For students of marine Silurian megafossils there are globally two major sites for superlative specimens: the island of Gotland for the latest Llandovery–very Late Silurian, and the island of Anticosti for the earliest Llandovery into the latest Llandovery. The new treatment of the orthide brachiopods in this Special Paper substantially helps to update our understanding of the group's Llandovery record. The Special Paper is well written, provided with excellent illustrations and a text that carefully describes the taxa involved. Also provided is a brief account of the Anticosti litho- and biostratigraphy, together with a brief history of prior palaeontological investigations of Anticosti fossils, chiefly brachiopods. A detailed locality Appendix is a valuable adjunct for specialists, together with a warning (p. 11) about locality name changes during the past 150 years of publication on the fossils.

Variation was studied relative to length and width of the abundant taxa, but other characters remain to be considered. For those taxa represented by a good size range of specimens a study of their ontogeny, particularly internal features, remains to be carried out. For some taxa there is a need for further investigation of internal features by calcining shells followed by careful shaving away of the calcined material to reveal internal features preserved on the moulds.