APPENDIX I 237 



profound views of the causes of variation than any heretofore 

 promulgated. 



Again, since the germinal matter itself must be nourished 

 by the common blood of the animal, it is possible that it may 

 be influenced by any change by which this may be effected. 

 Popular speech recognises this by speaking of certain ten 

 dencies as being in the blood of certain races of animals. 

 , 2. Into the second field that of study of actual pheno- 

 jna Weismann has largely entered as a matter of experi- 

 t ent and observation, and his conclusion is that, as a rule, 

 fraracters impressed on the individual by accident or 

 external influences are not perpetuated. Those that are 

 congenital, being those that have originated in the germinal 

 matter of the parent, have alone the power to affect the ger 

 minal matter of the offspring. If, for example, an infant 

 from some cause, probably unknown to us, is born with 

 six fingers instead of five, this peculiarity, whether useful to 

 it or not, is likely to be perpetuated in some individuals at 

 least of the next generation. But if the child loses one of 

 its fingers by accident, its children are no more likely on 

 that account to be born with only four fingers ; or if it is 

 trained to use its fingers deftly in playing on an instrument 

 or working at any mechanical art, its children will not on 

 that account have more lissom fingers than others. This last 

 statement, however, should perhaps be taken with the limi 

 tation that if the use of the fingers is of such a character as 

 to act strongly on the mental or psychical nature of the adult, 

 or on the general system, it may in that case so affect its 

 terminal matter as to act on the offspring. This kind of 

 inheritance, as the Duke of Argyll has pointed out, is very 

 apparent in some domestic animals, as in dogs. 



It is curious that these conclusions of Weismann equally 

 affect Darwinism and Lamarckianism. They indeed bring 

 both these doctrines together, as mere modifications of one 



