EXTINCTION OF THE SAURIANS. 439 



existence. Fancy a crocodile twenty-seven feet long, with the 

 fins of a whale, the long and flexible neck of a swan, and a 

 comparatively small head. With the appearance of this new 

 tyrant, the last hope of escape is taken from the trembling 

 fishes; for into the shallow waters, inaccessible to the more 

 bulky Ichthyosaurus, the slender Plesiosaurus penetrates with 

 ease. 



A race of such colossal powers seemed destined for an immor- 

 tal reign, for where was the visible enemy that could put an end 

 to its tyranny ? But even the giant strength of the saurians 

 was obliged to succumb to the still more formidable power of 

 all-changing time, which slowly but surely modified the circum- 

 stances under which they were called into being, and gave birth 

 to higher and more beautiful forms. 



In the tertiary period, the dreadful reptiles of the mesozoic 

 seas have long since vanished from the bosom of the ocean, and 

 cetaceans, walruses, and seals, unknown in the primitive deep, 

 now wander through the waters or bask on the sunny cliffs. 

 With. them begins a new era in the life of the sea. Hitherto it 

 has only brought forth creatures of base or brutal instinct, but 

 now the Divine spark of parental affection begins to ennoble its 

 more perfect inhabitants, and to point out the dim outlines of 

 the spiritual world. 



During all these successive changes the surface of the earth 

 has gradually cooled to its present temperature, and many 

 plants and animals that formerly enjoyed the widest range must 

 now rest satisfied with narrower limits. The sea-animals of the 

 north find themselves for ever severed from their brethren of 

 the south, by the impassable zone of the tropical ocean ; and 

 all the fishes, molluscs, and zoophytes, whose organisation 

 requires a greater warmth, confine themselves to the equatorial 

 regions. 



As the tertiary period advances towards the present epoch, 

 the species which flourished in its prime become extinct, like the 

 numberless races which preceded them ; new modifications of 

 life, more and more similar to those of the present day, start 

 into existence ; and, finally, creation appears with increasing 

 beauty in her present rich attire. 



Thus old Ocean, after having devoured so many of his chil- 

 dren, has transformed himself at last into our contemporaneous 



