242 



CARDUACEAE 



A. Bichardsonii. 

 A. merilus. 



17. A. andinus. 



18. A. Williamsii. 



X. RADULtNI. 



Upper part of the stem and the involucres long-viUous. 

 Upper part of the stem and involucres short-pubescent. 



XI. Andjni. 

 Stems decumbent or ascending, about 1 dm. high; leaves glabrate. 



Stems erect, about 3 dm, high ; leaves finely villous. 



XII. Ghisei. 



Leaves rather copiously and permanently appressed-hirsutulous. 



Inflorescence falsely racemose: lower leaves triple-nerved. 40. A. subracemosus. 

 Inflorescence corymbiform or paniculate; leaves all l-nerved. 



Plant 3-4 dm. high; stem retrorse-hirsute below. 19. A. subgriseus. 



Plant 1-1.5 dm. high; hairs of the stem not retrorse, 20. A. griseolus. 



Leaves sparingly strigose and glabrate in age, or perfectly glabrous, except the hispidu- 

 lous-ciliate margins. 

 Bracts with a green tip and midvein. 



Stem stout ; leaves oblanceolate, the lower often triple-nerved. 



61. A. Underwoodii. 

 Stem slender; leaves narrowly Unear-oblanceolate or linear, l-nerved. 



64. A. Nelsonii. 

 Outer bracts green almost throughout. 21. A. violaceus. 



XIII. MULTIFLORI. 

 Inflorescence very leafy, not corymbiform. 



Pubescence of the stem spreading or reflexed, hirsutulous. 



Heads less than 5 mm. high. 22. A. exiguus. 



Heads 6-8 mm. high. 23. A. crassulus. 



Pubescence of the stem appressed or ascending. 



Bracts very unlike in length, well imbricate, the outer much shorter; heads race- 

 mosely arranged, each at the end of a short leafy branch (except in no. 23) . 

 Bracts narrowly oblanceolate, the inner especially acutish; heads less than 5 

 mm. high. 

 Stem much branched ; heads racemosely disposed on the more or less diverg- 

 ing branches. 24. A. muUiflorus. 

 Stem simple below; heads few at the ends of the erect branches. 



25. A. striclicauUs. 

 Bracts broadly oblanceolate or the outer spatulate, very obtuse; heads over 

 5 mm. high. 26. .4. polycephalus. 



Bracts almost equal in length or the outer sometimes longer; heads few or solitary 

 at the ends of the main branches. 

 Bracts thick, very squarrose, the outer spatulate, rounded at the apex; leaves 



thick, densely strigose. 27. A. commuiatus. 



Bracts thin, slightly squarrose, oblanceolate, acute; leaves sparingly strigose, 

 in age often glabrate. 

 Inflorescence less leafy, corymbiform; leaves glabrous, 

 mm. wide; stem slender. 

 Stem glabrous. 29. A. denudatus. 



Stem puberulent. 67. A. Hallii. 



XIV. Saqittipolii. 



Basal leaf-blades cordate or broadly ovate; upper stem-leaves lanceolate; aohenes gla- 

 brous. 

 Petioles, midribs, and usually also the stem pubescent with long white hairs. 



30. A. Wilsonii. 

 Plant glabrous or sparingly short-pubescent. 31. A. Lindleyanus. 



Basal leaf-blades lanceolate; upper stem-leaves narrowly lanceolate or those of the inflor- 

 escence lance-linear. 

 Heads few; involucres 8-9 mm. high; rays about 15 mm. long; achenes glabrous. 



32. A. MacCallae. 

 Heads numerous; involucres 5-6 mm. high; rays 8-10 mm. long; achenes hlspidulous- 

 strigose. 33. A. Buileri. 



XV. Laeves. 

 Bracts much shorter than the disk. 34. A. brevibracteatus. 



Bracts about equalling the disk or only slightly shorter. 

 Leaves merely scabrous-ciliate. 



Green tips of the bracts broadly rhombic; leaves of the branches much reduced. 



35. A. laeeis. 



Green tips of the bracts narrowly rhombic or rhombic-oblanceolate; leaves of 

 the branches gradually but not conspicuously reduced. 

 Stem-leaves lanceolate or linear-lanceolate, auricled-clasping. 



36. A. Geyeri. 

 Stem-leaves narrowly hnear, not auricled. 37. A. subsalignus. 



Leaves decidedly long-ciliate; bracts with oblong green tips. 38. A. Scribneri. 



XVI. PORTEEIANI. 



One species. 39. A. Porteri. 



XVII. Salicifolii. 



Inflorescence falsely racemose; leaves linear to oblanceolate; leaves triple-nerved. 



40. A. subracemosus. 



28. A. falcatus. 

 merely hispid-ciliolate ; disk 6-8 



