Conceptual illustration of a Permian forest. The Permian, a geologic period which spans 47 million years from the end of the Carboniferous period 298.9 million years ago to the beginning of the Triassic period 251 Mya, was the last period of the Paleozoic Era. Rich forests were present in many areas, with a diverse mix of plant groups. The southern continent saw extensive seed fern forests of Glossopteris flora. Terrestrial plants broadly diversified during the Permian Period as plants shifted to gymnosperms, plants with their offspring enclosed within seeds. Plants include Calamites, Lepidodendron, Bjuvia, Cordaites, Glossopteris, lycophytes, Sigillaria, horsetails, early tree ferns, and ferns.