The recently proposed subclass Euomphalomorpha Bandel and Fryda, 1998 was primarily based on an openly coiled, planispiral initial whorl. Here, the protoconch of Carboniferous euomphalids is described and figured in detail ...

We have analyzed the stable carbon isotope ratios of various organic-walled microfossils preserved in marine sediments of Silurian and Devonian age. The aim of this study is to determine the amplitude of isotopic fractionations ...