The Making of Species 



yet this is not the case ; the bulk of the bottom 

 fauna of the coasts are brilliantly coloured animals, 

 and those that show any protective colouring at 

 all appear to be coloured so as to resemble stones 

 or sea-weeds." l 



Before leaving the subject of marine animals, 

 we may point out that the majority of the 

 creatures that live in the everlasting blackness of 

 the depths of the ocean display exceedingly con- 

 spicuous colouring, and this colouring seems to be 

 constant. In such cases the colouring cannot be 

 useful as such to its possessors. The same rnay 

 be said of the colour of blood, or of the colouring 

 of the internal tissues of all organisms. We 

 must not lose sight of the fact that every 

 organism, and every component part thereof, 

 must of necessity be either of some colour or 

 perfectly transparent. It seems to us that since 

 the appearance of The Origin of Species zoologists 

 have tended to exaggerate the importance of 

 colouring to organisms ; they frequently speak 

 of it as though it were the one and only factor in 

 the struggle for existence. It is on this account 

 that they feel it incumbent upon them to find 

 ingenious explanations for every piece of colour- 

 ing displayed by every plant or animal. 



The tendency to exaggerate the importance to 

 an animal of its colouring is doubtless in large 



1 Animal Colouration, p. 125. A book full of valuable facts 

 and ideas on this most interesting subject. 



194 



