MILIOLIDAE - Acta Palaeontologica Polonica

88 EWA LUCZKOWSKA
circular, flush with the periphery and with a short quadrate, slightly bifid
tooth.
Variability. The test shape is variable, being nearly circular or oval
(Text-fig. 31). The ribs are more or less regular, beginning mostly at the
lmm
Fig. 31. Morphological variability of Cycloforina toreuma (Serova), Lower Sarmatian,
Zrecze-3 borehole, depth 64.8-64.9 m; specimens arranged according to the size of
the test; a front view, b apertural view.
base of chambers and disappearing towards the end. The tooth shape may
be small and narrow to broad and bifid.
Dimorphism and ontogeny. The specimens sectioned are t~e micro
generation; PD 30 fl. The sections show that all the chambers have a subtriangular
outline and flattened sides throughout and increase gradually
in size (Text-fig. 29/2).
Remarks. - This species differs from Cyclojorina karreri ovata (Serova)
in having irregular ribs placed on the periphery of chambers only
and in the more flattened sides of chambers. From Varidentella pseudocostata
(Venglinsky) it differs in the circular shape of the aperture,
narrower tooth, smaller test dimensions, flattened sides of chambers, and
more distinct ribs.
Distribution. - Poland: Lower Sarmatian, (Rytwiany, Zrecze). USSR:
Upper Tortonian, Volhyn-Podolian Platform, West Ukraine.
+ Cyclojorina vermicularis (Karrer, 1868)
(PI. XIII, Fig. lOa-c; Text-fig. 32)
1868. Quinqueloculina vermicularis Karrer; F. Karrer, p. 150, PI. 3, Fig. 1.
Material. - About 500 specimens (ColI. No. F-140, Sec. No. 35-44).
Dimensions: L 0.65-1.5; B 0.47-1.0; T 0.3-0.7.