Browse Items (4 total) Tags: Pennsylvanian Browse All Browse by Tag Search Items Sort by: Title Creator Date Added Calamites Calamites fossil. Ancestor of Equisetum alethopters fern. Tags: Arkansas, Fossils, Geology, North America, Pennsylvanian, Plants, United States, Washington County Algae Algae fossil Tags: Brown, Fossils, Geology, Gray, Kansas, North America, Pennsylvanian, Plants, United States, Yellow Calamites An ancestor of the present "horse tail", Equisetum; Pennsylvanian Tags: Arkansas, Brown, Fossils, Geology, North America, Pennsylvanian, Plants, United States Fern Slab showing a cast of ferns from a coal bed. Tags: Arkansas, Fossils, Geology, Gray, North America, Pennsylvanian, Plants, United States Featured Item Dinosaur Cast and mold of Arkansaurus fridayi.
