OBSERVATIONS AND EXPERIMENTS 211 



ous cases offered as evidence, beginning with the most 

 doubtful ones. 



One of the simplest and easiest experiments con- 

 sists in performing a mutilation and observing its 

 hereditary effects. The results of such experiments 

 have supplied the opponents of the transmission the- 

 ory with their most powerful arguments, as mutila- 

 tions even though performed on several generations 

 are never inherited by the offspring. 



It is the custom in many countries to dock the tails 

 of cats and dogs, but these animals never bring forth 

 any tailless progeny. Weismann tried the same ex- 

 periment on several generations of rats without any 

 result. Every one knows that amputations, acciden- 

 tal injuries, like fractures or scars, are not trans- 

 mitted; neither are the mutilations customary among 

 certain races, such as circumcision among Hebrews 

 and Moslems, the deformation of the feet in Chinese 

 women, the piercing of nose or ears in savage tribes, 

 etc., which have not become hereditary in spite of hav- 

 ing been practised for numberless generations. 



It might not be possible to draw such definitive con- 

 clusions in the case of mutilations or lesions affecting 

 the whole organism, especially the nervous system, but 

 it can be said that, judging from the experiments 

 made thus far, mutilations are not hereditary. On 

 this score the Anti-Lamarckians triumph easily. The 

 theory of the transmissibility of acquired characters, 



