To J. D. Hooker   6 May [1858]

My dear Hooker

What a striking fact about the willows; but I do not see how it is a “rasper” at least for me; for my notion is that plants common to America & Europe travelled over land, when climate was warmer than now a little before Glacial epoch.—¹ But to business.

I send by this post my M.S. on “commonness”, “range” & “Variation” of species in large & small genera.—² You have undertaken a horrid job in so very kindly offering to read it & I thank you warmly.— I have just corrected the copy & am disappointed in finding how tough & obscure it is; but I cannot make it clearer, & at present I loathe the very sight of it. The style of course requires further correction, & if published I must try, but as yet see not how, to make it clearer.

If not lost, please glance at the way, in which I before asked you to consider the subject;³ please read the Notes pinned on back of Pages.—⁴ There is one query about Urticaceæ & We؟ddell?s.—⁵

If you have much to say & can have patience to consider whole subject, I would meet you in London on Phil. Club day, so as to save you trouble of writing.—⁶ For Heavens sake, you stern & awful judge & sceptic, remember that my conclusions may be true notwithstanding that Botanists may have recorded more vars. in large than in small genera.— It seems to me a mere balancing of probabilities.— Again I thank you most sincerely, but I fear you will find it a horrid job.—

Ever yours | C. Darwin

As usual Hydropathy has made a man of me for a short time: I hope the Sea will do M^rs. Hooker much good.—

P.S | I had such a piece of luck at Moor Park: I found the rare Slave-making Ant, & saw the little black niggers in their Master’s nests.—⁷