The Origin of Species 313 



past generation. These Neo-Lamarckians have ar- 

 rayed themselves against the Neo-Darwinians, who 

 claim that they, and they alone, are truly ortho- 

 dox. Much ingenuity has been expended in the 

 elaboration of theories which shall prove one side 

 or the other, but it must be confessed that to the 

 outsider these theories often savor more of meta- 

 physics than of natural science. For an admirable 

 summary of the present status of evolutionary the- 

 ories the reader may consult Professor Kellogg's 

 recent work, " Darwinism To-day." 



Let us briefly examine the testimony of plants 

 as to the method by which new forms arise, 

 or if you will, the methods of the origin of species. 



Natural Selection. The essence of the Dar- 

 winian theory is that species have arisen by natural 

 selection, as the result of the struggle for existence 

 necessitated by the fact that there are always many 

 more individuals produced than can possibly come 

 to maturity. Darwin believed that natural selec- 

 tion acted upon the slight fluctuating variations 

 which constantly occur in all species, but he also rec- 

 ognized the possibility of new species being started 

 by discontinuous variations, or sports, although he 

 considered these of secondary importance in species 

 forming. That natural selection does act is easily 

 enough demonstrated by direct observation; but it 

 is not so easy to show why certain individuals sur- 

 vive while others perish. While in a general way 

 it may be assumed that the fittest survive, this does 



