KEY TO THE FAMILIES AND GENERA 



105 



EE. Limb of corolla of bisexual fls. 

 regular and deeply 5-divided 



or 2-lipped MUTISIA TRIBE. 



BB. Style with sweeping hairs beginning 

 at or below the point of forking, 

 forming a ring; or style there thick- 

 ened, or at least there different in 

 color: style-branches often co- 

 herent. 

 c. Head with female or neutral ligu- 



late ray-fls ARCTOTIS TRIBE. 



CC. Head of all bisexual fls. or with 

 nonligulate neutral fls. or rarely 



with female ray-fls CYNAHA TRIBE. 



AA. Plants with milky juice: fis. in head 



all ligulate CICHORICM TKIBE. 



///. Regular Key to the Tribes. 

 1. Vernonia Tribe. 



A. Genua anomalous with enlarged palmately 



quasiligulate outer corollas 1. Stokesia. 



AA. Genus normal with tubular 5-lobed corollas, . . 2. Vernonia. 



2. Eupatorium Tribe. 



A. Anthers truncate at apex, not appendaged: 

 achenes 5-angled, secondary ribs not 



prominent 3. Piqueria. 



AA. Anthers appendaged. 



B. Achenes 5-ribbed, no secondary ribs visible. 

 c. Pappus wholly of capillary bristles. 



D. Involucral bracts 4 4. Mikania. 



DD. Involucral bracts more than 4 5. Eupatorium. 



(Incl. Conoclinium.) 



cc. Pappus chaffy, awned, blunt or crown- 

 shaped 6. Ageratum. 



BB. Achenes 10-ribbed (rarely . 7-8-ribbed), 



secondary ribs conspicuous. 

 C. Involucral bracts not herbaceous, striate- 

 nerved, conspicuously so when dry. 



D. Heads few-fld., corymbose 7. Adenostyles. 



DD. Heads always paniculate 8. Brickellia 



CC. Involucral bracts somewhat herbaceous 

 or partly colored, inconspicuously stri- 

 ate if at all. 



D. The outer bracts successively shorter. . . 9. Liatris. 

 DD. The bracts nearly all equal in length. . . . 10. Trilisa. 



3. Inula Tribe. 



A. The fls. containing both stamens and pistil all 

 sterile, only the unisexual fls. fertile; heads 

 monoecious or dioecious. 

 B. Pappus bristles, especially of fertile fla. f 



united at the base in a ring. 

 C. Heads strictly dioecious, corymbose, 

 rarely solitary ; sterile pappus club- 

 shaped 11. Antennaria. 



cc. Heads containing 1 or both sexes, monoe- 

 cious or dioecious, crowded in a small 

 cluster or cyme surrounded by a long 



conspicuous woolly involucre 12. Leontopod- 



BB. Pappus bristles free: involucre rosette-like, [ium. 



very white-papery 13. 4aOjpMH*. 



AA. The fls. containing both stamens and style 



usually fertile. 

 B. Heads with disk-fls. only. 



c. The heads compound; 1-fld. heads aggre- 

 gated in an involucrate cluster, often 



with petaloid appendages 14. Afyrio- 



CC. The heads simple. [cephalus. 



D. Pappus 15. Hum- >:. 



DD. Pappus crown- or cup-shaped 16. Ammohium. 



DDD. Pappus bristly. 



E. Achenes not beaked. 



p. Bristles often plumose at base. ... 17. Helipterum. 

 FF. Bristles smooth, scarious, barked 



or plumose at apex 18. Helichru- 



[sum. 



EE. Achenes beaked 19. Waitzia. 



BB. Heads composed of both ray- and disk-fls. 

 c. Receptacle not chaffy. 



D. Stigmatic lines not confluent at apex. .20. Podol- pit. 



DD. Stigmatic lines fusing at apex 21. Inula. 



cc. Receptacle chaffy or bristly 22. Buphthnl- 



\inum. 



4. Cynara Tribe. 



A. Heads 1-fld., aggregated into larger involu- 

 crate heads 23. Echinops. 



AA. Heads several-fld. 



B. Fr. with basal areole. 



C. The fr. woolly, not margined. 



D. Pappus scales pointed or terminated 



by a simple awn 24. Xeranthe- 



[mum. 



DD. Pappus-scales plumose 25. Carlina. 



cc. The fr. glabrous, marginal at summit. 

 D. Receptacle bristly. 



E. Filaments glabrous: involucre bracts 



hooked 26. Arctium. 



EE. Filaments warty, hairy, or pectinate- 



ciliate. 

 F. The receptacle not fleshy. 



o. Pappus-bristles not plumose.. . .27. Carduus. 



GO. Pappus-bristles plumose 28. Cirsium. 



FF. The receptacle fleshy 29. Cynara. 



DD. Receptacle not bristly 30. Onopordon. 



BB. Fr. with oblique lateral areole. 

 c. Heads not involucrate with Ivs. 



D. Involucral-bracts without appendages. 31. Serratula. 

 DD. Involucral-bracts with dry, scarious or 



thorny appendages 32. Centaurea. 



cc. Heads surrounded by an involucre of 



thorny Ivs. 



D. Pappus simple, of bristles, scales or 0. . . 33. Carthamus. 

 DD. Pappus of 2 unequally long rows of 



bristles 34. Cnicua. 



5. Aster Tribe. 



A. Heads dioecious and composed wholly of disk- 

 fls 35. Bacchari*. 



AA. Heads not dioecious. 

 B. Color of fls. yellow. 



c. Rays absent 36. Bigelutia. 



cc. Rays present. 



D. The pappus composed of long pales, 

 which are sometimes reduced to a 



crown 37. Gutierrezia. 



DD. The pappus not as in D. 

 E. Pappus-bristles few (4-8). 



F. Involucral bracts in 8 series, 



leathery or scarious at apex 38. Grindelia. 



FF. Involucral bracts in 2-3 series, 



scarious at margins 39. Pentachxta. 



EE. Pappus-bristles copious, in 2-8 series, 



sometimes few in ray-fls. 

 F. Bristles of 2 kinds, the inner 

 series capillary, outer very short 



and setulose orsquamellate 40. Chrysopsis, 



FF. Bristles mostly alike. 



G. Rays usually wanting 41. Linosyns. 



GG. Rays present. 



H. The bristles broad at base, 



aristate 42. Xanthisma. 



HH. The bristles capillary. 

 i. Heads usually many-fld. 



j. Achenes many-nerved.. . .43. Aplopappu*. 



jj. Achenes few-nerved 44. Hazardia. 



ii. Heads usually few-fld. 



j. Bristles rudimentary, 



shorter than achene... .45. Brachychxta. 

 jj. Bristles longer than 



achene 46. Solidago. 



BB. Color of ray fls. at least not yellow. 



c. The pappus 0, or forming a more-or-lesa 

 conspicuous ring of short bristles or 

 hairs, uniform in all fls. 



D. Bracts dry or scarious at margin 47. Brachycome, 



DD. Bracts herbaceous 48. BeUis. 



cc. The pappus composed of numerous bris- 

 tles in 1 or more series, uniform in all fls. 

 D. Involucre with outer bracts partly 

 leafy, inner bracts membranous or 



scarious 49. CaUistephus. 



DD. Involucral bracts all nearly alike. 

 E. Bracts in about 2 series. 



F. Achenes usually small 50. Erigeron. 



FF. Achenes larger, longer: pappus 



more copious 51. Vittadinia. 



EE. Bracts usually in several series, 

 sometimes 2 series in Aster and 

 Felicia. 

 F. Plants woody, resinous. 



o. Achenes cylindrical 52. Olearia. 



GO. Achenes compressed 53. Felicia. 



FF. Plant herbaceous. 



a. Involucral bracts coriaceoois . . . .54. Sericocar- 

 GO. Involucral bracts membranous [pus. 



or herbaceous 55. Aster. 



ccc. The pappus anomalous or absent from the 



rays. 



D. Pappus-bristles shortly plumose ; style- 

 branches broad 56. Charieis. 



DD. Pappus-bristles in 1 series, unequal, 

 rigid, thickened or dilated toward 



the base 57. Townsendia. 



DDD. Pappus of the ray composed of very 

 short palese; disk-pappus of copious 



slender bristles in 1-2 series 58. Heteropap- 



DDDD. Pappus-bristles very short, usually [pus. 



accompanied by 2-4 awns not longer 

 than the achene 59. Boltonia. 



