Dear Sir,

I am much obliged for your interesting letter.¹ The case is quite new to me, & may perhaps explain other instances in which the magnificent colours in the wings of butterflies appear only from certain points of view. If you or any one had actually observed in Celebes² the male approaching the female in the proper position for displaying his colours, the case would have been well worth publishing. When I next go to London I will look at this butterfly in the British Museum, that I may be able fully to appreciate your description. I will then perhaps give an account of your remarks in “Nature”.³

Dear Sir, | Yours faithfully & obliged | Charles Darwin.