Ledringhem Paleozoic era. Euramerica, also known as Laurussia, was a minor supercontinent created in the Devonian as the result of a collision between the Laurentian, Baltica, and Avalonia cratons. Euramerica became a part of the major supercontinent Pangaea in the Permian. In the Jurassic, when Pangaea rifted into two continents, Gondwana and Laurasia, Euramerica was a part of Laurasia. In the Cretaceous, Laurasia split into the continents of North America and Eurasia. The Laurentian craton became a part of North America while Baltica became a part of Eurasia, and Avalonia was split between the two. Ledringhem lies on the London-Brabant Massif,
Gondwana During the Devonian giant club mosses replaced the Baragwanathia Flora, introducing the first trees, and by the Late Devonian this first forest was accompanied by the progymnosperms, including the first large trees "Archaeopteris". The Late Devonian extinction probably also resulted in osteolepiform fishes evolving into the amphibian tetrapods, the earliest land vertebrates, in Greenland and Russia. The only traces of this evolution in Gondwana are amphibian footprints and a single jaw from Australia. The closure of the Rheic Ocean and the formation of Pangaea in the Carboniferous resulted in the rerouting of ocean currents which initiated an Ice House period.