MIMICRY 1595 



and beauty of their colors; but they are incapable 

 of rapid and sustained flight, and would for this 

 reason fall an easy prey to insect-eating birds. Their 

 wings, however, are never found among those re- 

 jected by insectivorous birds in places where the 

 remains of other butterflies frequently cover the 

 ground. The Heliconidae possess a powerfully dis- 

 agreeable and pungent odor, which is so little volatile 

 as to cling to the fingers for several days after hand- 

 ling one of these insects. Mr. Wallace inferred from 

 this that they have a disagreeable taste, and would 

 not on that account be eaten by birds. This was sub- 

 sequently found by Mr. Belt to be the case. 



Belonging to the family of the Pieridae, which is 

 quite distinct from the family of the Heliconidae, 

 and the greater number of which are white, there 

 is a genus of small butterfly named Leptalis, which 

 is eaten by birds. Some species of the genus Leptalis 

 are white, like their allies among the Pieridae, but 

 the majority of the Leptales have an exact resem- 

 blance to some species of the Heliconidae as far as 

 regards the peculiar shape and color of their wings. 



The structure of the two families is completely 

 different; in spite of this the resemblance is so strik- 

 ingly close that both the experienced entomologists 

 Mr. Bates and Mr. Wallace often at the time of 

 capture mistook the one for the other, and only dis- 

 covered their mistake by a closer examination. This 

 has been looked upon as the most typical example 

 of true mimicry, and is interesting from the fact that 

 it is the first instance to which the term mimicry was 

 applied. 



