iv VARIATIONS OF INHERITED INSANITY . 197 



" (a) Atavism. The bodily and mental organisation and 

 character can be transmitted from the first to the third 

 generation, without any necessity that the second and inter- 

 mediate one should exhibit the peculiarities of the first 

 thus the condition of the life and health of the grand- 

 parents are of interest for us. 



" (6) Only in rare cases is the actual disease transmitted 

 in procreation (congenital insanity, hereditary syphilis), as a 

 rule only the disposition thereto. Actual disease only occurs 

 when accessory injurious influences produce an effect based 

 upon that disposition. . . . 



" We must, therefore, consider also the state of health of the 

 relatives (uncles, cousins, aunts), and, since here also the law 

 of atavism holds good, the possible diseases of great-uncles 

 and great-aunts. 



" (c) Only exceptionally does the same disease develop in 

 ascendant as in descendant in consequence of the transmis- 

 sion of morbid dispositions. On the contrary, there exists 

 a remarkable variability in the forms of disease which may 

 almost claim the value of a law (the law of polymorphism or 

 transmutation). 



" The transmutations are innumerable. The most varied 

 neuroses and psychoses occur side by side in families with a 

 hereditary taint, and one after another throughout genera- 

 tions, and teach us that from a biological, etiological stand- 

 point they are only branches from one and the same 

 pathological stem. 



" The fact of the variability of the morbid conditions due to 

 heredity necessitates a careful examination of the question, 

 With what conditions and symptoms of morbid nervous 

 organisation hereditary transmission, direct or modified, is 

 connected ? 



" (a) In this respect there is no uncertainty about those 

 cases in which psychoses present themselves in both the 



