymbose. ... 



Plant^woody at least, at base , ' '. , . J7. , Petradoria. 



Plant herbaceous. ; 



Outer involucral bracts foliaceous . .' . 18. Oreochrysum. 

 ■ Ndiie of the bracts foliaceouB . . . .19, Splidago. 

 Ray-flowers present„not yellow (in No. 27, rarely yellow or want- 

 ing). . , , . 

 Pappu^ a 'Mere ci'own, or of a tew scales or bristles . . 20 Townsendia^ 

 Pappus of numerous capfllary bristles'. 



Rays evident (a few discoid forms in No. 27), 



