202 BATES'S THEORY. 



and lines and patches ; their wings are rather long and 

 narrow and they bear an easily recognized and common 

 likeness. Fig. 9 illustrates a pair, ^ and ^ ,of Acrcsa acara 

 from East Africa, together with two, $ and ^ o{ A. Natalica 



Fig. 9. ACR.^IN^, (Africa.) 

 Acra-a acara i Acvcea acai-a 9 



A. NataJica i A. Natalica ? 



from the same locality ; the prevailing colours, markings, 

 spots, shape, and general appearance being remarkably 

 alike and beautiful. 



V. Mimicry or Sinmlism : Bates's tJieory. 



It is to the late H. W. Bates that we owe the term 

 • mimicry ' in relation to insects. The word is rather 

 unhappily chosen as it implies conscious and even voluntary 

 imitation, which certainly do not exist in the insect world. 

 It has however, been in use so long that its intended 

 significance is generally recognized amongst entomologists 



