438 THE SUPPOSED TRANSMISSION OF MUTILATIONS. 



brought forward. But if nevertheless such a mysterious mechanism 

 existed between the parts of the body and the germ-cells, by means 

 of which each change in the former could be reproduced in a different 

 manner in the latter, the effects of this marvellous mechanism would 

 certainly be perceptible and could be subjected to experiment. 



But at present we have no evidence of the existence of any such 

 effects ; and the experiments described above disprove all the cases 

 of the supposed transmission of single mutilations. 



Of course, I do not maintain that such cases are to be always 

 explained by want of sufficient observation. In order to make 

 my position clear, I propose to discuss two further classes of 

 observations. First of all, there are very many cases of the ap- 

 parent transmission of mutilations in which it was not the mutila- 

 tion or its consequences which was transmitted, but the predis- 

 position of the part in question to become diseased. Richter l has 

 recently pointed out that arrests of development, so slight as to lie 

 externally invisible, frequently occur, and that such arrests exhibit 

 a tendency to lead to the visible degeneration of parts in which 

 they occur, as the result of slight injuries. Since therefore the 

 predisposition towards such arrest is transmitted by the germ 

 occasionally even in an increased degree the appearance of a trans- 

 mitted injury may arise. In this way Richter explains, for in- 

 stance, the frequently quoted case of the soldier who lost his left 

 eye by inflammation fifteen years before he was married, and who 

 had two sons with left eyes malformed (microphthalmic). Micro- 

 phthalmia is an arrest of development. The soldier did not lose 

 his eye simply because it was injured, but because it was predis- 

 posed to become diseased from the beginning and readily became 

 inflamed after a slight injury. He did not transmit to his sons 

 the injury or its results, but only microphthalmia, the predis- 

 position towards which was already innate in him. but which led in 

 his sons from the beginning, and without any obvious external 

 injury, to the malformation of the eye. I am inclined to explain 

 the case which Darwin in a similar manner adduced, during the 

 later years of his life, in favour of the transmission of acquired 

 characters, and which seemed to prove that a malformation of the 

 thumb produced by chilblains can be transmitted. The skin of a 



1 W. Richter, ' Zur Vererbung erworbener Charaktere,' Biolog. Centralblatt, Bd. 

 VIII. 1888, p. 289. 



