182 THE MAIN CURRENTS OF ZOOLOGY 



organic evolution, is to be credited in its inception to 

 the French (Lamarck) and the English (Charles 

 Darwin) . This is probably the greatest philosophical 

 contribution of the nineteenth century. After it was 

 well under way it was taken up by scholars of differ- 

 ent nationalities. Weismann, the German, De Vries, 

 the Hollander, have made notable contributions, and, 

 in America, Cope and others brought forward new 

 aspects of Lamarckism and established the school of 

 Neo-Lamarckism. 



To the genius of Pasteur more than to any other 

 worker we owe the basis of the germ-theory of 

 disease with its concomitants as antitoxins, serum 

 injections and vaccines. The Englishman, Lister, 

 applied these to surgery and the German, Robert 

 Koch, (a student of Ferdinand Cohn), established 

 bacteriology (to which these matters belong) as an 

 independent science. 



The discovery of protoplasm is credited to the 

 Frenchman Dujardin, but the great elaboration of 

 the idea to Max Schultze, the German. 



The cell-theory is a product of German scholar- 

 ship Schleiden and Schwann being founders and 

 Schultze developer of this important conception. 



In the experimental study of heredity, while the 



