My dear Hooker

Many thanks about names of plants, synonyms & male flowers,—all what I wanted.²

I have been glad to see Watson’s letter, & am sorry he is a renegade about Nat. Selection.³ It is, as you say, characteristic with the final fling at you.—⁴ His difficulty about the difference between the two genera of St. Helena Umbellifers, is exactly the same, as what Nägeli has urged in an able pamphet, & who in consequence maintains that there is some unknown innate tendency to progression in all organisms.⁵ I said in letter to him, that of course I could not in the least explain such cases; but that they did not seem to me of overwhelming force, as long as we are quite ignorant of the meaning of such structures,—whether they are of any service to the plants, or inevitable consequences of modifications in other parts.⁶

I cannot understand what Watson means by the “counter balance in nature” to divergent variation.⁷ There is the counter balance of crossing, of which my present work daily leads me to see more & more the efficiency, but I suppose he means something very different. Further I believe variation to be divergent solely because diversified forms can best subsist.— But you will think me a bore.

I enclose half a letter from F. Müller (which please return) for the chance of your liking to see it; though I have doubted much about sending it, as you are so overworked: I imagine the Solanum-like flower is curious.⁸

I heard yesterday to my joy that D Hildebrand has been experimenting on the direct action of pollen on mother-plant with success.⁹ He has also succeeded in making a true graft-hybrid between 2. vars. of Potatoes, in which I failed: I look at this as splendid for Pangenesis, as being strong evidence that bud-reproduction & seminal reproduction do not essentially differ.¹⁰ My book is horribly delayed owing to the accursed Index-maker.¹¹ I have almost forgotten it! Farewell   I am very glad to hear about Willy & Tyndall:¹² I look at it as a sure sign that he will make good progress.—

Yours ever affect | C. Darwin

Do not plague yourself to discuss or enlarge on F. Müllers facts.

When we meet I must enquire a little more about Balanophora.¹³