434 THE SUPPOSED TRANSMISSION OF MUTIL \TIONS. 



Hence the experiments on mice, when taken alone, do not con- 

 stitute a complete disproof of such a supposition : they would have 

 to be continued to infinity before we could maintain with certainty 

 that hereditary transmission cannot take place. But it must be 

 remembered that all the so-called proofs which have hitherto been 

 brought forward in favour of the transmission of mutilations assort 

 the transmission of a single mutilation which at once became 

 visible in the following generation. Furthermore the mutilation 

 was only inflicted upon one of the parents, not upon both, as in my 

 experiments with mice. Hence, contrasted with these experiments, 

 all such ' proofs ' collapse ; they must all depend upon error. 



It is for this reason important to consider those cases of 

 habitual mutilation which have been continually repeated for 

 numerous generations of men, and have not produced any hereditary 

 consequences. With regard to the habitually amputated tails of 

 cats and dogs I have already shown that there is only an ap- 

 parently hereditary effect. Furthermore, the mutilations of certain 

 parts of the human body, as practised by different nations from 

 times immemorial, have, in not a single instance, led to the mal- 

 formation or reduction of the parts in question. Such hereditary 

 effects have been produced neither by circumcision l , nor the re- 

 moval of the front teeth, nor the boring of holes in the lips or 

 nose, nor the extraordinary artificial crushing and crippling of the 

 feet of Chinese women. No child among any of the nations re- 

 ferred to possesses the slightest trace of these mutilations when born : 

 they have to be acquired anew in every generation. 



Similar cases can be proved to occur among animals. Professor 

 Kiihn of Halle pointed out to me that, for practical reasons, the 

 tail in a certain race of sheep has been cut off, during the last 

 hundred years, but that according to Nathusius, a sheep of this 

 race without a tail or with only a rudimentary tail has never lu-cn 

 born. This is all the more important because there are other 

 races of sheep in which the shortness of the tail is a distinguishing 

 peculiarity. Thus the nature of the sheep's tail does not imply 

 that it cannot disappear. 



1 It is certainly true that among nations which practise circumcision as a ritual, 

 children are sometimes born with a rudimentary prepuce, but this does not occur more 

 frequently than in other nations in which circumcision is not performed. Rather 

 extensive statistical investigations have led to this result. 



