868 PROGRESS OF SCIENCE IN THE CENTURY. 



marvellous bud-like miniature of the adult, it neces- 

 sarily included in its turn the next generation, and 

 this the next — in short all future generations. 

 Germ within germ, in ever smaller miniature, after 

 the fashion of an infinite juggler's box, was the cor- 

 ollary of " emboUementf — logically appended to this 

 theory of preformation and unfolding, — of evolu- 

 tion, as it was then called, in a very different but 

 more literal sense from that in which we now use 

 the word. 



" The whole chapter is a somewhat lamentable one 

 in the history of embryology, and yet it must be noted 

 in fairness that the preformationist doctrine had a well- 

 concealed kernel of truth within its thick husk of 

 error. There is a certain sense in which the whole 

 future organism is potentially and materially implicit 

 in the fertilised egg-cell ; there is a sense in which the 

 germ contains not only the rudiment of the adult 

 organism, but of successive generations as well. But 

 in neither of these senses was preformationism under- 

 stood by any of its upholders." * 



In 1759 Caspar Friedrich Wolff (1733-1794) 

 raised a strong protest against the doctrines and 

 methods of the preformationists. He showed that 

 the egg does not contain a preformed embryo, but 

 that the organs were to he seen being formed. But 

 his vindication of " epigenesis '' against " evolutio " 

 did not win conviction as it ought to have done; 

 indeed it remained for about sixty years without ef- 

 fect. 



In 1817 Christian Pander took up embryological 

 research where Wolff had left it, and worked out the 



*S©e th© writer's Science of Life, 1899, p. 1^1, 



