46 UNIVERSAL EVOLUTION 



organisms are actually placed together in groups that 

 most other characters correspond also. The embryo- 

 logical characters are of more value in classification 

 than those of the adult form, because the embryo in 

 its development parallels, in a greater or less degree, 

 many of the embryological forms, through which the 

 ancestors of the embryo have passed. This is an impor- 

 tant point of proof of the truth of evolution, and the 

 close parallel, observable between classification and 

 descent with modification. "Community of descent is 

 the hidden bend which naturalists have been uncon- 

 sciously seeking, and not some unknown plan of crea- 

 tion, or the enunciation of general propositions, and the 

 mere putting together, and separating, objects more or 

 less alike." (Darwin). 



THE GREAT SIGNIFICANCE OF NATURAL CLASSIFICA- 

 TION. The importance of the broadening advances of 

 biological discoveries, from Linnaeus, who studied life 

 forms, from their most common and apparent outside 

 appearances, to Darwin and Wallace, who discovered the 

 methods and principles of evolution, cannot be over- 

 stated. Each step in advance tended to disclose the 

 homology and unity of all life forms. Cuvier, and the 

 comparative anatomists, made the first step from mere 

 outside form to structure. Then Bichat, the wonderful 

 genius, who died at 31, asserted that tissue made up the 

 bones, and flesh of all animals. Then Schwann and 

 Schleiden discovered that all tissue is formed by cells, 

 thus establishing the cell theory. Then Von Mohl, and 

 Max Schultz, showed that the cell is lined with a uni- 

 versal substance which Von Mohl named protoplasm, and 

 Schultz showed to be common to vegetable and animal 

 life. This protoplasm is the basis of all life, forming all 

 the parts of every life form, while Darwin showed that 



