can, to throw ridicule on Christianity, while another will give you 

 a genealogical tree showing the ancestors of any species you like. 

 And many of us are familiar with the brilliant articles of Grant 

 Allen in the interests of the theory, in which he will commence 

 with an " if," or a " suppose," and then building on this supposi- 

 tion, triumphantly conclude with Q.E.D. 



What then is this Theory of Development ? I will make my 

 account as short as is consistent with lucidity. 



Everything on the earth, the earth itself, is in a state of constant 

 change ; rest and stability are nowhere to he found. Mountains 

 and seas alike disappear in time ; summer becomes winter, and 

 Avinter summer ; tlie climate of a hemisphere changes with the 

 lapse of ages. We dig up hero in England the fossil remains of 

 palms, cinnamons, figs, and Welliugtouias which once grew round 

 its old lakes ; we find stores of coal embedded in ice on the shores 

 of the Polar Sea ; the elephant and hippopotamus once fed on this 

 very spot, and the reindeer has occupied the south of sunny France. 



With all physical changes, of land and water and climate, the 

 animal and vegetable world juust change too, not only their 

 localities, but also in their structure and habits. Any species 

 unable to adapt itself to altered circumstances mvst disappear. It 

 is the riddle of the Sphynx, then, now, and ever — "Do this or 

 perish." When the climate of England was at one time sufficient 

 for the semi-tropical trees just mentioned, and at another was such 

 that every mountain top was swathed in ice, and every valley sent 

 out its glacier as the valleys of Switzerland do now, the species 

 suitable lor the former period could not exist in the latter. Con- 

 sequently they disappeared. And a fresh fauna and flora were 

 established in their stead. This explains the occurrence of the 

 remains of totally extinct animals. The same work is still in 

 progress. The Gair-fowl has disappeared from the earth within 

 the memory of living man, being convinced of the fruitlessness of 

 its struggle for existence. The earth is no longer fitted for it. 



Now the point in question is — How did the animals, new to the 

 earth, come into existence ? Was there a total destruction of one 

 ancient world of life, and a totally new and sudden creation of 

 another '? This was the belief of the early geologists. Or did new 

 forms (jraiJuallAj put in an appearance, being ijraduaUn created [i.e. 

 developed) out of the old ? coming in so slowly stepwise that no 

 one could ever say when the old form was succeeded by the new. 

 Ttiis latter view is what we are considerhig this evening ; it is this 

 idea which has been so industriously worked out by Wallace and 

 Darwin. 



If one thing is more certain to the geologist than another in his 

 studies it is this, — that since the appearance of the first form of 



