226 CAEDUACEAE 



Leaves not spinulose: corolla-tube dilated above. 



15. ISOCOMA. 



Achenes elongate-obovoid, i. e., tapering at both ends, 

 but more so below, multi-strlate, glabrous or slightly 

 hairy; bracts of the Involucres broad and abruptly 

 acuminate: appendages of the style-branches ovate to 

 short-subulate. 20. Oonopsis. 



Heads radiate. 



Rays scarcely longer than the disk-flower. 18. Pyebocoma. 

 Rays conspicuous, much exceeding the disk. 



Leaves pinnate or toothed; lobes or teeth spinulose-tipped. 

 Pappus of the fertile achenes deciduous in a ring; annuals, 

 equally leafy throughout; bracts more or less foliaceous. 



16. Phionopsis. 

 Pappus persistent. 



Bracts chartaceous, not foliaceous, merely with a green 

 tip ; plants annual, or perennial with a caudex, equally 

 leafy throughout; pappus in age more or less spread- 

 ing; achenes turbinate and densely silky. 



17. SIDEEANTHUS. 

 Bracts more or less foliaceous, at least above; plants 



perennial with taproots, large basal leaves, and few 

 and rather smaU stem-leaves; pappus not spreading; 

 achenes oblong, glabrous or sparingly pubescent. 



18. Pyekocoma. 

 Leaves entire or toothed, but teeth not spinulose-tipped. 



Bracts not longitudinally striate. 



Shrubs with glandular-pimctate leaves. 



Heads large, solitary; involucral bracts in about 2 



series; rays numerous. 19. Stenotopsis. 



Heads small, paniculate or corymbose; bracts well 

 imbricate, in several series; rays few or none. 

 13. Eeicamehia. 

 Herbs or undershrubs ; leaves not glandular-punctate. 

 Bracts abruptly acuminate; stems leafy up to the 



sessile heads. 20. Oonopsis. 



Bracts not abruptly acuminate. 



Style-appendages filiform, much longer than the 

 stigmatic portion; low shrubs with whitish 

 bark and foliaceous outer bracts. 



21. Maceonema. 

 Style-appendages of the stigmas ovate or triangu- 

 lar, not longer than the stigmatic portion. 

 Plants low, cespitose, with a woody caudex. 

 more or less evergreen leaves, and sohtary 

 peduncled heads. 22. Stbnotus. 

 Plants with wholly herbaceous stem, woody, 

 if at all, only at the caudex; leaves not 

 evergreen. 

 Bracts, at least the outer, foliaceous or 

 with foliaceous tips. 

 Disk-flowers tubular ; plants with a tap- 

 root. 18. Pybeocoma. 

 Disk-flowers more or less widened up- 

 wards; plants with rootstocks or 

 short caudices. 

 Heads solitary; rays numerous. 



23. Tonestus. 

 Heads corymbiform-cymose; rays 



small and narrow. 



24. Oeiochhtsum. 

 Bracts not at all foliaceous or merely with 



green tips. 

 Bracts slightly if at all unequal and 

 sUghtly imbricated; heads solitary 

 or few, peduncled. 



45. Eeigebon. 

 Bracts well imbricated and unequal in 

 length. 

 Rays not more numerous than the 

 disk-flowers; receptacle alveo- 

 late. 

 Inflorescence racemose or panicu- 

 late; bracts not in vertical 

 rows. 25. SOLIDAGO. 

 Inflorescence corymblform; bracts 

 in distinct vertical rows. 



26. Petrodoelv. 

 Rays more numerous than the disk- 

 flowers; receptacle flmbriolate; 

 heads corymbose. 



27. EUTHAMIA. 



