My dear Sir

Your letter has given me much pleasure,—more than you would anticipate, & more perhaps than it ought to do,—though I put down part of what you say to the kindness of disposition, which I have observed in your memoirs & in your letters to me. I have had a short letter from Müller of Berlin, expressing interest in my Book, and now, with what you have said, I feel highly satisfied, & can go on with my work with a good heart:¹ You will perhaps be surprised at all this; but I think everyone wants sympathy in their pursuits, & I live a very retired life in the country, & for months together see no one out of my own large family.

With respect to what you say on the homologies of the larva in the first stage, I confess to have gone through more doubt than on any other part: for some time I thought the three pairs of legs corresponded with the mandibles, the inner & outer maxillæ, for I must still believe in there being (potentially) two pairs of antennæ in the earliest stage; but the description of the larva in the second stage by Burmeister (whose paper by the way is dreadfully incorrect)² & the somewhat varying position of the mouth in the first stage, led me to the view which I have taken.—³ I hope that, whenever you have an opportunity that you will attend to the adhesion of the Lerneidæ:—⁴ the method of attachment, which I have described is certainly the great character of the class of Cirripedia.—⁵

I thank you much for your wish for me to have the Cirripedia of the Expedition, but I know well how impossible it is.⁶ Your information on the Corals has been most useful; for in the two cases in which you speak most positively, are the very two, to which I have not the smallest clue for habitat.⁷

I am most vexed at the wooden-pill Box with the Crustacean having been lost: I put it in the parcel myself:⁸ I suppose the parcel must have been opened at your Custom House & so the little Box lost: I have got Bailliere⁹ to write to New York to enquire: I had hoped this would have turned out of some interest to you.—

I have lately been reading the vols. for the last dozen years of Silliman’s Journal,¹⁰ with great interest: What a curious account is that on the blind Fauna by M^r Silliman, of the caves.—¹¹ I feel extreme interest on the subject, having for many years collected facts on variation, &c &c.—¹² Would it be possible to procure one of the Rats for the British Museum? I should so like my friend M^r. Waterhouse to examine the teeth & see whether it is an old or new world form.¹³ If ever you could oblige the naturalists on this side of the water by getting so interesting a specimen, would you send it to me to give to Waterhouse; for (privately between ourselves) it would be of little use to real science, if once in the hands of M^r. Gray;¹⁴ —but very likely I am asking for an impossibility; the rats may be very rare. It is not stated whether the optic nerve was dissected out, which would be a curious point.—

I read over again in the Journal several of your papers; if I had space I should have liked to have fought a friendly battle with you on the Australian valleys; I see I have not stated my side versus fresh water in nearly enough detail.¹⁵

Did you not observe the great high plain forming peninsulas running laterally into the valleys, (& I suspect almost truly insulated masses); and these seem to me to be very improbable on the running water theory. Again, as far as I saw, & as appears on maps, the line of drainage never seems to lie at foot of precipices on either side; & it appears to me that this might be expected to occur here & there, if the valleys were still in process of excavation.— but I had no intention to discuss this subject when I began, or to trouble you with so very long a letter.

Accept my thanks for your very kind letter, & believe me | Very sincerely your’s Charles Darwin.—