the upper stage of the Lower Devonian system (period). At its type location, the Emsian is represented by a thick layer of sandstones, clays, and shales. Two substages have been identified in the Ardennes-Rhine region. The upper substage is characterized by a change in the marine fauna and the appearance of Middle Devonian groups, such as brachiopods, trilo-bites (Basidechenella), goniatites (Anarcestes), and corals (Calceolo sandalina).
The Emsian Stage corresponds to the upper part of the Co-blenzian Stage in Belgium. In the USSR it corresponds approximately to the upper part of the Lower Devonian and the lower part of the Eifelian Stage. [SeeDEVONIAN SYSTEM (PERIOD).]