Dear Sir

I have been deeply interested by your most kind letter.—² I naturally feel much curiosity on the progress of opinion on the descent of species, & I am delighted to hear that the subject is progressing in Germany which so abounds with great naturalists.— But what you tell me about yourself interests me the most, & I thank you sincerely for your confidence. I feel what you say in praise of my book & your intention of carrying onwards & perfecting the subject, as by far the greatest honour which could be paid me. I was shewn in London your magnificent work on Radiolariæ.³ The passage which you refer to was pointed out to me & I was struck by it & admired the boldness of your expressions.⁴

I am grieved to hear that you have suffered any heavy calamity;⁵ but at so early a period of life I cannot but hope that time, the great allayer of all evils, will do much for you. I am rendered by ill–health old for my years, which are 56,⁶ but I still feel a lively interest on many subjects, & your letter has delighted me. I have thought that perhaps you w^d like to have a photograph of me (lately taken by one of my sons) & which I enclose.⁷ Some time I hope that you will have the goodness to send me your photograph, as I should much like to possess a copy.

I am very much obliged for your promised book, which I will read with care, for what you say on individual variability in the Cœlenterata is very remarkable; & this kind of variability has been greatly neglected by naturalists.⁸ I have however a very bad head for languages; & every German book takes me a long time which is a great evil, there is so much to read in German. I am slowly recovering from a long illness, which has quite prevented all work; but I hope soon to resume my nearly finished book on “Variation under Domestication”;⁹ in the mean time, I have been doing a little easy Botanical work, & one of the papers which I have prepared, will possibly interest you as it relates to reproduction & when printed I will send you a copy.¹⁰

This kind of work being in some degree new to me, I have been much struck with the interest which the theory of descent & modification gives to all researches in Natural History; for I was able to use my own views with a feeling of novelty almost as if I had only lately learnt them.

Pray present my respects to Schleicher & Gegenbaur.¹¹ I am much pleased to know that men so distinguished agree to a large extent with my views.

Accept my cordial thanks for your long letter which has interested me in a high degree

I remain with much respect | Dear Sir | yours very sincerely | Charles Darwin