The Wallace-Darwin Correspondence 



able to give us a volume per annum of your magnum opus^ 

 with all the fa<jts as you now have them, leaving additions 

 to come in new editions. 



I am working a little at another family of my butter- 

 flies, and find the usual interesting and puzzling cases of 

 variation, but no such phenomena as in the Papilionidae. — 

 With best wishes, believe me, my dear Darwin, yours very 

 faithfully, Alfred R. Wallace. 



6 Queen Anne Street, W, Monday, January, 1867. 



My dear Wallace, — I return by this post the Journals 

 Your r6sum6 of glacier action seems to me very good, and 

 has interested my brother much, and as the subject is new 

 to him he is a better judge. That is quite a new and per- 

 plexing point which you specify about the freshwater fishes 

 during the glacial period. 



I have also been very glad to see the article on Lyell, 

 which seems to me to be done by some good man. 



I forgot to say when with you — but I then indeed did 

 not know so much as I do now — that the sexual, i.e. orna- 

 mental, differences in fishes, which differences are some- 

 times very great, offer a difficulty in the wide extension of 

 the view that the female is not brightly coloured on account 

 of the danger which she would incur in the propagation of 

 the species. 



I very much enjoyed my long conversation with you; 

 and to-day we return home, and I to my horrid dull work 

 of correcting proof-sheets. — Believe me, my dear Wallace, 

 yours very sincerely, Charles Darwin. 



P.S. — I had arranged to go and see your collection on 

 Saturday evening, but my head suddenly failed after lun- 

 cheon, and I was forced to lie down all the rest of the day. 



^ Quarterly Journal of Science, January 7, 1867. " Ice Marks in North 

 Wales," by A. R. Wallace. 



M 177 



