MODERN SCIENCE. 131 



Thus, proceeding further than Buffon, Erasmus Darwin, 

 Goethe, who had only asserted the principle, Lamarck 

 systematically and scientifically laid down the great problem 

 of the variability of species for the first time, and thereby laid 

 the foundation of the LAW OF BIOLOGICAL EVOLUTION, by 

 demonstrating the alteration of types man included, for he 

 also enunciated the doctrine, first amongst biologists, that 

 man is the descendant of an ape-like ancestor. The essen- 

 tially original element he brought into science was, let it be 

 remembered, not the evolutionary idea, but the idea that law 

 presides over every process of nature, and hence obtains in 

 biology as in all else. 



17721844. Geoffrey St. Hilaire (Etienne), believing 

 like Lamarck in the MUTABILITY OF SPECIES, demonstrated 

 the unity of plan of the animal kingdom, and pointed 

 out its branching off into innumerable divisions from a 

 central stream. As a matter of fact, he believed all species 

 to be derived by modification from one or several primitive 

 types (1795). He was, like Buffon, Lamarck, and others, an 

 evolutionist. Cuvier held a contrary view. He thought that 

 each species and variety had been separately created and 

 gifted with special organs to meet its wants. And as creation 

 had left them, so they were now. St. Hilaire held that 

 " Nature 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 modification of the same organs." And this HOMOLOGY 

 (similarity of structure) runs through all animals, so that the 

 leg of a horse, a lion, an ox, the wing of the bat, the paddle 

 of a porpoise, the hand of man are the same organs made up 

 of the same bones these being merely altered to meet different 

 purposes. This great principle was demonstrated by St. 

 Hilaire, but it has been fully worked out since by Darwin, 

 Wallace, Haeckel, and others. The divergence of conclusions 

 between Cuvier and Geoffrey St. Hilaire was one which in- 

 terested and stirred up the whole scientific world for a whole 

 generation. His son (Isidore) was a great authority on 

 variability and correlation. 



1779 i SS 1 - Oken was the first to suggest the theory of 



K 2 



