REPRODUCTION 105 



This is not the case in the process of develop- 

 ment, for the egg possesses a power by which 

 it is absolutely able to modify the course of 

 nature and to arrive at its destination by a 

 road never previously utilised by any egg. 

 Some will reply that this is because the egg is 

 adapted to reach a certain end and, therefore, 

 does reach it. We shall have to consider more 

 carefully the queston of adaptations in a suc- 

 ceeding chapter but here it may at once be 

 said that to explain or attempt to explain the 

 occurrences which are about to be described 

 by that method is really tantamount to ex- 

 plaining them by saying that what is intended 

 to happen must happen, which does not help 

 us very far upon our road. 



And even those who hold to the most 

 mechanical idea of adaptations, if such a word 

 has any real meaning in the mechanical philo- 

 sophy (which may be doubted), even these will 

 be forced to admit that adaptations in nature 

 would naturally be provided for purposes 

 likely to occur in the ordinary course of nature. 

 Now steps in the experimental embryologist, 

 and, with all the resources provided for him 

 by science, he sets himself to work to modify 

 and distort the course of nature. What is the 

 result ? Within limits and wonderfully wide 

 limits, the egg gets the better of him, for it 



