In _Oregon_ a treaty has recently been concluded with portions of the Callapooya and Twallaty tribes of Indians, who cede to the United States a large tract of the most valuable lands in the valley of the Willamette. These Indians refuse to leave that portion of the country, and will probably continue to reside within the limits of the reservations. Unlike the tribes to the east of the Rocky Mountains, they are desirous of adopting the habits of civilized life, many of them being now in the service of the whites as laborers. In Illinois, Missouri, Iowa, and along the whole course of the Upper Mississippi, great damage has been done by an unusual and long-continued flood of that river. Many towns of considerable size have been quite overflowed. At St. Louis, during the greater part of the month of June, the levee was entirely submerged, and all the stores upon Front-street filled with water to the depth of several feet. For a vast extent along the Mississippi, Missouri, and their tributaries the bottom lands have been submerged for so long a time as to destroy the growing crops. It is the most disastrous inundation which has occurred for several years. Three distinct shocks of an earthquake were felt at St. Louis on the 2d of July. The morning was somewhat cool and cloudy, followed not long after by a slight rain, with thunder. In the afternoon the weather cleared up, and so remained for the remainder of the day. The cholera has appeared at several places in the West, more especially on the line of the Mississippi. It does not appear, however, to have assumed a decidedly epidemic character. The troops under the command of Col. Sumner, on their way to New Mexico, have suffered severely; as well as the trains of traders. The small pox has committed terrible ravages among the Sioux and other Indian tribes on the plains of the Northwest. In January the weather was extremely cold, and some 40 or 50 of the Indians in exposed situations were frozen to death. Affrays have taken place among various tribes of Indians in Iowa, Wisconsin, and Minnesota. A steamer has recently set out from St. Louis, with about 100 voyagers bound for the Rocky Mountains. The steamer is destined for the mouth of the Yellowstone, about two thousand miles up the Missouri, the head of steamboat navigation. From this point the passengers will proceed in Mackinaw boats to the falls of the Missouri. Most of the passengers are employees of the American Fur Company. Dr. Evans, U. S. Geologist, is of the number; and two Jesuit missionaries, Fathers De Smedt and Hæken, take the opportunity to visit the wild tribes of Indians near the Mountains, among whom they intend to remain for two or three years.