350 Darwm and Geology 



book on Transmutation of Species. Had been greatly struck from 

 about the month of previous March on character of South American 

 fossils...^" 



The second volume of Ly ell's Principles of Geology was published 

 in January, 1832, and Darwin's copy (like that of the other two 

 volumes, in a sadly dilapidated condition from constant use) has 

 in it the inscription, "Charles Darwin, Monte Video. Nov. 1832." 

 As everyone knows, Darwin in dedicating the second edition of his 

 Journal of the Voyage to Lyell declared, " the chief part of whatever 

 scientific merit this journal and the other works of the author 

 may possess, has been derived from studying the well-known and 

 admirable Principles of Geology." 



In the first chapter of this second volume of the Principles, Lyell 

 insists on the importance of the species question to the geologist, but 

 goes on to point out the difficulty of accepting the only serious 

 attempt at a transmutation theory which had up to that time 

 appeared — that of Lamarck. In subsequent chapters he discusses 

 the questions of the modification and variability of species, of 

 hybridity, and of the geographical distribution of plants and animals. 

 He then gives vivid pictures of the struggle for existence, ever going 

 on between various species, and of the causes which lead to their 

 extinction — not by overwhelming catastrophies, but by the silent 

 and almost unobserved action of natural causes. This leads him to 

 consider theories with regard to the introduction of new species, 

 and, rejecting the fanciful notions of "centres or foci of creation," 

 he argues strongly in favour of the view, as most reconcileable with 

 observed facts, that " each species may have had its origin in a single 

 pair, or individual, where an individual was sufficient, and species may 

 have been created in succession at such times and in such places 

 as to enable them to multiply and endure for an appointed period, 

 and occupy an appointed space on the globe ^." 



1 L. L. I. p. 276. 



* Frinciples of Geology, Vol. ii. (1st edit. 1832), p. 124. We now know, as has been 

 so well pointed out by Huxley, that Lyell, as early as 1827, was prepared to accept 

 the doctrine of the transmutation of species. In that year he wrote to Mantell, "What 

 changes species may really undergo 1 How impossible will it be to distinguish and lay 

 down a line, beyond which some of the so-called extinct species may have never passed 

 into recent ones " (Lyell's Life and Letters, Vol. i. p. 168). To Sir John Herschel in 1836, 

 he wrote, "In regard to the origination of new species, I am very glad to find that you 

 think it probable that it may be carried on through the intervention of intermediate 

 causes. I left this rather to be inferred, not thinking it worth while to offend a certain 

 class of persons by embodying in words what would only be a speculation" {Ibid. p. 4G7). 

 He expressed the same views to Whewell in 1837 (Ibid. Vol. ii. p. 5), and to Sedgwick 

 (Ibid. Vol. II. p. 36) to whom he says, of "the theory, that the creation of new species is 

 going on at the present day" — "I really entertain it," but "I have studiously avoided 

 laying the doctrine down dogmatically as capable of proof" (see Huxley in L. L. u. 

 pp. 100—195). 



