Mimicry 



closely resemble wasps ; those of another are remarkably 

 like bumble-bees, even to the extent of having thickened 

 hind legs, like the pollen-bearing members of the bumble- 

 bee family. As this modification is perfectly useless to 

 the fly, it simply amounts to a device destined to add to 

 the fly's resemblance to a bee. 



In another chapter we referred to the leaf-cutting ants. 

 Those destructive creatures march in droves to some 

 favoured shrub, and each one nibbles a piece of leaf there- 

 from before returning home. On the homeward march 

 the booty, in the shape of a snippet of green leaf, is 

 carried on high over the insect's head and, an ant legion, 

 each member of which bears a green leaf, presents a 

 curious spectacle and affords an opportunity for a very 

 striking example of mimicry. 



So far all our mimetic insects have resembled a plant, 

 an insect or some non-living material ; but a bug which 

 lives in the same part of the world as the leaf-cutting 

 ants goes one better he mimics the ant plus his leafy 

 burden. This bug is a curious-looking creature, for on 

 his back he bears a thin, flattened outgrowth, green in 

 colour, which at a little distance bears a very striking 

 resemblance to a piece of green leaf, and he himself is not 

 unlike an ant. We may well inquire the reason for this 

 so-called aggressive mimicry. If it be of a purpose, as 

 some aver, it is surely intended to help the imitator to 

 more readily obtain its prey ; for the fly which resembles 

 the bumble-bee preys upon those insects or, in other cases, 

 it assists the mimic to avoid its enemies ; the moth which 

 mimics the hornet is not nearly so likely to meet with a 

 tragic end as a moth which does not possess this advan- 

 tage, for the sting of the hornet is notorious, even among 

 the lower animals. 



Amongst insects, there are other forms of protection 

 from their enemies which can hardly be termed mimicry or 

 even protective resemblance; perhaps protective colouring 

 would be a better term. These insects are all remarkable 



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