“Down. “DEAR SIR--I have some doubts whether Fritz Müller would like extracts from his letters being published after so long an interval,--that is if the letter relates to the origin of mimicry; for he published about a year ago an excellent paper on this subject. I believe it was in the Jenaische Zeitschrift, but the paper is out of its proper place in my library and I cannot find it. If you thought it worth while to send me your copy I could then judge about the publication of extracts. “I fear it is not likely that I shall have anything to communicate to the Entomological Soc. I quite agree with you that it is a great pity that our Entomologists should confine themselves to describing species. “Dear Sir, yours faithfully, “CH. DARWIN.” * * * * * “_Sept. 22nd_ [1877]. “Down. “MY DEAR SIR--I am doubtful whether speculations in a letter ought to be published, especially after a long interval of time. Any fact which he states, I feel pretty sure he would not at all object being used by anyone.--Pray do the best you can.--I should grieve beyond measure to be accused of a breach of confidence.--He has lately, as I mentioned, thrown much light on the first steps in mimicry. “With respect to dimorphic Butterflies, those about which I have read appear at different seasons, and have been the subject of an _admirable_ essay by Prof. Weismann. It is some little time since I read the essay and one subject drives another out of my head, but I think he explains all such cases by the direct inherited effects of temperature. He tried experiments. If you read German, I believe I could find Weismann’s essays and lend them to you. In your present interesting case I really do not know what to think: it seems rather bold to attribute the 2 coloured forms to nat. selection, before some advantage can be pointed out.--May not the female revert in some cases? I do not doubt that the intermediate form could be eliminated as you suggest. “I wish that my opinion could have been of any value.... “I remain yours very faithfully, “CH. DARWIN.”