NATURAL HISTORY REPORT ON WESTERN DIVISION. 221 
of the Cascade mountains, about as far as 48° of latitude. From here north it is less defined, 
the forests and plains being intermingled up to 49°; the summits and northern exposure of the 
hills being covered by forests, while the valleys and southern slopes are nearly destitute of trees. 
Returning to the south from Fort Colville, we again met with the open plains a little south 
of the Spokane river, which may, therefore, be considered their northern boundary east of the 
Columbia. Towards the east the Coeur d’Alene mountains were seen, covered with forest, 
limiting the plain in that direction. ‘The Plains” comprise not only high and almost level table- 
lands, but steep hills and deep valleys. South of the Snake and Columbia rivers all the country 
passed through was of this character. The vegetation of these various sub-regions is very dis- 
similar; on the high spurs east of the mountains, commonly very stony and dry, scarcely any 
plants were flowering during our journey. Artemisia or “wild sage,” and Purshia or “ grease- 
wood,” were the characteristic shrubs. The withered remains of some umbelliferous and other 
plants were noticed, and grass was poor and dry. In the valleys a sandy but better soil pre- 
sented several different vegetable sub-regions. The high gravelly terraces bordering some of the 
valleys were covered with a dry but dense growth of grass. Near the streams occurred some 
rose and cherry bushes, the usual poplar and willows, and a few small birch and pine trees, 
with some flowers still blooming. North of the Yakima the larch tree was abundant on the 
mountains, with the long-leaved pine and the black fir, in nearly equal proportions. Near Fort 
Colville a few birch trees of large size were seen, having a laminated bark, of which the Indians 
make canoes. The vegetation of the Spokane plains resembles that west of the Columbia river, 
as far as could be seen, from its withered state, when we passed through it. Among the animals 
peculiar to the plain region, the most remarkable are the badger, ‘sage fowl,” sharp-tailed grouse 
or prairie fowl, horned lizards, and rattlesnakes. 
South of the Snake river, to the north of the Wallah-Wallah, the country resembles that near 
the Yakima river, but the hills are better covered with grass, and the valleys more fertile. 
Several peculiar plants were seen here. From the southern banks of the Columbia, to the south- 
west, we could see a mixed country of high table-lands and undulating plains, with the wooded 
outline of the Blue mountains in the distance. After entering the gap of the Cascade mountains 
at the Dalles, the forest again appeared with a similar succession of trees from east to west 
(described) when crossing them (in the opposite direction) in August. A much milder climate 
prevailing on the west side of the Cascade mountains, was accompanied by the second flowering 
of several species of plants in November and December. Among those seen were the straw- 
berry, blue and yellow violets, and various garden plants. 
Besides the animals seen or collected on the route, several are said to inhabit the forests. The 
deer, (two species,) black bear, and a brown variety of lynx and racoon, are not uncommon. 
Beavers are said to be found on the streams, where the mild winters preclude the necessity of 
building dams to prevent the water from freezing too deep. The panther or cougar is also 
reported to be sometimes found. The mountain sheep undoubtedly inhabits the limits of per- 
petual snow—a skin being seen in possession of an Indian near Mount Rainier. 
The rivers flowing into the Columbia have a peculiar animal as well as vegetable character, 
which is much the same on both sides of the mountains. Several kinds of water-bird frequent 
them, especially in the autumn, only emigrating to the west side in winter. 
Three fine species of trout were obtained, but unfortunately destroyed; one of them appears 
to be peculiar to the streams on the eastern side. A few other kinds of fish were also seen. A 
collection of all the fresh-water shells seen was made. A species of crawfish was met with, even 
to the headwaters of its branches, and in the Columbia occurs eight and ten inches long. It is 
said to be a very good substitute for lobsters as an edible. 
Respectfully, &c., J. G. COOPER, M. D. 
Capt. G. B. McCrextan, 
Corps of Engineers, Commanding Expedition. 
