REVIEW OF FOSSIL FISHES. 239 



the Laws of their Succession and Develop- 

 ment during all the Changes of the Terres- 

 trial Globe, accompanied by General Geolog- 

 ical Considerations ; finally, the Description 

 of about a thousand Species which no longer 

 exist, and whose Characters have been restored 

 from Remains contained in the Strata of the 

 Earth." 



The most novel results comprised in this 

 work were : first, the remodeling of the classi- 

 fication of the whole type of fishes, fossil and 

 living, and especially the separation of the 

 Ganoids from all other fishes, under the rank 

 of a distinct order; second, the recognition 

 of those combinations of reptilian and bird- 

 like characters in the earlier geological fishes, 

 which led the author to call them prophetic 

 types ; and third, his discovery of an anal- 

 ogy between the embryological phases of the 

 higher present fishes and the gradual intro- 

 duction of the whole type on earth, the series 

 in growth and the series in time revealing a 

 certain mutual correspondence. As these com- 

 prehensive laws have thrown light upon other 

 types of the animal kingdom beside that of 

 fishes, their discovery may be said to have 

 advanced general zoology as well as ichthy- 

 ology. 



