IN THE THEORY OF NATURAL SELECTION. 311 



known that' he produced artificial epilepsy in these animals by 

 dividing- certain parts of the central and also the peripheral nervous 

 system. The descendants of the animals which acquired epilepsy 

 sometimes inherited the disease of their parents. 



These experiments have been since repeated by Obersteiner l , 

 who has described them in a very exact and entirely unprejudiced 

 manner. The fact itself cannot be doubted : it is certain that some 

 of the descendants of animals in which epilepsy has been artificially 

 produced, have also themselves suffered from epilepsy in conse- 

 quence of the disease of their parents. This fact may be accepted 

 as proved, but in my opinion we have no right to conclude from it 

 that acquired characters can be transmitted. Epilepsy is not 

 a morphological character ; it is a disease. We could only speak 

 of the transmission of a morphological character, if a certain mor- 

 phological change which was the cause of epilepsy had been pro- 

 duced by the nervous lesion, and if a similar change had re-appeared 

 in the offspring, and had produced in them also the symptoms of 

 epilepsy. But that this really occurs is utterly unproved ; and is 

 even highly improbable. It has only been proved that many de- 

 scendants of artificially epileptic parents are small, weakly, and very 

 soon die ; and that others are paralysed in various parts of the 

 body, i. e. in one or both of the posterior or anterior extremities ; 

 while others again exhibit trophic paralysis of the cornea leading 

 to inflammation and the formation of pus. In addition to these 

 symptoms, the descendants in very rare cases exhibit upon the 

 application of certain stimuli to the skin, a tendency towards those 

 tonic and clonic convulsions together with loss of consciousness 

 which constitute the features of an epileptic attack. Out of thirty- 

 two descendants of epileptic parents only two exhibited such symp- 

 toms, both of them being very weakly, and dying at an early age. 



These experiments, although very interesting, do not enable us 

 to assert that a distinct morphological change is transmitted to 

 the offspring after having been artificially induced in the parents. 

 The injury caused by the division of a nerve is not transmitted, 

 and the part of the brain corresponding to that which was removed 

 from the parent is not absent from the offspring. The symptoms of 

 a disease are undoubtedly transmitted, but the cause of the disease 

 in the offspring is the real question which requires solution. The 



1 ' Oesterreichische medicinische Jahrbiicher.' Jahrgang, 1875, p. 179. 



