222 LUCK, OR CUNNING? 



areas of land and water, and independent of t£eir 

 physical condition. The naturalist must feel little 

 curiosity who is not led to inquire what this bond is. 



" This bond, on my theory, is simply inheritance, that 

 cause which alone," &c. (p. 35o)- 



This passage was altered in 1869 to "The bond is 

 simply inheritance." The paragraph concludes, " On 

 this principle of inheritance with modification, we can 

 understand how it is that sections of genera , . . are 

 confined to the same areas," &c. 



Again : — 



" He who rejects it rejects the vera causa of ordinary 

 generation," &c. (p. 352). 



We naturally ask, Why call natural selection the. 

 " main means of modification," if " ordinary genera- 

 tion " is a vera causa ? 



Again : — 



" In discussing this subject, we shall be enabled at 

 the same time to consider a point equally important 

 for us, namely, whether the several distinct species of 

 a genus, which on my theory haw all descended from a 

 common ancestor, can have migrated (undergoing modi- 

 fication during some part of their migration) from the 

 area inhabited by their progenitor" (p. 354). 



The words " on my theory " became " on our 

 theory" in 1869. 



Again : — 



" With those organic beings which never intercross 

 (if such exist) the species, on my theory, must have 

 descended from a succession of improved varieties,'' &c. 

 (p. 355)- 



