CARDUACEAE. 331 



stem-leaves ; pappus not spreading ; achenes oblong, glabrous 

 or sparingly pubescent. 12. Pyhrocoma. 



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

 Bracts not longitudinally striate. 



Bracts abruptly acuminate ; stems leafy up to the sessile heads. 



13. OONOPSIS. 



Bracts not abruptly acuminate. 



Appendages of the stigma filiform, much longer than the 

 stigmatic portion; low shrubs with whitish bark and foli- 

 aceous outer bracts. 15. Macronema. 



Appendages of the stigmas ovate or triangular, not longer 

 than the stigmatic portion. 

 Plants low cespitose evergreen undershrubs with more or 

 less evergreen leaves and solitary peduncled heads. 



16. Stenotus. 

 Plants with wholly herbaceous stem, if at all woody only 

 at the caudex ; leaves not evergreen. 

 Bracts, at least the outer, foliaceous or with foliaceous 

 tips. 

 Disk-flowers tubular ; plants with a taproot. 



12. Pyhrocoma. 

 Disk-flowers more or less widened upwards ; plants 

 with rootstock or short caudex. 

 Heads corymbiform-cymose ; rays small and few ; 



plants leafy. 17. Oreochrysum. 



Heads solitary ; rays numerous ; plants dwarf. 



18. TONESTUS. 



Bracts of the inflorescence not at all foliaceous or merely 

 with green tips. 

 Rays not more numerous than the disk-flowers ; re- 

 ceptacle alveolate. 

 Inflorescence racemose or paniculate ; bracts not in 



vertical rows. 19. S01.IDAG0. 



Inflorescence corymbiform ; bracts in distinct ver- 

 tical rows. 20. Petradoria. 

 Rays more numerous than the disk-flowers ; receptacle 

 fimbriolate ; heads corymbose. 



21. Euthamia. 

 Bracts of the involucres longitudinally striate ; heads in con- 

 gested corymbs. 22. Oligoneuron. 

 b. Ray-flowers blue, pink or white. 



1. Pappus a mere crown or of a few scales or awn-like bristles. 



23. TOWNSENDIA. 



2. Pappus of numerous capillary bristles. 



a. Rays only slightly if at all exceeding the pappus ; all annual. 

 Bracts in 2-3 series, the outer foliaceous ; stigma-tips acute. 



24. Brachyactis. 

 Bracts in 1-2 series, narrow, not foliaceous; stigma-tips obtuse. 



32. Leptilon. 

 6. Rays conspicuous, longer than the pappus, usually equalling or ex- 

 ceeding the width of the disk. 

 Stigma-tips lanceolate or oblong to filiform. 

 Perennials with a rootstock or caudex. 



Bracts acuminate, as well as the leaves tipped with callous points 

 or spines ; plants with cespitose caudices and solitary heads 

 at the ends of the stems or branches. 



25. Xylorrhiza. 

 Bracts not acuminate, or if long-attenuate, with soft tips. 



Pappus dilated at the apex ; bracts narrow, more or less keeled. 



26. Unamia. 

 Pappus not dilated at the apex. 



