368 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 " emboitement" 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 pref ormationist 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 Eriedrich Wolff (1733-1794:) 

 raised a strong protest against the doctrines and 

 methods of the prefonnationists. He showed that 

 the egg does not contain a preformed embryo, but 

 that the organs were to be seen being formed. But 

 his vindication of "epigeneais" against "evolution" 

 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 



*See the writer's Science of Life, 1899, p. 121. 



