244 LOUIS AGASSIZ. 



theories. To him, development meant devel- 

 opment of plan as expressed in structure, not 

 the change of one structure into another. To 

 his apprehension the change was based upon 

 intellectual, not upon material causes. He 

 sums up his own conviction with reference to 

 this question as follows : l " Such facts pro- 

 claim aloud principles not yet discussed in 

 science, but which paleontological researches 

 place before the eyes of the observer with an 

 ever-increasing persistency. I speak of the 

 relations of the creation with the creator. 

 Phenomena closely allied in the order of their 

 succession, and yet without sufficient cause in 

 themselves for their appearance ; an infinite 

 diversity of species without any common ma- 

 terial bond, so grouping themselves as to pre- 

 sent the most admirable progressive develop- 

 ment to which our own species is linked, 

 are these not incontestable proofs of the ex- 

 istence of a superior intelligence whose power 

 alone could have established such an order 

 of things ? . . . 



"More than fifteen hundred species of fossil 

 fishes, which I have learned to know, tell me 

 that species do not pass insensibly one into 



1 Recherches sur les Poissons Fossiles, vol. i. chapter vi. pp. 

 171, 172. " Essay on the Classification of Fishes." 



