ORGANIC EVOLUTION 41 



fact that the same general type may be hammered 

 into dozens, or hundreds, or even thousands, of 

 different patterns by the incessant industry of its 

 surroundings, and that the same organic part may 

 be moulded into various implements serving totally 

 different ends by the environmental vicissitudes 

 of time and space. On the hypothesis that the 

 members of each group of animals possessing 

 common characteristics, whether the group be 

 large or small, have sprung from a common 

 ancestry, and that the differences in structure 

 have arisen as a result of differences in environ- 

 ment, the similarities and homologies of structure 

 existing among animals are perfectly intelligible. 

 But on any other supposition they are in- 

 explicable. 



3. Evolution is suggested by the remarkable 

 series of phenomena presented by embryology. 

 There are at least four facts in the developmental 

 history of every creature which can hardly be 

 accounted for on any other supposition than that 

 of organic evolution. 



First, the fact that every animal, above the 

 lowest, individually passes through an evolution 

 between the beginning of its existence and its 

 maturity. Terrestrial beings are not born, like 

 Minerva, full-grown. They grow. They evolve. 

 They commence close down to the very atoms. 

 And from this lowly genesis they rise, through 

 a series of marvellous changes, to that high state 

 of perfection and greatness from which they 

 descend to dissolution. 



