62 VARIATIONS, DUE TO REVERSION. 



Starting out, therefore, with these degenerate indi- 

 viduals of a species, Darwin essays to prove that their 

 development may proceed ad infinitum — and the evi- 

 dence, he adduces to countenance such an hypothesis, 

 is that, when placed under favorable conditions, those 

 individuals regain the characters which they once lost ! 

 The true, and only, induction from his facts, is, that 

 there are no positive characters which appear, which 

 are not due to the principle of reversion. The reader 

 should bear in mind, that the problem is, not how 

 species with all their characters, have been evolved ; 

 but, how have been evolved those slight increments of 

 development, which constitute the data of all the pre- 

 vailing theories of Evolution — those positive varia- 

 tions, or improvements, which arise under domestica- 

 tion, and (perhaps) under nature. The problem, How 

 species have been evolved, is the point to which Dar- 

 win addresses himself. But, in the solution of that 

 problem, he has availed himself of these variations, 

 and he professes, that these variations solve the ques- 

 tion. If, however, these variations be due to reversion 

 — if they be but the regain of what was once lost — 

 (which he furnishes such ample warrant for believing) 

 then is he mistaken in his belief, that they explain the 

 evolution of species. Therefore it is, that the prob- 

 lem of the evolution of species, gives place, in this 

 controversy, to the problem of the cause of variations ; 

 and, to the question whether there be a limit to the 

 improvements of which any species is shown to be 

 capable. If each species is capable of that amount, 

 only, of growth or development, of which it was pos- 



