2 THE FOUNDATIONS OF THE 'ORIGIN OF SPECIES.' 



theological natural history than with his later views. Thus, 

 in speaking of the birds Synallaxis and Scytalopus (ist edit. 

 p. 353 ; 2nd edit. p. 289), he says: "When rinding, as in 

 this case, any animal which seems to play so insignificant 

 a part in the great scheme of nature, one is apt to wonder 

 why a distinct species should have been created." 



A comparison of the two editions of the ' Journal ' is in- 

 structive, as giving some idea of the development of his 

 views on evolution. It does not give us a true index of 

 the mass of conjecture which was taking shape in his mind, 

 but it shows us that he felt sure enough of the truth of his 

 belief to allow a stronger tinge of evolution to appear in 

 the second edition. He has mentioned in the Autobiography 

 (p. 83), that it was not until he read Malthus that he got a 

 clear view of the potency of natural selection. This was in 

 1838 a year after he finished the first edition (it was not 

 published until 1839), and seven years before the second edition 

 was written (1845). Thus the turning-point in the formation 

 of his theory took place between the writing of the two 

 editions. 



I will first give a few passages which are practically the 

 same in the two editions, and which are, therefore, chiefly of 

 interest as illustrating his frame of mind in 1837. 



The case of the two species of Molothrus (ist edit. p. 61 ; 

 2nd edit. p. 53) must have been one of the earliest instances 

 noticed by him of the existence of representative species 

 a phenomenon which we know ('Autobiography,' p. 8^,) struck 

 him deeply. The discussion on introduced animals (ist edit. 

 p. 139 ; 2nd edit. p. 120) shows how much he was impressed 

 by the complicated interdependence of the inhabitants of a 

 given area. 



An analogous point of view is given in the discussion 

 (ist edit. p. 98 ; 2nd edit. p. 85) of the mistaken belief that 

 large animals require, for their support, a luxuriant vegeta- 

 tion ; the incorrectness of this view is illustrated by the com- 



