52 DARWINIANA. 



tation to the conditions of existence. ^ Tlie special 

 teleologists, sncli as Palej, occupy themselves with, 

 the latter only ; they refer particular facts to special 

 design, but leave ^an overwhehning array of the widest 

 facts inexjDlicable. The morphologists build on unity 

 of type, or that fundamental agreement in the struct- 

 ure of each great class of beings which is quite inde- 

 pendent of their habits or oonditions of life ; which 

 requires each individual '•' to go through a certain for- 

 mality," and to accept, at least for a time, certain or- 

 gans, whether they are of any use to him or not. 

 Philosophical minds form various conceptions for har- 

 monizing the two views theoretically. Mr. Darwin 

 harmonizes and explains them naturally. Adaptation 

 to the conditions of existence is the result of natural 

 selection ; unity of type, of unity of descent-. Accord- 

 ingly, as he puts his theory, he is bound to account for 

 the origination of new organs, and for their diversity 

 in each great type, for their specialization, and every 

 adaptation, of organ to function and of structure to 

 condition, through natural agencies. Whenever he 

 attempts this he reminds us of Lamarck, and shows 

 us how little light the science of a century devoted to 

 structural investigation has thrown upon the mystery 

 of organization. Here purely natural explanations 

 fail. The organs being given, natural selection may 

 account for some improvement ; if given of a variety 

 of sorts or grades, natural selection might determine 

 which should survive and where it should prevail. 

 On all this ground the only line for the theory to 



^ Owen adds a third, viz., vegetative repetition ; but this, in the 

 vegetable kingdom, is simply unity of type. 



