18 Cornwall Terrace, Regent's Park, N.W.: June 18.
Very many thanks for your permission to use your observations, as well as for the additional information which you have supplied. If all the manuscript chapter on instinct is of the same quality as the enclosed portion, it must be very valuable. Time will prevent me from treating very fully of instinct in my lecture, but when I come to write the book for the International Science Series on Comparative Psychology, I shall try to say all that I can on instinct. Your letter, therefore, induces me to say that I hope your notes will be published somewhere before my book comes out (i.e. within a year or so), or, if you have no intention of publishing the notes, that you would, as you say, let me read the manuscript, as the references, &c., would be much more important for the purposes of the book than for those of the lecture. But, of course, I should not ask to publish your work in my book, unless you have no intention of publishing it yourself. I do not know why you have kept it so long unpublished, and your having offered me the manuscript for preparing my lecture makes me think that you might not object to lending it me for preparing my book. But please understand that I only think this on the supposition that, from its unsuitable length, isolated character, or other reason, you do not see your way to publishing the chapter yourself.
From C. Darwin, Esq.
Down: June 19.
My dear Romanes,—You are quite welcome to have my longer chapter on instinct. It was abstracted for the Origin. I have never had time to work it up in a state fit for publication, and it is so much more interesting to observe than to write. It is very unlikely that I should ever find time to prepare my several long chapters for publication, as the material collected since the publication of the Origin has been so enormous. But I have sometimes thought that when incapacitated for observing, I would look over my manuscripts, and see whether any deserved publication. You are, therefore, heartily welcome to use it, and should you desire to do so at any time, inform me and it shall be sent.
Yours very sincerely,
Charles Darwin.
From G. J. Romanes to C. Darwin, Esq.
18 Cornwall Terrace: June 21, 1878.