MILIOLIDAE - Acta Palaeontologica Polonica

MILIOLIDAE. FROM MIOCENE OF POLAND 141
Description. - Test nearly circular, robust, periphery broadly rounded;
chambers broad, semicircular in shape, narrowing towards the aperture,
middle chamber large, slightly convex, oval, tapering at both ends, fifth
chamber poorly visible; sutures distinct, depressed; wall thin; surface
covered with faint longitudinal bifurcated striae, placed mostly on the
periphery of chambers, wide apart at the base and more and more tightly
arranged towards the aperture, where they dissapear; aperture large,
semicircular, with low, quadrate, bifurcated tooth.
Variability. The intensity of ornamentation is variable from faint,
poorly visible striae on the lower part of the chamber to distinct ones
running along the whole chamber.
Remarks. - This species differs from Varidentella rotunda (Gerke) in
having a broadly rounded periphery, covered with thick striae. From
Cycloforina toreuma (Serova) it differs in its larger and more robust test,
semicircular aperture, quadrate tooth, finer striae and inflated sides of
chambers.
Distribution. - Poland: Lower Sarmatian, (Budy, Grzyb6w, Rytwiany,
Zrecze). USSR: Lower Sarmatian, Transcarpathians.
+ Varidentella reussi (Bogdanowich, 1947)
(part I, Pl. XIII, Figs Ia-c, 2a, b, 3; Part II, Text-figs 48, 49)
1947. Milialina reussi Bogdanowich; A. K. Bogdanowich, p. 21, PI. I, Fig. 4a, b.
1952. Milialina reussi Bogdanowich; A. K. Bogdanowich, p. 119, PI. 13, Fig. la-c.
1956. Milialina reussi Bogdanowich; V. M. Pobedina et al., p. 109, PI. 11, Figs 1-3.
1958. Milialina reussi Bogdanowich; I. V. Venglinsky, p. 83, PI. 16, Fig. 2a-c.
1961. Quinqueloculina reussi (Bogdanowich); V. J. Didkovsky, p. 50, PI. 10, Fig. 5.
1962. Quinqueloculina reussi (Bogdanowich); I. V. venglinsky, p. 74, PI. 4, Fig. la-c.
1971. Quinquelaculina reussi (Bogdanowich); L. S. Maissuradze, p. 48, PI. 4, Figs 1,2.
Material. - Over 1000 specimens (CoIl. No. F-193, Sec. No. 152-154,
274-284).
Dimensions: L 0.3-0.4; B 0.25-0.35; T 0.2-0.25.
Description. - Test broadly oval, tapering at both ends, periphery
broadly rounded; chambers broad, narrowing towards the aperture, last
chamber often extended and inclined towards the penultimate one, middle
chamber broad, inflated and slightly oblique, fifth chamber poorly visible
or invisible; sutures flat and broad; wall thin; surface smooth, dull,
wrinkled in gerontic specimens; aperture narrow, semicircular or transversely
slitlike, with everted border, oblique to the periphery and with
transverse quadrangular, tape-shaped tooth, sometimes with two fine
angular corners.
Variability. The test shape ranges from nearly circular (Text-fig. 48)
to broadly oval (Text-fig. 49). The shape of the aperture varies from
semicircular to slitlike in specimens, the apertural end of which is
strongly inclined towards the penultimate chamber. The shape of the