65 



CHAPTER XIII. 



INFERENTIAL. 



GUIDED by the clue presented in the phases 

 of the embryo and in fragmentary organs, 

 we have learned to decipher the open secret 

 of evolution, but these phenomena seem to 

 have a wider and far higher significance 

 than merely to disclose its path. 



Consider for a moment the transforma- 

 tions and adaptations of organs that take 

 place in evolving the organisation of a new 

 type from that of its antecessor, as revealed, 

 for example, in the embryos of the calf and 

 of the whale. The upper incisor teeth of 

 the antecessor begin to be developed in the 

 embryo of the calf, but as teeth are not 

 suitable for the conditions of its life, their 

 growth is arrested ; the incipient teeth will, 

 however, form a satisfactory base for the 

 hard pad, suitable for cropping grass, that 

 is to cover them, and they are utilised in 

 the new structure. 



E 



