Evidences of Theory of Natural Selection. 33 1 



main factor of organic evolution, by simply adding 

 illustrations of two further cases of mimicry, which are 

 perhaps even more remarkable than any of the fore- 

 going examples. The first of the two (Fig. ii5)speaks 

 for itself The second will be rendered intelligible by 

 the following few words of explanation. 



There are certain ants of the Amazons which 

 present the curious instinct of cutting off leaves from 

 trees, and carrying them like banners over their 

 heads to the hive, as represented in Fig. 116, B, where 

 one ant is shown without a leaf, and the others each 

 with a leaf Their object in thus collecting leaves is 

 probably that of growing a fungus upon the "soil" 

 which is furnished by the leaves when decomposing. 

 But, be this as it may ', the only point we are now con- 

 cerned with is the appearance which these ants present 

 when engaged in their habitual operation of carrying 

 leaves. For it has been recently observed by Mr. W. 

 L. Sclater, that in the localities where these hymenop- 

 terous insects occur, there occurs also a homopteroia 

 insect which mimics the ant. leaf and all, in a wonder- 

 fully deceptive manner. The leaf is imitated by the 

 thin flattened body of the insect, " which in its dorsal 

 aspect is so compressed laterally that it is no thicker 

 than a leaf, and terminates in a sharp jagged edge." 

 The colour is exactly the same as that of a leaf 

 and the brown legs show themselves beneath the 

 green body in just the same way as those of the ant 

 show themselves beneath the leaf So that both the 

 form and the colouring of the homopterous insect has 

 been brought to resemble, with singular exactness. 



' For a full account of this instinct and its probable purpose, see 

 Animal Intelligence, pp. 93-6. 



