132 THE OCEAN 



great importance, but in reality it is a most 

 wise provision of nature and prevents the 

 wholesale destruction of these little creatures, 

 many of which are the young forms of animals 

 that in later life are very valuable to man. If 

 these surface creatures were opaque, or bright- 

 ly-coloured, they would easily be seen by fishes 

 and other hungry animals swimming below 

 the surface and would be plainly visible 

 to sea-birds hovering above the waves. Their 

 transparency, however, protects them from 

 these numerous enemies until, in later life, 

 they assume other forms, colours and habits 

 and are better able to look after their own 

 safety. 



Even as it is vast numbers are devoured and 

 only a very small percentage ever reach full 

 size. In the same way, if we study the crea- 

 tures in shallow water, or even at great depths, 

 we will find, when once we know their habits, 

 that their strange forms and peculiar colours 

 serve equally useful purposes. The bril- 

 liantly-tinted and conspicuous things are usu- 

 ally poisonous or possess stings and thus warn 

 other creatures of the danger of attacking 



