168 ANIMAL LIFE 



and physiological significance of colour, we may 

 consider its modifications. Harmony with the varied 

 conditions of existence is the note of animal life. 

 The adaptations of colour to serve ends beyond 

 those of nutrition and respiration form part of that 

 general harmonious relationship between animals 

 and their environment. 



Amongst these adaptations none are more striking 

 than the sympathetic colourations of animals. With 

 but few exceptions, amongst gregarious species, the 

 attitude and colouring of animals renders them in- 

 conspicuous. 



Those which rest for long intervals reflect, as it 

 were, the light and shade, as well as the colouration 

 of their habitual surroundings. The tiger's stripes 

 sympathetically render the lights and shadows of 

 jungle grass, amid which it lies concealed a whole 

 day. The giraffe's dappling and the deer's spots give 

 back the sun-images and leaf-shadows that filter 

 through the foliage. The skate and turbot, sole and 

 shrimp, are speckled like the ground on which they long 

 rest, motionless. The skin becomes to all appearance 

 a sensitive plate, upon which, as by a process of colour- 

 photography, is imprinted the general tone and tinting 

 of the surroundings. So sensitive do prawns and 

 other sympathetically coloured animals become that, 

 if given a choice of station, they do not rest until they 

 have adjusted their dark areas to the shadows and 

 their bright spots to the shafts of light. But once 

 having accomplished this, they remain still for a long 



