Permian Period, Georgia Perimeter College. Summary of important events in Permian history, including the rise of the synapsids (mammal-like reptiles), with examples like Dimetrodon.
Permian Period Animal Printouts, Enchanted Learning-Zoom Dinosaurs. Brief, inadequate summary of the Permian Period, but good non-technical descriptions of the famous Permian amphibian Eryops, and the sail-backed pelycosaurs, including Dimetrodon. Fact sheets, K-3 appropriate printouts, and classroom activities are provided.
Permian Period, Palaeos. Scoll down to see brief descriptions of the history, tectonics, oceans, climate, and life of the Permian. You can click on linked families and orders of animals for technical details. Good picture of Late Permian gorgonopsids and a Late Permian bestiary in the linked section for the Late Permian. Specific sections concerning the Synapsida: Sphenacodontia,
and Edaphosauridae provide technical descriptions and images of these important Permian synapsid (mammal-like reptiles) families. Edaphosaurus was a plant-eating sail-backed synapsid, while Dimetrodon was a meat-eating sail-backed synapsid.
Introduction to the Pelycosaurs--Synapsids with Attitude, University of California, Berkeley. Short description of the pelycosaurs, a group of animals including the famous sail-backed synapsids (mammal-like reptiles) Dimetrodon and Edaphosaurus.