76 
ROUND-LEAVED WILLOW. 
skirt of this gelid region grew our present subject. We 
named this scene of toil and disappointment, Thorn- 
burgh’s Pass, or rather ravine, as no passage was prac- 
ticable, from the man who undertook to be our guide. 
It was in the central chain of the Rocky Mountains, 
and near to the pass of the Shoshonees, which the fol- 
lowing day we attained. 
We know of no species with which we can compare 
this Willow. The older branches are brown, smooth, 
and full of cicatrices left by leaves that have grown near 
together, giving the plant a stunted appearance; the pe- 
tioles are about ^ an inch long, with the younger branches 
hairy, the younger leaves are also somewhat so on the 
mid-rib. The leaves are nearly round, from lg to 3 
inches wide, and about the same in length, though some 
of the later produced leaves are ovate and sometimes 
even acute, both sides are equally green, the margin in 
the ovate leaves elegantly and very closely serrulated, 
but in the round leaves the serrulations are often nearly 
obliterated. The stipules are very large, wide, and 
heart-shaped, finely serrated with glandular points, at 
length they become membranaceous and deciduous. 
The male aments are oblong, large and sessile, the 
scales blackish and ovate, producing copious white hairs 
longer than their whole length, the filaments are very 
long. The female aments grow on thick stalks, and 
have the scales also very woolly; the capsules are 
smooth and ovate, acuminate; the style is long, ter- 
minated by 4 stigmas. The ovate leaved variety was 
collected by the late Dr. Gairdener, on the hills of the 
Wahlamet. 
