1904] NELSON: ROCKY MOUNTAIN PLANTS 269 
rous above, often sparingly and minutely ciliolate-scabrous below 
and on the margins: heads several to numerous, usually in a 
crowded corymbose leafy cyme, turbinate-campanulate: involu- 
cral bracts broadly linear, in 3-4 rows, subacute or obtuse, erect, 
purple-tipped and margined, delicately ciliate, sometimes puberu- 
lent (as are the peduncles and pedicels): rays mostly fewer than 
15, purple or violet, pappus brownish: akene linear, half as 
long as the pappus, minutely ciliate and obscurely few-nerved 
(about 5). | 
. The literature of the subject seems to indicate the distinctness of the Aster 
occurring in the middle Rocky Mountains, which has been called 4. Stbiricus 
or A. Richardsonii. There can be no doubt that the true A. Sébiricus L. is 
foreign to North America and that it belongs where its name would indicate. 
It is equally clear that 4. Richardsonii is the name given to the 4. mon- 
fanus of Nuttall. Hooker (Fl. Bor. Am. 2:7) seems to have satisfied himself 
that A, salsuginosus (?) Less. equals 4. Espenbergensis Nees, and that the 
latter is undoubtedly the 4. onéanus of Rich, It follows, therefore, that the 
more southern form, if distinct from 4. Richardsonii Spreng. (re-characterized 
soni is a plant of the “barren country from lat. 64° to the Arctic Seas.” The 
‘Torrey and Gray Flora, which took into consideration these arctic forms only, 
emphasizes the characters which separate them from the species now pro- 
posed, viz., the tomentum, the serrate leaves, the squarrose involucre, many- 
ribbed achenia, etc. In the Sy#. FZ. Dr. Gray modifies this description so as 
to include all the European as well as the North American forms. 
Typical of the species now proposed are the writer's collections as follows : 
Yellowstone Park, 1899, nos. 6754 and 6610 (distr. as A. Sibiricus);, Big 
Horn Mountains, nos. 2334 and 7924, secured in 1896 and Igo! respectively. 
vAster incertus, n. sp.—Low, more or less cespitose-tufted, 
from small woody root-crowns and slender rhizomes: stems 
leafy, usually decumbent at base, rarely more than 14" high 
(occasionally nearly 24), sparingly cinereous-pubescent: leaves 
oblong to oblanceolate, 2-5°™ long, most of them tapering toa 
short petiole, glabrous or nearly so; the uppermost sessile by a 
Clasping base: heads solitary at the ends of the stems which are 
usually simple, rather large and showy (2-3™ broad): involu- 
Cral bracts spatulate, subacute, minutely soft-pubescent on the 
Margin, otherwise glabrous and green or sometimes purple 
margined : rays purple, rather numerous (25-50): pappus brown- 
ish, twice as long as the brownish nearly glabrous akene. 
