WCP3777

[1]

Rosehill, Dorking, Surrey

Sept. 6th, 1877

Dear Sir

Many thanks for the extract you have been so good as to send me from the "Revue des Deux Mondes"¹,— which ^article I will take the opportunity of reading shortly. It is rather curious that exactly the same effects should have been attributed to the tropical and the arctic sun in producing colour. It seems to me that the author has jumped to a conclusion on very insufficient facts. The arctic vegetation is necessarily one of excessively rapid development, the changes that take months in ^the temperate & torrid zones only occupying weeks in the arctic regions. The changes of colour in seeds to which the author chiefly refers, may be corrected with this [2] rapidity-of development rather than die due to any direct effect of sunlight. As to flowers I very much doubt the facts, but I will inquire into them. It strikes me that white & yellow flowers largely prevail in the arctic flora and that the darker & richer colours of temperate & tropical zones are absent. It is quite possible however, that the stimulus of light combined with a dry atmosphere may produce a condensation of the colouring matter in some vegetable products & thus a more intense colouration. This would be very different from the production of colour by light, & would be an indirect rather than a direct effect of its general action on the growth of plants. Thanking you again for your communication.

I remain | Yours very faithfully | Alfred R. Wallace- [signature]

Tho[ma]^s. Austin Jun[io]r. Esq.