130 THE HAUNTS OF LIFE 
esses that go on in the body. [If this is so, they 
have their counterpart in the brilliant colours 
of the withering leaves in autumn. For these 
colours, as colours, are of no use to the trees. 
BIG EYES AND LITTLE EYES 
Another puzzle of the deep sea is the occur- 
rence of fishes with big eyes and of others with 
little eyes. If the fishes were all small-eyed 
or approaching blindness, it would be easy to 
say that in a world of darkness they were 
gradually losing their sight, for we know that 
gold-fishes kept in absolute darkness for three 
years become blind, actually losing the per- 
ceiving elements called rods and cones in the 
retina of the eye. But what is to be made of 
the occurrence of big-eyed and small-eyed 
fishes in the same conditions? Perhaps it 
might be said that the small-eyed forms have 
been longest in the abysses, and therefore show 
greater degeneration of the eye. But this 
cannot be the whole answer, for in many cases 
the eyes are unnaturally large—so large that 
they occupy about a fifth of each side of the 
head. Sometimes they have become what are 
called telescope-eyes, projecting far forward 
