C-Oll POSIT AB (COMPOSITE FAMILY) 505 



Stem leaves lanceolate; plants usually more than 4 dm. high 

 (4-10 dm.). 

 Nearly or quite glabrous; the leaves ample, usually 



broadly lanceolate and sharply serrate . . . 7. S. serotina. 

 Glabralte or puberulent; the leaves numerous, usually nar- 

 rowly lanceolate,'SubeQtire or serrate above the mid- 

 dle .....,..,. S, S. elongata. 

 Pubescent at least above, usually on both stem and leaves. 

 Stem and leaves more or less hirsute, often scabrous and then 



somewhat canescent, , , . . . . . 9. S. canadensis. 

 Stem and leaves densely canescent. 



Plants rather tall (3-6 dm.); inflorescence usually foliar- 

 bractedl 

 Panicle usually long and narrow; involucral bracts obtuse 10, S. pulcherrima. 

 Panicle usually short and broad; involucral bracts acute. 



Floral bracts ovate to lanceolate . . . .11. S. mollis. 



Floral bracts lanceolate to linear . . . . 12. S. trinervata. 



Plants mostly low (1-3 dm.), finely cinereous . . .13. S. nana. 

 Kays mure numerous than the disk-flowers; recepta^e flmbriolate; 

 inflorescence corymbose. ' ' 



Leaves linear, dark green .' . . - > 14. S. occidentalis. 



Leaves narrowly oblong-lanceolate, pale green . . „ . 15. S. camporum. 

 Involucral bracts longitudinally , striate; the heads in a congested 



corymb . , . . . . . ... 16. S. rigida. 



1. SoUdago paUida (POTter) Rydb. Bull. Torr. Bot. Glub 33: 153. 1906. 

 Stout, erect, 3-8 dm. high: leaves ovate to lanceolate, thick and coria- 

 ceous, with prominent veins, pale or whitish: thyrsus narrow, of numerous 

 narrow spikerlike clusters, rather showy: heads 5-8 mm. high; the bracts 

 firm, narrowly oblong, very obtuse. (iS. speciosa pallida Porter, Bull. Torr. 

 Bot. Club 19: 130. 1892.)— Infrequent; Colorado. 



2. Solidago corymbosa Nutt. Trans. Am. Phil. Soc. 7: 328. 1840. Nearly 

 or quite glabrous, 1-3 dm. high: leaves firm and finely veined, entire or spar- 

 ingly serrate; stem leaves ciMate at base, oblong-lanceolate; the radical obovate 

 and narrowed into a petiole: heads rather large, 7-9 dm. high, generally few, 

 in 1 or more rounded or corymbiform clusters; bracts of the involucre about 

 as long as the flowers, acute: rays numerous and conspicuous. S. mvltiradiata 

 scopvlorum. [S. scopulorum (Gray) A. Nels. Bot. Gaz. 37: 264. 1904; S. 

 dliosa Greene, Pitt. 3: 22. 1896; S. rubra and S. laemcavlis Rydb. 1. c. 33: 

 649. 1904.]-^In the mountains of our range. 



3. SoUdago decumbens Greene, Pitt. 3: 161. 1897. Stems clustered about 

 the summit of a strong perpendicular root,_ stout, decumbent, 1-4 dm. high, 

 usually dark red, sparsely puberulent, as is also the foliage: lowest leaves 

 spatulate-obovate to oblanceolate, obtuse or acutish, more or less distinctly 

 serrate toward the summit; upper cauline leaves similar, but few and reduced; 

 all scabrous on the margin: inflorescence interruptedly thyrsoid: heads large; 

 bracts of involucre linear, obtusish, of firm, texture and carinate-nerVed, form- 

 ing about 3 series, the outer and shorter subulate-linear rather than linear: 

 achencs subcylindric, strigose-hispidulous; pappus very strongly barbellate^ 

 scabrous. S. humilis nana. (<S. oreophila Rydb. Mem. N. Y., Bot.Gard. 1: 

 387. 1900, is merely the larger form from the lower stations.) — ^Frequent in 

 alpine and subalpine stations throughout our range. 



4. Solidago dilatata A. Nels. Bot. Gaz^ 30: 196. 1900. Stems simple,! or 

 branched above, rather stout, glabrous, 4-6 dm. high: leaves glabrous, con- 

 spicuously reticulate-veiny below, minutely scabro-ciliate on the margins; 

 basal leaves oblong-spatulate to elliptic, tapering into a broad margined 

 petiole which is sometimes as long as the blade, either closely or remotely 

 serrate, mostly obtuse at apex, 10-15 cm. long; the stem leaves numerous, 

 sessile, mostly small (2-3 cm.): inflorescence nearly glabrous, the lower pe- 

 dunculate branches Lafy-bracteate: heads about 6 mm. high; involucral 

 bracts in about 3 rows, the 2 inner rows subecjual, minutely ciliate on the 

 margins, hnear, most of them obtusish and slightly dilated upwards: rays 

 8-10, conspicuous:, achenes short and lightly pubescent. — Authentic speci- 

 mens from tj^e locality only, Yellowstone Park. 



5. Solidago missouriensis Nutt. Journ. Acad. Phila. 7: 32. 1834. Stem 

 rather slender, 2-4 dm. or more high: leaves firm or thick; those of the stem 



