Pangea moves north. Ice-house to greenhouse (humid to arid) climate transition; dramatic reduction of coal swamps and amphibian habitat; some spore-bearing plants extinct; major evaporites; changes in internal and external carbonate invertebrate skeletons; major diversification of fusulinid foraminifera, ammonoids, bryozoans, and brachiopods, then major end-Permian extinction of fusulinid foraminifera, trilobites, rugose and tabulate corals, blastoids, acanthodians, placoderms, and pelycosaurs; dramatic reduction of bryozoans, brachiopods, ammonoids, sharks, bony fish, crinoids, eurypterids, ostracodes, and echinoderms. HISTORY AND SUBDIVISIONS In 1841, after a tour of Imperial Russia, R. I. Murchison, in collaboration with Russian geologists, named the Permian System to take in the “vast series of beds of marls, schists, limestones, sandstones and conglomerates” that surmounted the Carboniferous System throughout a great arc stretching from the Volga eastwards to the Urals and from the Sea of Archangel to the southern steppes of Orenburg. He named it for the ancient kingdom of Permia in the centre of that territory, and the city of Perm that lies on the flanks of the Urals. In 1845 he included rocks now known as Kungurian–Tatarian in age, and for a time the underlying strata (Artinskian, etc.) were known as Permo-Carboniferous, i.e. intermediate between Carboniferous and Permian (Dunbar, 1940).
