To J. D. Hooker [21 March 1857]
– in regard to species, & then all is horrid fog.— You told me that you could lend me Drege’s work or list on the distribution of the Cape Plants1 (not the paper in the Flora,2 which I know) & I shd be particularly obliged for it within a week & I will keep it not more than a fortnight. Will you send it per Post, & let me pay postage. I want to see whether there are materials to work out range of the species in large genera contrasted with those in small genera.— A. De C. has done it for families,3 but as these will include small & large genera, I think this is not the right way. Asa Gray took genera as I asked him & the result was as it shd be, for as Agassiz says, nature never lies.4
I am amusing myself with several little experiments; I have now got a little weed garden & am marking each seedling as it appears, to see at what time of life they suffer most.—5
I congratulate you on having done so much of the Indian Flora, & am astounded how you possibly could have made out 7000 species & ticketed 15000 species.6 I would not have done such work for a guinea a specimen! Such materials will give some splendid general results.— I envy your power of work & noble zeal.—
Some time ago you told me of two reputed species of Thistle, which in the Himalaya, alone, were blended by a perfect series of intermediate forms: some time I shd be very glad to have particulars briefly, & be allowed to quote; I shd like to know whether both the distinct forms grew mingled with the intermediates.
My dear Hooker | Your’s affectionately | C. Darwin
Ranges of species in large vs small genera: Asa Gray’s compilation fits CD’s expectation.
CD studies seedling mortality in his weed garden.
JDH’s work on Indian flora.
Please cite as
Darwin Correspondence Project, “Letter no. 2067,” accessed on 26 August 2016, http://www.darwinproject.ac.uk/DCP-LETT-2067