technical language in which the theory is stated by its 
author. 
Before leaving the theory of Dr. Weismann, it may be 
well to indicate a certain ambiguity in the use of the word 
“acquired.” It is generally used to indicate variations 
acquired by the body cells of an organism ; and unless 
I am mistaken it is tacitly assumed that no acquired 
modification whatever can be inherited, and that therefore 
the transmutation of species in nature is due to the 
Natural Selection of variations necessarily associated with 
reproduction. But surely if external conditions can 
modify the sexual elements, these modifications have been 
acquired by the sexual elements; and, as we have seen, the 
necessity for Natural Selection at once disappears, and 
something very like a Lamarckian principle is at once 
established.