To J. D. Hooker   18 March [1862]¹

My dear Hooker

I am astonished at your larkiness in going to Walcot; I wish it had been Powis Castle, which, as far as I remember, is very grand. I saw your host, as a child; & have heard since that he is reckoned stiff & proud, but very respectable.—²

Your letter discusses lots of interesting subjects,³ & I am very glad you have sent for your letter to Bates.⁴ What do you mean by “individual plant”? I fancied a bud lived only a year & you could hardly expect any change, in that time; but if you call a tree or plant an individual, you have sporting buds. Perhaps you mean that the whole tree does not change. Tulips in “breaking” change. Fruit—seems certainly affected by the stock. I think I have got cases of slight changes in alpine plants transplanted. All these subjects have rather gone out of my head owing to Orchids; but I shall soon have to enter on them in earnest, when I come again to my volume on Variation under Domestication.⁵ In the life time of an animal you would, I think, find it very difficult to show effects of external conditions on animals, more than shade & light, good & bad soil, produce on a plants.⁶

You speak of “an inherent tendency to vary wholly independent of physical conditions”. This is a very simple way of putting the case (as D^r. Prosper Lucas also puts it);⁷ but two great classes of facts make me think that all variability is due to changes in the condition of life. (1) that there is more variability & more monstrosities (& these graduate into each other) under unnatural domestic conditions, than under nature. And secondly that changed conditions affect in an especial manner the reproductive organs,—those organs which are to produce a new being.— But why one seedling out of thousands presents some new characters transcends the wildest powers of conjecture. It was in this sense that I spoke of “climate, &c” possibly producing without selection a hooked seed; or any not great variation.⁸ I have for years & years been fighting with myself not to attribute too much to Nat. selection,—to attribute something to direct action of conditions; & perhaps I have too much conquered my tendency to lay hardly any stress on conditions of life. I am not shaken about “saltus”;⁹ I did not write without going pretty carefully into all the cases of normal structure in animals resembling monstrosities which appear per saltus.—

I saw about Heer, & thought of you; but may not Lowe be wrong?¹⁰ I shall be so glad to see you here at Easter, if you are able to come; if Willy is at home, why not bring him?¹¹ this is Emma’s message as well as mine; but perhaps he will be at school.— We have been very anxious for 6 weeks about our boy Horace, who three or four times a day has spasmodic attacks, something like Chorea, yet different.¹² Our country Doctor thinks it certainly caused only by irritation in alimentary canal;¹³ but I can see that Sir H. Holland thinks it serious.¹⁴ All that one can do, is to hope

Farewell my dear old friend | C. Darwin