338 THE POPULAR SCIENCE MONTHLY. 



heredity, that the cure in the parent which has so characteristic 

 stages should have exactly the same stages in the young as to cir- 

 cumstances and time? 



I have said that I would only deal with this subject of heredity in 

 its physiological aspects, but I cannot refrain from recalling to the 

 attention of the reader that such facts in the human species need to 

 be studied by psychological physicians, because they occur in insane 

 patients, as is well known. Those alterations of the ears of which I 

 have spoken at first are frequently met with in the ears of demented 

 patients ; physicians call them baematoma. I have satisfied myself that 

 it is even more frequent than suspected in the inmates of asylums. 

 That state of stupor, or stupidity, and of insanity, in the Guinea-pig, 

 is of very frequent occurrence in the human epileptic. I could tell a 

 long story of similar phenomena observed in our own species. 



I believe that, if any conclusion can at present be drawn from those 

 facts, a physiologist or a physician will state that it is not a disease 

 which is inherited, which is transmitted, but the power to develop 

 such a disease. On the one hand, a physiologist is bound to ac- 

 cept that the disease was originally developed as a consequence of 

 an anatomical alteration of a certain organ or nerve-cell or fibre ; and 

 on the other he is bound to consider that the same disease or conse- 

 quence develops itself in a young one which has no such circumstances 

 of anatomical alteration of a certain organ or nerve-cell or fibre at 

 least detectable by any means of investigation at present employed. 



This question of heredity is one of the most vexed, and I shall not 

 say much more about it at present ; but as I have stated that I am 

 sure that there were no causes of eiTor in the facts themselves or the 

 deductions drawn from them, I take this opportvmity to say that 

 Mr. Galton has committed a grave error, in his very remarkable 

 paper on "Heredity" published not very long ago, in which he 

 stated that the Guinea-pigs which had epilepsy without alteration 

 induced in their nervous system may have acquired the disease by 

 imitation, just as, it is well known, is too frequently the case in the 

 human species. 



First, all the children or adults who happen to live with epileptic 

 patients and witness their paroxysms do not develop epilei^sy ; only a 

 very few do so. This fact would show, therefore, that those who do 

 develop epilepsy have some tendency ; but the argument of Mr. Galton 

 does not hold good with regard to the first two series of facts wliich I 

 have reported, and specially in the case of the Guinea-pigs which in- 

 herit epilepsy. How will he account, on the strength of his hypothesis, 

 for the fact that, out of a couple of hundreds of young which were 

 born from epileptic parents during the lapse of several winters in Dr. 

 Brown-Sequard's laboratory in Paris, and which I have very studi- 

 ously watched, only three became epileptic, although all lived to- 

 gether and all witnessed the fits of their parents, and only those three 



