Chapter I: Front Matter

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
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
Cretaceous 42
Cenozoic rocks 43
Tertiary 43
Quaternary 43
Main types of fossils 44
Plant fossils 44
Classification of the plant kingdom 44
Division Thallophyta 44
Division Bryophyta 44
Division Tracheophyta 44
Animal fossils 48
Phylum Protozoa 48
Class Sarcodina 48
Order Foraminifera 48
Order Radiolaria 48
Phylum Porifera 49
Phylum Coelenterata 49
Class Anthozoa 49
Subclass Zoantharia 50
Order Rugosa 50
Order Scleractinia 50
Order Tabulata 50
Phylum Bryozoa 50
Phylum Brachiopoda 54
Class Inarticulata 54
Class Articulata 56
Phylum Mollusca 56
Class Gastropoda 59
Class Pelecypoda 59
Class Cephalopoda 66
Subclass Nautiloidea 66
Subclass Ammonoidea 75
Subclass Coleoidea 78
Order Belemnoidea 78
Phylum Annelida 78
Phylum Arthropoda 78
Subphylum Trilobitomorpha 78
Class Trilobita 78
Subphylum Crustacea 80
Class Ostracoda 80
Phylum Echinodermata 80
Subphylum Pelmatozoa 81
Class Cystoidea 81
Class Blastoidea 81
Class Crinoidea 81
Subphylum Eleutherozoa 82
Class Asterozoa 82
Subclass Asteroidea 82
Subclass Ophiuroidea 82
Class Echinozoa 82
Subclass Echinoidea 82
Subclass Holothuroidea 85
Phylum Chordata 85
Subphylum Hemichordata 85
Class Graptolithina 85
Subphylum Vertebrata 86
Superclass Pisces 87
Class Agnatha 87
Class Placodermi 87
Class Chondrichthyes 87
Class Osteichthyes 87
Superclass Tetrapoda 89
Class Amphibia 89
Class Reptilia 89
Cotylosaurs 89
Turtles 89
Pelycosaurs 89
Therapsids 89
Ichthyosaurs 95
Mosasaurs 95
Plesiosaurs 95
Phytosaurs 95
Crocodiles and alligators 95
Pterosaurs 95
Dinosaurs 95
Order Saurischia 97
Suborder Theropoda 97
Suborder Sauropoda 97
Order Ornithischia 97
Suborder Ornithopoda 97
Suborder Stegosauria 97
Suborder Ankylosauria 97
Suborder Ceratopsia 100
Class Aves 100
Class Mammalia 100
Subclass Allotheria 100
Subclass Theria 100
Order Edentata 100
Order Carnivora 102
Order Pantodonta 102
Order Dinocerata 102
Order Proboscidea 102
Order Perissodactyla 104
Horses 104
Titanotheres 104
Chalicotheres 106
Rhinoceroses 106
Order Artiodactyla 106
Entelodonts 106
Camels 106
Books about fossils 108
General works 108
Nontechnical and juvenile 108
Collecting helps 108
Reference works 109
Selected references on Texas fossils 109
Glossary 111
Index 115

Illustrations

Figures— Page
1. Sketch of a coprolite—fossilized animal excrement 14
2. Sketch of a gastrolith—the gizzard stone of an ancient
reptile 14
3. Dendrites—a typical pseudofossil 14
4. Types of symmetry in a fossil coral 24
5. Bilateral symmetry in fossil brachiopod 24
6. A brachiopod showing specimen number and accompanying label 31
7. Two types of micropaleontological slides 32
8. Typical Pennsylvanian crinoidal limestone 41
9. Typical Texas Foraminifera 49
10. Typical radiolarians 49
11. Morphology and principal parts of corals 50
12. Two types of bryozoans 50
13. Morphology and principal parts of articulate brachiopods 54
14. _Lingula_, a typical inarticulate brachiopod 56
15. _Kingena wacoensis_, a common Cretaceous brachiopod 56
16. Morphology and principal parts of gastropod shells 60
17. Morphology and principal parts of a typical pelecypod shell 65
18. Morphology and principal parts of the pearly nautilus 75
19. Characteristic features of the various types of cephalopod
sutures 75
20. Types of typical fossil annelid worms 78
21. Morphology and principal parts of trilobites 80
22. Two extinct attached echinoderms, _Pentremites_ and
_Caryocrinites_ 81
23. Typical modern crinoid, or “sea lily,” showing principal
parts 81
24. Graptolites 86
25. Sketches of mastodon and mammoth teeth 104
26. Two views of a typical fossil horse tooth 104

Plates— Page
1. Geologic time scale Frontispiece
2. Types of fossil preservation 8
3. Silicified brachiopods dissolved from Permian limestones of the
Glass Mountains, Brewster County, Texas 12
4. Dinosaur tracks in limestone in bed of Paluxy Creek near Glen
Rose, Somervell County, Texas 15
5. Fossil collecting equipment 18
6-8. Fossil identification charts 28-30
9. Physiographic map of Texas 36
10. Geologic map of Texas 38-39
11. Geologic range of the major groups of plants and animals 45
12. Fossil plants—thallophytes and tracheophytes 46
13. Fossil plants—tracheophytes 47
14. Paleozoic sponges and sponge spicules 51
15. Pennsylvanian corals 52
16. Cretaceous and Tertiary corals 53
17. Pennsylvanian bryozoans and Cambrian and Mississippian
brachiopods 55
18, 19. Pennsylvanian brachiopods 57, 58
20. Pennsylvanian gastropods 61
21. Pennsylvanian and Cretaceous gastropods 62
22, 23. Tertiary gastropods 63, 64
24. Pennsylvanian pelecypods 67
25-28. Cretaceous pelecypods 68-71
29-31. Tertiary pelecypods 72-74
32. Pennsylvanian and Cretaceous cephalopods 76
33. Cretaceous cephalopods 77
34. Fossil arthropods 79
35. Fossil starfishes, crinoids, and holothurian sclerites 83
36. Cretaceous echinoids 84
37. Primitive armored fish, shark teeth, and conodonts 88
38. Comparison of the dinosaurs 90
39. Comparison of Mesozoic flying and swimming reptiles 91
40. Pelycosaur, cotylosaur, and a primitive amphibian 92
41. Swimming reptiles 93
42. Phytosaur and flying dinosaurs 94
43. Skull of _Phobosuchus_, from Cretaceous of Trans-Pecos Texas
96
44. Saurischian dinosaurs 98
45. Ornithischian dinosaurs 99
46, 47. Cenozoic mammals 101, 103
48. Tertiary mammals 105
49. Cenozoic mammals 107

ERA
PERIOD
EPOCH
CHARACTERISTIC LIFE
CENOZOIC “Recent Life”
QUATERNARY 1 MILLION YEARS
Recent
Pleistocene
TERTIARY 64 MILLION YEARS
Pliocene
Miocene
Oligocene
Eocene
Paleocene
MESOZOIC “Middle Life”
CRETACEOUS 70 MILLION YEARS
JURASSIC 45 MILLION YEARS
TRIASSIC 50 MILLION YEARS
PALEOZOIC “Ancient Life”
PERMIAN 55 MILLION YEARS
CARBONIFEROUS
PENNSYLVANIAN 30 MILLION YEARS
MISSISSIPPIAN 35 MILLION YEARS
DEVONIAN 55 MILLION YEARS
SILURIAN 20 MILLION YEARS
ORDOVICIAN 75 MILLION YEARS
CAMBRIAN 100 MILLION YEARS
PRECAMBRIAN ERAS
PROTEROZOIC ERA
ARCHEOZOIC ERA
APPROXIMATE AGE OF THE EARTH MORE THAN 3 BILLION 300 MILLION YEARS

Texas Fossils
An Amateur Collector’s Handbook

William H. Matthews III[1]