In Volume 6 no less than 167 species are treated and depicted, of which 3 are described as new. Two important families are covered: the Schizochitonidae and the Chitonidae. Especially the coverage of the Chitonidae, with well know and species-rich genera and subgenera as Chiton, Rhyssoplax, Acanthopleura, Tonicia, Lucilina and Onithochiton is long awaited and will prove very useful to researchers, students and collectors alike.