130 THE VALUE OF COLOUR 



There are many naturalists, espeqially students 

 of insects, who appear to entertain an inveterate 

 hostility to any theory of Mimicry. Some of 

 them are eager investigators in the fascinating 

 field of geographical distribution, so essential for 

 the study of Mimicry itself. The changes of 

 pattern undergone by a species of Erebia as we 

 follow it over different parts of the mountain 

 ranges of Europe is indeed a most interesting 

 inquiry, but not more so than the differences 

 between e.g. the Acraea johnstoni of S.E. Rhodesia 

 and of Kilimanjaro. A naturalist who is interested 

 by the Erebia should be equally interested by the 

 Acraea; and so he would be if the student of 

 Mimicry did not also record that the characteristics 

 which distinguish the northern from the southern 

 individuals of the African species correspond with 

 the presence, in the north but not in the south, 

 of certain entirely different butterflies. That 

 this additional information should so greatly 

 weaken, in certain minds, the appeal of a 

 favourite study, is a psychological problem of 

 no Httle interest. This curious antagonism is 

 I beheve confined to a few students of insects. 

 Those naturalists who, standing rather farther off, 

 are able to see the bearings of the subject more 

 clearly, will usually admit the general support 

 yielded by an ever-growing mass of observations 

 to the theories of Mimicry propounded by 

 H. W. Bates and Fritz Muller. In like manner 

 Natural Selection itself was in the early days 



