884 CARDUACEAE 



12. A. Fendleri A. Gray. Stem 1-3 dm. high, stiff, sparsely hispidulous; 

 leaves linear, 1-nerved, 2-3 cm. long; heads few; involucres turbinate, 7-8 mm. 

 high, fully 1 cm. broad; bracts acute, unequal, in 3 or 4 series; ligules violet, 8 mm. 

 long. Plains and sand hills: Kans. Tex. N.M. Colo. Plain Submont. S. 



13. A. alpinus L. Stem pilose throughout; basal leaves numerous, 2-5 cm. 

 long, rounded at the apex, pilose; involucres about 1 cm. high, 2 cm. wide; bracts 

 oblong or linear, obtuse, pilose, in 2 or 3 series, but nearly of the same length; 

 rays fully 1 cm. long, violet. A. culminis A. Nels. Arctic-alpine situations: 

 Mack. Colo. Alaska; Eurasia. Alp. Je-Jl. 



14. A. Jessicae Piper. Stem densely villous, almost tomentose, 4-15 dm. 

 high; leaves obovate to oblanceolate, 5-10 cm. long, densely and softly grayish- 

 pubescent on both sides, sessile; involucre hemispheric, about 15 mm. high and 

 broad; bracts herbaceous, oblong, obtuse or acute, villous-pubescent; ligules 

 numerous, bluish purple, about 1 cm. long. A. latahensis Henders. A. mollis Rydb. 

 River banks: Wyo. Wash. Submont. Mont. Au-S. 



15. A. Richardsonii Spreng. Stem 1-3 dm. high; leaves sparingly short- 

 villous on both sides or glabrate above, 3-10 cm. long; heads few; involucres 

 about 1 cm. high and 1.5 cm. wide; ligules purplish, nearly 1 cm. long. A. mon- 

 tanus Richards. A. giganteus (Hook.) Rydb. Arctic-alpine situations: Mack. 

 Alta. B.C. Alaska. Alp. Jl-Au. 



16. A. meritus A. Nels. Stem ascending, 2-4 dm. high; leaves somewhat 

 crenate-serrate or some entire, glabrous above, puberulent beneath, 3-7 cm. 

 long; inflorescence corymbiform; involucre turbinate-campanulate, 8 mm. high, 

 1 cm. broad; bracts in 3-4 series, acute; ligules purple or violet. Mountains: 

 Mack. S.D. Wyo. B.C. Submont. Subalp. Jl-Au. 



17. A. andinus Nutt. Stem somewhat villous above; lower leaves oblanceo- 

 late or spatulate, 4-6 dm. long, ciliolate on the margins; upper stem-leaves 

 linear, sessile; involucres about 10 mm. broad; bracts linear, acute or the outer 

 obtuse, few, in 3 series, but only slightly unequal. High mountains: Mont. 

 Colo. Mont. Subalp. Je-Au. 



18. A. Williamsii Rydb. Stem erect, about 3 dm. high, more or less villous; 

 leaves oblanceolate, 3-10 cm. long, finely villous on both sides; heads few, corym- 

 bose; involucre about 1 cm. broad; bracts linear or lance-linear, sparingly and 

 finely villous on the back, imbricate in 3 series; ligules lilac, about 1 cm. long. 

 Mountains: Wyo. Mont. Jl-Au. 



19. A. subgriseus Rydb. Stem decumbent or ascending at the base; lower 

 leaves oblanceolate, pale, 7-10 cm. long, the upper oblong or linear, sessile, entire, 

 1-nerved; involucres about 8 mm. high and 1 cm. broad; bracts linear or oblong, 

 the outer obtuse ; the inner acutish; ligules 8 mm. long, pale violet. A. griseus 

 Greene, not Kuntze. Mountains: Wyo. Colo. e Utah. Mont. Jl. 



20. A. griseolus Rydb. Stem 1-1.5 dm. high; leaves linear, 3-5 cm. long, 

 sessile, acute, entire; heads 1-4 in a small corymb; involucres about 1 cm. wide; 

 bracts oblanceolate or linear, the outer obtuse, the inner acute, green or the 

 inner white on the sides below; ligules purple, about 8 mm. long. (?) A. spith- 

 amaeus Greene, not Kuntze. High mountains: Colo. Mont. Subalp. Au. 



21. A. violaceus Greene. Stem 3-4 dm. high, purple-tinged, strigose; lower 

 leaves linear-oblanceolate, 10-12 cm. long, petioled, the upper sessile, linear, 

 entire; inflorescence corymbose; involucres 15 mm. broad; bracts linear, the 

 outer obtuse and wholly herbaceous; ligules violet, 1 cm. long. Dry places in 

 the mountains: Colo. Au-S. ' 



22. A. exiguus (Fern.) Rydb. Stem erect, branched and very leafy above; 

 branches divergent; leaves linear or oblong, sessile, 0.5-3 cm. long, entire, densely 

 hirsutulous; heads very numerous at the ends of short leafy branches; involucres 

 about 4 mm. high and broad; ligules white, 3-4 mm. long. Prairies and plains: 

 Vt. Pa. Tex. Ariz. Wash.; Mex. Plain Submont. Au-O. 



23. A. crassulus Rydb. Stem erect or ascending, branched above, 4-7 dm. 

 high; stem-leaves linear, or oblong-linear, 3-6 cm. long, 2-3 mm. wide, sessile 



