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Pennsylvanian
Fossils of North Texas
Occasional Papers Volume 6 of the Dallas Paleontological Society Copyright 2003 Mark McKenzie and John McLeod ISBN 0-9714271-2-7 First printing March 2003 145 pages, extensive black
and white photographs
Order from the authors' web
site,
www.pennfossils.com or the
Dallas
Paleontological Society .
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This guidebook's look at several interesting North Texas localities is a welcome addition to current Texas fossil publications that often focus primarily on our famous Cretaceous vertebrate and invertebrate fauna. As the authors note, north Texas outcrops represent some of the most fossiliferous marine shelf sediments in the United States. The introduction sets the stage with a clear picture of the geology and paleoenvironments that existed during deposition of the Canyon and Virgilian groups. The discussion of fossil classification explains the rationale for genus-level identification used in the book. The Lake Bridgeport Shale in Wise County is extensively examined in two chapters, one for the molluscan biofacies and the other for the sponge-echinoderm biofacies. Many illustrated specimens were collected during the drought of 1997-2000 that lowered the lake level to just above 600 feet. Nodules containing fossils concentrate as float on the shore; many of the specimens show beautiful preservation as a result of being enclosed in the nodules. Chapter 4 is devoted to the Finis Shale exposed at the spillway of the Lost Creek Reservoir portion of Lake Jacksboro in Jack County. The illustrated fauna from this fossiliferous core shale concentrates on less common specimens such as the tabulate coral Paleacis, the rostroconch Apotocardium, fourteen nautiloid and fifteen goniatite cephalopod genera. Chapter 5, Late Pennsylvanian Marine Sharks of Texas, assembles a comprehensive guide to shark fossils from the Finis Shale/Lake Jacksboro spillway and the Saddle Creek Limestone from the Wilson Clay Pit in Coleman County. In addition to photographs and descriptive information on teeth, denticles, spines, skulls and coprolite, the authors provide a helpful discussion of the identification problems associated with variation in shark tooth morphology. The book's narrowed focus on selected fauna from a few localities and wealth of material on crinoids, cephalopods and sharks sets it apart from general field guides available today. It will be a welcome addition to the bookshelf (and backpack) of all who appreciate the Pennsylvanian fossils of North Texas. --- J. Slamen,
HGMS Paleo Section member
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