Dr. Nagy I. Zoltán szerk.: Fragmenta Mineralogica Et Palaentologica 2. 1970-71. (Budapest, 1971)

Micropaleontological descript

Jona Order; P ORAMINIF KRIDA Eichwald I83O. Family: GLOBIGERINIDAE Carpenter, Parker et Jones 1862. Genus: GLOBIGERINA d'Orbigny 1826. Globigerina ampliapertura Bolli (Plate I. 1/a-c) Globigerina ampliapertura Bolli n.sp.

, 1957» Bull. US. Nat.Mus, 215, P. 108, pl.

22, figs. 5a-7b. Description. Test of four whorls. The last whorl consists of four chambers. Chambers slightly oval, tightly disposed, building up a trochospire. Dorsal surface convex; sutures depressed, radial on both the ventral and the dorsal surfaces. Umbilicus relatively small, deep, often filled with sediment. Aperture intraumbilical, wide and high, forming an asymmetrical arch, delimited by a narrow, rim-like

, sometimes scarcely discernible lip. Apertural face flattened; differs from the other parts of the chambers. Note. Readily recognizable by means of its characteristic, large aperture, which is intraumbilical (in distinction from Globorotalis /T./ increbescens)

. Transitional forms occur In the lower beds of the Buda Marl. Occurrence. Common in the Cylindroclavulina cylindrica Zone of the Buda Marl. Disappears in the Eocene/Oligocene transition and reappears in the Kiscell Clay only, - Budapest region and the Bükk Mountains foreland.