| Top--brachiopods that invertebrate paleontologists call scientifically, genus Phricodothyris; from the upper Pennsylvanian Deer Creek Limestone. Bottom--brachiopods of the genus Rhipidomella from the upper Pennsylvanian Oread Limestone. All specimens from the Shawnee Group, Virgilian Stage, Kansas. 303 to 301 million years old. |