VIII.] SUPPOSED TRANSMISSION- Of MUTILATIONS. 459 



which cannot be admitted; but also and chiefly because a single 

 coincidence of an idea of the mother with an abnormahty in 

 the child does not form the proof of a causal connexion between 

 the two phenomena. 



I do not doubt that among the many thousands of present 

 and past students in German Universities, whose faces arc 

 covered with scars, there may be one with a son who exhibits 

 a birth-mark on the spot where the father possesses a scar. 

 All sorts of birth-marks occur, and why should they not some- 

 times have the appearance of a scar? Such a case, if it 

 occurred, would be acceptable to the adherents of the theory 

 of the transmission of acquired characters; it would in their 

 opinion completely upset the views of their opponents. 



But how could such a case, if it were really established, be 

 capable of proving the supposed form of hereditary transmis- 

 sion, any more than von Baer's case could prove the theory of 

 the efficacy of ' maternal impressions ' ? 



I am of opinion that the extraordinary rarity of such cases 

 strongly enforces the fact that we have to do with an accidental 

 and not a causal coincidence. If scars could be really trans- 

 mitted, we should expect very frequently to find birth-marks 

 which correspond to scars upon the face of the father, — viz. in 

 almost all cases in which the son had inherited the type of face 

 possessed by the father. If this were so we should have to be 

 seriously concerned about the beauty of the next generation in 

 Germany, as so many of our undergraduates follow the fashion 

 of decorating their faces with as many of these ' honourable 

 scars ' as possible. 



I have spoken of ' maternal impressions ' because I wished 

 to show that, until quite recently, distinguished and acute 

 scientific men have adhered to an idea, and believed that they 

 possessed the proof of an idea, which has now been completely 

 and for ever abandoned by science. But in addition to this, 

 there is a very close connexion between the theory of the 

 efficacy of maternal impressions and that of the transmission 

 of acquired characters, and sometimes they are even con- 

 founded together. 



Last year a popular scientific journal quoted the following 

 case as a proof of the transmission of mutilations. I do not. 

 however, wish to imply that the editor must be held responsible 



