416 THE EVOLUTION OF LIFE. 



Either the multitudinous kinds of organisms which now exist, 

 and the far more multitudinous kinds which have existed 

 during past geologic eras, have been from time to time separ- 

 ately made; or they have arisen by insensible steps, through 

 actions such as we see habitually going on. Both hypotheses 

 imply a Cause. The last, certainly as much as the first, 

 recognizes this Cause as inscrutable. The point at issue is, 

 how this inscrutable Cause has worked in the production of 

 living forms. This point, if it is to be decided at all, is to be 

 decided only by examination of evidence. Let us inquire 

 which of these antagonist hypotheses is most congruous with 

 established facts. 



