TRANSLATOR'S PREFACE. 



IN offering to English readers this translation of 

 Professor Weismann's well-known u Studies in the 

 Theory of Descent," the main part of which is 

 devoted to entomological subjects, I . have been 

 actuated by the desire of placing in the hands of 

 English naturalists one of the most complete of 

 recent contributions to the theory of Evolution as 

 applied to the elucidation of certain interesting 

 groups of facts offered by the insect world. 

 Although many, if not most, working naturalists 

 are already familiar with the results of Dr. Weis- 

 mann's researches, of which abstracts have from 

 time to time appeared in English and American 

 scientific journals, I nevertheless believe that a 

 study of the complete work, by enabling the 

 reader to follow closely the detailed lines of 

 reasoning 'and methods of experiment employed 

 by the author, will be found to be of considerable 

 value to those biologists who have not been able 

 to follow the somewhat difficult phraseology of 

 the original. It is not my intention, nor would it 

 be becoming in me to discuss here the merits of 



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