THE SUPPOSED TRANSMISSION OF MUTILATIONS. 439 



boy's thumbs had been badly broken by chilblains associated with 

 some skin disease. The thumbs became greatly swollen and re- 

 mained in this state for a long time ; when healed they were mal- 

 formed, and the nails always remained unusually narrow, short, 

 and thick. When this man married and had a family, two of his 

 children had similarly malformed thumbs, and even in the next 

 generation two daughters had malformed thumbs on both hands. 

 The case is too imperfectly known to admit of adequate criticism ; 

 but one may perhaps suggest that the skin of different individuals 

 varies immensely in its susceptibility to the effects of cold, and that 

 many children have chilblains readily and badly, while others are 

 not affected in this way. Sometimes members of the same family 

 vary in this respect, and the greater or less predisposition towards 

 the formation of chilblains corresponds with a different constitution 

 of the skin, in which some children follow the father and others 

 follow the mother. In Darwin's instance a high degree of sus- 

 ceptibility of the skin of the thumb was obviously innate in the 

 father, and this susceptibility was certainly transmitted, and led to 

 the similar malformation of the thumbs of the children, perhaps 

 very early and after the effect of a comparatively slight degree 

 of cold 1 . 



The last class of cases which I should wish to consider, refer to 

 observations in which the mutilation of the parent was certain, 

 and in which a malformation similar to the mutilation had ap- 

 peared in the child, but in which exact investigation shows that 

 the malformations in parent and child do not in reality correspond 

 to each other. 



In this class I include an instance which has only become known 

 during the present year (1888), and which has been observed as 



1 This case was not observed by Darwin himself, but was communicated to him by 

 J. P. Bishop of Perry, in North America (see 'Kosmos,' vol. ix. p. 458). Quite 

 apart from the fact that it is by no means certain whether the father did not already 

 possess an innate malformation of the thumb, exact data are wanting as to the 

 time during which the thumb was diseased, and as to the time when the malforma- 

 tion of the thumb was first observed in the children and the grandchildren ; whether 

 at birth or at a later period. For a thorough criticism it would also be necessary to 

 have figures of the thumbs. I should not have alluded to this case, because of its in- 

 complete history, if it had not appeared to me to illustrate the ideas mentioned 

 above. Of course I do not maintain that I have suggested the right explanation in 

 this particular case. It is possible that the father possessed an inherent malforma- 

 tion of the thumb which he had forgotten by the time that he came to have children 

 and grandchildren, and was struck by the abnormality of their thumbs. 



