Growth and Development 565 Initiation of Growth 565 Size and Appearance at Hatching 566 Growth of Epidermal Laminae 568 Growth of Juveniles 575 Growth in Later Life 578 Annual Period of Growth 580 Environmental Factors Influencing Growth 580 Number of Growing Years 584 Longevity 585 Weight 586 Bony Shell 586 Color and Markings 593 Wear 595 Sexual Dimorphism 595 Temperature Relationships 598 Optimum Temperature 599 Basking 600 Toleration of Thermal Maxima and Minima 601 Hibernation 611 Diet 617 Populations 623 Movements 626 Locomotion 627 Daily Cycle of Activity 629 Seasonal Cycle of Activity 630 Home Range 632 Homing Behavior 636 Social Relationships 637 Injuries 638 Repair of Injuries to the Shell 641 Ectoparasites 643 Predators 646 Defence 648 Discussion of Adaptations 650 Summary 656 Literature cited 663 INTRODUCTION