77 specimens of some species of the genus Pertusaria have been studied by chromatographic and partly also mass spectrometric analyses. P. cyparissi, P. hymenea, P. lecanorodes, P. flavicans, P. flavida, P. rupicola and probably also P. ficorum and P. maximiliana contain the xanthone flavicanon, that causes the yellow colour of the thalli; in P. flavicans, P. rupicola and partly P. flavida and probably also P. ficorum and P. maximiliana the occurrence of the depsidone stictic acid has been shown additionally. The mentioned species are restricted to the mediterranean area respectively have extended from there to Western and Central Europe, the sorediate ones widest to the north-east respectively to the alpine zone. It is discussed, whether in spite of their differences in the structure of the apothecial verrucae, these species represent a systematic unit. The substances may be used partly to characterize the species. P. coronata is distinguished chemically from P. coccodes, to which it is placed recently, by an unidentified substance orange fluorescing in ultra-violet light, and further by stictic acid instead of norstictic acid. Both the species are not related to P. hymenea. The distribution of the species of the P. hymenea- group in Europe has been mapped out roughly.