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.” } 
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 may 
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 Zhe 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 
