THISTLE FAMILY 979 



8. A. puberula Rydb. Stem about 3 dm. high, glandular-puberulent; 

 lower leaves short-petioled; blades ovate, 2-4 cm. long, puberulent and glandular- 

 pruinose, entire or slightly dentate; upper stem-leaves sessile, ovate, mostly 

 entire; heads 1-5; involucres turbinate, about 1 cm. high and broad; bracts ob- 

 lanceolate, glandular-puberulent, with deltoid tips; ligules 10-12 mm. long; 

 achenes glandular-puberulent, brown; pappus straw-colored, barbellate. Rocky 

 places and hillsides: Alta. Wyo. B.C. Mont. Jl-Au. 



9. A. arnoglossa Greene. Stem 3-5 dm. high, rather slender, glandular- 

 puberulent and with scattered hairs; lower leaf -blades lanceolate, acute, wing- 

 petioled, remotely serrate, strongly 5-ribbed, firm, sparsely scabrous, pale beneath; 

 upper stem-leaves lanceolate, sessile; heads 1-5, usually 3; involucres turbinate, 

 9-10 mm. high, glandular-puberulent; achenes slightly hirsute. Hills: (Black 

 Hills) S.D. Wyo. Alta. Submont. Mont. Je-Au. 



10. A. Jonesii Rydb. Stems 3-4 dm. high, glandular-puberulent and 

 slightly villous, especially on the peduncles; basal leaves long-petioled; blades 

 ovate-cordate, 1-3 cm. long, sparingly villous and glandular-puberulent; stem- 

 leaves sessile, ovate-cordate, 2-5 cm. long, dentate; heads 1-3; involucres turbin- 

 ate, 10-12 mm. high and as broad; bracts linear-lanceolate, acuminate, slightly 

 villous, as well as glandular-puberulent; ligules about 1 cm. long; achenes glandu- 

 lar-puberulent and with a few stiff hairs on the upper part; pappus straw-colored, 

 barbellate. Mountains: Utah. Mont. Jl-Au. 



11. A. ventorum Greene. Stem 2-4 dm. high, glabrous or nearly so; basal 

 leaf-blades ovate to orbicular-cordate, thin, repand-denticulate, 3-6 cm. long, 

 delicately ciliolate, otherwise glabrous; stem-leaves 2-3 pairs, the lower short- 

 petioled, the upper sessile, oval or ovate, acute, minutely denticulate; heads 1-3; 

 involucres turbinate, 12-15 mm. high, puberulent; bracts narrowly oblanceolate, 

 acuminate; achenes glandular-scabrellous. Wet places in the mountains: Wyo. 



-Utah. Mont. Au. 



12. A. Menziesii Hook. Stem 3-6 dm. high, sparingly hairy or nearly gla- 

 brous below; basal leaf-blades cordate or broadly ovate, sinuately dentate, 4-8 

 cm. long, minutely puberulent, thin; stem-leaves 2-4 pairs, the lower short- 

 petioled, the rest sessile and usually more sharply toothed; heads 3-5; involucres 

 broadly turbinate, 10-12 mm. high; bracts narrowly oblanceolate, acuminate; 

 rays bright yellow, 12-15 mm. long; achenes sparingly glandular-puberulent, or 

 with a few short hairs towards the apex. A. platyphylla A. Nels., at least in part, 

 more glabrous than the type. Meadows: Calif. Mont. Alaska. Mont. Je-Au. 



13. A. latifolia Bong. Basal leaf -blades 4-6 cm. long, ovate or cordate, 

 toothed, minutely puberulent or glabrate, thin; lower stem-leaves short-petioled 

 and more oval; upper stem-leaves sessile, oval; heads 1-5; involucres turbinate, 

 12-15 mm. high, sparingly villous-pilose; bracts narrowly oblanceolate, acumin- 

 ate; achenes usually wholly glabrous. A. teucrifolia Greene. A. platyphylla 

 Rydb. (Fl. Colo.). A. ventorum Coult. & Nels., in part, not Greene. Wet places: 

 Alta. Colo. Utah Alaska. Je-Au. 



14. A. silvatica Greene. Stem slightly villous, with scattered hairs and 

 somewhat glandular-puberulent above; basal leaf-blades ovate, glabrous or 

 slightly glandolar-puberulent above, hirsutulous-ciliolate on the margins, coarsely 

 dentate; stem-leaves 4-5 pairs, the lower wing-petioled, the uppermost sessile, 

 very coarsely incisely dentate, all more or less connate-sheathing; heads 3-5; 

 involucres hemispheric, 12-15 mm. high; bracts linear-lanceolate, acute; achenes 

 sparsely hirsute. Woods: Colo. Mont. Jl-Au. 



15. A. diversifolia Greene. Stem 3-6 dm. high, densely glandular-puberu- 

 lent and with a few scattered hairs; basal leaf -blades broadly ovate or subcordate, 

 saliently toothed, glandular-puberulent on both sides or nearly glabrate beneath; 

 upper stem-leaves ovate and sessile, saliently toothed; heads 1-5; involucres 

 hemispheric; bracts lanceolate, acuminate; achenes hirsute on the angles. A. 

 latifolia viscid ula A. Gray. Mountains: Alta. Calif. B.C. Mont. Jl-S. 



16. A. longifolia D. C. Eat. Stem tufted, leafy, 3-6 dm. high, finely puberu- 

 lent; leaves linear-lanceolate, 5-15 cm. long, entire or denticulate, finely puberu- 



