Szekessy Vilmos (szerk.): A Magyar Természettudományi Múzeum évkönyve 57. (Budapest 1965)

Rásky, K.: A contribution to the study of Tertiary plant remains from Hungary

ANNALES HISTORICO-NATURALES MUSEI NATIONALIS HUNGARICI Tomus 57. PARS MINERALOGICA ET PALAEONTOLOGICA 1965. A Contribution to the Study of Tertiary Plant Remains from Hungary By K. RÁSKY, Budapest There are described in the present paper the leaf impressions found in the tuff deposits of volcanic eruptions in Ipolytarnóc, North Hungary, namely: Centroplacophyllum paiaeoglaucinum n. g., n. sp., Erythrospermophyllum ipolytarnocense n. g., n. sp., and Ompkaleaephyllum weylandi RÁSKY. From the Middle Oligocène clay deposit of Budapest-Óbuda, Aleuriteophyllum nemejci n. g., n. sp., Scolopiaephyllum protoluzonense (RÁSKY) RÁSKY, and Caseariaephyllum kräuselt RÁSKY are herein published. From the Upper Eocene marl deposit of Budapest-Óbuda, the fossil occurrences of Macarangaephyllum palaeomonandrum n. g., n. sp., Alchorneaephyllum grambasti (RÁSKY) RÁSKY, Mdllotophyllum palaeomiquelianum n. sp. and Antholithus macarangaeformis n. sp., confirm the presence of these genera of Euphorbiaceae in the Upper Eocene of Hungary. I. Ipolytarnóc, North Hungary, Tertiary Centroplacophyllum paiaeoglaucinum n. g., n. sp. (Plate I, Figs. 1-2, Pt. II, Fig. 6, Pt. Ill, Fig. 7) Diagnosis gen. et sp. ; Leaves oboval-oblong, or oblong-oval, apex acuminate, base shortly cuneate or subrotundate. Length 8— 14 cm, greatest width between 4.5— 7.0 cm. Margin entire, locally slightly undulating or remotely crenate near apex. Petiole, if conserved, 5—6 mm long. Midrib prominent, incrassate toward base, slightly arcuate. Number of secondary veins 5—6 pairs, ascendent, arcuate, camptodrome, initially extending along midrib, domatia present in their axils. Secondary veins opposite at base, upward alternating. Also thinner intersecondaries arising from midrib. Tertiary veins rather few on impressions. Texture coriaceous. Remarks and comparison: The fossil leaf impressions of various size are favourably comparable with the leaves of the recent Centroplacus glaucinus PIERRE, a 10 — 20 m high tree living in the tropical forests of Gabon and Cameroun. The fossil leaf remains found are all recognizable among the leaf shapes of the recent species. PIERRE relegated the genus to the family Flacourtiaceae, allying it with the genera Scottelia (Dasylepis) and Erythrospermum. Later, E. GILG considered the place of the genus Centroplacus as uncertain in the family Flacourtiaceae. PAX relegated the genus to the family Euphorbiaceae, in 1931. It cannot be denied, however, that leaves of a similar type can be found in also quite different families, e. g., the leaves of Lacistema myricoides Sw., or Litsea (Tetranthera) oblonga WALL., are of the same type, but in details they still deviate from the leaves of both the fossil and 6 Természettudományi Múzeum Évk. 1 965.