ORGANIC E VOL UTION. 1 7 



I. 



THE ARGUMENT FROM CLASSIFICATION. 



I SHALL first take the argument from classifica- 

 tion. Naturalists find that all species of plants 

 and animals present among themselves structural 

 affinities. According as these structural affinities 

 are more or less pronounced, the various species 

 are classified under genera, orders, families, classes, 

 sub-kingdoms, and kingdoms. Now in such a 

 classification it is found impossible to place all 

 the species in a linear series, according to the 

 grade of their organization. For instance, we 

 cannot say that a wolf is more highly organized 

 than a fox or a jackal ; we can only say that 



C 



