IGNORABIMUS ET RESTRINGAMUR. 117 



who in 1 7 5 9 first detected the nature of the individual 

 processes of development in the animal ovum, and 

 founded on it his observations in his " Theoria Genera- 

 tiones," which marked an epoch in biological science. 

 The Berlin savants, full of the prevailing prejudices, 

 so contrived at that time that Wolff never once could 

 obtain the permission which he craved, to lecture 

 publicly, and in consequence found himself compelled 

 to retire to St. Petersburg for the sake of peace. And 

 yet in that instance there was no question of a 

 "theory" properly so-called. For the fundamental 

 theory of generation the " theory of epigenesis " as 

 propounded by "Wolff was nothing more than a simple, 

 general exposition of embryological facts which he had 

 been the first to recognise, and of whose truth every 

 one might convince himself by direct observation. In 

 spite of this, for another half century, the predominant 

 error of the " Preformation-theory " continued to be 

 universally accepted the ludicrous and nonsensical 

 doctrine, supported by the authority of Haller, that all 

 the successive generations of animals exist pre-con- 

 ceived and enclosed one within the other, and that no 

 individual development ever takes place ! Nulla est 

 epigenesis I (Compare my " Evolution of Man," vol. i. 



P- 31.) 



But it would appear that it is the fate of that most 



