THE GREAT DEEPS 129 



luminous plates just under its eyes. One of 

 these gives off red light and the other green, 

 and from the arrangement of the muscles con- 

 nected with them, it is thought that the fish 

 has control over them, and can turn on its 

 lamps at will, to warn off its enemies or to aid 

 it in the search for its prey ! 



" Very strange indeed would be the appear- 

 ance of these animals if we could see them in 

 the deep ! In the absolute darkness of the 

 abyss they would appear as ghostly, silver- 

 blue shapes, glimmering like an electric lamp 

 through dense fog on a dark, moonless night. 

 Of all the characters of deep-sea fishes 

 this almost universal phosphorescence is the 

 strangest." 



Another puzzle may be found in the fact that 

 many deep-sea animals are brightly coloured. 

 Bright red is common, for instance, in crus- 

 taceans, star-fishes, and sea-anemones. There 

 is very little in the way of pattern, but there is 

 not a little colour. What can be the meaning 

 of colour in a world of darkness ? It is highly 

 probable that the colours as such have no 

 significance in the life of these deep-sea animals, 

 that they are simply the useless by-products of 

 some of the fundamental processes that go on 

 9 



