258 ROMANCE OF THE INSECT WORLD CHAP. 



been in any way concerned in the production of these 

 remarkable mimetic analogies. It is true the 

 mimicker often copies the mimicked in flight, and in 

 other habits. But this has probably arisen in precisely 

 the same manner as the imitation of colour and form, 

 by the gradual operation of natural selection, which 

 generation after generation would tend to preserve 

 the individuals whose flight best resembled that of the 

 model, just as it preserved those whose form and 

 colour most closely approached those qualities in the 

 imitated insects. The less perfect degrees of resem- 

 blance would be gradually eliminated, and only the 

 others left to propagate their kind. The meaning 

 expressed is the same in effect as voluntary actions, 

 and in this sense alone the term Mimicry was adopted 

 by Mr. Bates. 



Plainly Mimicry is in reality a very important phase 

 of special protective resemblance, it is an adaptation of 

 precisely the same nature. In the one case an insect 

 gains advantage by superficial imitation of a vegetative 

 or some inanimate object, in Mimicry the animal is 

 benefited by superficial resemblance to another living 

 insect. But while in ordinary protective resemblance 

 the simulated appearance is used for concealment, in 

 the case of mimicry its purpose is to attract attention. 

 The causes involved in the production of the two 

 phenomena are identical. They are the selecting 

 agency of natural selection, the law of the survival 

 of the fittest, or the preservation of favoured races in 

 the struggle for life. 



In tropical America, the Heliconidae and the 

 Danaidae which resemble them are mimicked chiefly 



