NATURAL SCIENCE IN THE NINETEENTH CENTURY 373 



the current theory of cosmogony the idea of gradual develop- 

 ment or evolution, an ancient idea thenceforward made the 

 keynote of his speculations. Systematic zoology and compara- 

 tive anatomy, the latter already well begun by Hunter in the 

 eighteenth century, were immensely advanced by Cuvier (1769- 

 1832), who however clung tenaciously to the theory of special 

 creation; while Geoffrey St. Hilaire (1772-1844) also a com- 

 parative anatomist, but one whose interests lay rather in the 

 functional than in the anatomical resemblances of the parts of 

 animals, and who is therefore regarded as "the father of homol- 

 ogy" on the whole opposed Cuvier's and favored Lamarck's 

 ideas. His Philosophie anatomique appeared in 1818-1822. 



Nature, said St. Hilaire, has formed all living beings on one plan, 

 essentially the same in principle, but varied in a thousand ways in all 

 the minor parts ; all the differences are only a complication and modi- 

 fication of the same organs. 



This similarity of structure, or homology as it is called, which runs 

 through all animals, was thus first clearly stated by St. Hilaire, and 

 has now been carefully worked out and confirmed. . . . Yet Cuvier 

 opposed it to the last, for his mind was full of another idea which is 

 equally true ; namely, how perfectly each part of an animal is made 

 to fit all the other parts ; and it seemed to him impossible that this 

 could be, unless each part was created expressly for the work it had 

 to do. 



The discussion between the two friends became so animated that 

 all Europe was excited by it. It is said that Goethe, then an old 

 man of eighty-one, meeting a friend, exclaimed, 'Well, what do you 

 think of this great event ? the volcano has burst forth, all is in flames. ' 

 His friend thought he spoke of the French Revolution of July, 1830, 

 which had just occurred, and he answered accordingly. ' You do not 

 understand me,' said Goethe, ' I speak of the discussion between Cuvier 

 and St. Hilaire : the matter is of the highest importance. The 

 method of looking at nature which St. Hilaire has introduced can 

 now never be lost sight of.' Arabella Buckley Fisher. 



The history of zoology in the first half of the nineteenth century 

 is chiefly that of the work of Cuvier, St. Hilaire, Lamarck, Agassiz 

 and their disciples. 



