Treatise on Invertebrate Paleontology
The Treatise on Invertebrate Paleontology (or TIP) published by the Geological Society of America and the University of Kansas Press, is a definitive multi-authored work of some 50 volumes, written by more than 300 paleontologists, and covering every phylum, class, order, family, and genus of fossil and extant (still living) invertebrate animals. The prehistoric invertebrates are described as to their taxonomy, morphology, paleoecology, stratigraphic and paleogeographic range. However, taxa with no fossil record whatsoever have just a very brief listing. Publication of the decades-long "Treatise on Invertebrate Paleontology" is a work-in-progress; and  therefore it is not yet complete: For example, there is no volume yet published regarding the post-Paleozoic era caenogastropods (a molluscan group including the whelk and periwinkle). Furthermore, every so often, previously published volumes of the "Treatise" are revised. Evolution of the project. Raymond C. Moore, the project's founder and first editor, originally envisioned this "Treatise" in invertebrate paleontology as comprising just three large volumes, and totaling only three thousand pages. The project began with work on a few, mostly slim volumes in which a single senior specialist in a distinct field of invertebrate paleozoology would summarize one  particular group. As a result, each publication became a comprehensive compilation of "everything known" at that time for each group. Examples of this stage of the project are "Part G. Bryozoa", by Ray S. Bassler (the first volume, published in 1953), and "Part P. Arthropoda Part 2, the Chelicerata" by Alexander Petrunkevitch (1955/1956). Around 1959 or 1960, as more and larger invertebrate groups were being addressed, the incompleteness of the then-current state of affairs became apparent. So several senior editors of the "Treatise" started major research programs to fill in the evident gaps. Consequently, the succeeding volumes, while still  maintaining the original format, began to change from being a set of single-authored compilations into being major research projects in their own right. Newer volumes had a committee and a chief editor for each volume, with yet other authors and researchers assigned particular sections. Museum collections that had not been previously described were studied; and sometimes new major taxonomic families—and even orders—had to be described. More attention was given to transitional fossils and evolutionary radiation—eventually producing a much-more complete encyclopedia of invertebrate paleontology. But even in the second set of volumes, the various taxa were  still described and organized in a classical Linnaean sense. The more-recent volumes began to introduce phylogenetic 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: