WCP4328

[1]

Holly House, Barking, E.

Dec^r. 31st. 1870

Dear M^r. Bennett¹

The Title of D^r. Laycock's² work is "Mind and Brain, or Correlations of Organisation and Consciousness". 2 vols. Simpkin & Marshall.³ I am surprised, Mr Murphy⁴ has not seen it, as his views seem to be very similar though I think better expressed than D^r. Laycock's; whose work is awfully involved & diffuse.

I do not see your difficulty in plants. There is no true protective mimicry in plants, but as plants need fertilisation ^{and diffusion} as much as animals need protection, the adaptations of plants are mostly to that end. In that sense the colours odours and secretions of flowers ^{and fruits} are as much protective adaptations as the colours, odours & habits of animals [2] but they take the form of conspicuousness rather than concealment. The only cases that can ^possibly be called mimicry are those of orchid flowers resembling insects but whether ^this is useful or not has not yet been proved; if not it is accidental or imaginary. The resemblance of one plant to another of a different order, is not mimicry, but simply the result of adaptation to similar conditions.

I do not want to discuss any more in print, but I must refer to one remark of yours — that if the obscurely coloured and imitative catterpillars had been rejected by birds it would have been claimed by the Darwinians as a fact in their favour.

Now consideration must show you; that if such were the fact, it would completely overthrow Darwin's⁵ theory. For the only reason [3] (on Darwinian principles) why they have obtained the protection of obscure, green, or imitative tints or habits, is because they were in danger & needed the protection. Had they been already protected by a disgusting odour or taste, it is evident they would not have needed the additional protection of concealment. Indeed before the experiment had been tried I predicted that the obscure & imitative catterpillars ought to be eatable, the gay coloured ones uneatable.

The foundation of the theory of mimicry is, that the insects protected by taste, odour, hardness, sting, or in any such way do not require the additional protection of concealment, and therefore cannot possibly acquire it by nat. selectⁿ. — While those which are the daintiest morsels & therefore in most danger of extermination, must [4] acquire a protective colouring or some other protection ^{such as} mimicry or cease to exist.

A. Murray's⁵ communication on the subject is really beneath contempt & I think ought not to have been printed, because it is not supported by any facts whatever.

Believe me | yours very faithfully | Alfred R. Wallace [signature]

A. W. Bennett Esq.