To Gerhard Rohlfs   8 June 1871

Dear Sir

I thank you very sincerely for y^r kind letter, & for your notes, which shall be duly considered whenever I have to prepare a corrected edition of my last book—¹

The judgment of a man who like you, has made one of the most wonderful expeditions on record, certainly deserves the fullest consideration.²

With respect to the colour of desert animals I trusted to M^r Tristram, who I believe visited the borders of, if he did not penetrate into the Sahara.³

With great respect I beg leave to remain | dear Sir | yours faithfully & obliged | Ch. Darwin