Thin sections of the Salem Limestone from outcrops in the Mississippi River bluffs in southwestern Illinois contain tiny, calcareous spheres which are prominent elements in certain types of limestone. These microorganisms are referable to the genus Calcisphaera established by Williamson (1880). They vary in size, having diameters of 30 to 165 microns. They occur most abundantly in calcisiltites and calcarenites in which microcrystalline, nonskeletal grains are important rock forming elements. They also occur in calcilutite.
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.
SEPM (Society for Sedimentary Geology) is an international not-for-profit Society headquartered in Tulsa, Oklahoma. Through its network of international members, the Society is dedicated to the dissemination of scientific information on sedimentology, stratigraphy, paleontology, environmental sciences, marine geology, hydrogeology, and many additional related specialties. The Society supports members in their professional objectives by publication of two major scientific journals, the Journal of Sedimentary Research and PALAIOS. Additionally, SEPM produces technical research conferences, short courses, and Special Publications. Through SEPM's Continuing Education, Publications, Meetings, and other programs, members both gain and exchange information pertinent to their geologic specialties.
This item is part of a JSTOR Collection.
For terms and use, please refer to our
Journal of Paleontology
© 1960 SEPM Society for Sedimentary Geology