112 NATIONAL TRENDS IN BIOLOGY 



words : Vitalism is considered very important because "it 

 is the only biological influence on practical life — that is, 

 the theory of vitalism — for it not only liberates the mind 

 from materialism in every respect, but also has a decided 

 effect on morality — on the conduct of man." 

 The great names mentioned are : 



1. Thienemann who, with his school, did a vast amount 

 of research, as did Kofoid in the United States, on the 

 reciprocal influence of the organism to its environment ; 



2. William Roux, whose interesting separation of the 

 growing cells in the newly developing embryo inaugurated 

 a discussion which formed the impetus for much of our 

 work in modern experimental embryology ; 



3. Hans Driesch, whose really remarkable work in em- 

 bryology and regeneration brought about the parting of 

 the ways for the modern schools of mechanism and 

 vitalism ; 



4. F. Alverdes, whose Tier Soziologie is a sequel to 

 Trotter's Instincts of the Herd in England; 



5. D. Keilin, now in England, whose discovery of cyto- 

 chrome is mentioned under workers in the British Isles ; 



6. K. von Frisch, whose explanation of the way honey- 

 bees let others in the hive know of their discovery of 

 nectar is of exceptional interest ; 



7. R. Goldschmidt, whose metabolic theory of sex de- 

 termination is of outstanding prominence just now. 



And here are other names mentioned: (8) Bern, (9) 



