PART IV 

 THE EVOLUTION OF ANIMAL LIFE 



CHAPTER XVII 



THE EVIDENCES OF EVOLUTION 



1. The idea of evolution 2. Arguments for evolution : 

 Physiological, Morphological, Historical. 



WE observe animals in their native haunts, and study 

 their growth, their maturity, their loves, their struggles, 

 and their death ; we collect, name, preserve, and classify 

 them ; we analyse them with various instruments and 

 get to know their organs, tissues, and cells ; we go back 

 upon their life and inquire into the secret working of their 

 innermost parts ; \ve ransack the rocks for the remains 

 of those animals which lived ages ago upon the earth ; 

 we watch how the chick is formed within the egg, and yet 

 we are not satisfied. We seem to hear snatches of music 

 which we cannot combine. We seek some unifying idea, 

 some conception of the manner in which the world of life 

 has become what it is. 



1. The Idea of Evolution. We do not dream now, 

 as men dreamed once, that all has been as it is since all 

 emerged from the mist of an unthinkable beginning ; nor 

 can we believe now, as men believed once, that all came 

 into its present state of being by a flash of Almighty volition. 

 Thus Erasmus Darwin (1794), speaking of Hume, says 

 ' he concluded that the world itself might have been 

 generated rather than created ; that it might have been 

 gradually produced from very small beginnings, increasing 



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