ERASMUS DARWIN. 143 



general philosophy of Nature, as under the opera- 

 tion of natural laws rather than of the supernatural, 

 he himself in the Zoonomia attributes to David 

 Hume. 



Dr. Darwin's theory of the causes of Evolution 

 was not similar to Buffon's, for he nowhere lays 

 stress upon the modifications induced by the direct 

 action of Environment ; on the other hand, he be- 

 lieved that modifications spring from within by the 

 reactions of the organism ; thus he fully anticipated 

 what is now known as the Lamarckian theory, and 

 extended it even further than Lamarck, since he en- 

 dowed plants with sensibility and attributed their 

 evolution to their own efforts towards the attain- 

 ment of certain structures. His view of the origin 

 of adaptations or of design in Nature was thor- 

 oughly naturalistic, believing that adaptations had 

 not been specially created, but that they had been 

 naturally and gradually acquired by powers of de- 

 velopment planted within the original organisms by 

 the Creator. 



In a defence of Lamarck's originality, Quatre- 

 fages mistakenly attributes to Dr. Darwin the theory 

 of an 'inherent perfecting tendency'; but this we 

 find is an entire misconception. Let us, therefore, 

 carefully examine Dr. Darwin's theory as expounded 

 in the chapter ' Generation ' of the Zoonomia. In 

 this chapter he combats Bonnet's doctrine of 

 emboitement, and defends the idea of individual 

 development by successive additions of parts to the 



