PREFACE 



It was with great pleasure that I accepted the invitation of the 

 Editor of the Pergamon Press Zoological Series to publish in 

 book form and in English, as an international language, the 

 results of my research on the Cnidaria, the interpretations of 

 this research, and the final effects of these interpretations. I was 

 all the more pleased with this invitation because my first gen- 

 eral study of this problem appeared 17 years ago during the 

 turmoils of the Second World War, when I tried to save the 

 existence of the Slovene Academy of Arts and Sciences at 

 Ljubljana which was threatened by the occupying powers. 



My book. The Turhellarian Theory of the Cnidaria ; The Phylogeny 

 of the Cnidaria and Their Position in the Animal System was publish- 

 ed in a Slav language, in the language of the small yet pro- 

 gressive nation of Slovenes. Added to this text was a detailed 

 summary written in an international language which could help 

 various scholars to get acquainted with the contents of the 

 book. The summary was written in German because I myself 

 completed my studies at Vienna University. 



Since the publication of this book many new elements have 

 become known in the field of biology, and above all in zoology. 

 Neither have I ceased with my studies: a whole series of special 

 papers have been written by me in the meantime which are 

 closely connected with problems that had only been touched 

 on in the book. In the international literature there were a 

 number of reactions to my book and to my subsequent shorter 

 publications; this was especcially true for my article which ap- 

 peared in the American review. Systematic Zoology. The publica- 

 tion of this article was made possible due to the generous help 

 of an excellent translator, Piofessor A. Petrunkewitch. 

 American and the English zoologists have shown particularly 



vil 



