474 



ANIMAL BIOLOGY 



direct action in the case of plants. The former are induced to 

 react and so adapt themselves, as it were ; while the latter, without 

 a nervous system, are molded directly by their surroundings. And, 

 so Lamarck believed, such changes, somatic in origin — acquired 

 characters — are transmitted to the next generation and bring 

 about the evolution of organisms. (Fig. 309.) 



Through the relative weakness of Lamarck's successors the 

 French school of evolutionists dwindled to practical extinction; 



; ?» 



\ 



- A 

 At 



Fig. 310. — Charles Lyell. 



while in Germany, Goethe (1749-1832), the greatest poet of 

 evolution, and Treviranus (1776-1837) 'brilliantly carried the 

 argument without carrying conviction," for the man and the 

 moment must agree. Then in England the uniformitarian ideas 

 elaborated by Lyell (1797-1875) in his Principles of Geology es- 

 tablished evolution in geology and the way was paved for Charles 

 Darwin (1809-1882) to do the same for the organic world. (Figs. 

 310, 312; pages 373-377.) 



True, "the idea of development saturated the intellectual at- 

 mosphere — nevertheless the elaborate and toilsome labor of think- 

 ing it through for the endless realm of nature was to be done" and 

 Darwin did it in his Origin of Species which appeared in 1859. By 

 his brilliant, scholarly, open-minded, and cautious marshalling of 

 the facts pointing toward the universality of variations and the 



