ORGANIC EVOLUTION 59 



themselves under it. No more striking illustration of this 

 can be found, than in the contrasted fates of Cuvier's 

 theory and that of Darwin. Even before Cuvier's death, 

 his views had been undermined, and the progress of dis- 

 covery soon laid them in irreparable ruin; while the 

 activity of half a century in many different lines of 

 inquiry, has established the theory of evolution upon 

 a foundation of ever growing solidity. It is Darwin's 

 imperishable glory that he prescribed the lines along 

 which all the biological sciences were to advance, to 

 conquests not dreamed of, when he wrote." (W. B. 

 Scott). (1909). "If the doctrine of evolution had not 

 existed, paleontologists must have invented it, so in- 

 evitably is it forced upon the mind, by the study of the 

 remains of the Tertiary mammalia which have been 

 brought to light since 1859." (Huxley). In 1909, fifty 

 years from the publication of the "Origin of Species," 

 the evidence must have been very much more complete. 

 ADAPTIVE VARIATION. It is more than probable that 

 since organic life first appeared upon the earth there 

 have been many changes, in the contour of the globe, 

 and consequent changes of. climate. These have pro- 

 foundly affected organisms. Those living on the border 

 of the change, where no barriers interposed, were, 

 many of them, enabled to migrate to more favor- 

 able regions. But the great majority of the flora and 

 fauna would give way to changed conditions, and die 

 out. Organisms better adapted would eventually 

 come. A few of the more vigorous individuals, of the 

 old form, would survive, and gradually form new 

 habits, compatible -with the changed features. There 

 is not a perfect adaptation of all individuals in any 

 region, for changes minute and gradual, are taking 

 place everywhere. Paleontology shows this. The 



