24 THE TRANSFORMATIONS OF THE ANIMAL WORLD 



taneous generation, in the creative powers of terres- 

 trial mud, and in the birth of monstrous and chimeri- 

 cal beings, that it would be better to abstain from 

 drawing from oblivion these works of pure imagina- 

 tion. 



We ought to be nearly as severe with the natura- 

 list philosophers of the Renaissance and of the 

 eighteenth century Bacon, Pascal, Charles Bonnet, 

 Maillet, Maupertuis, and Kant, with whom the 

 transformist idea vaguely disentangles itself from 

 the conceptions relating to the spontaneous appari- 

 tion of germs or of animal species. 



Oken, Goethe, and Buffon bring to the study of 

 the transformation of living beings their solid 

 qualities of observers of nature, and lead the ques- 

 tion into a more precise and fruitful path. Goethe, 

 following Oken, dwells on the repetition and on the 

 metamorphosis of organs. Among vegetables the 

 leaf transforms itself into the coverings and organs 

 of the flower ; in the higher animals the spine 

 becomes modified, and enlarges so as to form the 

 cranium. The primitive forms of animals and of 

 plants thus become, little by little, more compli- 

 cated by the repetition and differentiation of like 

 parts. Buffon already held very exact notions on 

 the succession of beings at the various Epoques de la 

 Nature, the title of one of his most important works. 



The early seas nourished numerous forms of 

 molluscs, crustaceans, and fishes of a type now 

 vanished. These animal forms have been again and 

 again renewed, some becoming more perfect, others 

 degenerating ; these last, being less perfect and less 

 active, have yielded to the first-named, and have 



