British Amphibians : Newts 



then appearing. The creature has very bright 

 eyes. 



The abnormal colouring of the male at the breeding 

 season is worthy of special remark : it occurs commonly 

 among amphibians, and there are instances of it in other 

 animals ; for example, in the male Stickleback which 

 almost bristles with colour under sexual impulse and 

 when fighting. But it is not only during the breeding 

 season and among males that changes of coloration 

 occur, for a number of amphibians are able to change 

 colour to harmonize with their surroundings ; and this 

 blending with environment is undoubtedly protective. 

 The changes of colour are due to rearrangement of 

 variously coloured pigments existing in minute particles 

 in the cells of the skin. The variously coloured pigment 

 particles are frequently huddled together in the middle 

 of each cell, but under emotion they are, as it were, 

 arranged, perhaps particles of one particular colour 

 spreading over all the cells and obscuring particles of 

 other colours. These rearrangements are not due to 

 voluntary or conscious effort on the part of the animal, 

 but to emotion, such as fear, anger, or sexual impulse. 

 We know that a blush is involuntary, and that we may 

 grow livid under anger or white with fear. The 

 abnormal colouring of the male newt under considera- 

 tion during the breeding season, like that of other 

 animals under similar circumstances, is undoubtedly 

 due to the ardent activity of the sexual impulse. 



The breeding season varies somewhat, and while the 



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