A REMARKABLE AXTICIPATIOX, ETC. 285 



too clearly and emphatically : "It seems to be the law of 

 the animal economy, that the organization of the offspring, 

 which as we have seen follows the type given by the 

 natural and original structure of the parent, is unaffected 

 by any change the latter may have undergone, and un- 

 influenced by any new state it may have acquired ". 



He then discusses the examples which are supposed to 

 support the opposite conclusion, first mentioning the statement 

 " that dogs and cats, the tails of which had been cut off, some- 

 times produce young ones which have a natural defect of the 

 same part. It is taken for granted that these appearances 

 are connected together in the relation of cause and effect, 

 and therefore afford a proof that acquired peculiarities are 

 hereditary." The author argues that cases of this kind are 

 accidental, and he points out that such defect of parts is apt to 

 occur in every species ; — in man as well as in animals. He 

 points to the vast experiment due to " our caprice " in muti- 

 lating the ears and tails of domestic animals, and to the 

 effects of surgical operations upon man. What remarkable 

 results would be witnessed if such changes were hereditary ! 



Professor Weismann was first led to the same conclusion 

 as Dr. Prichard by constructing a theory of heredity which 

 seemed to him to explain the facts and observations better 

 than any which had been previously proposed. But the 

 theory did not include any mechanism by which the trans- 

 mission of acquired characters could take place. Professor 

 Weismann, believing that his theory was in the main right, 

 began to inquire for the evidence on which the belief in 

 such transmission is based, and as soon as he commenced 

 his inquiries the evidence broke down in every direction. 



With Prichard it was otherwise, for the existing theories 

 seem to have been against him. Thus he argues that his 

 opponents "seem to have derived their opinion rather from 

 some conjectural theory of generation, than from any facts 

 which have appeared well established " ; and he goes on to 

 contend that we know so little "that we are not authorized 

 to reason from any hypothesis on this subject ". 



He next deals with the statement "that after mutilation 

 or other artificial change has been repeated through many 



