and cladistic ideas, along with new developments and discoveries in fields such as biogeography, molecular phylogeny, paleobiology, and organic chemistry, so that the current edition of Brachiopoda (1997 to 2002) is classified according to a cladistic arrangement, with three subphyla and a large number of classes replacing the original two classes of Articulata and Inarticulata. All these discoveries led to revisions and additional volumes. Even those taxa already covered were expanded: Books such as those regarding the Cnidaria (vol. F), the Brachiopoda (vol. H) and the Trilobita (vol. O) each went from one modest publication to three large volumes. And yet another volume regarding the brachiopods (number five) was published in 2006. Until 2007, the editor of the Treatise was Roger L. Kaesler at The Paleontological Institute at the University of Kansas in Lawrence, Kansas. Layout of the articles From the beginning, the character of the Treatise volumes has followed and further developed the pattern of the classic Invertebrate Paleontology written by Moore, Lalicker and Fischer (1953). Following their lead, the Treatise includes in a typical article (a) a description of the basic anatomy of the modern members of each invertebrate group, (b) distinctive features of the fossils, (c) a comprehensive illustrated glossary of terms, (d) a short discussion of the evolutionary history of the group, (e) a stratigraphic range chart, done at the level of the major subdivision (lower, middle and upper) of each Geologic period. This is followed by (f) a listing and technical description of every known genus, along with (g) geographic distribution (usually by continent only, but occasionally by country) and (h) stratigraphic range. Next come (i) one or two representative species illustrated by line drawings (in the early volumes) or by black-and-white photographs (in subsequent volumes), each accompanied by an appropriate reference for that genus. Furthermore, each Treatise article includes (j) the date, authorship, and scientific history of the taxa. Finally, there is (k) a comprehensive bibliography and list of references. Not only that, but the more recent volumes and revisions also include (l) new fossil and phylogenetic discoveries, (m) advances in numerical and cladistic methods, (n) analysis of the group's genome, (o) its molecular phylogeny, and so on. List of its volumes The following is an annotated list of the volumes already published (1953 to 2007) or volumes currently being prepared: Introduction (A) and sub-metazoan Protista (B, C & D) Part A. Introduction: Fossilization