Evidences of Theory of Natural Selection. 331 
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- 
goingexamples. The first of the two (Fig. 115) 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 homopterous 
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, 
1 For a full account of this instinct and its probable purpose, see 
Animal Intelligence, pp. 93-6. 
