52 THE HAUNTS OF LIFE 



violet, brown, and green, and it is often 

 almost perfectly self-camouflaged among 

 brightly coloured seaweeds. 



Not less subtle is the rapid change of 

 colouring and pattern in flat fishes like plaice 

 and dab. Very quickly they put on the hue 

 and the marking of the sand or shingle on 

 -which they are resting. When on sand they 

 usually cover themselves quickly, all except 

 the eyes which protrude and look about. 

 Blind flat fishes do not change colour, so we 

 know that the message from the outside world 

 first affects the eye. It travels to the brain, 

 and by the nervous system to the colour-cells 

 in the skin which can change their size and 

 position. In some instances the change oc- 

 curs in a minute or two, and it gives the fish 

 a garment of invisibility. 



In the aquarium at New York there is 

 often a startling display of coral-reef fishes 

 from the Bermudas and similar places. Their 

 colours are brilliant, and their patterns are 

 almost incredible. It seems to some natu- 

 ralists quite impossible that these colours and 

 patterns can have concealing value, partly 

 because they are so conspicuous, one might 

 almost say daring, and partly because they 



