The terminology for Quaternary marine formations of the Mediterranean is in a confused state at present. Although the terms Milazzian and Monastirian have had to be abandoned, shore lines corresponding to these terms exist at numerous places. It is proposed that the general term Tyrrhenian be used for these, and further subdivided into Paleotyrrhenian, Eutyrrhenian, and Neotyrrhenian where more precise dating is possible.