In ascending the hill of La Grange, we first encountered the rattlesnake, two of which we killed. This is the highest northern point at which we have observed this species on the Mississippi. I observed on this elevation small detached masses of radiated quartz, cinnamon-colored and white, together with an ore of iron crystallized in cubes. Having cursorily examined the environs, the expedition again embarked. It was 1 o'clock when we entered Lake Pepin. This admired lake is a mere expansion of the Mississippi, having a length of twenty-four miles by a varying width of from two to four miles. During this distance there is not the least current during calm weather. The prospects, in passing through this expanse of water, are of the most picturesque kind. Its immediate shores are circumscribed with a broad beach of gravel, in which may be found rolled pieces of the chalcedonies, agates, and other species of the quartz family, which are characteristic of the drift-stratum of the upper borders of the Mississippi. On the eastern shore, at a short distance from the margin, there is a lofty range of limestone cliffs. On the west, the eye rests on an elevated formation of prairie, nearly destitute of trees. From this plain several conical hills ascend, which have the appearance, but only the appearance, of artificial construction. The lake is quite transparent, and yields several species of fish. The most remarkable of these is the _acipenser spatularia_, of which we obtained a specimen. It is also remarkable for its numerous varieties, and the large size of its fresh-water shells. I procured several species of _unio_, which, from their size and character, attracted my attention, particularly to the subject of this branch of American conchology. Several of these, from the duplicates of my cabinet, have attracted the attention of conchologists.[100] Lake Pepin receives a river from the west called the Ocano, or more properly _Au Canot_; its mouth having been, in former times, a noted place for concealing canoes during the winter season.[101] At a point, on the east shore, about half way down the lake, where a small stream enters, we were informed there existed the remains of an old French fort, or factory; but we did not land to examine them. [100] Silliman's Journal of Science, 1823; also, Trans. Am. Phil. Soc. [101] Travellers who are disposed to regard La Hontan's fiction of his purported discoveries on _Rivier la Longue_, as entitled to notice, have suggested _this_ river as the locality intended. Nicollet, otherwise reliable, has gone so far as to call it La Hontan River.