This postcard features a detailed image of an Isotelus trilobite, which is Ohio's official state fossil. The trilobite lived in a shallow sea that once covered Ohio during the Ordovician Period, approximately 440 million years ago. The specimen shown was collected in Highland County, Ohio, and measures 9 1/2 inches in length. The photograph captures the intricate segmented body and the overall shape of this ancient marine arthropod. The back of the postcard provides additional context, identifying the trilobite and its historical environment. It also credits Dan Cooper for collecting the specimen and Michael C. Hansen for the photograph. The postcard was published by the Division of Geological Survey of the Ohio Department of Natural Resources, indicating its educational and scientific significance.