THE HEREDITY OF RICHARD ROE. 131 
mathematics easier had his father devoted his life to 
exercise of that kind. But we are not sure that this is 
so. Wedo not know yet on what terms X and Y and 
X' and Y’ are passed over to Richard Roe, or whether 
they are passed on to him at all. In the view of Her- 
bert Spencer (“ Neo-Lamarckism”) X and Y are inher- 
ited, just as A and Bare. According to Weismann and 
his followers they are not subjects of heredity at all. 
I can not pretend to say what will be the final de- 
cision of science in regard to this vexed question, I 
venture to suggest that in Lamarck’s law and in the 
theories of many of his modern followers, too high value 
has been set, not on X and Y, but on 7 and On the 
other hand, if these fractions are really equal to zero, if 
acquired characters are absolutely of no value in hered- 
ity, some problems in biology we have thought easy. 
become tremendously complicated. We must rewrite a 
large portion of the literature of sociology. We must 
give a new diagnosis to Ibsen’s Ghosts. We must, in 
fact, do this in any event, for inheritance such as the 
Norwegian dramatist pictures it, belongs not to heredity 
at all, but is to be sought for among the phenomena of 
transmission and nutrition. They are matters of vege- 
tative development rather than of true heredity. Of 
the same nature is probably the recurrence of “spent 
passions and vanished sins”’ that certain peychologints 
ascribe to heredity. 
We may, I think, set aside the inheritance of ac- 
quired characters as not being a large factor in the 
changes of the higher animals. Prop- 
Nature of erly speaking, as Mr. Archdall Reid has 
pet ee well shown, nearly all the ‘characters of 
the adult are “acquired characters” as 
distinguished from innate characters. Heredity, for ex- 
