44 NATURAL SELECTION in 



of rich orange on a deep-bluish ground. The under side is 

 very variable in colour, so that out of fifty specimens no two 

 can be found exactly alike, but every one of them will be of 

 some shade of ash or brown or ochre, such as are found 

 among dead, dry, or decaying leaves. The apex of the upper 

 wings is produced into an acute point, a very common form 

 in the leaves of tropical shrubs and trees, and the lower 

 wings are also produced into a short narrow tail. Between 

 these two points runs a dark curved line exactly representing 

 the midrib of a leaf, and from this radiate on each side a few 

 oblique lines, which serve to indicate the lateral veins of a 

 leaf. These marks are more clearly seen on the outer por- 

 tion of the base of the wings, and on the inner side towards 

 the middle and apex, and it is very curious to observe how 

 the usual marginal and transverse striae of the group are here 

 modified and strengthened so as to become adapted for an 

 imitation of the venation of a leaf. We come now to a still more 

 extraordinary part of the imitation, for we find representations 

 of leaves in every stage of decay, variously blotched and mil- 

 dewed and pierced with holes, and in many cases irregularly 

 covered with powdery black dots gathered into patches and spots, 

 so closely resembling the various kinds of minute fungi that 

 grow on dead leaves that it is impossible to avoid thinking at 

 first sight that the butterflies themselves have been attacked 

 by real fungi. 



But this resemblance, close as it is, would be of little use 

 if the habits of the insect did not accord with it. If the 

 butterfly sat upon leaves or upon flowers, or opened its wings 

 so as to expose the upper surface, or exposed and moved its 

 head and antennae as many other butterflies do, its disguise 

 would be of little avail. We might be sure, however, from 

 the analogy of many other cases, that the habits of the insect 

 are such as still further to aid its deceptive garb ; but we are 

 not obliged to make any such supposition, since I myself had 

 the good fortune to observe scores of Kallima paralekta, in 

 Sumatra, and to capture many of them, and can vouch for the 

 accuracy of the following details. These butterflies frequent 

 dry forests and fly very swiftly. They were never seen to 

 settle on a flower or a green leaf, but were many times lost 

 sight of in a bush or tree of dead leaves. On such occasions 



