Fossils are abundant in Indiana’s rocks, and Hoosiers commonly seek information about these relics of ancient life from the Indiana Geological Survey. The primary purpose of this circular is to provide information on the principles of paleontology and the major kinds of fossils found in Indiana. Many of the fossils illustrated in this circular are found in Indiana bedrock; some have been included to provide more information on the characteristics of the major groups of fossils. Another purpose is to stimulate interest in fossil collecting, a healthful pastime that may lead younger readers to a rewarding career. This account of ancient life concludes with a list of books that deal largely with fossils and earth history. Fossilized remains of primitive vertebrates are not discussed as they are rare in Hoosier rocks. Prehistoric plant life in Indiana is not considered, as Canright (1959) has recently described plants that grew in Indiana in the geologic past.