WCP2248

[1]

12 Victoria Road

Kensington

London

May 19. [18]70.

Dear Sir

You will kindly excuse that I did not send you the Translation earlier but I was some days away. It is as follows:

Freiburg ⁱ/Breisgau (Baden)

13. Dec[ember]. 1868.

Most honoured Sir

You had the kindness to forward to me your valuable publication on the variation and geographical distribution of the butterflies of Eastern Asia,¹ for which I herewith thank you most heartily. I should have done so sooner, had it not been for a pertinacious eye ache which checks me in my professional occupation, so that only at this moment I have finished studying [2] your most interesting treaty. Of course I knew it long ago by its title and principal tenor, however only from the short report, which Gerstäcker^{2, 3} had made on it. It is indeed a very interesting fact and which by no means can be explained through the old theory of Creation, that Polymorphismus occurs in such a striking manner among several tropical butterflies. I am not surprised that until now, owing to the geographical circumstances, which are much less favourable to a real Polymorphismus has not been observed as yet in Europe, owing to the geographical circumstances which are necess much less favourable to it, than in the Malay Archipelago. Of especial importance seems to me to be your observation that frequently two forms of females are [3] found on the very same locality: the primitive form as well as one of the derivative forms; because this besides ^some other facts speaks decidedly against the Law of migration of organisms, lately established by Mortiz Wagner.^{4, 5}

According to this a species is said to be able to perform its transformation into a new one only in that case, when <it> has isolated itself by the migration of a few individuals and thus has established a colony of its own, which keeps entirely separate from the individuals of the other species. I have opposed this view in a little pamphlet "On the right (reasonableness: justification:) of the Darwin Theory",⁶ by attempting to demonstrate, that it is very possible that the separation of a species into two new ones can take place at the same locality. [4] I would willingly forward to you a copy of this essay, but unfortunately I have not one left at this moment. As soon as I may again get one ^it, I shall take the liberty of sending you one. In the mean time I send you my researches on the development of the Corethra,^{7, 8} which perhaps may be of some interest to you.

Yours respectfully | Dr. Aug. Weismann⁹

You know perhaps that one of the most striking discoveries of Professor Weismann is that — though I believe it must be ascertained by another observer before it can be accepted — that the organs of the Imago do not develop themselves out of the organs of the pupa but that the organs of the latter are totally dissolved and [5] those of the former quite new formed! —

The in Weismann's letter mentioned name of Gerstäcker reminds me that I forgot to tell you that the Elaphomia cervicornis and E. Wallacei (Vol II of your Malay Archipelago)¹⁰ have been described before [by] Saunders (as Gerstäcker himself told me) as Phytalmia cervicornis and Ph. megalotis by Gerstäcker of Berlin. I possess this paper and the plate belonging to it.¹¹

I thank you very much for your paper on the trade[?] etc.[?], and for your remarks on guns[?]¹²

The paper of Moritz Wagner, Professor of Munich "on the law of migration" mentioned in the letter of Weismann will be known in England I think, else I should wish to translate it, as it is a very important and interesting one. [6] I just was reminded to [sic] it by the remarks of Mr. Bates¹³ in the last meeting of the Entomological Society: on the differences of species in the seperate [sic] valleys of the Amazon and farther west;¹⁴ just the same observations are made by Professor Moritz Wagner who has also been longtime in South America. I think you will get a letter from him¹⁵ as he wrote to me after having read my pamphlet on you and Darwin¹⁶ and asked for your address.

Believe me | Dear Sir | Yours most truly | Adolf Bernhard Meyer [signature]