192 



ANIMAL COLORATION. 



way, of a butterfly's wing, and it is just possible that they 

 may play an analogous part in protecting the fish from its 

 foes. It has been already mentioned that the butterflies' 

 wings may be in some cases an actual defence, on account of 

 their very couspicuousness; they may divert attention from the 



Fig. 23. Flying Gurnard. 



more vital parts. So, in the case of the grayling, a young and 

 inexperienced pike may make a futile attack upon the con- 

 spicuous waving fins, and thus give the grayling time to escape 

 before the attack can be renewed. 



The large and brightly coloured fins of other fishes, for 

 example of the species depicted in the woodcut (fig. 23), may 

 be very possibly used for a similar purpose. 



