THE LEAF BUTTERFLY. 



( Kallima paralekta. ) 



There are many instances of protec- 

 tive imitation or mimicry in nature, but 

 none are more pronounced, more perfect 

 or more interesting than that shown by 

 the leaf butterflies. Briefly defined, the 

 phenomenon of mimicry is that relation 

 which obtains when **a certain species of 

 plants or animal possesses some special 

 means of defense from its enemies and 

 some other species inhabiting the same 

 district or a part of it, and not itself 

 provided with the same special means of 

 defense, closely resembles the first spe- 

 cies in all external points of form and 

 color, though often very different in 

 structure and unrelated in the biological 

 order." Many animals, such as some 

 tree-lizards, resemble the colors of the 

 environment in which they live, either 

 for protection from enemies or in order 

 that they may more easily catch their 

 prey. Some arboreal snakes hang from 

 the boughs of trees like the drooping 

 ends of creeping vines. 



The coloring of the under surface of 

 the wings of the leaf buterflies very 

 closely resembles the color of a dried 

 leaf. As dried leaves vary in color and 

 appearance, so do the butterflies vary 

 in the color and markings of their wings. 

 It is said that even in the same species, 

 the under surface of the wings may be of 

 various shades of brown, yellow, ash 

 and red. But the imitation of the dried 

 leaf does not alone rest on the color, for 

 often, here and there, may be seen small 

 groops of dark colored spots which 

 strikingly resemble the patches of fungi 

 that are so common on leaves. The 

 mimicry of this butterfly is purely pro- 

 tective and not for the purpose of de- 

 ceiving its prey. 



Dr. Alfred Russel Wallace in his 

 "Malay Archipelago" writes of this but- 

 terfly as he found it in its native ele- 



ment. He says, "This species was not 

 common in dry woods and thickets, 

 and I often endeavored to capture it 

 without success, for after flying a short 

 distance it would enter a bush among 

 dry or dead leaves, and however care- 

 fully I crept up to the spot, I could never 

 discover it till it would suddenly start 

 out again, and then disappear in a sim- 

 ilar place. At length I was fortunate 

 enough to see the exact spot where the 

 butterfly settled, and though I lost sight 

 of it for some time, I at length discov- 

 ered that it was close before my eyes, 

 but that in its position of repose it so 

 closely resembled a dead leaf attached to 

 a twig as almost certain to deceive the 

 eye, even when gazing full upon it. I 

 captured several specimens on the wing, 

 and was able fully to understand the 

 way in which this wonderful resem- 

 blance is produced. 



'The ends of the upper wings termin- 

 ate in a fine point, just as the leaves of 

 many tropical shrubs and trees are point- 

 ed, while the lower wings are somewhat 

 more obtuse, and are lengthened out into 

 a short thick tail. Between these two 

 points there runs a dark curved line, ex- 

 actly representing the midrib of a leaf, 

 and from this radiate on each side a few 

 oblique marks, which well imitate the 

 lateral veins. These marks are more 

 clearly seen on the outer portion of the 

 base of the wings and on the inner side 

 toward the middle and apex, and they 

 are produced by striae and markings 

 which are very' common in allied species, 

 but which are here modified and 

 strengthened so as to imitate more ex- 

 actly the venation of a leaf. 



"The habit of the species is always to 

 rest on a dead twig and among dead or 

 dried leaves, and in this position, with 

 the wings closely pressed together, their 



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