MILIOLIDAE - Acta Palaeontologica Polonica

120 EWA l..UCZKOWSKA
rer). The specimens sectioned belong to the micro generation; PD 10 J!,
(Text-fig 39/1). The juvenile stage is irregularly triloculine, then biloculine
chambers are added. The size of the juvenile stage is very small in
comparison with the biloculine stage.
Remarks. - Our specimens correspond to the topotypes from Wieliczka
and to Reuss's illustration. Large forms identical with Pyrgo anodonta
(Karrer) and P. bulloides calostoma (Karrer) from Kostej are also found
among them. In the comparative materials from Lapugiu there are also
forms with the apertural tooth resembling that of P. anodonta and others
with the protruded and truncate penultimate chamber, as in P. truncata.
As the nearly spherical shape is characteristic of both forms, and the
chamber extension may be regarded as intraspecific variation, they have
been recognized as synonyms. It seems that P. truncata (Reuss) may be
considered an individual species, and not a subspecies of P. bulloides
(d'Orbigny), as its circular shape and broad apertural tooth distinguish it
from this species. P. truncata differs from P. simplex (d'Orbigny) in its
distinctly narrower and more oblique chamber sides and in the protruded
penultimate chamber.
Distribution. - Poland: Tortonian (Brzeznica, Chelm n/Rabq, Gliwice
Stare, Karsy, Krywald, Ligota Zabrska, Rybnica, Wieliczka, Zrecze).
Czechoslovakia: Tortonian, Zidlochovice. Romania: Tortonian, Kostej in
Banat, Lapugiu de Sus.
Genus Pyrgoella Cushman & E. M. White, 1936
This genus contains forms with a spherical test and the last
chamber covering all but the penultimate chamber, like Pyrgoella globijormis
(Karrer) and P. ventruosa (Reuss), and forms with a more regularly
oval shape of the test, oval or triangular in cross-section. The last
chamber of the latter does not cover the penultimate one, but, what
is more, leaves also the third chamber visible between them, as in
P. controversa (Bogdanowich). Such forms with the third chamber exposed
and with a tongue-like flap in the aperture are usually recognized as
belonging to the genus Miliolinella, which is not correct in the light of the
materials studied. The test of these forms shows a tendency to become
spherical or egg-shaped, and the last chamber in adult specimens embraces
nearly all the chambers of the preceding whorls, whereas in the genus
Miliolinella the test rather shows a tendency to become flattened, and
there are three, four or five chambers visible from outside. The internal
structure of Miliolinella is initially cryptoquinqueloculine, then pseudotriloculine,
having one acute angle, and two angles, between the last three
chambers, exceeding 120°, and in the genus Pyrgoella the initial part is
pseudotriloculine, then biloculine.