Origin of Different Kinds of Adaptations 381 



dividual. The development of an antenna in place of an eye 

 in the shrimp, when the eye stalk is cut off near its base, is 

 another instance of the occurrence of a perfectly constant 

 process, but one that is of no use to the organism. 



When we recall that in some organisms regeneration takes 

 place in almost every part of the body, it does not seem 

 possible that this power could haVe been acquired by selec- 

 tion. And when we find that many internal organs regener- 

 ate, that can rarely or never be injured without the animal 

 perishing, it seems impossible that this can be ascribed to 

 the principle of natural selection. 



It has also been found that if the first two cells of the 

 egg of a number of animals, jellyfish, sea-urchins, salaman- 

 ders, etc., be separated, each will produce an entire animal. 

 In some of these cases it is inconceivable that the process 

 could ever have been acquired through selection, because the 

 cells themselves can be separated only by very special and 

 artificial means. 



These, and other reasons, indicate with certainty that re- 

 generation cannot be explained by the theory of natural 

 selection. 



