Vol. 67.] ANNIVERSARY ADDRESS OF THE PRESIDENT. lxiii 



As the result of more than a century's work upon fossils we are 

 now well assured : — (1) That each Geological System is charac- 

 terised by a distinct fauna or flora ; (2) that each such fauna or 

 flora is, on the whole, an improvement on that which preceded it : 

 and (3) that the relation of a fauna or flora to its successor is of 

 an ancestral character. 



The numberless facts collected by geologists, and the inevitable 

 conclusions towards which they point, admit of their simplest 

 and most harmonious explanation on the theory of evolution, and r 

 indeed, they have furnished by far the strongest evidence in favour 

 of this doctrine. As yet they have not enabled us to discover the 

 machinery by which the evolution of life was brought about, but 

 we feel confident that on the chain of past life hangs the key both 

 to the conflict between existing views and to those future advances 

 in knowledge and opinion by which the mystery of evolution will 

 be ultimately solved. 



The year 1909— the jubilee of the « Origin of Species ' as well 

 as the centenary of its author — was marked by important memoirs 

 by Sir Archibald Geikie and Prof. Judd on the geological work 

 of Darwin himself; while last year Prof. Judd showed that the 

 broad and solid foundations on which Darwin built were laid for 

 him by Scrope and Lyell. 



(1) The Use of Geographical Parallels. 



While the Geologist has been able to infer from the facts at his 

 command, not only that an evolutionary chain of life has existed on 

 the earth, but that in the past, as in the present, biological conditions 

 of competition, food-supply, etc., have varied from time to time and 

 from place to place, he has, in demonstrating the immense varia- 

 tions in physical environment that have taken place in geological 

 time, made a third and at least equally important contribution to 

 evolution. He has proved that the climate, the relative position 

 of land and water, the height, the slope, and the very lithological 

 composition, of the land have been in a state of perpetual flux from, 

 the earliest periods to the present. 



This he has done by his acceptance and employment of the 

 fundamental principle of uniformitarianism, that the present is the 

 key to the past ; by his careful comparison of the phenomena of 

 the dead past with the results of the living processes of the present ; 

 by a study of the denudation and deposition, of earth-movement 

 and vulcanicity, of the birth, and growth, and death of land-forms. 



