The Somerset Shale Member (Mississippian: Valmeyeran) is a discontinuous shale at the base of the Salem Limestone in southern Indiana and central Kentucky. It is the only significant terrigenous unit within a thick sequence of shoaling carbonates deposited on the eastern side of the Illinois Basin over the Borden Delta siltstones. The Somerset Shale contains a diverse echinoderm fauna of blastoids (five species), crinoids (20 species), and echinoids (two species). Most of the species are known only from the Somerset or from carbonate rocks directly above and below the Somerset Shale. There remains a small number of species previously known mostly from terrigenous rocks (the Borden Delta) below the carbonates. This demonstrates that at least some of the faunal differences between the Borden crinoids and those of the overlying carbonates are the result of paleoecologic factors. The Somerset Shale may mark a useful biostratigraphic boundary defined by last occurrences of the genera Barycrinus, Cyathocrinites, and Actinocrinites and the base of the range of Batocrinus. The species Batocrinus somersetensis n. sp., Dizygocrinus calvus n. sp., and Barycrinus punctus n. sp. are described.
The Journal of Paleontology, published by the Paleontological Society, includes original articles and notes on the systematics of fossil organisms and the implications of systematics to biostratigraphy, paleoecology, paleogeography, and evolution. The Journal emphasizes specimen-based research and features high quality illustrations. All taxonomic groups are treated, including invertebrates, microfossils, plants, and vertebrates. The Journal seeks to appeal to a broad international audience, and to publish comprehensive systematic treatments of taxa, which employ modern analytical techniques and have broad evolutionary, environmental, and/or geographic significance. The Journal also publishes review articles, opinion pieces in its "View From the Field" section, comments and replies in response to recent publications in the Journal, and book reviews.
The Paleontological Society is an international organization devoted exclusively to the advancement of the science of paleontology. The Society was founded in 1908 in Baltimore, Maryland, and has ~1,500 members, including professional paleontologists, academicians, explorationists, science editors, earth-science teachers, museum specialists, land managers, students, amateurs, and hobbyists. The Society holds an Annual Meeting, which is ordinarily in the fall at the same time and place as the Annual Meeting of The Geological Society of America (GSA). The Paleontological Society publishes the Journal of Paleontology six times annually, as well as Paleobiology, which is released quarterly. The Society also publishes, on an irregular basis, The Paleontological Society Memoirs (issued as supplements to the Journal), Short Course Notes, and Special Publications. The Society's official newsletter, Priscum, is issued to all members twice yearly.
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