Wednesday, 2d. After moving a few miles, we halted, and sent out hunters to kill a bison.[102] The confluent rattlesnakes are very abundant, particularly in and about the prairie dog villages; but neither their appearance nor the sound of their rattle excites the attention of our horses; the sagacity of Mr. Seymour's mule, however, seems superior to that of his quadruped companions. He appears to be perfectly aware of the dangerous qualities of these reptiles, and when he perceives one of them near him, he springs so abruptly to one side, as to endanger his rider. Fortunately none of us have been bitten by them during our pedestrian rambles. A recent trail of some war-party was this morning observed, leading across the river. The hunters returned unsuccessful, and we proceeded on until sunset to a distance of twenty miles. Great numbers of bisons were seen this afternoon, and some antelopes. Thursday, 3d. The morning was clear and fine, with a temperature of 57 degrees. The antelopes become more numerous as we proceed; one of them trotted up so near to our line as to fall a victim to his curiosity. A considerable number of the coquimbo, {64} or burrowing owl, occurred in a prairie dog village of limited extent. They readily permitted the hunter to approach within gunshot, and we were successful in obtaining a specimen of the bird in good order. Upon examining the several burrows upon which the owls had been observed to be perched, we remarked in them a different aspect from those on which the prairie dog had appeared; they were often in a ruined condition, the sides in some instances fallen in, sometimes seamed and grooved by the action of the water in its course from the surface to the interior, and in other respects presenting a deserted aspect, and, like dilapidated monuments of human art, were the fit abode of serpents, lizards, and owls. The burrows on which we saw the prairie dog were, on the contrary, neat, always in repair, and evinced the operations of industrious tenants. This contrast, added to the form and magnitude of the dwelling, leads us to the belief that the coquimbo owl does not, in this region, excavate its own burrow, as it is said to do in South America and in the West India islands; but rather that it avails itself of the abandoned burrows of this species of marmot, for the purposes of nidification and shelter. On our arrival at our mid-day resting-place, on the bank of the Arkansa, the water of the river was potable, but in a few minutes it became surcharged with earthy and stercoraceous matters, from the sweepings of the prairie by the late rain, to such a degree that our horses would hardly drink it. There remained however, a short distance below, a small stream of beautifully pellucid water, which rapidly filtrated through a fortuitous embankment of sand and pebbles, and strongly contrasted with the flood with which it was soon again to intermingle. Our travelled distance to-day was twenty-three miles.