Will finish last chapter (except recapitulation) tomorrow.
Pleased with JDH's response to geographical distribution chapter;
CD disagrees with Lyell's view that glacial epoch is connected with position of continents.
Down Bromley Kent.
My dear Hooker
I am pleased at what you say of my Ch.— You have not attacked it nearly so much as I feared you would. You do not seem to have detected many errors.— It was nearly all written from memory, & hence I was particularly fearful; it would have been better, if the whole had first been carefully written out, & abstracted afterwards.
I look at it as morally certain that it must include much error in some of its general views.— I will just run over a few points in your note; but do not trouble yourself to reply, without you have something important to say.—
I grieve to say that I feel compelled to disbelieve in the Lyellian view that Glacial Epoch is connected with position of continents: I have not thought myself compelled to say anything on this head, more than on cause of heat at Melville Isd in Carboniferous period: I think we know nothing on subject.—
I do not feel quite sure of entire revolution of continents & seas even during Chalk Period: the shores of Chalk Sea in Europe can be partly traced.
I do not see why the exclusively Australian forms could not have been manufactured in Australia: you must have here some meaning which I cannot fathom. I quite agree how strange that no Australian forms got to Europe: but I do not see why most Australian plants shd have been pushed into the sea.
Many Thanks for caution about seeds of Trees: I was quoting by memory from A. De Candolle.— I will strike out passage.—
About Cryptogamic plants, & physical conditions I cannot remember anything on the checks to their increase, ie on their general relations of life.—
I daresay you will make excellent use of “wet & dry” in distribution: it is beyond my tether.
I shall be very curious to see your Essay.
I shd like to know whether the case of Endemic Bats in Islands struck you: it has me especially; perhaps too strongly.
With hearty thanks | Ever yours | C. Darwin
You cannot tell what a relief it has been to me, your looking over this chapter, as I felt very shaky on it.—
I shall tomorrow finish my last chapter, (except a Recapitulation) on Affinities, Homologies, Embryology &c & the facts seem to me to come out very strong for mutability of species.— I have been much interested in working out this chapter. I shall now, thank God, begin looking over old first chapters for press.— But my health is now so very poor, that even this will take me long.—
- f1 2432.f1CD had sent Hooker the manuscript on geographical distribution intended for his forthcoming ‘abstract’ (Origin, pp. 346–410). Hooker's comments have not been found. See letters to J. D. Hooker, 2 March , 5 [March 1859], and 11 March .
- f2 2432.f2Although CD had previously written out a long section of his argument pertaining to geographical distribution and a former cold period (Natural selection, pp. 534–66), which Hooker had read in 1856, he had not written up the material on the means of dispersal nor his views on land-bridges and oceanic islands. These sections, as he states in the letter, were first composed for Origin.
- f3 2432.f3Charles Lyell's view that the relative positions of land and sea were the cause of major climatic changes had been the central argument of his Principles of geology. See C. Lyell 1830–3 and Ospovat 1977.
- f4 2432.f4The existence of tropical and subtropical fossil plants in the Carboniferous formations of Melville Island (in the Arctic Circle) was not discussed in Origin. CD's point that changes in climate were not necessarily due to the elevation or subsidence of nearby continents was, however, mentioned (Origin, pp. 356–8).
- f5 2432.f5CD refers to Hooker's remarks concerning CD's discussion of migration during the cold period in Origin, pp. 379–82.
- f6 2432.f6It is not known what point Hooker made about the seeds of trees, but CD discussed Alphonse de Candolle's views on the restricted geographical range of trees in Origin, p. 392.
- f7 2432.f7Possibly a reference to CD's statement in Origin, p. 406, that organisms low in the scale of nature had a better chance of ranging widely.
- f8 2432.f8Hooker 1859.
- f9 2432.f9See Origin, pp. 394–5.
- f10 2432.f10See ‘Journal’ (Appendix II).