Fourth, Coarse white pudding-stone or conglomeratic and sandstone, of a deep red colour, alternating with each other, and with beds of fine white sandstone, and resting against the granite in a highly inclined position. This rock contains well preserved remains of terebratulæ, productus, and other bivalve shells. These are usually found on or near the surface of large nodules of a fine flinty stone, closely resembling petrosilex. The same rock also contains an extensive bed of iron ore; and from its eastern side flows a copious brine spring. About this spring, which had evidently been much frequented by animals, we saw the skulls of the male and female big horn, the bones of elk, bisons, and other animals. The granite, which succeeds the sandstone last mentioned, is of a dark reddish brown colour, containing a large proportion of felspar, of the flesh-coloured variety, and black mica. The crystalline grains, or fragments of the felspar, are large, and {202} detached easily, so that the rock is in a state of rapid disintegration. This granite rises abruptly in immense mountain masses, and undoubtedly extends far to the west. The little river, on which our camp is situated, pours down from the rugged side of the granitic mountain through a deep inaccessible chasm, forming a continued cascade of several hundred feet. From an elevation of one or two thousand feet on the side of the mountain, we were able to overlook a considerable extent of secondary region at its base. The surface appeared broken for several miles; and in many of the valleys we could discern columnar and pyramidal masses of sand-rock, sometimes entirely naked, and sometimes bearing little tufts of bushes about their summits. Here met with a female bird, which closely resembles, both in size and figure, the female of the black game (tetrao tetrix); it is, however, of a darker colour, and the plumage is not so much banded; the tail also seems rather longer, and the feathers of it do not exhibit any tendency to curve outward, which, if we mistake not, is exhibited by the inner feathers of the tail of the corresponding one of the black game.