54 SOME CRITICISMS [ch. 



alhomaculata as approached most nearly to H. misippus 

 in pattern, and so brought about the resemblance. 

 The explanation is ingenious, but a simpler view will 

 probably commend itself to most. Other cases are 

 known in which two butterflies bear a close resemblance 

 in pattern and yet are widely separated geographically. 

 Several species of the S. American Vanessid genus 

 Adelpha are in colour scheme like the African Planema 

 poggei which serves as a model for more than one 

 species. The little S. American Phyciodes leucodesma 

 would almost certainly be regarded either as a model 

 for or a mimic of the African Neptis nemetes, did the 

 two occur together. Nevertheless examples of close 

 resemblance between butterflies which live in different 

 parts of the world are relatively rare and serve to 

 emphasise the fact that the great bulk of these 

 resemblance cases are found associated in pairs or in 

 little groups. 



(2) That the imitators are always the more defenceless. 



In the case of butterflies " defence" as a rule denotes 

 a disagreeable flavour rendering its possessor distasteful 

 to birds and perhaps to other would-be devourers. 

 Feeding experiments with birds (cf. Chapter IX) 

 suggest that certain groups of butterflies, notably 

 the Danaines, Acraeines, Heliconines, Ithomiines and 

 Pharmacophagus PapUios — groups from which models 

 are generally drawn — are characterised by a disagreeable 

 taste, while as a rule this is not true for the mimics. 

 This distasteful quality is frequently accompanied 

 by a more or less conspicuous type of coloration. 



