This paper discusses the complexity of the determination and taxonomy of Palaeogene fossil floras from Slovenia (village of Socka, north of Celje; Sava folds in Central Slovenia) and Croatia (Central Dalmatia – Mt Promina). One of the most important problems presented by the determination of individual species of fossil leaves is connected with the complex classification (species, genus and family) of traditional determinations of architecture and leaf morphology and also of cuticular studies. In this case, the problems are related to the determination of some fossil leaves and the morphological similarities inside some families, genera or species and among some families. This is related to conifers (Cupressaceae, Taxodiaceae, Araucariaceae), laurels (similarities among themselves and between some families), the families Myricaceae, Moraceae, Rhamnaceae, Proteaceae, Sapotaceae and »Leguminosae« type of leaves. In spite of these problems general palaeobotanical conclusions are very close to composition of classic Palaeogene palaeo-phytoassociations.Članak ističe složenost determiniranja i taksonomsku problematiku uzoraka fosilne makroflore iz Socke i Posavskih bora (Slovenija) i šire okoline planine Promine (Hrvatska). Posebice je izražena problematika određivanja pojedinačnih uzoraka i njihovo pravilno svrstavanje (vrsta, rod, porodica), no unatoč svemu ne remeti se zaključak o ukupnom sastavu i karakteru fosilnih biljnih zajednica toga doba. Ovdje se ističe problematika određivanja pojedinih vrsta i njihove međusobne morfološke sličnosti, kako unutar samih porodica, rodova i vrsta, tako i između pojedinih vrsta. To se odnosi na fosilne četinjače (Cupressaceae, Taxodiaceae, Araucariaceae), lovore (međusobne sličnosti i sličnosti pojedinim drugim porodicama), porodice Myricaceae, Moraceae, Rhamnaceae, Proteaceae, Sapotaceae i lišće tzv. »leguminoznoga tipa«
