GENERAL CONCLUSIONS. 799 



§ 426. How works the Derivative Law ? — The guesses made 

 by those who have given the rein to the imaginative faculty in 



Natural Selection to have done something toward that end,' to wit, the 'origin of 

 species,' proceeds to remark: 'It is surprising that this admission should not have 

 been made earlier, as Prof. Owen now believes that he promulgated the theory of 

 Natural Selection in a passage read before the Zoological Society, in February, 1850 

 (Trans, vol. iv. p. 15).' 



The reason assigned for this assertion is a paragraph in my letter to the ' London 

 Review,' May 5, 1866, p. 516, which letter Mr. Darwin represents as an expres- 

 sion of my belief ' that I promulgated the theory of Natural Selection in a pas- 

 sage read before the Zoological Society, in February, 1850.' The passage which 

 Mr. Darwin quotes is as follows: — " No naturalist can dissent from the truth of your 

 perception of the essential identity of the passage cited with the basis of that (the 

 so-called Darwinian) theory, the power, viz. of species to accommodate themselves or 

 bow to the influences of surrounding circumstances." My ground for assuming the 

 recognition of ' the power of species to accommodate themselves or bow to the influence 

 of surrounding circumstances ' to be the basis of the ' so-called Darwinian theory,' 

 was, the definition of that theory given by the author in the title-page of the work 

 ' On the Origin of Species by means of Natural Selection.' For, the words ' Natural 

 Selection ' not being likely, of themselves, to suggest the mode of origin of species, the 

 author adds the following definition of his meaning : ' or, the preservation of favoured 

 races in the struggle for life.' 



Now, although in the perusal of the work so entitled I found many other previously 

 propounded grounds of a belief as to the origin of species — as, e. g. ' volition or endea- 

 vour to act in a given way,' p. 184, ' homology,' p. 434, 'irrelative repetition,' p. 149, 

 1 geological time,' p. 282, ' successive extinction of species,' p. 312, 'indications of older 

 or earlier species having a more embryonal or generalised structure than their successors,' 

 p. 338, &c, — all of which had seemed to me to be better evidences of a genetic succession 

 of species than the one ground set forth in the title-page — yet, being so set forth, it was 

 due to the author to refer to it as ' the basis ' of his theory. If reference be now made 

 to the 'Zoological Transactions,' vol.iv. p. 15 (February, 1850), or to 'Preface' (vol. i.) 

 p. xxxiv., it will be seen that I exemplify the principle of the preservation of the favoured 

 race, in the circumstances of the struggle described, including seasonal extremes, adap- 

 tation to kinds of food, generative powers, introduction of enemies, &c, by such cha- 

 racters of species as those of size : — ' If a dry season be gradually prolonged, the large 

 Mammal will suffer from the drought sooner than the small one ; if such alteration of 

 climate affect the quantity of vegetable food, the bulky Herbivore will first feel the 

 effects of stinted nourishment ; if new enemies are introduced, the large and conspicuous 

 quadruped or bird will fall a prey, whilst the smaller species conceal themselves and 

 escape. Smaller animals are usually, also, more prolific than larger ones.' It will be 

 admitted, I may believe, that, in view (in 1850) of the question of extinction by 

 cataclysm, or by surrounding influences, not more extraordinary, for example, than 

 extreme season (heat, cold, rain, drought, as part of the ordinary Laws of Climate), 

 the operation of such influences in the preservation of some races and the extirpation 

 of others could scarcely be more explicitly propounded. And this principle of victory 

 or defeat in the ' contest with surrounding agencies ' is set forth in Mr. Darwin's title- 

 page as the basis of his theory of Natural Selection. Then, when a reviewer, ignorant 

 of, or ignoring, the relative dates of promulgation of such basis, quotes me as adopting 

 Mr. Darwin's theory, and when I point out the transposition of the dates of that 

 theory and of my enunciation of its basis, Mr. Darwin turns upon me and writes, in 

 1866 : ' Mr. Owen now believes that he promulgated the theory of Natural Selection,' 

 and adds, ' this belief in Prof. Owen that he thus gave to the world the theory of 

 Natural Selection will surprise all who are acquainted with the several passages of his 

 works,' &c. (p. xviii.). But all that Mr. Darwin gives in support of this statement 



