Matskási István (szerk.): A Magyar Természettudományi Múzeum évkönyve 82. (Budapest 1990)

Dulai, A.: The Lower Sinemurian (Jurassic) brachiopod fauna of the Lókút Hill (Bakony Mts., Hungary). Preliminary results

than 100 layers (Fig, 2a). Four intervals were collected bed-by-bed (A: lst2nd layer, B: 35th-45th layer, C: 51st-57th. layer

, D: 84th-97th layer). Further on, the A, B, C, D signs on the figures refer to the four intervals. The numbering of layers used by the current collection agrees well with the numbering of the previous sampling, made by the Hungarian Geological Institute (see the 115th layer). So the two collections can be compared stratigraphically. THE REVIEW OF FAUNA The composition of the collected fossils: 95% brachiopods, 3.5% ammonites, 1.5% bivalves (Fig. 2b). The bivalves are under study by I. SZENTE (Eötvös Univ. ) . Ammonites Ammonites were found in two layers (85th and 87th) in big number and they are very rare or missing from the other layers. GÉCZY (1971a) determined the lowest (Bucklandi) zone of the Sinemurian stage on the basis of ammonites collected around the 100th layer. The ammonites found in the 85th and 87th layers during the present collection, confirm the Sinemurian age on the basis of determination by GÉCZY: Arnioceras sp

. Angulaticeras sp

. Trachylytoceras sp

. Juraphylli

tes sp

. Lytoceratidae sp. Atractites sp

. Nautiloidea sp. The three ammonites clasts found in the 2nd layer from the bottom of sequence did not give any valuable -stratigraphical information. But it is probable that on the contrary of previous suppositions (GALÂCZ 1988), the formation of Pisznice Limestone does not expand down to the Hettangian stage. It means, that in this case only one zone, the lowest (Bucklandi) zone of the Sinemurian, was collected. Fig. 1. Situation map showing the position of the Lókút Hill section Brachiopods Taxonomic examinations- As a result of the oneweek collection, more than 2000 specimens were found, but because of the bad preservation only some 20%, i.e. about 400 specimens could be determined. I could separate 36 species of 15 genus on the basis of the determined specimens: Calcirhynchia ? plicatissima (QUENSTEDT

, 1852) Cuneirhynchia ? cartieri (0PPEL, 1861) Cuneirhynchia ? retusifrons (0PPEL, 1861)