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Pelecypods from the Upper Eocene of East Poland

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The pelecypod assemblage from Upper Eocene sandy deposits of the vicinity of Siemień and Luszawa (eastern part of the Polish Lowlands) consists of 23 species. The majority of the species are typical of the Bartonian.
Encrusting foraminiferans, although representing an important component of the so−called cryptic assemblages in both modern and ancient reef environments, are in general poorly described and little is known as regards their association with corals.In this paper, we describe coral−encrusting foraminiferan associations in the different facies that characterize the shallowing upward parasequences of the Nago Limestone (Upper Eocene, Trentino, northern Italy).From a relatively deep reef slope up to the shallow shelf−edge, corals have been recognized to be encrusted by different types of foraminiferan assemblages that differ on the basis of relative abundance of species, growth form and type of encrusted coral surface.The succession of encrusting foraminiferan assemblages is interpreted as controlled mainly by light, competition with coralline algae, hydrodynamic energy, and coral growth fabric.
Foraminiferal assemblage found in Upper Eocene deposits from Siemień (Eastern Poland) includes over 70 species. This assemblage lived in cold shelf waters 80-100 m deep. The foraminifera-bearing deposits may be correlated with lower part of marls of Kiev stage from Ukraine, representing the lower horizon of the Upper Eocene and/or the Middle-Upper Eocene junction beds. Foraminiferal assemblage from Siemień beds is entirely different from that known from the stratotype of the Bartonian. Marine transgression responsible for deposition of Siemień beds presumably reached the area of Poland from the East, utilizing old tectonic frame: Dnepr-Donetz aulacogen and its extensions. This is confirmed by a marked similarity of foraminiferal assemblages as well as composition of heavy minerals present in deposits of Siemień beds.
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Ostracods from the Upper Eocene of East Poland

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Ostracods of the Upper Éocène epicontinental deposits of east Poland are described. Of the 40 species, referred to 32 genera, Flexus erikae and Pterygocythereis siemienensis are the new ones. Age, palaeogeography and palaeoecology of the studied assemblage are discussed.
Dome−shaped cheilostome bryozoan colonies, most commonly about 2 cm in diameter, are common in Upper Eocene offshore deposits of southeastern North Carolina, USA.This colony−form is anachronistic in the Eocene, being more typical of Palaeozoic bryozoans.There are three types of domes: individual colonies of Parasmittina collum (Canu and Bassler), individual colonies of Osthimosia glomerata (Gabb and Horn) and multispecies intergrowths.The bryozoans grew laterally beyond initial shell substrata to become free−lying. P. collum colonies grew by local eruptive budding, forming subcolonies that extended radially over the underlying layer of zooids.Undersides of subcolonies that extended beyond the original substratum have basal exterior walls that are more commonly fouled by encrusters than is the upper side of the colony.By contrast, lateral growth of O. glomerata colonies was limited by size of the original substratum, subcolonies were not developed, and colony growth occurred by prolific frontal budding over the entire upper surface of the colony. Undersides of colonies beyond the substratum consist of the lateral interior walls of marginal zooids and are much less commonly fouled than are undersurfaces of P. collum.The upper surfaces of multispecies domes by definition are always fouled, and their undersurfaces are also commonly fouled.
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