MISCELLANEOUS OBJECTIONS. 187 



CHAPTER VII. 



MISCELLANEOUS OBJECTIONS TO THE THEORY OP NATURAL 



SELECTION. 



Longevity — Modifications not necessarily Simultaneous — Modifica- 

 tions apparently of no Direct Service — Progressive Development — 

 Characters of Small Functional Importance, the most Constant — 

 Supposed Incompetence of Natural Selection to account for the 

 Incipient Stages of Useful Structures — Causes which interfere 

 with the Acquisition through Natural Selection of Useful Struc- 

 tures — Gradations of Structure with Changed Functions — Widely 

 Different Organs in Members of the Same Class, developed from 

 One and the Same Source — Reasons for disbelieving in Great and 

 Abrupt Modifications. 



I will devote this chapter to the consideration of various 

 miscellaneous objections which have been advanced against 

 my views, as some of the previous discussions may thus be 

 made clearer ; but it would be useless to discuss all of them, 

 as many have been made by writers who have not taken the 

 trouble to understand the subject. Thus a distinguished 

 German naturalist has asserted that the weakest part of my 

 theory is, that I consider all organic beings as imperfect : 

 what I have really said is, that all are not as perfect as they 

 might have been in relation to their conditions ; and this 

 is shown to be the case by so many native forms in many 

 quarters of the world having yielded their places to intrud- 

 ing foreigners. Nor can organic beings, even if they were 

 at any one time perfectly adapted to their conditions of life, 

 have remained so, when their conditions changed, unless 

 they themselves likewise changed ; and no one will dispute 

 that the physical conditions of each country, as well as the 

 number and kinds of its inhabitants, have undergone many 

 mutations. 



A critic has lately insisted, with some parade of mathe- 

 matical accuracy, that longevity is a great advantage to all 

 species, so that he who believes in natural selection " must 

 arrange his genealogical tree " in such a manner that all 

 the descendants have longer lives than their progenitors ! 

 Cannot our critics conceive that a biennial plant or one of 



