CHAPTER IV 



THE INHERITANCE OF ACQUIRED CHARACTERS 



As has already been indicated, the question as to the 

 possibility of the inheritance of acquired characters 

 has been, and is, one of the most stubbornly fought 

 in the whole field of biology. This is in part due to 

 the great difficulty of the question itself, and in part 

 to its importance both in practical breeding and in its 

 bearing on our whole theory of heredity. 



It is safe to say that at least half the discussion 

 which has taken place on this subject has been a mere 

 matter of words. All sorts of misunderstandings have 

 arisen regarding the real question at issue ; and the 

 term " acquired character " itself has been too often 

 used to indicate just whatever a particular writer chose. 



We must then, in the first place, endeavour to under- 

 stand clearly what we mean by an acquired character ; 

 but, meantime, in case we should begin to think that 

 there is no real question under dispute, it may be well 

 to state one or two cases which bring out the real 

 difference of opinion. 



Suppose that a racehorse is put to stud before 

 having been trained for racing, and begets a number 

 of offspring. The next year he is trained and wins a 

 number of races. The following year he is again put 

 to stud, and mated with the same lot of mares as before. 

 Will the second group of offspring tend to be better 

 racehorses than the first ? In other words, will the 

 fact that the racing ability has been developed have 

 anything to do with the possibilities of speed in the 

 offspring ? One camp of biologists says " yes," the 

 other says " no." 



