L. Hably szerk.: Studia Botanica Hungarica 22. 1990 (Budapest, 1990)
They contain typical xerophylous elements like Zizyphus , Dryophyllum and even those plants are armed with xerophylous features which have no xerophylous character at some other contemporary assemblages or in other periods. Such species are the Platanus neptuni and the Paleocarya orsbergensis . The Upper Oligocène floras have no xerophylous character at all. Generally we meet with large leaf surfaces, at some Daphnogene finds we can even recognize a drip apex as well. Smilax is present, which is a tropical - subtropical liana. It has species living recently in the Mediterranean region, but the leaves of these ones are always small and prickled. Its large leaves with intact margin denote a humid climate abounding in precipitation. The Upper Oligocène flora of Vértesszőlös does not indicate a strong deterioration of the climate as it was measured on the basis of 0 isotope measurements indicating the temperature of the sea water. If we are assigning the flora, according to zones of vegetation, to subtropical forests, more exactly speaking, subtropical rain-forests, we can roughly outline the climate on the basis of recent analogies. The subtropical zone is formed at the boundary of the tropical and temperate zones in a wide belt. In this 'transitional zone', one season is dominated by the tropical, the other one, by the temperate elements. The climate is warm, humid, mild frost can possibly occur sometimes. In our days, we can meet this climatical and floristical zone from the spatial respect. In my opinion, we can interprète this climatic model in temporal dimension as well. As we know about a wide transitional zone between the tropical regions and the temperate zone, the same way we have a temporal transition between the Cretaceous-Eocene tropical floras and the temperate Pliocene floras in a broad temporal interval. This state was existing during the Oligocène and the Miocene as well. As there are different vegetation zones within the subtropical regions like subtropical rain forests, laurophylous forest, hard-leaf evergreen forests etc., the same way we can meet different types of assemblages during the Oligocène and the Miocene, respectively, on a given area. These are governed partly by climatical factors, ecological space as well as competition within the populations clustered in assemblages and, inside and outside the assemblages. During the Egerian, a subtropical rain forest used to exist around Vértesszőlős. The intruding Arctotertiary elements were faced not with a withdrawing but a dominant subtropical flora, thus they were condensated into intrazonal assemblages occupying the biotopes unfavourable for the Palaeotropical elementsAcknowledgements: I would like to thank for their valuable help to those who were of great help to me in preparing the current publication. First of all, the late István SKOFLEK who offered the chance of investigating this floristical assemblage and was of great help to me in all phases of this work. I would like to express my gratitude to Professor Tamás BÁLDI for the determination of the macrofaunistical remains and András NAGYMAROSY for the determination of the nannoplankton, ensuring a safe and exact chronological assignment, as well as to Dr. Z. KVAÍEK for his valuable advice. Let me thank for the technical assistance of Judit ESZTERGÁLYOS as well .
