TRANSMISSION OF CHARACTER 199 



directly and simultaneously in the germ and the 

 soma cells or in the soma cells first and in the germ 

 cells afterwards. 



"Another distinction, not less subtle and quite as 

 useless, for the explanation of evolution, is that made 

 by certain Weismannians, between the possible inher- 

 itance of a particular modification and the possible 

 inheritance of indirect results of that modification, or 

 of changes correlated with it. Thus for example, the 

 occupation of parents can exert an influence on their 

 children, but inasmuch as the children's structural 

 modifications are not similar to their parents' we will 

 not speak of the inheritance of acquired characters." 



The Weismannians also contend that an acquired 

 character must be transmitted in its totality from 

 parent to offspring. If the offspring presents a cer- 

 tain feature which is not absolutely identical with 

 that observed in the parent, although it may affect 

 the same tissue or the same organ, the Weismannians 

 class it with correlative characters and consider its 

 transmission as quite unimportant. 



This limits the debatable points more and more, al- 

 though in an artificial and arbitrary way. These re- 

 strictions do not throw any light on the subject but 

 they add almost insuperable difficulties to every exper- 

 iment which might prove conclusive. How can we 



s J. A. Thomson. Heredity, p. 190. (Thomsox admits to a certain 

 extent the heritability of these characters.) 



