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feditoricil. I 



The principal difference between the theories of the 

 origin of species advanced b}^ Darwin and DeVries appears 

 to depend entirely upon the length of a jump. According 

 to Darwin, present species have been derived from more 

 primitive ones by gradual variations from the type, those 

 best fitted to survive continuing to carry along the line of 

 development, the rest dying out. DeVrics, on the other 

 hand, maintains that new species spring full fledged from 

 old ones without these intergrading forms and that he has 

 actually brought this about in many cases. Unfortunate- 

 ly for the DeVriesian view, the new species produced are 

 unable to successfully compete with their neighbors, and 

 but for the intervention of man, die and leave no mark. It 

 seems conceivable to us that every plant is at times 

 throwing off these differing forms, and that the Darwinian 

 theor3^of the origin oi species takes this point into consid- 

 eration, but DeVries has shown us the important fact that 

 there is often greater difference between parent and off- 

 spring than Darwin supposed, and that, provided the 

 conditions are right, a new species may be produced in a 

 much shorter space of time than Darwin considered 

 possible. DeVries may be right in the main, but there are 

 some relations between plants and animals, the beginning 

 of which seem better explained by Darwin's view. In the 

 case ofmyrmecophilous plants it is much easier to suppose 

 that the plants and the ants that frequent them have been 

 evolved together, than that each by just the right muta- 

 tion at the right time have found themselves specially 

 adapted to each other. And if we consider the armed 

 stems of various plants to be principally for defense 

 against animals, it seems reasonable to infer that the 

 most prickl}^ or best protected have survived while the 

 weaklings have died out. Many plants are admirably 

 protected from grazing animals by thorns and spines. To 

 adopt the view of DeVries would be to assume that these 



