192 THE DOCTRINE OF DESCENT. 



An objection frequently made against this result of 

 the doctrine of Descent is, that if all are pressing for- 

 ward towards perfection, how is it that, besides the higher, 

 so many lower members of the family are able to main- 

 tain themselves, and how can the lower families hold 

 their own against the higher, in the struggle for exist- 

 ence? In presence of the irrefutable facts of progress, 

 it is enough to point out thg.t the lower forms could and 

 can continue to exist wherever they could find space as 

 well as the other necessaries of life. While they here 

 underwent only slight modifications, elsewhere the need- 

 ful selection led to more profound metamorphoses; and 

 on a subsequent geographical displacement, the newly 

 transformed beings, accustomed to other conditions of ex- 

 istence, were again able to share sea and land with the 

 stationary species. For as diversity is restored now by 

 .selection, and the demands for nutriment and other neces- 

 saries are likewise different, a partial remission in the 

 struggle must take place. 



The preservation of a great many inferior organisms 

 is evidently favoured by the circumstance that just be- 

 cause they are simpler, their propagation is more easily 

 effected. Hence although, especially in limited districts, 

 amid violent competition of superior varieties, countless 

 species must suffer extirpation, yet the struggle for ex- 

 istence and . perfection do not exclude the existence of 

 lower forms. But teleology, as it seems to us, still fails 

 to explain what has been explained by the theory of selec- 

 tion. The retardation of the lower organisms, notwith- 

 standing the internal pressure and the appointed purpose, 

 is incomprehensible. 



But, it is frequently asked, if you will not hear of 



