MltiCELLANEO US OBJECTIONS. \ 99 



CHAPTEK VII. 



MISCELLANEOUS OBJECTIONS TO THE THEORY OF NATURAL 



SELECTION. 



Longevity — Modifications not necessarily simultaneous — Modifica- 

 tions apparently of no direct service — Progressive develop- 

 ment — Characters of small functional importance, the most con- 

 stant — 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 struct- 

 ures — 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 dis- 

 guished 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 condi- 

 tions; and this is shown to be the case by so many native 

 forms in many quarters of the world having yielded tiieir 

 places to intruding foreigners. Nor can organic beings, 

 even if they were at any one time perfectly adajHed to 

 their conditions of life, have remained so, when their con- 

 ditions 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 inhab- 

 itants, 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 



