ILLUSTRATIONS 



The giant bald cypress of Santa Maria del Tule Frontispiece 



Fig. 1. Map showing the early Upper Cretaceous geography of North 



America 18 



Fig. 2. Map showing the later Cretaceous history of North America. . 20 

 Fig. 3. Map of the maximum extent of Eocene seas in North America. . 22 



Fig. 4. Map showing Oligocene conditions in North America 24 



Fig. 5. A cone-bearing twig of the big tree 40 



Fig. 6. A cone-bearing twig of the modern redwood 44 



Fig. 7. A cone-bearing twig of a widespread Cretaceous big tree 49 



Fig. 8. A cone-bearing branch of a common Miocene sequoia 50 



Fig. 9. Map of the world showing the present and past distribution of the 



sequoias and their probable paths of dispersal 54 



Fig. 10. Map of the world showing the present and past distribution of the 



bald cypress 62 



Fig. 11. Map of southeastern North America showing the present and 



Pleistocene range of the bald cypress 66 



Fig. 12. Map of the world showing the present and former distribution of 



the hickories 70 



Fig. 13. Map of the world showing the present and past distribution of the 



walnuts 74 



Fig. 14. ]\Iap showing the present and past distribution of the other mem- 

 bers of the walnut family 76 



Fig. 15. The winged fruit of a tropical upland member of the walnut family. 77 



Fig. 16. Some fossil leaves and nuts of the walnut 79 



Fig. 17. Map of Europe showing the limits of glaciation and the Pleistocene 



occurrences of the Arctic willow 87 



Fig. 18. Some fossil forms of willows and poplars 93 



Fig. 19. Map of the world showing the range of the modern birches and 



localities where fossil forms have been found 99 



Fig. 20. Map of the world showing the existing range and fossil occur- 

 rences of the hazel 104 



Fig. 21. Map of the world showing the existing range and fossil occurrences 



of the hornbeam 108 



Fig. 22. Map of the world showing the existing range and fossil occurrences 



of the ironwood HI 



Fig. 23. ]\Iap of the world showing the existing range and fossil occurrences 



of the alder 113 



