Vörös A. szerk.: Fragmenta Mineralogica Et Palaentologica 16. 1993. (Budapest, 1993)

are arched at beginning and slightly angular after that in cross section. The crural processes are not too high. The transverse band has broken. The loop is probably quite long. Remarks: The species was first described as "Waldheimia" sospirolensis by Uhlig (1879). My specimens are very similar to Uhlig's specimens in external characters, but the internal characters refer to the genus Lobothyris. The only difference is that the loop is much longer than it is typical at Lobothyris. Some of Uhlig's figures show a weak median septum from outside view, others not. Unfortunately the internal characters of his specimens is unknown. A considerable part of the loop is missing, so the exact determination is impossible, because this was the only specimen from the Bakony Mts. suitable for serial sectioning. Distribution: According to Aimeras (1964), L. ? sospirolensis is Sinemurian in age. The species was reported from the Southern Alps and the Transdanubian Central Range. Lobothyris ? sp. (Plate II: Fig.'

1; Text-fig. 17) Material: 2 fragmentary specimen from Szesztra-hegy. Dimensions (mm): Specimen M.93.13. (Text-fig. 17) length: 23.0, width: 19.1, thickness: 10.5. Description - External characters: Medium-sized to large shell, elliptical in outline. The width is smaller than the length, while the thickness is smaller than half of the length. The angle between the lateral margins is about 88°. Biconvex form, the convexity of pedicle valve is greater than the the convexity of brachial one. The maximum width is situated at half of the length, the maximum convexity is at the posterior third. The beak is medium-sized. The lateral commissures and the anterior commissure are straight. Both valves are smooth. Internal characters: There were no adequate specimens available for serial sectioning due to the paucity of the material. Remarks: Only two fragmentary specimens were found and the internal characters are unknown. No median septum has been observed from outside, therefore specimens were classified to the genus Lobothyris with question mark. The specimens characteristically differ from the other Lobothyris species: they are not biplicate than L. ? subgregaria. Hatter than L. andleri, much wider and more angular than L. ovatissimaeformis, bigger and more irregular in outline than L. ? complanata. Iext-fig. 17: Drawing of Lobothyris ? sp., Szesztra-hegy