MILIOLIDAE - Acta Palaeontologica Polonica

132 EWA LUCZKOWSKA
are arranged in a sinuous line (Text-fig. 44). The juvenile stage removed
from the inside of an adult specimen does not differ morphologically
from it.
Remarks. - This species differs from Sinuloculina mayeriana (d'Orbigny)
in its more slender test shape, the thickened rim round the
lmm
~@b@),b
~~~,
Fig. 44. Ontogeny and dimorphism of Sinuloculina rixatoria (Franzenau), Upper Tortonian,
W~glinek; I-micro generation, biloculine form with irregularly triloculine
initial part, next chambers arranged in a single plane; 2, 3'- biloculine forms, mega
I generations, pseudotriloculine throughout; a front .view, b aperture view, c crosssection.
aperture and the biloculine arrangement of last chambers: It diffetsfrom
S. cydostoma (Reuss) in the more slender elongated test ahd in its flattening.
It is similar to S. bacillum (Martinotti) from which it however
differs ih the more flattened test, its more expanded middle part, and the
large and circular, not slitlike, aperture.
Distribution. - Poland: Upper Tortonian (W~glinek). Romania: Tortonian,
Buitur.
Genus Triloculina d'Orbigny, 1826, emend. Luczkowska, 1972
Triloculina angularis d'Orbigny, 1850
(PI. XXIII, Fig. 3a, b)
1850. Triloculina angularis d'Orbigny; A. d'Orbigny, p. 409, in Catalogue Ellis &
Messina.