140 PRIMITIVE ANIMALS 



the darker shades of decline and degeneration. The 

 genius of Darwin may have realized the part which 

 degeneration has played in evolution ; but the proofs 

 of its widespread influence have accumulated on the 

 shelves of the learned without penetrating the minds 

 of the populace, for whom the words evolution and 

 progress are often identical. The serious student of 

 evolution, relying upon the facts of comparative 

 anatomy and palaeontology, is forced to admit that 

 while the origin of the great advances in animal 

 organization are for the most part hidden from view, 

 the processes of extinction, degeneration and simpli- 

 fication are written large on all the great groups of 

 the animal kingdom as far back into geological time 

 as the record of them can be traced. With all this 

 evidence before us, how can we be confident that the 

 present race of man is only a step in a continuously 

 upward process of evolution? If it is true that 

 without a stringent measure of selection, every part 

 and function of the organism is apt to degenerate or 

 at any rate is incapable of progressive improvement, 

 the environment in which civilized man exists would 

 seem to involve of necessity a decline or stagnation of 

 many of his bodily operations, while the progress of 

 his mental and moral powers is fostered solely by 

 tradition, almost unaided by that process of selection 

 which we must believe to be an essential condition 

 of any permanent advance in organization. It is 



