Kaszab Zoltán (szerk.): A Magyar Természettudományi Múzeum évkönyve 76. (Budapest 1984)
Kordos-Szakály, M.: New data to the Miocene flora of Nógrádszakál (Hungary)
sporadically. It can be separated from Populus balsamoides on the basis of the shape of the leaf margin (the leaf width of P. populina is greater than its length and is not so finely toothed). The length of the specimens is between 5 and 7 cm, width between 5.5 and 7.3 cm. Among monocotyledonous plants representatives of the genus Smilax and palm are the most important. A fragmentary specimen of Smilax came to light from the Bertece valley. Since its base, with the features characteristic for the genus is clearly recognizable it can be identified with certainly. In the Miocene its occurrence was already sporadic in our country. Today it is a creeper of the tropics and the subtropics. Palms are elements of the locality at Paris stream ; two remains may be identified only to the family. In addition to them Phonecites is also present. It had an important role in the composition of the vegetation of Europe, the climate of which was tropical in the Eocene. In spite of the correspondence of species of great number of individuals common in the floras of the Paris stream and of the Bertece valley, there are also significant differences between the two localities. It can be explained by the differences in their geological age and their biotopes or sedimentary conditions. The remains of the Bertece valley were certainly deposited simultaneously with the beginning of andésite volcanism, while the impressions of the Paris valley were deposited after this process. The age of the Mátra Volcanic Formation is 14.5 + 0.4 million years according to the K/Ar method (HÁMOR & SZENTG ORGYi 1981) so there is at least a difference of half a million years between the age of the plant impressions of the two sites. In the Bertece valley there are many plants requiring definitely riparian conditions (Equisetum, Parrotia ). In addition to them species like Sapindus lingeri and Quercus species which require drier soil and a slope with southern exposure also appear in a relatively large number. In the valley of the Paris stream a more varied flora living in definitely riparian biotope came to light. The many Populus, Ulmus, Salix and Alnus species as well as the more sporadical Ostrya, Equisetum, Pterocarya and palm species require wet, conditions in proximity of water. Conditions referring to a definite swam or moor did not exist because floral elements (e. g. Taxodium, Glyptostrobus) which could possibly indicate them are completely alosent. At the same time taxa the presence of which is indicate dreier soil and gallery-forest circumstances (like Ginkgo, Tetraclinis, "Acer"), as well as laurophyllous evergreen taxa (Prunus cfr. laurocerasus, Weinmannia, Quercus pseudoalnus) are also present in the flora of the valley of the Paris stream. The fossil plant assemblage of the Bertece valley was probably not transported there, certainly it was formed on site. It was destroyed and covered by a tuff dispersion. In the case of the valley of the Paris stream we may already come to the conclusions that accumulation conditions there refer to an accumulation by water and also to riparian circumstances of a delta character. In the closing material the cross-laminated structure and floral elements derived from different biotopes can be recognized. Vegetation-historical and stratigraphical position and connections of the Nógrádszakái floras The present level of the study of the floras found in the Paris and Bertece valleys at Nógrádszakái already enables me to re-evaluate the remains previously regarded as "Sarmatians" (ANDREÁNSZKY 1959) and also to investigate their connections with other classical Upper-Miocene paleoflora localities which have not been clarified either. At first I identified the degree of relationship between the flora of the Paris stream and the floras found at some other important localities in Hungary. For this purpose reexamined the floral lists of the localities Eger-Tihamér, Buják, Mikófalva, Sály, Bánhorváti-Verőbánya and Balaton published in literature (ANDREÁNSZKY 1959, JÓZSA-CZÁR 1955, VARGA 1955, IGALI-ZELLER 1955) and calculated for each locality the frequency values of those species which were also found at the Paris stream locality according to the formula: X 100 where C SP , = frequency of common species (%) C = number of common species (pieces) N x = total number of species in the flora used for the comparison (pieces).
