546 FROM FORT BENTON TO LATITUDE 49° 30’. 
becoming more stony and sterile, and few flowers are seen, excepting in the little valleys of the 
numerous spring-brooks, where there are rich grass and many flowers; most of which, how- 
ever, have already been collected. In sixteen miles crossed another fine creek, sixteen feet wide, 
which I named ‘*Beaver-Dam creek,’ on account of the numerous beaver-dams in it. In three 
miles more we saw on the right hand, far below us on the plain, a considerable creek, which 
empties into the Teton nine miles from the mountains. There is no timber upon its banks, which 
are densely overgrown with thickets of birch and willow bushes. In twenty-one and a half 
” 
miles struck the Teton river, which here runs due east. The river spreads into several channels, 
running with a swift and shallow current through a level plain almost destitute of grass, the soil 
of which is composed of small stones and gravel as in the river-bed. There is but little timber, 
which is dwarf cotton-wood and willow. The river forks just above our camp, and enters the 
mountains through narrow gorges, affording no valley or pass whatever. The blue peaks of 
the Highwood mountains were visible from a butfe near camp, and I took bearings, as also on 
Heart mountain. 
May 20.—Morning oppressively warm. The country we are passing over is a stony plain, 
intersected by numerous spring-brooks running through deep, narrow valleys, in which the soil 
is good. Tracts thickly wooded with scrub-pine, and many marshes or quagmires in the valleys, 
rendered travelling slow and laborious. Considerable snow was seen low down on the mount- 
ains, and some even in the valleys. Specimen No. 66, a beautiful bell-shaped flower of a 
golden yellow, was found by the side of a snow-bank six feet deep. Continued a course along 
the base of the mountains, which now trend to the northwest, are more detached, and descend to 
the plain by a succession of hills densely timbered with pine of a fair size. Many of the peaks, 
however, still preserved their rugged character, having perpendicular rock after reaching within 
three hundred feet of their summits, rendering it impossible to ascend them from this side. In 
the afternoon the Highwood mountains were still visible, and I took bearings. The ‘Three 
Buttes” are just discernible in the northeast. Saw two grizzly bears digging roots. They are 
very poor at this season, and their skins are worthless. These bears were very timid, and ran off 
when we were within half a mile of them. This is generally, if not invariably, the case with 
the grizzly bear when in the plains. They are dangerous only when wounded, or come upon 
unexpectedly ina thicket. In the afternoon crossed many small brooks, which are doubtless the 
headwaters of Birch river—a large fork of the Marias river—which I hoped to reach to-night ; 
but finding it impossible, encamped on one of its forks at the foot of a lofty peak of the mountain. 
The country has been improving for the last fifteen miles, and this creek runs through a rich 
valley wooded with small poplars, and possessing a more luxuriant vegetation than I have yet 
seen. Collected seven new varieties of flowers. Ascended a lofty spur of the mountain, and 
found its summit to consist of granite and soft, red sandstone. Had a heavy thunder-storm in 
the evening ; previous to which I heard a noise in the mountains like the discharge of artillery, 
resembling the reports and explosions mentioned by Lewis and Clark and others. I have noticed 
this phenomenon several times, and conclude that it is occasioned by distant thunder-storms, either 
in the mountains or beyond the dividing ridge. Made to day 21.3 miles. 
May 21.—Moved early, and, after passing many small brooks and lakes, or ponds, struck Birch 
tiver just below where it issues from the mountain. Three miles after entering the defile, the 
river forks in two streams of nearly the same size. There is probably no pass here, as there are 
no signs of a road or trail, and the river evidently does not head far up in the mountains, which 
are lofty and very rugged, and then slopes densely timbered with fir. On the summit of a high 
range of hills next the river I collected in little grassy openings among the pines, eight new 
flowers, and in the valley four more. Each specimen has been carefully numbered and labelled 
with a description of place where found, color, &c. ‘The soil here is rich, and the country gen- 
erally better than any yet passed over. Birch river is timbered with cotton-wood, willow, and a 
. great quantity of yellow or gray birch, from which it takes its name. ‘This is the largest fork of 
