THEORY OF THE EARTH. 127 



sent day. Some slight differences are discover- 

 able between ibis and ibis, for example, just as we 

 now find differences in the descriptions of natural- 

 ists ; but I have removed all doubts on that sub- 

 ject, in a memoir on the Ibis of the ancient Egyp- 

 tians, in which I have clearly shown that this 

 bird is precisely the same in all respects at pre- 

 sent that it was in the days of the Pharaohs.* I am 

 aware that in these I only cite the monuments of 

 two or three thousand years back ; but this is the 

 most remote antiquity to which we can resort in 

 such a case. 



From all these well-established facts, there 

 does not seem to be the smallest foundation for 

 supposing, that the new genera which I have dis- 

 covered or established among extraneous fossils, 

 such as the palceotherium, anoplotherium, megalonyx^ 

 mastodon, pterodactylis, &c. have ever been the 

 sources of any of our present animals, which only dif- 

 fer so far as they are influenced by time or climate. 

 Even if it should prove true, which I am far from 

 believing to be the case, that the fossil elephants, 

 rhinoceroses, elks, and bears, do not diner far- 

 ther from the presently existing species of the 

 same genera, than the present races of dogs dif- 

 fer among themselves, this would by no means 



* In that dissertation, the ibis of the ancient Egyptians is shown to 

 be a species of numenius, or curlew, denominated by Cuvier nw- 

 menius ibis ; the same bird described in Bruce's Travels under the 

 name of abU'hannes.TrtsnsL 



