The IiiJieritance of Acquired Characters 59 



ory. Under the title of "Die Mneme," Semon has analyzed 

 and classified the different forms of inheritance of former ex- 

 periences of the individual which are assumed to become in 

 time the herditary capital of the race. Rignano has developed 

 the idea of the influence of the germ-cells on the soma, and 

 vice versa, from a different standpoint, viz. that the germ- 

 cells influence the soma during development and in turn are at 

 times influenced by the soma. These speculations are based on 

 the assumption that acquired characters are inherited. Since 

 Vi^e are concerned here only with the experimental evidence in 

 favor of or opposed to this assumption, it would carry us too 

 far to attempt to deal critically with these elaborations, that 

 assume at the starting point that such characters are inherited.^ 



Teiegony 



We may next examine the evidence that has been supposed 

 by certain writers, in the main "practical" breeders, to prove 

 that maternal impressions of various kinds can be transmitted 

 to the young in utero. The crudest examples are those in 

 which it is related how the pregnant mother, being impressed 

 by some unusual or revolting sight, has transmitted to her 

 infant a corresponding structural deformity. Somewhat less 

 credulous perhaps are those breeders and "fanciers" who are 

 firmly convinced that if a purely bred animal — the horse and 

 the dog are the stock examples — has first been paired with a 

 mongrel animal, the subsequent oft'spring to a purely bred 

 father will show evidences of the first birth, i.e. be impure as 

 to their breed. 



The credulity of men who have not been trained as to the 

 value of evidence is a matter of everyday observation, and it is 

 not going too far to say that most opinions or statements of the 

 "practical" breeder must be put to a rigorous scientific test 

 before they can be trusted. This has proven to be the case 

 with teiegony. 



^ For a criticism of Semon's argument, see Weismann's recent (1906) review. 



