252 ROMANCE OF THE INSECT WORLD CHAP. 



tion to the general similarity which prevails throughout 

 immense numbers of species in these protected groups. 

 In many cases, the species in each group are closely 

 related, but in some instances the similarity has 

 arisen between species belonging to very different 

 groups. The resemblance of the Danaids of tropical 

 America to the Heliconias of the same localities 

 probably constitute a most interesting example of 

 similarity of forms which were originally unlike. 

 These Heliconoid Danaids, as they are called, have 

 acquired in a wonderful manner the colours and wing- 

 shape of their models the Heliconias, and are distinct 

 from all the other ^members of the group. The ad- 

 vantage derived is mutual, for their enemies have to 

 learn only one type of colouring and form and but the 

 same motion in flight 



Obviously the advantage leans greatly to one side 

 where of a group protected by corresponding colours 

 and patterns certain of the number are possessed of 

 comparatively less unpleasant attributes, an imper- 

 fection that they effectively hide under the more 

 complete protection of the species resembled. 

 Although these resemblances contain in them an 

 element of true Mimicry, and reap some of its 

 advantages, they must be distinguished from that 

 principle. Those cases where the mimicking and the 

 mimicked species cannot be said to differ as regards 

 their unpleasant qualities approach less near to true 

 Mimicry. 



Warning colour and conspicuonsness may protect 

 the forms developing them in another fashion. 

 Attention is directed to some unimportant part, 



