CONTENTS. xxv 



PAGE 



Australia 632 



India. 634 



South Africa 635 



South America 638 



Close of the Paleozoic Era 639 



The Life of the Permian 641 



The impoverishment of life, 641. 



I. The Plant Life 642 



Change in the flora, 642. The Glossopteris flora, 646. 



II. The Land Animals 646 



The Amphibians, 646. The appearance of the primitive 

 reptiles, 647. The more distinctively reptilian group (Diap- 

 sida), 649. The mammalian strain of the reptilian group 

 (Synapsida), 649. The scant record of other land forms, 652. 



III. The Fresh-water Life 652 



IV. The Marine Fauna 652 



The advent of the ammonites, 653. The retreatal tracts 

 of the marine life, 655. 



The Problems of the Permian 655 



I. The Deformation 656 



II. The Immediate Sequences of the Deformation 658 



Interference with circulation, 658. Topographic sequences, 

 659. 

 III. The More Remote Sequences of the Deformation 660 



Effects on the constitution of the atmosphere and hydro- 

 sphere, 660. The atmosphere and hydrosphere in the Mis- 

 sissippian and Carboniferous periods, 660. The part played 

 by limestone formation, 660. The part played by coal 

 formation, 664. The enrichment of the air in oxygen, 665. 

 The relations of equilibrium between the carbon dioxide of 

 the air and that of the ocean, 665. The influence of the 

 rate of diffusion, 666. The influence of agitation and cir- 

 culation, 667. The influence of temperature, 667. The influ- 

 ence of secular temperature changes, 668. Interruption of 

 the water-heating system, 669. Extension of continental 

 climates, 669. Reduction of humidity, 669. Depletion of 

 the heat-absorbing constituents of the atmosphere, 669. 

 The vicarious action of carbon dioxide, 670. The thermal 

 functions of the atmospheric constituents, 670. The time of 

 retention, 672. Primary independence in selective action, 

 673. Thermal transference by molecular contact, 673. 



