THE COLOURS OF ANIMALS AND PLANTS 123 



c. Alluring resemblances ; constituting a small 

 group of cases, in which an animal acts as a 

 bait by taking on the form of something 

 attractive to its prey. 

 Sematic Colours have two subdivisions : 



a. Warning colours. These constitute a curious 



group of cases, in which animals have bright 

 conspicuous colours, for the purpose of 

 warning other animals off them, and which 

 are signs of inedibility or of the possession 

 of dangerous powers of attack. 



b. Recognition colours. These are for the purpose 



of easy recognition by animals of the same 

 kind ; and are best seen in the cases of 

 gregarious animals, such as deer, whose 

 safety largely depends on association and 

 mutual defence. 



Protective Resemblances. 



Such forms of protective colouring as aid the 

 escape from enemies by hindering recognition may 

 be one of two kinds : 



(1) General ; in which the colouring is such as to 

 assimilate the animal to its environment, and so 

 render it less conspicuous, as in the case of the 

 whiteness of Arctic animals, such as the Polar bear ; 

 and the sandy colour of desert animals, or the trans- 

 parent blueness of pelagic forms. 



(2) Special ; where the resemblance is to some 

 particular object, and where the animal escapes, not 

 through being concealed from view and so over- 



