INHERITANCE 



319 



individual parents may have gained ? This is an exceed- 

 ingly important question, the answer to which must have 

 something to do with determining our educational policy. 



In the long run all characters are acquired characters, if 

 evolution be conceded. The question is, Can the peculiar 

 conditions which cause new characters to develop in the 

 body so affect its germ cells that these will develop the same 

 characters in the next generation, even in absence of the con- 

 ditions that first called them forth ? When we remember 

 the early isolation of the germ cells, their lack of participa- 

 tion in the work of the body, and their remoteness from con- 

 tact with environment this seems unlikely. How, for 

 example, could the abuse of the eyes, causing partial blind- 

 ness in the adult, so affect the germ cells that have no eyes, 

 as to cause them to develop in the next generation, with 

 proper use, the same weakness? That new characters are 

 acquired by the individual body needs no proof; that they 

 are at the same time acquired by its germ cells is not proved, 

 although it has been widely believed. Mutilations of the 

 body we know are not inherited. The loss of an eye in one 

 generation does not prevent its perfect development in the 

 next.* The tails of sheep have been docked for centuries, 

 and yet lambs continue to develop tails in apparently 

 undiminished luxuriance. 



On the other hand, there are facts showing that the germ 

 cells (or, at least, the sex organs, collectively) do affect 

 the characters of the body of which they are an isolated 

 part. The effects of castration (removal of the spermaries) 

 of young animals are often very marked. The differences 

 between a bull and a steer, for example, are very apparent 

 in the horns and neck muscles, in voice and attitudes, in 

 disposition, in ability to put on fat quickly, and in other 



*"Wooden legs do not run in families, but wooden heads do." 



CONKLIN. 



