The Permian, geologically speaking, was a period of transition. Toward the close of the Carboniferous there were many important earth movements which raised the level of the land and tended to enclose the area of water in what is now Eastern Europe, and to make a continental area with inland seas. Many of the Carboniferous genera are found to extend through the Permian and then die out, while at the same time others became quite extinct as the physical conditions changed. The seed-bearing plants became relatively more important, and though the genus _Cordaites_ died out at the end of the period it was succeeded by an increasing number of others of more advanced type. When we come to the older Mesozoic rocks, we have in England at any rate an area which was slowly submerging again. The more important of the plants which are preserved, and they are unfortunately all too few, are of a type which has not yet appeared in the earlier rocks, and are in some ways like the living _Cycas_, though they have many characters fundamentally different from any living type. In the vegetation of this time, plants of Cycad-like appearance seem to have largely predominated, and may certainly be taken as the characteristic feature of the period. The great Lycopod and Equisetum-like trees of the Carboniferous are represented now only by smaller individuals of the same groups, and practically all the genera which were flourishing in the Carboniferous times have become extinct. The Cycad-like plants, however, were far more numerous and varied in character and widely spread than they ever were in any succeeding time. Still, no flowers (as we understand the word to-day) had appeared, or at least we have no indication in any fossil hitherto discovered, that true flowers were evolved until towards the end of the period (see, however, Chapter X).