Preliminary analysis of the fossil vertebrates of the Canycn Ferry Reservoir area

PROCEEDINGS OF THE UNITED|[STATES NATIONAL MUSEUM Issued SMITHSONIAN INSTITUTION U. S. NATIONAL MUSEUM Vol. 103 Washington: 1954 No. 3326 PRELIMINARY ANALYSIS OF THE FOSSIL VERTEBRATES OF THE CANYON FERRY RESERVOIR AREA By Theodore E. White The Canyon FeiTy Reservoir will be located on the Missouri River below Townsend, the county seat of Broadwater County, Mont. The dam is being built about 1 mile downstream from the present Canyon Ferry Dam and Power Plant. The maximum pool will inundate an area approximately 25 miles long and 3 to 4 miles wide, and will include several known fossiliferous localities in Oligocene and Miocene sediments. The reservoir area includes one of the very few areas in the intermountain basins that have a complete succession of sediments from the Lower Oligocene well into the Middle Miocene. Fossil faunas are known from other intermountain basins in Montana but rarely do they embrace more than one of the time units represented here. These faunas are of special interest because they represent an environment totally different from that of the White River deposits of the plains and offer opportunities to study fossil faunas in the light of the principles of climatic zoning which have been worked out for recent faunas. Most of our knowledge of the Tertiary deposits and their faunas of the intermountain basins of Montana is the result of the explorations and research of the late Dr. Earl Douglass around the turn of the century. His studies have been published principally in the Annals of the Carnegie Museum. His explorations have been greatly ex-tended and enlarged by Dr. J. LeRoy Kay, of the same institution, whose assistance has greatly expedited the work of the River Basin Surveys. The studies by Douglass have been further augmented by those on the fossil rodents and lagomorphs by Dr. J. J. Burke, who 273552—54 1 395