My dear Sir

I am sorry to say that before receiving your letter of July 17^th the new edit. of the Origin had been despatched by Murray for you.¹ I received safely your paper exposing Dana’s mis-quotations; I never c^d. persuade myself that there was much or any thing in Dana’s paper, but I see it is taking effect in the United States²

I have read Prof. Clark’s book³ & was interested by it on psychological principles as shewing how differently two men viz. the writer & the reader can view the same subject. I am heartily glad that you are making progress with your Cynips experiment.⁴ The new gall which has spread so wonderfully in England (& about which by the way there was a letter 2 days ago in the Times)⁵ is attached not to the leaf but to twigs; so that the bushes are rendered conspicuous in the winter by their numbers. I do not think any one can define an ovule from a bud; the only difference being, as many now view the case, that the former must be fertilized.

Have you seen Balbiani’s extraordinary paper on the vivaparous aphides being at a very early age hermaphrodites:⁶ he is a capital observer, & Sir J. Lubbock tells me that he has no doubt the appearances are true, for he has seen the same in Coccus, whether the interpretation be correct or not.⁷

Some of the Germans, as Prof. Claus, have been taking up a subject which I am glad of, namely to ascertain the amount, in order to test my views, of the individual variability of some of the commoner lower animals; & they find it very great.⁸

My dear Sir | yours very sincerely | Ch. Darwin