My dear Hooker

I read yesterday the Notes on Round Isl^d. which I owe to you.—² Was there ever such an enigma? If in the course of a week or two you can find time to let me hear what you think, I sh^d. very much like to hear. Or we hope to be at Erasmus on March 4^th for a week;³ would there be any chance of your coming to Luncheon then? What a case it is.— Palms, Screw-Pines, 4 snakes, not one living on main island, Lizards, insects & not one Land Bird. But above everything such a proportion of individual monocotyledons! The conditions do not seem very different from the tuff Galapagos isl^d;⁴ but as far as I remember very few monocotyledons there. Then again the isl^d seems to have been elevated. I wonder much whether it stands out in the line of any oceanic current, which does not so forcibly strike the main island?

But why, oh why, sh^d so many cotyledons have come there; or why sh^d. they have survived there more than on main island, if once connected?⁵ So again I cannot conceive that 4 snakes sh^d have become extinct in Mauritius & survived on Round Island. For a moment I thought that the Mauritius might be the newer island; but the enormous degradation which the outer ring of rocks has undergone flatly contradicts this; & the marine remains on summit of Round Isl^d. indicates the isl^d to be comparatively new; unless indeed they are fossil & extinct marine remains.—⁶ Do tell me what you think. There never was such an enigma.— I rather lean to separate immigration, with of course subsequent modification; some forms, of course, also coming from Mauritius. Speaking of Mauritius, reminds me that I was so much pleased day before yesterday by reading a review of book on Geology of St. Helena, by officer who knew nothing of my hurried observations, but confirms nearly all that I have said on general structure of the Islands & on its marvellous denudation.⁷ The Geology of that island was like a novel.—

Yours affectionately | C. Darwin