ERRONEOUS DEDUCTION. 205 



these cases and the general principle of natural 

 selection that Nature has pronounced the sen- 

 tence of death upon highly specialized forms; 

 that they have passed out of the royal line of 

 descent for a special advantage; that if they 

 vary at all it can only be within the restricted 

 lines along which they have already gone so 

 far; and that the birthright belongs to forms 

 which have some general advantage, but are 

 not hampered by special adaptations. These 

 spread over the earth and from them branch 

 off the numerous closely related and variable 

 species that occupy all the environments of the 

 earth. Thus Drosera, with its power to catch 

 insects, is yet a plant like others, and has gone 

 forth with its advantage to possess the earth. 

 Vitis, with its climbing power, has scattered 

 its species by the hundred over the earth. It 

 is the modification that opens up to the species 

 a large area, which makes it possible for the 

 species to send out its kind into the whole 

 earth to be everywhere modified by local influ- 

 ences. 



The principle that has been discussed is now 

 one of the well understood corollaries of the 

 principle of natural selection. I do not know 

 who first called attention to it. It has prob- 

 ably occurred to many minds independently. 



