in PROTECTIVE RESEMBLANCES AMONG ANIMALS 57 



which catch insects on the wing, and that they destroy many 

 butterflies is indicated by the fact that the wings of these 

 insects are often found on the ground where their bodies 

 have been devoured. But among these there are no wings of 

 Heliconidae, while those of the large showy Nymphalidse, 

 which have a much swifter flight, are often met with. Again, 

 a gentleman who had recently returned from Brazil stated at 

 a meeting of the Entomological Society that he once observed 

 a pair of puffbirds catching butterflies, which they brought to 

 their nest to feed their young ; yet during half an hour they 

 never brought one of the Heliconidse, which were flying lazily 

 about in great numbers, and which they could have captured 

 more easily than any others. It was this circumstance that 

 led Mr. Belt to observe them so long, as he could not under- 

 stand why the most common insects should be altogether 

 passed by. Mr. Bates also tells us that he never saw them 

 molested by lizards or predacious flies, which often pounce on 

 other butterflies. 



If, therefore, we accept it as highly probable (if not proved) 

 that the Heliconidse are very greatly protected from attack by 

 their peculiar odour and taste, we find it much more easy to 

 understand their chief characteristics their great abundance, 

 their slow flight, their gaudy colours, and the entire absence 

 of protective tints on their under surfaces. This property 

 places them somewhat in the position of those curious wingless 

 birds of oceanic islands, the dodo, the apteryx, and the moas, 

 which are with great reason supposed to have lost the power 

 of flight on account of the absence of carnivorous quadrupeds. 

 Our butterflies have been protected in a different way, but 

 quite as effectually; and the result has been that as there has 

 been nothing to escape from, there has been no weeding out 

 of slow flyers, and as there has been nothing to hide from, 

 there has been no extermination of the bright-coloured varieties, 

 and no preservation of such as tended to assimilate with sur- 

 rounding objects. 



Now let us consider how this kind of protection must act. 

 Tropical insectivorous birds very frequently sit on dead 

 branches of a lofty tree, or on those which overhang forest 

 paths, gazing intently around, and darting off at intervals to 

 seize an insect at a considerable distance, which they generally 



