We are also told that, the better to cozen his amphitryon, the parasite adopts more or less the same shape and colouring; he turns himself, in appearance, into a harmless neighbour, a worker belonging to the same guild. Instance the Psithyrus, who lives at the expense of the Bumble-bee. But in what, if you please, does Parnopes carnea resemble the Bembex into whose home she penetrates in her presence? In what does the Melecta resemble the Anthophora, who stands aside on her threshold to let her pass? The difference of costume is most striking. The Melecta's deep mourning has naught in common with the Anthophora's russet coat. The Parnopes' emerald-and-carmine thorax possesses not the least feature of resemblance with the black-and-yellow livery of the Bembex. And this Chrysis also is a dwarf in comparison with the ardent Nimrod who goes hunting Gad-flies.
Besides, what a curious idea, to make the parasite's success depend upon a more or less faithful likeness with the insect to be robbed! Why, the imitation would have exactly the opposite effect! With the exception of the Social Bees, who work at a common task, failure would be certain, for here, as among mankind, two of a trade never agree. An Osmia, an Anthophora, a Chalicodoma had better be careful not to poke an indiscreet head in at her neighbour's door: a sound drubbing would soon recall her to a sense of the proprieties. She might easily find herself with a dislocated shoulder or a mangled leg in return for a simple visit which was perhaps prompted by no evil intention. Each for herself in her own stronghold. But let a parasite appear, meditating foul play: that's a very different thing. She can wear the trappings of Harlequin or of a church-beadle; she can be the Clerus-beetle, in wing-cases of vermilion with blue trimmings, or the Dioxys-bee, with a red scarf across her black abdomen, and the mistress of the house will let her have her way, or, if she become too pressing, will drive her off with a mere flick of her wing. With her, there is no serious fray, no fierce fight. The Bludgeon is reserved for the friend of the family. Now go and practice your mimesis in order to receive a welcome from the Anthophora or the Chalicodoma! A few hours spent with the insects themselves will turn any one into a hardened scoffer at these artless theories.
To sum up, mimesis, in my eyes, is a piece of childishness. Were I not anxious to remain polite, I should say that it is sheer stupidity; and the word would express my meaning better. The variety of combinations in the domain of possible things is infinite. It is undeniable that, here and there, cases occur in which the animal harmonizes with surrounding objects. It would even be very strange if such cases were excluded from actuality, since everything is possible. But these rare coincidences are faced, under exactly similar conditions, by inconsistencies so strongly marked and so numerous that, having frequency on their side, they ought, in all logic, to serve as the basis of the law. Here, one fact says yes; there, a thousand facts say no. To which evidence shall we lend an ear? If we only wish to bolster up a theory, it would be prudent to listen to neither. The how and why escapes us; what we dignify with the pretentious title of a law is but a way of looking at things with our mind, a very squint-eyed way, which we adopt for the requirements of our case. Our would-be laws contain but an infinitesimal shade of reality; often indeed they are but puffed out with vain imaginings. Such is the law of mimesis, which explains the Green Grasshopper by the green leaves in which this Locust settles and is silent as to the Crioceris, that coral-red Beetle who lives on the no less green leaves of the lily.
And it is not only a mistaken interpretation: it is a clumsy pitfall in which novices allow themselves to be caught. Novices, did I say? The greatest experts themselves fall into the trap. One of our masters of entomology did me the honour to visit my laboratory. I was showing my collection of parasites. One of them, clad in black and yellow, attracted his attention.
'This,' said he, 'is obviously a parasite of the Wasps.'
Surprised at the statement, I interposed:
'By what signs do you know her?'
'Why look: it's the exact colouring of the Wasp, a mixture of black and yellow. It is a most striking case of mimesis.'
'Just so; nevertheless, our black-and-yellow friend is a parasite of the Chalicodoma of the Walls, who has nothing in common, either in shape or colour, with the Wasp. This is a Leucopsis, not one of whom enters the Wasps' nest.'
'Then mimesis...?'