194 THE PROBLEM OF EVOLUTION 



the remarks in my closing address on the 

 subject of this biogenetic principle. 



Dr. Schmidt-Jena claimed to have proved in a 

 little work published some years ago, that the 

 biogenetic principle was applicable to the, develop- 

 ment of every individual, precisely because it keeps 

 in view both heredity and adaptation. He thought 

 that in the same work he had shown another 

 eminent scientist to have been wrong in assigning 

 another interpretation to this principle. 



This other eminent scientist was no less 

 important a person than Professor Oskar 

 Hertwig, director of the Berlin Institution for 

 Biology and Anatomy. No one can seriously 

 think that Hertwig' s opinions were refuted 

 in the insignificant pamphlet written by 

 Haeckel's assistant. See Her twig's more recent 

 work < Das biogenetische Grundgesetz nach dem 

 heutigen Stande der Biologie ' (The Biogenetic 

 Principle considered in the Light of Modern 

 Research in Biology) (Internationale Wochen- 

 schrift filr Wissenschaft und Technilc, 1907, No. 2, 

 etc.). In my third lecture I used Hertwig's 

 arguments against the biogenetic principle. If 

 his ' other interpretation,' or rather refutation, 

 of the principle is a failure, Dr. Schmidt-Jena 

 would have done well to prove it, and not 

 to expect us to accept his bare assertion. 



