PREMONITIONS OF BIOLOGICAL EVOLUTION 123 



simultaneously but separately created in Europe and 

 North America ; the teeth of the whale, which never 

 cut the gum, are the result of obedience to a certain 

 uniformity of fundamental structure. Explanations 

 like these removed no difficulties and suggested no 

 inquiries. In the hot debates which ensued the 

 Essay on Classification was rarely mentioned. 



I 2 



