IN DEFENSIVE COLORATION 327 



A*. Synaposematic or Common Warning Colours 

 (Mullerian Mimicry). 



This subject, though logically but a section of Apo- 

 sematic Colours, is of such vast importance that it is 

 here converted into a separate heading equivalent to 

 A. Aposematic, and marked with an A*. 



Animals with Warning Colours often tend to resemble 

 each other superficially, as was pointed out by H. W. 

 Bates in his paper on the Theory of Mimicry. 1 He 

 showed that the conspicuous, presumably unpalatable, 

 tropical American butterflies, belonging to very different 

 groups, which are mimicked by other species, also tend 

 to resemble each other, the likeness being often remark- 

 ably exact. The resemblances were not explained by 

 Bates's Theory of Mimicry, and he could only suppose 

 that they had been produced by the influence of a 

 common environment, a suggestion at first adopted by 

 Wallace but abandoned by him as soon as Fritz Miiller's 

 hypothesis appeared in 1879. 2 



It seems probable that Bates was misled by a failure to 

 realize the remoteness of the affinity borne by the Heli- 

 coninae to the Ithomiinae, and that consequently the mimi- 

 cry between them did not appeal strongly to him. He 

 indeed saw and described the important structural differ- 

 ences, but still left them united as Heliconidae, calling 

 the Heliconinae, Acraeoid, and the Ithomiinae (including 

 the Danaine genera Lycorea and Itund) Danaoid. The 

 superficial resemblances were so close in shape as well as 

 pattern of wing that he was driven to accept an arrange- 

 ment which gave too little weight to characters of greater 

 importance. 



As a solution of the difficulty Fritz Miiller suggested 

 that life is saved by a resemblance between the Warning 

 Colours in any area, inasmuch as the education of young 



1 Trans. Linn. Soc, Lond., vol. xxiii, 1862, p. 495. The fact that 

 these examples were not figured in the accompanying plates probably 

 explains the long delay in the appearance of the Mullerian hypothesis. 

 See pp. 211-12 of the present work. 



2 Kosmos, May, 1879. 



