EFFEQTS OF USE INHERITED? 



to suppose that the particular condition of 

 parental parts transmits itself, or tends to 

 transmit itself, to the offspring. So unsatis- 

 factory is the argument derivable from inherited 

 mutilations that Mr. Spencer does not mention 

 them at all, and Darwin has to attribute them 

 to a special cause which is independent of any 

 general theory of use-inheritance. 1 



Darwin's most striking case and to my mind 

 the only case of any importance is that of Brown- 

 Sequard's epileptic guinea-pigs, which inherited the 

 mutilated condition of parents who had gnawed 

 off their own gangrenous toes when anaesthetic 

 through the sciatic nerve having been divided. 2 



1 A very able anatomist of my acquaintance denies the inheritance 

 of mutilations and injuries, although he strongly believes in the 

 inheritance of the effects of use and disuse. 



2 Variation of Animals and Plants under Domestication, i. 467- 

 469. Lost toes were only seen by Dr. Dupuy in three young out 

 of two hundred. Obersteiner found that most of the offspring of 

 his epileptic guinea-pigs were injuriously affected, being weakly, 

 small, paralysed in one or more limbs, and so forth. Only two 



