Correlation of the Myachkovian and Kasimovian in the U.S.S.R. with the west European subdivision

The Myachkovian and Kasimovian chronostratigraphic units in the U.S.S.R. are correlated with similar units as used in western Europe. This correlation is here established through northwestern Spain, where fusulinid faunas and plant fossils enable a comparison with the U.S.S.R. and western Europe. It is shown that the lower- and upper limit of the Myachkovian correlate with some level in the Westfalian D and the middle Cantabrian respectively and that the top of the Kasimovian may probably be equated with some level in the Stephanian B.