This inventory covers 86 different species of Corallinales (calcareous red algae) that are recorded as having been found in the Mediterranean. Of these, however, 33 species have rarely been observed, or cannot be classified under an accepted name, leaving a discussion of biogeography of 53 species. For each of these 53 species the synonyms are listed and a characterization is given of world distribution and occurrence. Maps are presented of all localities from where these species have been recorded according to a critical assessment of 8043 records originating from 473 references published from 1837 onward. All relevant references are provided in geographically ordered lists. Where considered necessary, additional remarks are also included. New combinations are proposed in Titanoderma and Lithophyllum, while no taxonomic decisions were reached for the names Fosliella ischitana, Goniolithon papillosum and Leptophytum bornetii. In some cases taxon names occur as synonyms under different accepted names, as, amongst others, is the case for Tenarea tortuosa, of which the name can also be found as a synonym under Lithophyllum lichenoides. It is rather odd to perceive that the discussion, which is in fact the biogeographic analysis, has clearly not been made by the same person that composed the inventory. The list of 53 discussed species in this discussion chapter is not exactly corresponding to the floristic list given in the paragraph on materials and methods. Thus Lithophyllum duckeri, Lithophyllum (Goniolithon) rubrum and Leptophytum bornetii occur in the floristic list of reviewed species, but are not incorporated in the table on distribution. On the other hand, however, Goniolithon (Lithophyllum) papillosum, Lithothamnion propontidis and Fosliella ischitana, all listed as “dubiae aut rariter inventae” in the floristic list, are nevertheless included in the discussion on distributions. Lithothamnion minervae, which is printed boldface in the floristic list, is even missing in the index. Another somewhat irritating and unexplained difference between both parts of the book is the uncorrelated division of the Mediterranean in (bio)geographical sectors, resulting in unnecessary complications.