THISTLE FAMILY 997 



77. S. Farriae Greenm. Stem 1-3 dm. high, branched near the base: lower 

 leaves with winged petioles; blades ovate to obovate, 1-4 cm. long, rounded at 

 the apex, crenate to subentire; stem-leaves lyrate or irregularly pinnatifid, the 

 upper bract-like; heads about 1 cm. high; involucres campanulate, sparingly 

 tomentose at the base; bracts often reddish tipped; ligules yellow; achenes gla- 

 brous. Mountains: Alta. — Wash. Mont. Je-Jl. 



78. S. nephrophyllus Rydb. Stem 3-5 dm. high, branched above, gla- 

 brous: basal leaves long-petioled; blades of the earliest reniform or orbicular, 

 slighth' wavy or entire, those of the succeeding ones oval, sinuate; lower stem- 

 leaves petioled and l\Tate, the upper sessile and pinnatifid, with obtuse segments 

 and rounded sinuses; heads rayless; involucres campanulate, 7-9 mm. high; 

 bracts linear, glabrous, 5-6 mm. long, greenish yellow or brownish; achenes gla- 

 brous. (?) S. debilis Nutt. Wet ground: Mont. — Colo. — Ida. Jl-Au. 



79. S. idahoensis Rydb. Stem 4-5 dm. high, branched, striate, tinged 

 with purplish; basal leaves obovate, serrate; lower stem-leaves oblanceolate in 

 outline, about 1 dm. long, petioled, the upper ovate or lanceolate in outline, ses- 

 sile and auricled at the base, all bluish green, pinnately divided into oblong or 

 oblique-cuneate incised segments; heads numerous, about 1 cm. high; bracts 

 ver>' narrowly linear, equalling the disk; achenes glabrous. Wet places: Mont. — 

 Ida.— B.C. 'Plain— Submont. Je-Jl. 



80. S. pauciflorus Pursh. Stem glabrous, 3-5 dm. high, slender; basal 

 leaves petioled; blades oval, ovate, or siibcordate, crenate or rarely serrate, 1-3 

 cm. long; stem-leaves lyrate or pinnatifid, the upper reduced; heads about 8 mm. 

 high; involucre campanulate; bracts narrowly linear, acute, usually purple- 

 tinged; achenes glabrous. S. discoideus (Hook.) Button. Lowground: Lab. — Que. 

 —Mich.— Wyo.— Calif.— B.C.— Alaska. Mont.—Subalp. Je-Au. 



81. S. fedifolius Rydb. Stem slender, weak, about 1.5 dm. high; basal 

 leaves 3-5 cm. long, with slender petioles ; blades 1-2 cm. long, rounded-ovate or 

 broadly oval, wav>' or subentire; stem-leaves mostly small, pinnately divided 

 into short oblong segments; heads 2-3, about 6 mm. high; involucres somewhat 

 turbinate; bracts broadly lanceolate, conspicuously membranous-margined; 

 achenes glabrous. High mountains: Colo. Subnlp. 



82. S. subnudus DC. Stem 1-3 dm. high: basal leaves petioled: blades 

 broadly obovate or orbicular, coarsely crenate-dentate ; stem-leaves pinnately 

 lobed, with clasping bases, the uppermost minute; involucre decidedly turbinate, 

 8 mm. high, with narrow linear-acuminate bracts; ligules orange, 7-8 mm. long; 

 achenes glabrous. Senecio aureus subnudus A. Gray. Marshy ground: Mont. — 

 Wyo.— n Calif.— B.C. Mont.—Subalp. Jl-Au. 



83. S. Wardii Greene. Stem 5-15 cm. high, glabrous; basal leaves petioled; 

 blades thick, obovate, 1-2 cm. long, crenate above the middle or entire; stem- 

 leaves much reduced, sessile, crenate; heads several, in a dense head-like cluster; 

 involucres campanulate, 7-8 mm. high; bracts glabrous, linear-lanceolate; ligules 

 few, 4r-5 mm. long; achenes glabrous. High mountains: Utah — Mont. Mont. 



84. S. petrocallis Greene. Stem 2-10 cm. high; basal leaves numerous, 

 petioled; blades rather thick, broadly obovate or orbicular, 1-2 cm. long, some- 

 what tomentose when young; stem-leaves 1-2, the lower similar, with dilated 

 petioles, the upper linear-lanceolate and bract-like; head 1 or 2; involucre turbin- 

 ate-campanulate, 1 cm. high, slightly floccose at the base; bracts linear, often 

 tinged with purple; ligules golden yellow-, 6-8 mm. long; achenes glabrous. S. 

 petraeus Klatt. S. petrophilus Greene. Alpine peaks: Colo. — Utah — Ida. Sub- 

 alp. — Alp. Je-Au. 



85. S. Porteri Greene. Stem scapiform, purplish; basal leaves numerous, 

 petioled; blades subreniform, crenate or crenately lobed, 8-12 mm. long, dark 

 green above, glabrous; heads solitary, 9-12 mm. high; bracts shorter than the 

 disk, 8 mm. long, linear-lanceolate, purple, the inner slightly scarious-margined ; 

 ligules about 8 mm. long, bright yellow; achenes glabrous. S. renifolius Porter, 

 not Schultz-Bip. Alpine peaks: Colo. Alp. 



