PARTS CONCERNED IN REPRODUCTION. 251 



prepossession in favour of the existence of a real, though 

 hidden unity, in the essentials of this important function 

 throughout the whole range of organised heings. Feeling, 

 however, at the same time, that the very consciousness of 

 such a prepossession is some protection against its leading 

 into serious error, I now submit my conclusions, such as 

 they are, for the judgment of those whose position among 

 the cultivators of Natural Science entitles them to pronounce 

 upon them. 



