THE CONVERGENCE OF THE EVIDENCES. 475 



the argument, it was remarked that the ensemble of vital 

 phenomena presented by the organic world as a whole, can- 

 not be properly dealt with apart from the ensemble of vital 

 phenomena presented by each organism, in the course of its 

 growth, development, and decay. The interpretation of either 

 implies interpretation of the other ; since the two are in 

 reality parts of one process. Hence, the validity of any 

 hypothesis respecting the one class of phenomena, may be 

 tested by its congruity with phenomena of the other class. 

 We are now about to pass to the more special phenomena of 

 development, as displayed in the structures and functions of 

 individual organisms. If the hypothesis that plants and 

 animals have been progressively evolved, be true, it must 

 furnish us with keys to these phenomena. We shall find that 

 it does this; and by doing it, gives numberless additional 

 vouchers for its truth. 



