THE OCEAN AND THE LAND 201 



abundant, though more varied, and everywhere it decreases 

 in extent and variability with increasing distance from the 

 shores. 



Those curious animals that in our present fauna represent 

 relics persistent from very ancient times are nearly all found 

 in regions where conditions are least variable and approach 

 the optimum, on land in the unchanging tropics, and in the 

 ocean in the colder portions which are free from violent wave 

 action, which means mostly in the deep sea. 



