Terrestrial and Aquatic Mollusks of the Eocene Kishenehn Formation, Middle Fork Flathead River, Montana

The Kishenehn Formation of northwest Montana and southeast British Columbia hosts one of the most prolific and diverse assemblages of fossil nonmarine mollusks in North America. More than 76 taxa, of which 41 are newly described species, of middle Eocene to early Miocene terrestrial and aquatic gastropods have been collected and described. This paper reports on the discoveries made in the oldest part of the formation that is middle Eocene in age...