FEN a ee eee SDPO nee ee Nin ee ae ee ae ee) ee aa 
1900 | ROCKY MOUNTAIN HERBARIUM 197 
This is to be compared with S. mu/tiradiata scopulorum, but it is a much 
larger plant, with larger root-leaves and larger more open inflorescence. In 
being practically glabrous it also differs from that, and the upwardly u. lated. 
bracts especially distinguish it. 
It was abundant in loose gravelly soil in the open woods in the southern 
part of Yellowstone park, no. 6586, August 21, 1899. 
Machaeranthera superba —Probably only biennial, very numer- 
ously branched from the crown of the slender tap root: stems 
decumbent at base and widely spreading, 8—-15™ long, each 
simple below, but paniculately corymbose as to the inflorescence, 
their purplish hue masked by a minute cinereous puberulence ; 
root-leaves (mostly wanting at flowering time) oblong-lance- 
olate, with minute spine-tipped teeth, cuspidate-obtuse, tapering 
into a slender petiole somewhat shorter than the blade, whole 
length 4-6: stem leaves rather numerous, broadly linear to 
narrowly oblanceolate, entire or remotely denticulate, the teeth 
and apex cusped as in the root-leaves, minutely and softly sub- 
cinereous (scarcely canescent), 3-5°" long, smaller in the inflo- 
rescence: heads moderately large, disk about 1°™ high, nearly 
as broad; bracts of the involucre oblong, acute, tips mostly 
erect, decidedly tinged with purple which is only slightly 
obscured by the thin puberulence, very rarely a few gland-tipped 
haits on the Margins: rays 12 (more or fewer), a deep blue 
an yom 
. 
OF this Species, which was submitted with a number of others, Dr. Greene 
Writes as follo S: “A subalpine looking, too showy form of J/, canescens. 
- it cannot be referred to M/. subalpina, however much it looks like it at 
rst glance.” . 
a : 
i Species, of which | have typical specimens (the type number ia 
ag lam Satisfied that the species now proposed is amply distinct from 
thal egy as_understood (evidently) by Pursh, Nuttall, — 
i“ _ essentially erect plant even though branched from ee one 
misege : hg leaves are distinctly serrate or toothed, the bracts are evi oe 
is more Pped, the Pubescence is canescent rather than cinereous. AM. super 
Nearly allj 
4S Compared With A, canesc 
en 
tis distinguished from it by the almost entire absence of viscid 
ince that was written I have given much study to both of the 
