THE DOCTRINE OF PROGRESSIVE DEVELOPMENT. 271 



or more detailed analysis of the views put forward in this 

 striking work. Our purpose will be sufficiently served by 

 a brief notice as to the views of the author on the special 

 question of the origin of ' species ' among animals. 



As regards the question of the fixity or mutability of 

 'species,' the author of the 'Vestiges' fully accepted 

 Lamarck's views, in so far as he maintained that species 

 are not invariable or constant. 'It is difficult,' he 

 remarks, ' to regard the idea of species or specific distinc- 

 tion as descriptive of a fact in nature ; it must be held as 

 merely applicable to certain appearances presented, perhaps 

 transiently, to our notice. The history of the question 

 seems to be this. Naturalists, starting with a limited fund 

 of observation mainly, indeed, consisting of the remark 

 which the most superficial observation supplies, that like 

 usually produces like lay it down as an axiom that 

 species is a determined thing. In a little time, certain 

 modifiabilities are observed. To maintain the axiom 

 intact, these are called varieties. Afterwards, much 

 greater variabilities are witnessed, even to the dissolution 

 of genera among the cryptogams and cereals, and the 

 community of algae and fungi water and land plants. 

 Still, to keep the axiom whole, these are held in doubt, or 

 relegated to a place in the elastic region of the varieties. 

 Such is the stage which we have now attained. But this is 

 a process the reverse of philosophical : it is to start with a 

 theory, and then make the facts succumb to it. Were the 

 process reversed, and the facts taken first, we should 

 see that a great modifiability exists in organic nature, 

 especially in the humbler departments of the two king- 

 doms. And seeing that this modifiability presents itself 



