7% THE EVOLUTION OF MAH. 



amply sufficient to explain these phenomena. These causes 

 are : atmospheric influences ; water in its various forms — 

 such as snow and ice, fog and rain, the running stream 

 and the surging sea ; and finally, the volcanic phenomena 

 contributed by the hot liquid mass in the interior of the 

 earth. The most convincing proof was furnished by Lyell, 

 that these natural causes are quite sufficient to explain all the 

 phenomena of the structure and development of the crust 

 of the earth. The geological teaching of Cuvier as to the 

 revolutions and new creations was, therefore, soon totally 

 abandoned, but in Biology the doctrine prevailed unopposed 

 for thirty years longer. Zoologists and botanists, as far as 

 they at all permitted themselves to think on the origin of 

 organisms, adhered to Cuvier's false doctrine of repeated 

 new creations and re-formations of the earth. This is cer- 

 tainly one of the most curious examples of two closely 

 related sciences long pursuing utterly divergent courses. 

 One — Biology — remains far behind in the dualistic path, 

 and even denies the possibility of solving "questions of 

 creation " by the study of natural phenomena. The other — 

 Geology — moves far ahead in the monistic path, and solves 

 those very questions by the discovery of the actual causes. 



As an instance how utterly biologists refrained from in- 

 quiries into the origin of organisms, and the creation of the 

 animal and vegetable species, during this period from 1830 

 to 1859, I mention, from my own experience, the fact that 

 during all the whole course of my studies at the university, 

 I never heard a single word on these most important and 

 fundamental questions of biology. During this time, from 

 1852 to 1857, I had the good fortune to listen to the most 

 distinguished teachers in all branches of the science o/ 



