To B. D. Walsh 13 April 
Down. | Bromley. | Kent. S.E.
My dear Sir
It was extremely kind of you after being ill & overworked with your Report to take so much trouble in looking through your collection & writing me such copious & minute notes.1 I value your information much, as I well know that you are so trustworthy. Not only are many of the facts, which you communicate, very interesting to me; but the negative evidence is of much value, for I was very doubtful how far I could trust the information, which I picked up from various Books & papers. Many of the English entomologists, however, have been most kind in assisting me in various ways.2 I have found my present subject of Sexual Selection very perplexing, & I must leave a multitude of points doubtful, & can seldom judge except by analogy. But I must make the best of a rather bad job.—
I hope that you will soon receive or have received my new Book, which I have lately heard, is to be republished in the U. States.—3 It is much too large a book, but if I had to do it again, I hardly know what I ought to strike out.— I see by the heading of your letter that you still retain your Editorship, which I fear you must find very hard work.—4
With cordial thanks, My dear Sir | Yours sincerely | C. Darwin
I have just read again your letter & it really is a mine of wealth to me.—
BDW’s letter [6051?] and his notes are a "mine of wealth". The negative evidence is of much value. Sexual selection is a perplexing subject – finds he "must make the best of a rather bad job".
Sends copy [of Variation].
Please cite as
Darwin Correspondence Project, “Letter no. 6113,” accessed on 25 October 2016, http://www.darwinproject.ac.uk/DCP-LETT-6113