THISTLE FAMILY 869 



VI. Radulae. 

 One species. 23. S. Garretiii. 



VII. INCANAE. 



Plant low, 1-2 dm. high; inflorescence corymbiform; branches not secund. 



Bracts oval to oblong, obtuse. 24. S. nana. 



Bracts lanceolate, acute. 25. S. nivca. 



Plants tall, 2-6 dm. high; inflorescence narrow, or if open with distinctly secund branches. 

 Bracts oblong or linear, obtuse ; stem-leaves scarcely triple-veined ; inflorescence 



usually narrow. 

 Stem-leaves oblanceolate. 26. S, pulcherrima. 



Stem-leaves spatulate or broadly oblanceolate. 27. S. radulina. 



Bracts lanceolate or ovate, acute; stem-leaves distinctly triple- veined ; inflorescence 



usually more open. 

 Stem-leaves oblanceolate or elliptic; bracts lanceolate. 28. *S. trinervala. 



Stem-leaves obovate, thick; bracts ovate. 29. S, mollis. 



One species. 



VIII. Wardtaxae. 



30. 5. Wardii. 



1. S. scopulorum (A. Gray) A. Nels. Stem glabrous below, pilose above; 

 basal leaves 5-15 cm. long; blades oblanceolate or spatulate, usually obtuse, 

 crenate or serrate towards the apex; upper stem-leaves lanceolate or Hnear- 

 lanceolate, sessile; bracts acute, ciliolate; achenes strigose. S. corymbosa Nutt., 

 not Ell. S. multiradia^a scopnlonan A. Gray. Hills and mountains: Alta. — 

 Colo. — Utah — B.C. AIonL Je-Au. 



2. S. ciliosa Greene. Stem 1-2 dm. high, decumbent at the base, glabrous 

 below, pilose above; basal leaves spatulate, serrate-crenate towards the apex, 

 2-5 cm. long, tapering into a short petiole; stem-leaves linear-lanceolate to 

 linear-oblanceolate, entire, sessile, ciliolate; heads in a small dense th>TSUs; 

 achenes strigose. Higher mountains: Alta. — Colo. — Ariz. — B.C. Mont, — Alp. 

 Je-S. 



3. S. rubra Rydb. Stem about 3 dm. high, pubescent, reddish; basal and 

 lower cauline leaves 6-12 cm. long, firm, bluish green, glabrous, serrulate and 

 minutely scabrous on the margins; upper stem-leaves sessile and lanceolate; 

 bracts narrowly linear-lanceolate, ciliolate; achenes strigose. Mountains: Colo. 

 MonL S. 



4. S. laevicaulis Rydb. Stem rather tall, 4-7 dm. high, light-colored and 

 shining; basal leaves rather thin, obtuse, 5-10 cm. long, entire or crenate, glabrous 

 except the scabrous margin; upper stem-leaves narrowly lanceolate, sessile; 

 branches nearly erect; bracts narrowly linear-lanceolate, acute, ciliolate on the 

 margins; achenes sparingly strigose. Mountains: Colo. — Wyo. Jl-S. 



5. S. decumbens Greene. Stem low, decumbent at the base, glabrous or 

 nearly so; basal leaves spatulate or oblanceolate, obtuse or rounded at the apex, 

 crenate-serrate towards the end; upper leaves narrower; bracts linear or oblong; 

 heads 6-8 mm. high; achenes strigose-hirsute. A. humilis nana A. Gray. Higher 

 mountains: Wyo.— N.M. Suhalp.—Alp, Jl-S. 



6. S. oreophila Rydb. Stem glabrous or nearly so, often tinged with red; 

 lower leaves spatulate, rounded and serrate or crenate at the apex, 3-10 cm. 

 long, glabrous; stem-leaves oblanceolate, entire or nearly so; panicle narrow; 

 heads about 8 mm. high; bracts linear; achenes hirsute-strigose. S. hiuniHs A. 

 Gray in part, not Nutt. Mountains: B.C. — Mack. — Colo. Mont. — Subalp. 



Jl-S.' 



7. S. dilatata A. Nels. Stem glabrous, 4-6 dm. high; basal leaves gla- 

 brous, scabrous-ciliolate, oblong-spatulate to elliptic, 1-1.5 dm. long, serrate; 

 stem-leaves lanceolate, the upper sessile; heads numerous, in a rather open pan- 

 icle, 6-8 mm. high; bracts linear, most of them obtuse; achenes slightly hirsute. 

 Mountains: Mont.— Colo. Submont.—Mont, Jl-Au. 



8 S. pallida (Porter) Rydb. Stem 4-8 dm. high, glabrous; leaves obovate- 

 spatulate to lanceolate, 5-15 cm. long, acute, entire, pale; heads very numerous, 

 in a dense, elongated-conic panicle; disk 5-6 mm. high; bracts oblong or Unear- 

 oblong, glabrous; achenes glabrous or nearly so. >S. speciosa pallida Porter, 

 Hills : S.D.— Neb.— Colo. Plain— Submont, Au-S. 



