《PLANT LIFE THROUGH THE AGES》

Chapter ⅠINTRODUCTORY1

Chapter ⅡTHE CRUST OF THE EARTH5

Geological Table10

The Age of the Earth12

The Grand Canyon of Arizona14

Ingleborough, West Yorkshire17

The North West Highlands of Scotland18

Chapter ⅢGEOLOGICAL CYCLES21

Geological Revolutions21

The Building of the Alps28

Chapter ⅣOTHER ASPECTS OF GEOLOGICAL HISTORY83

Ice Ages33

The Wegener Hypothesis41

Chapter ⅤPRESERVATION OF PLANTS AS FOSSILS45

The Interpretation of Records of Ancient Plants55

Chapter ⅥA CLASSIFICATION OF PLANTS60

Chapter ⅦTHE EARLIEST RECORDS OF PLANT-LIFE: THE PRE-CAMBRIAN ERA74

The Origin of Life75

Problematical and Organic Pre-Cambrian Remains79

Algae as Rock-builders80

The Interpretation of certain Rock-Structures: Organic or Inorganic？88

Chapter ⅧPAGE THE EARLIER PALAEOZOIC SEAS. THE CAM-BRIAN, ORDOVICIAN AND SILURIAN PERIODS93

The Cambrian Period93

The Ordovician Period94

The Silurian Period96

The Earliest Traces of Terrestrial Plants98

Algae: Living and Extinct101

Remains of Higher Plants109

Chapter ⅨA LAND VEGETATION: THE DEVONIAN PERIOD111

Marine Devonian and Continental Old Red Sandstone Rocks111

A. THE EARLIER DEVONIAN FLORAS117

The Psilophytales121

Higher Plants125

Plants from a Devonian Marsh126

Other Devonian Plants134

B. THE LATER DEVONIAN FLORAS139

Forest Trees142

Pteridosperms and Ferns144

Other Late Devonian Plants148

TABLE A. GEOLOGICAL AND GEOGRAPHICAL DISTRIBUTION OF DEVONIAN PLANTS152

Chapter ⅩTHE CARBONIFEROUS AND PERMIAN PERIODS155

Carboniferous and Permian Rocks: the Geological Back- ground155

The Coal Measures162

The Permian Period164

India and the Southern Hemisphere: Gondwanaland167

Australia170

India176

South Africa and South America177

Chapter Ⅺ THE EARLIER CARBONIFEROUS VEGETATION180

Calcareous, Reef-building Algae182

Lycopodiales183

Articulatae188

Pteridosperms189

Ferns193

Psygmophyllum and Pitys201

Chapter Ⅻ THE LATER CARBONIFEROUS VEGETATION203

with some account of Permian floras203

A Scene in the Coal Age203

The Lower Plants207

Pteridosperms213

An Anatomical Comparison of Palaeozoic and other Stems218

Articulate Plants: Calamites and others221

Lycopodiales224

Gymnosperms: Conifers, Cycadophytes, Ginkgoales, etc225

Ferns230

Botanical Provinces: Floras234

A Far Eastern Flora235

The Glossopteris Flora242

The Kusnezk Flora248

A Permian Flora in Arizona249

Climate253

The Climate of Gondwanaland258

Geological Distribution of Carboniferous and Permian Plants258

TABLE B. THE GEOLOGICAL AND GEOGRAPHICAL DISTRIBU- TION OF SOME CARBONIFEROUS AND PERMIAN PLANTS266

The Transition from one Era to another279

The Geographical Distribution of Carboniferous and Permian Plants281

Notes on Literature (Carboniferous and Permian)287

Chapter ⅩⅢ THE FIRST PHASE OF THE MESOZOIC ERA: THE TRIASSIC PERIOD289

A New Era289

Triassic Rocks292

Triassic Algae295

An Early Triassic Scene299

A. THE EARLIER TRIASSIC VEGETATION301

Equisetales301

Lycopodiales302

Ferns303

Cycads and Conifers304

B. THE LATER TRIASSIC AND THE RHAETIC FLORAS306

Rhaetic Greenland307

Equisetales, Lycopods, and Ferns311

Fern-like Plants which are probably Pteridosperms314

Cycadophyta; Ginkgoales, etc317

Rhexoxylon, a Triassic Stem with the Structural Features of a Modern Lians321

Links with the Palaeozoic Era323

The Vegetation of Gondwanaland324

Between Two Eras: Connecting Links328

TABLE C. GEOLOGICAL AND GEOGRAPHICAL DISTRIBUTION OF SOME TRIASSIC AND RHAETIC PLANTS332

Chapter ⅩⅣ THE JURASSIC PERIOD335

Jurassic Rocks335

The Jurassic Plant-world341

TABLE D. GEOLOGICAL AND GEOGRAPHICAL DISTRIBUTION OF SOME JURASSIC PLANTS343

Equisetales345

Lycopods and Ferns345

A Dominant Group: the Cycadophyta352

Williamsoniella: Williamsonia353

Cycadeoidea356

Ginkgoales: Conifers362

Possible Representatives of the Pteridospermeae: Jurassic Angiosperms365

A Jurassic Flora from the borders of Antarctica368

TABLE E. THE GEOGRAPHICAL DISTRIBUTION OF JURASSIC PLANTS FROM GRAHAM LAND369

Chapter ⅩⅤ THE CRETACEOUS PERIOD378

Cretaceous Rocks378

The Dawn of a New Era383

An Early Cretaceous (Wealden) Flora385

Cretaceous Charophyta and Algae388

An Arctic, Cretaceous Flora389

Other Cretaceous Plants393

Ferns394

Ginkgoales: Cycadophyta395

Conifers396

Flowering Plants397

Various Cretaceous Floras.The Potomac Floras of Eastern North America400

Other American Floras401

Cretaceous Floras in other parts of the World402

Cretaceous Flowering Plants403

Cretaceous Floras of the Southern Hemisphere406

TABLE F. THE GEOLOGICAL AND GEOGRAPHICAL DISTRIBUTION OF SOME CRETACEOUS PLANTS413

Chapter ⅩⅥ THE CAINOZOIC ERA: THE TERTIARY PERIOD415

Tertiary Rocks415

Tertiary Algae420

Fungi426

General features of the Tertiary Period Vegetation427

Fossil Plants as Evidence of Climate429

EOCENE FLORAS432

Ferns433

Conifers435

Ginkgoales: Cycadophyta440

Flowering Plants440

OLIGOCENE AND MIOCENE FLORAS450

An Oligocene River-estuary in the Isle of Wight450

Other Floras: the Wanderings of Tertiary Plants453

PLIOCENE FLORAS456

French Pliocene Floras459

Pliocene Plants from the Old Delta of the Rhine, etc460

TERTIARY FLORAS IN THE SOUTHERN HEMISPHERE463

TABLE OF TERTIARY FLORAS IN THE NORTHERN HEMISPHERE AND IN THE SOUTHERN HEMISPHERE465

TABLE G. GEOGRAPHICAL DISTRIBUTION OF SOME TERTIARY PLANTS471

Chapter ⅩⅦ THE QUATERNARY PERIOD480

A. THE GLACIAL PERIOD481

Interglacial Periods486

Tundra and Steppe Conditions488

An English Landscape in the latter part of the Glacial Period492

The effect of the Glacial Conditions on the Vegetation494

B. THE POST-GLACIAL STAGE501

Plant-records from Peat502

History of the Vegetation of the Southern Pennines (York- shire)507

Interglacial Periods508

The History of Vegetation during the last Interglacial Period in Jutland and North-west Germany509

The period of Submerged Forests, and later510

Chapter ⅩⅧ CONCLUSION514

The History of the Plant-World515

The Evolution of the Flowering Plants: an unsolved problem520

Persistence, Progression, and Retrogression through the Ages523

Architectural Types in Plant-stems526

Arctic Floras of the Past531

Climates of the Past534

BIBLIOGRAPHY545

INDEX587