The system of Neogene Mammal Zones, as originally created by Mein (1975), is discussed, and found to be confusing. The Aragonian in the type section and in the surrounding area is discussed, and the evolution of its fauna described in some detail. It appears dubious to apply the MN-zones to the faunules of the Aragonian type area. On the other hand, the type section may well serve as a basis for correlation of Miocene vertebrate localities in Spain and France and — may be — in other parts of Europe.