1264 



CARDUACEAE 



Bracts of the involucre with long slender spreading or recurved tips. 

 Leaves very numerous, often over 100 on the stem, scattered. 

 Stem smooth and glabrous. 



Leaves linear-filiform : bracts of the involucre scarcely ciliolate. 8. H. filiformis. 

 Leaves narrowly linear : bracts of the involucre manifestly ciliate. 9. H. orgyalis. 

 Stem copiously pubescent near the base. 10. H. polyphyllus. 



Leaves few, opposite or merely alternate on the upper part of the stem. 

 Stem not scape-like, evenly leafy to the top : bracts of the invo- 

 lucre barely if at all ciliolate. 11. H. angusti/olius. 

 Stem scape-like, with several elongated leaves near the base and few 



much smaller ones above : bracts of the involucre ciliate. 12. H. elongatus. 



Bracts of the involucre obtuse or acute, or slightly acuminate. , 



Leaves evenly disposed along the stem. 



Stem smooth and glaucous. 13. H. ciliaris. 



Stem scabrous, hirsute or hispid. 



Inner bracts of the involucre acuminate, less than 10 mm. long : 



upper leaves alternate. 14. H. undulatus. 



Inner bracts of the involucre acute, over 10 mm. long: upper 



leaves opposite. 15. H. scaberrimus. 



Leaves mostly near the base of the stem, few above. 

 Ray-flowers with conspicuous ligules. 



Stem and leaves glabrous. 16. H. carnosus. 



Stem and leaves pubescent. 



Bracts of the involucre acuminate : upper cauline leaves nar- 

 row. 17. H. heterophyllus. 

 Bracts of the involucre obtuse or mucronate : upper cauline 



leaves broad. 18. H. atrorubens. 



Ray-flowers with ligules scarcely surpassing the bracts of the invo- 

 lucre, or obsolete. 19. H. Radula. 

 Disk of the head yellow. 



Stem more or less scape-like : leaves mainly near the base of the stem. 



Leaf-blades very scabrous : bracts of the involucre ciliate. 20, H. occidentals. 



Leaf-blades smooth : bracts of the involucre ciliolate. 21. H. Dowellianus. 



Stem not scape-like : leaves evenly disposed along the stem. 



A. Leaf-blades petioled, with petiole-like bases, or if sessile, narrowed 



at the base. 

 Main stem smooth and glabrous. 



Peduncles smooth and glabrous, except sometimes just under the 



involucre. 



Bracts of the involucre ciliate : blades of the upper cauline 

 leaves toothed. 



Leaf-blades glaucous beneath : inner bracts of the invo- 

 lucre 13-14 mm. long, over 4 mm. broad at the base. 22. H. Eggertii. 

 Leaf-bla'des green beneath : inner bracts of the involucre 



9-11 mm. long, less than 3 mm. broad at the base. 23. H. laevigatus. 



Bracts of the involucre eciliate : blades of the upper cauline 



leaves entire. 24. //. longifolius. 



Peduncles pubescent. 



Bracts of the involucre uniformly ciliolate or ciliate. 

 Leaves merely opposite ; blades of a lanceolate type. 



Leaf-blades membranous : stems green or purple : inner 



bracts of the involucre acute. 25. H. microcephalus. 



Leaf-blades thicker : stems glaucous : inner bracts of the 



involucre acuminate. 26. H. glaucus. 



Leaves mainly whorled ; blades of a linear-lanceolate type. 27. H. verticittatus. 

 Bracts of the involucre conspicuously more copiously ciliate 



below the middle. 

 Bracts of the involucre much longer than the height of the 



disk : upper surface of the leaf-blades quite smooth. 



Leaf-blades leathery : corolla-tube about 1 mm. long. 28. H. grosse-serratus. 

 Leaf-blades membranous: corolla-tube about 0.5 mm. 



long. 29. H. decapetalus. 



Bracts of the involucre about equalling the top of the disk. 

 Leaf-blades glabrous or essentially so beneath, quite 



smooth above. 30. H. saxicola. 



Leaf-blades manifestly pubescent beneath, very scabrous 



above. 

 Leaf-blades scarcely paler beneath than above : inner 



bracts of the involucre dilated about the middle. 31. H. australis. 

 Leaf-blades pale beneath : inner bracts of the invo- 

 lucre scarcely dilated, rather abruptly contracted 

 below the middle. 32. H. strumosus. 



Main stem copiously or markedly pubescent. 

 Leaf-blades canescent or tomentose beneath. 

 Disk of the head less than 1.5 cm. wide. 



Leaf-blades attenuate : leaves alternate on the upper part 



of the stem or branches, 33. H. Schweinilzii. 



Leaf-blades acute : leaves opposite. 34. H. cinereus. 



Disk of the head over 2 cm. wide. 35. H. tomentosus. 



Leaf-blades hirsute, hispid or hispidulous, at least about the mid- 

 rib beneath. 

 Leaf-blades prevailingly ovate or lanceolate-ovate. 



Stem hirsute or scabrous : leaf-blades narrowed into petiole- 

 like bases. 36. H. tuberosus. 

 Stem softly pubescent : leaf-blades sessile. 37. H. doroconoides. 

 Leaf-blades prevailingly lanceolate. 



a. Leaf-blades as scabrous beneath as above. 38. H. Maximilianii. 



