1896. THE INFLUENCE OF MIND IN EVOLUTION. 299 



are prolonged to form the stalk of the leaf. In connection with this 

 extraordinary combination ot form and colour, let us consider the habits 

 of the insect. Though it inhabits shady forests and shuns strong sun- 

 light, it flies by day, its brilliant hues of course making it a conspicuous 

 object ; but its flight is exceptionally powerful, and it has little to fear 

 on the wing. When it requires to rest, however, it does not do so, like 

 almost all other butterflies, on the under-side of a leaf, but on the bare 

 trunk, or one of the larger boughs, of a tree. Another fact to be noted 

 is that it does not feed on the nectar of flowers, but is greedily fond of 

 the juices that exude from the wounded bark of certain trees. These 

 habits, of course, expose it in a special degree to those tree-lizards 

 which are by far the worst of all the enemies that butterflies have in 

 tropical forests. The ease with which a butterfly may often be caught 

 with the finger and thumb proves how little their imperfect eyesight 

 secures them against an enemy approaching cautiously from behind. 

 They see a little better in front of them, and I have noticed that the 

 ieaf-butterfly always alights head downwards, so as to face anything 

 coming up the tree, which is much the most likely direction of assault 

 from a lizard. [In pictures generally, and in the showcase at the 

 British Museum (Natural History), the butterfly is turned the opposite 

 way, facing upwards, which is, no doubt, more appropriate to its 

 character as a leaf; but that is a detail rather above the intelligence 

 of a lizard : at any rate, I never saw a Kallima sit in that position.] 

 It also abstains entirely from opening its wings and displaying its 

 glories to the sun, as almost all brightly coloured butterflies are so fond 

 of doing : it sits rigidly motionless. But all these precautions would 

 not save it without its wonderful disguise. How effectual that may 

 be was vividly brought home to me once by another deceiver of the 

 same character, a kind of slow cricket which exactly resembles a small 

 patch of grey lichen. I was sitting high up in a tree, rifle in hand, 

 waiting for a tiger, when my attention was caught by one of these 

 crickets scurrying round the trunk of a neighbouring tree, with a 

 lizard in full pursuit. Just as the lizard came up with it, the cricket, 

 falling in with a slight depression in the bark, stopped dead and flat- 

 tened itself out, and the lizard was utterly confounded. There it 

 stood, looking ludicrously puzzled at the mysterious disappearance of 

 its prey, which was just under its nose. 



In both these examples we find a most extraordinary disguise 

 associated with peculiar habits not shared by undisguised members of 

 the same family, and these are not merely passive habits, or habitual 

 attitudes, but active habits. That the tendency to act so under such 

 circumstances was evolved by natural selection side by side with the 

 disguise, even granting that there existed an initial likeness from some 

 •other cause, is not easily conceivable, at least to my mind. Moreover, 

 there is in the behaviour of the insect something that distinctly 

 indicates the play of at least a dim kind of intelHgence. The cricket 

 at first yielded to a primary and almost universal instinct and ran 



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