THISTLE FAMILY 993 



45. S. plattensis Nutt. Stem 2-5 dm. high, loosely floccose, very tardily 

 glabrate; basal leaves petioled, 3-10 cm. long; blades ovate or elliptic, floccose 

 when young, glabrate in age; lower stem-leaves petioled, lyrate-pinnatifid, with 

 oblong lobes, the upper sessile, reduced, linear-lanceolate in outline, pinnatifid 

 or toothed; heads corymbose; involucres campanulate, 6-7 mm. high, tomentose 

 at the base; bracts lance-linear, acute, the calyculate ones minute, subulate; 

 ligules about 8 mm. long, orange; achenes hispidulous on the angles. S. pseudo- 

 tomentosus Mack. & Bush. Prairies and river valleys: wOnt. Mo. Tex. Colo. 

 Mont. Sask. Plain. My-Je. 



46. S. neomexicanus A. Gray. Stem 2-4 dm. high, densely and loosely 

 floccose when young; basal leaves 3-8 cm. long, petioled; blades spatulate, coarsely 

 dentate, tomentose on both sides, glabrous in age above; stem-leaves very small, 

 linear-oblanceolate or linear, more or less dentate or pinnatifid; heads rather few, 

 corymbose; involucres campanulate, about 8 mm. high, shorter than the disk, 

 tomentose at the base; bracts lance-linear, acute; ligules light yellow, 8 mm. long. 

 Mountains: N.M. Ariz. (? Colo.). Son. My-Jl. 



47. S. Leonard! Rydb. Stem 4-5 dm. high, loosely floccose; lower leaves 

 petioled; blades obovate or oval, 2-6 cm. long, densely crenate, rather thick, 

 loosely floccose, or in age glabrate, rounded at the apex, the middle ones more or 

 less lyrate-pinnatifid at the base, the upper 1-3 cm. long, lanceolate in outline, 

 pinnately lobed and somewhat auriculate-clasping; heads in a rather dense 

 corymb; involucres somewhat turbinate and floccose at the base, 5-6 mm. high, 

 6-7 mm. broad; bracts linear, acute, carinate; ligules orange, about 6 mm. long, 

 2 mm. wide. Valleys: Utah. Jl. 



48. S. salicinus Rydb. Stems several, about 4 dm. high, simple below, striate 

 and floccose; basal leaves 5-10 cm. long, narrowly oblanceolate, the first ones 

 subentire, but most of them serrate except at the tapering base, finely tomentose 

 on both sides, in age more glabrate above; stem-leaves small, linear, sessile, den- 

 tate, slightly auricled at the base; heads subumbellate, 7-8 mm. high, slightly 

 floccose at the base; bracts yellowish, thin, lanceolate, shorter than the disk; 

 ligiiles light yellow, short and broad, 3-4 mm. long; achenes glabrous. Moun- 

 tains: Colo. Submont. Je-Jl. . 



49. S. canovirens Rydb. Stem 4-5 dm. high, loosely floccose; lower leaves 

 5-12 cm. long, short-petioled; blades lanceolate or oblanceolate, sinuately toothed, 

 dark green, firmly floccose, in age almost glabrate above; upper leaves linear, 

 sinuately dentate, with rather acute teeth; cyme with erect or ascending branches; 

 involucre 7-8 mm. high, turbinate-campanulate; bracts 12-14, oblong, linear, 

 floccose at the base and more or less villose; ligules 5-6 mm. long, at first orange, 

 in age paler; achenes glabrous. Mountains: Colo. N. M. Submont. Mont. 

 Je-Au. 



50. S. Fendleri A. Gray. Stem 2-3 dm. high, floccose when young, but in 

 age sometimes almost glabrate, floccose only at the axils of the leaves; leaves all 

 deeply pinnatifid, or the lower oblanceolate, round-lobed or entire, more or less 

 tomentose on both sides or glabrate above, 4-8 cm. long, the lower petioled, the 

 upper sessile; divisions of the leaves toothed or cleft; heads corymbose; invo- 

 lucres campanulate, 4r-5 mm. high, one-half to two-thirds as high as the disk, 

 only slightly tomentose at the base; bracts lance-linear,- abruptly acuminate; 

 ligules yellow, 5 mm. long; achenes glabrous. S. rosulatus Rydb., a form with 

 subentire basal leaves. S. Nelsonii Rydb. Mountains: N.M. Colo. Utah. 

 Submont. Alp. Je-Au. 



51. S. lanatif olius Osterhout. Stems several, 1-2 dm. high, usually branched, 

 very leafy to the inflorescence; leaves linear, pectinate-pinnatifid, the divisions 

 crenate-toothed with inrolled edges, especially those of the lower leaves; both 

 stem and leaves pannose-canescent; heads numerous and crowded, about 8 mm. 

 high; involucres campanulate, glabrate; bracts about 7, the calyculate ones 

 minute; flowers 15; rays none; achenes glabrous. Hills and mountains: Colo. 

 Neb. Plain Mont. 



52. S. uintahensis (A. Nels.) Greenm. Stems several, 2-4 dm. high, floc- 

 cose when young, soon glabrous; leaves pinnatifid or the lower lyrate, tomenfcose 



