78 LECTURES ON EVOLUTION 



III 



hastened or retarded by variations in these con- 

 ditions ; or if evolution is simply a process of 

 accommodation to varying conditions ; the argu- 

 ment against the hypothesis of evolution based on. 

 the unchanged character of the Egyptian fauna is 

 worthless. For the monuments which are coeval 

 with the mummies testify as strongly to the 

 absence of change in the physical geography and 

 the general conditions of the land of Egypt, for 

 the time in question, as the mummies do to the 

 unvarying characters of its living population. 



The progress of research since Cuvier's time 

 has supplied far more striking examples of the 

 long duration of specific forms of life than 

 those which are furnished by the mummified 

 Ibises and Crocodiles of Egypt. A remarkable 

 case is to be found in your own country, in the 

 neighbourhood of the falls of Niagara. In the 

 immediate vicinity of the whirlpool, and again 

 upon Goat Island, in the superficial deposits which 

 cover the surface of the rocky subsoil in those 

 regions, there are found remains of animals in 

 perfect preservation, and among them, shells be- 

 longing to exactly the same species as those which 

 at present inhabit the still waters of Lake Erie. 

 It is evident, from the structure of the country, 

 that these animal remains were deposited in the 

 beds in which they occur at a time when the lake 

 extended over the region in which they are found. 

 This involves the conclusion that they lived and 



