Kaszab Zoltán (szerk.): A Magyar Természettudományi Múzeum évkönyve 77. (Budapest 1985)

Kordos-Szakály, M. ; Kordos, L.: Morphotypes of Hungarian fossil Celtis (Urticales) stones

Fig. 4. Scatter diagram of the fossil Celtis morphotypes stony endocarps: (1 = height, 2 = width), a = pill, b = sphere, c = pillow, d = torpedo, e — oval, f = macro of this morphotype have no regular forms, wider (Rudabánya) and nearly spheroid forms could be equally found among them. During the investigation on the size variations among the morphotypes of fossil Celtis stony endocarps, we have been able to define the length: width ratio of the different morphotypes and demonstrate their dimensional variation as tendencies which accompanied their development through the geological ages. Dimensional decrease can be observed only in the case of the smallest pill types while the other ones show a definite and great dimensional change of 18-20%. This change, however, was not even. Dividing the degrees of dimensional changes into geological ages and summing up into rates, each 1 million years we obtained the following results : Age group I. Upper Miocene (10 mill, yrs) II. Pliocene (4 mill, yrs) III. Plio-Pleistocene (2 mill, yrs) IV. Middle Pleistocene (0.5 mill, yrs) V. Upper Pleistocene (0.1 mill, yrs) The dimensional changes of the fossil stones were only of a modest degree during the Upper Miocene, but were more pronounced in the Pliocene. The most significant increase occurred at the average relative change 2.4% 6.6% 5.6% 3.4% relative change (mill, yrs) 0.4%/mill. yrs 3.3%/mill. yrs 3.7%/mill. yrs 8.5%:mill. yrs