2015-01-082015-01-081977None0078-8554http://hdl.handle.net/10539/16240Main articleA tabulated synthesis of the classification, with geographic and stratigraphic ranges, of the Permo-Triassic tetrapod genera (amphibians, reptiles and mammals) is presented. 657 named genera placed in 161 families are in current use. The degree of stability of these genera and the extent to which they represent a reasonable sample of the preserved remains is considered. A correlation chart of the 148 known faunas has been prepared, on the basis of which a composite zonation scheme is proposed (17 Permian and 20 Triassic zones). The concept of tetrapod "Empires" is introduced. Six successive lowland "Empires" and five concurrent aquatic "Empires" (or provinces) are recognised, recorded and briefly discussed.entetrapod Empires; biostratigraphy; Permian; TriassicArticle