Several poorly known, mainly suboceanic species of Bacidia slat. mostly from Poland are presented based on recent field studies or revisions of Polish collections. Bacidia caligans proves to be new for the Polish Carpathians, Bacidia delicata, new for the Czech Republic, Bacidia hemipolia for Poland and the Czech Republic, Bacidia saxenii for Poland and the whole Carpathians, and Bacidia viridescens new for Poland. Bacidia circumspecta is new for the whole Polish lowland. Detailed world distributions for more species are included. A new forma, Bacidia hemipolia f. pallida Czarnota & Coppins from Central Europe, is described and illustrated.