Dr. Nagy I. Zoltán szerk.: Fragmenta Mineralogica Et Palaentologica 5. 1974. (Budapest, 1974)

EVOLUTION LINEAGES IN THE STUDIED PROFILES 1. Turborotalia liverovskae - T. brevispira evolution lineage Pl. III., figs 5a-llc. Turborotalia liverovskae is a small, two whorlded form. The last whorl consist usually of five, rarely six chambers. The last whorl slightly embraces the previous one. Umbilicus shallow. The aperture is a low extraumbilical slit, bordered by a slender, lath-like lip. The aperture reaches the periphery. In the Buda Marl, from the Catapsydrax gortanii gortanii Zone onwards this species gradually changes, i.e. the number of the chambers decreases to four, with the regression of the fifth chamber. This change is observable not only in the adult, but also in the juvenile stage. The reduction of the number of the chambers is followed by change in the growth rate of the chambers. In the species Turborotalia liverovskae the chambers grow rapidly and evenly. The growth of the chambers in the transitional forms has a similar pattern. On the other hand the last chamber of Turborotalia brevispira specimens yielded by the Kiscell Clay is more elongated as compared to that of the above mentioned forms. This change took place during the formation of the Tard Clay, therefore it cannot be studied in Hungary. The first transitional forms appear in the Catapsydrax gortanii gortanii Zone of the Buda Marl. The appearance of the typical Turborotalia brevispira can be assigned into the Turborotalia increbescens Zone. The specimens collected from the Kiscell Clay slightly differ from the holotype

. 2. Turborotalia opima nana - T

. opima opima evolution lineage Pl. V., figs. 3a-7c. The first to recognize evolutionary relationship between these two subspecies was BOLLI (1957b), the author of these subspecies. The complete evolution lineage was figured first by BERGGREN (1969b). The evolution in Hungary took place as it has been shown by BERGGREN. The earliest T. opima opima appears at the base of the Egerian. 3. Turborotalia munda - T. obesa evolution lineage PL IV., figs. 5a-8c. Turborotalia munda is a small, stocky form, with 4 to 5 chambers in its last whorl. The chambers of the last whorl are of nearly the same size, the sutures are slightly depressed. The aperture is a low, umbilical-extraumbilical arch, bordered by a narrow lip. It is recognizable from the lower quarter of the Kiscell Clay onwards, that the last chamber of the species tends slowly to be inflate, attaining a greater size than that of the typical Turborotalia munda

. Simultaneously, the shallow umbulicus characterizing