6 BOTANICAL OBSERVATIONS IN WESTERN WYOMING. 
collect their summer tribute of melted snow, and cleave their way 
to the lower valleys through deep gorges, disclosing in steep mural 
faces the structure and succession of the underlying, highly in- 
clined, rocky strata. The lower undulating slopes, forming the 
natural divides between the numerous watercourses tributary to 
the main valley of Wind River, form irregular ridges often pre- 
senting smooth tabled summits, bedded with rich grasses inter- 
spersed with gaily colored flowers. Conspicuous among the latter 
are the bright golden-yellow heads of Balsamorhiza Hookeri 
Nutt., and Balsamorhiza sagittata Nutt., growing promiscuously, 
the close similarity of their flowers being curiously contrasted 
with their diverse foliage; even in the latter case, however, a ten- 
dency to assimilate (perhaps due to hybridization) is occasionally 
observed, in which the sharply hastate leaves of the latter species 
are irregularly gashed to resemble forms of the other. Besides 
these everywhere obtrusive forms, we may also note as character- 
istic of this district Geranium Fremontii Torr., Arenaria congesta 
Nutt., Arenaria Hookeri Nutt., Astragalus campestris Gray, Oxy- 
tropis campestris L., Lupinus sericeus Pursh, Hedysarum Mack- 
enzii Rich., Eriogonum flavum Nutt., and C alochortus Gunnisoni 
Watson. On al! the high rocky ridges of this section a charming 
variety of Phiow Douglasiit Hook. is met with, forming close, flat- 
tened cushions, and a prosasion of pure porcelain-white fragrant 
flowers. 
Along the borders of streams, with the prevalent willow growth, 
we find Betula occidentalis Hook.. Alnus incana Willd., and in the’ 
larger valleys Eleagnus argenteus Nutt. 
On the steeper mountain slopes, before alluded to as presenting 
an agreeable alternation of meadow and woodland, the smooth 
grassy expanses of the higher elevations, reaching an altitude of 
nine thousand feet above the sea level, reveal a distinctly subal- 
pine vegetation. We accordingly here encounter such well known 
forms as Sazifraga nivalis L., Eritrichium aretioides DC., Pole- 
montium confertum Gray, Lloydia serotina Reich., while appar- 
ently more distinctly characteristic of this particular range we 
note Townsendia spathulata Nutt., Townsendia scapigera D. C. 
Eaton and Bupleurum ranunculoides L. 
_ In the wooded districts Pinus fleailis is irregularly mingled with 
Pinus ponderosé and Abies Douglasii, while Pinus contorta forms 
* the pose exclusive growth of the interior ridges and alpine 
: ) 
