Characters as Adaptive and Specific. 199 



stability in specific characters, as are the unknown 

 causes of stabiHty in many varietal characters ^. 



* Should it be objected that useless characters, according to my own 

 view of the Cessation of Selection, ought to disappear, and therefore 

 cannot be constant, the answer is evident For, by hypothesis, it is only 

 those useless characters which were at one time useful that disappear 

 under this principle. Selection cannot cease unless it was previously present 

 — i.e. save in cases where the now useless character was originally due 

 to selection. Hence, in all cases where it was due to any other cause, the 

 useless character will persist at least as long as its originating cause 

 continues to operate. And even after the latter (whatever it may be) 

 has ceased to operate, the useless character will but slowly degenerate, 

 until the eventual failure of heredity causes it to disappear in toto — long 

 before which time it may very well have become a generic, or some higher, 

 character. 



