268 SCIENCE AND PHILOSOPHY OF THE ORGANISM 



able to assume that all the ancestors of our Triton must 

 have lost one leg, or more correctly, that only those of 

 them survived which had lost one ! Otherwise not all 

 newts at the present day could possess the faculty of 

 regeneration ! But a second absurdity follows the first 

 one ; out of the ancestors of our newt, which survived the 

 others by reason of having lost one of their legs, there were 

 selected only those which showed at least a very small amount 

 of healing of their wound. It must be granted that such a 

 step in the process of selection, taken by itself, would not 

 at all seem to be impossible ; since healing of wounds 

 protects the animals against infection. But the process 

 continues. In every succeeding stage of it there must have 

 survived only those individuals which formed just a little 

 more of granulative tissue than did the rest : though 

 neither they themselves nor the rest could use the leg, 

 which indeed was not present ! That is the second absurdity 

 we meet in our attempt at a Darwinian explanation of the 

 faculty of regeneration ; but I believe the first one alone 

 was sufficient. 



If we were to study the " selection " of the faculty of 

 one of the isolated blastomeres of the egg of the sea-urchin 

 to form a whole larva only of smaller size, the absurdities 

 would increase. At the very beginning we should encounter 

 the absurdity, that of all the individuals there survived 

 only those which were not whole but half; for all sea- 

 urchins are capable of the ontogenetical restitution in 

 question, all of their ancestors therefore must have acquired 

 it, and they could do that only if they became halved at 

 first by some accident during early embryology. But we 

 shall not insist any further on this instance, for it would 



