My dear Sir

I thank you very sincerely for your letter and MS.¹ received a few days since: I am, however, really sorry that you should have had the expence and trouble of sending them to me. Your Plates are quite beautiful: they strike me as in every way truly admirable. Think of my case, who cannot draw; and when the drawings are made, have then to see that they are engraved: think of my case; and yet you speak of losing “tout mon gout pour les sciences naturelles”! The publication of such beautiful Plates, ought to give you, indeed, infinite satisfaction.

I have read only part of your MS. but I agree, as yet, with all you say; and your descriptions seem to me excellent. I made in part of my Book one mistake, which I see, you also, have fallen into, viz. speaking of baso-&c. lateral instead of basi-lateral.² In Plate I, fig. 6 I cannot help doubting whether this belongs to V. prisca: if you had not so named it, I should from this one view, have thought it a fixed scutum of another species of Verruca. I fear it was I who misled you³ (but I think I could not have been so forgetful) and led you to ⁠⟨⁠    ⁠⟩⁠⁴ V. Strömia is always marked with longitudinal ⁠⟨⁠    ⁠⟩⁠ but this is not the case, and will not ⁠⟨⁠    ⁠⟩⁠ prisca & Strömia. I think you will like ⁠⟨⁠    ⁠⟩⁠ when my Book is out, which shall be sent you, and what part of the ⁠⟨⁠    ⁠⟩⁠ and tagum⁵ becomes abnormally developed, when ⁠⟨⁠    ⁠⟩⁠ part of the wall of the shell. I am extremely ⁠⟨⁠    ⁠⟩⁠ engaged, but yet I hope to find time to give specific characters in my Synopsis speciorum⁶ of your new species. I do not suppose that the Ray Soc. will publish my work for several months. I thank you much for the sessile Cirripedes, and for their names and References. I believe B. perplexus = B. unguiformis of J. de C. Sowerby⁷ and B. sulcatinus, I have called bisulcatus;⁸ but without opercular valves it is rarely possible to identify sessile cirripedes with entire certainty. Please sometime inform me whether I must return the MS., and the sessile Cirripedes. In your mention of me you have done me very great honour.⁹

Pray believe me, with very cordial respect for your excellent labours. | My dear Sir | Your’s sincerely | C. Darwin.

Now that I see that you use Mitella, I much wish I had done so; but it is too late for me to change in my forthcoming Synopsis.¹⁰

P.S. I have now read half the MS. (which I suppose is very nearly all that you will publish) and I do not think that I have congratulated you enough on producing so excellent a Memoir.