Pseudofossils 14 Dendrites 14 Slickensides 16 Concretions 16 Where and how to collect fossils 17 Collecting equipment 17 Where to look 19 How to collect 20 Cleaning and preparation of fossils 21 How fossils are named 21 The science of classification 21 The units of classification 22 Identification of fossils 23 Use of identification keys 23 Identification key to main types of invertebrate fossils 26 List of Texas colleges offering geology courses 27 Cataloging the collection 31 How fossils are used 31 Geologic history 33 Geologic column and time scale 33 The geology of Texas 34 Physiography 35 Trans-Pecos region 35 Texas Plains 35 High Plains 35 North-central Plains 37 Edwards Plateau 37 Grand Prairie 37 Llano uplift 37 Gulf Coastal Plain 37 Geology 37 Precambrian rocks 40 Paleozoic rocks 40 Cambrian 40 Ordovician 40 Silurian 40 Devonian 40 Mississippian 41 Pennsylvanian 41 Permian 41 Mesozoic rocks 42 Triassic 42 Jurassic 42