BUREAU OF ECONOMIC GEOLOGY The University of Texas at Austin Austin, Texas 78712 John T. Lonsdale, Director Guidebook 2 TEXAS FOSSILS: _An Amateur Collector’s Handbook_ By William H. Matthews III November 1960 _Second Printing, July 1963_ _Third Printing, August 1967_ _Fourth Printing, June 1971_ _Fifth Printing, November 1973_ _Sixth Printing, April 1976_ _Seventh Printing, November 1978_ _Eighth Printing, September 1981_ _Ninth Printing, August 1984_ Contents Page Introduction 1 What are fossils? 3 The study of fossils 4 Paleobotany 4 Invertebrate paleontology 4 Vertebrate paleontology 4 Micropaleontology 4 Preservation of fossils 5 Requirements of fossilization 5 Missing pages in the record 5 Different kinds of fossil preservation 7 Original soft parts of organisms 7 Original hard parts of organisms 7 Calcareous remains 10 Phosphatic remains 10 Siliceous remains 10 Chitinous remains 10 Altered hard parts of organisms 10 Carbonization 10 Petrifaction or permineralization 10 Replacement or mineralization 10 Replacement by calcareous material 11 Replacement by siliceous material 11 Replacement by iron compounds 11 Traces of organisms 11 Molds and casts 11 Tracks, trails, and burrows 14 Coprolites 14 Gastroliths 14