The genetic origin of Dc-me-ntia Prriecox 87 



tions of normal testes the spermatozoa exhibited no visible evidence of 

 having acquired tails. 



Interstítial Tissiie. — There is an overgrowth of fibroblasts; the cells 

 of Leydig are diminished in size and numbers; tlie nuclei of the cells are 

 deficient in chromatin, smaller than normal, irregular in shape ¡nstead of 

 round, the cytoplasm is deficient in eosin staining substance, and the 

 appearance of the cells generally is that of immaturity (vide fig. 8, Band c). 



Sections stained by the Del Río-Hortega method show a great increa- 

 se of fibrous interstitial tissue, the amount in different regions of the or- 

 gan being proportional to the atrophy and disappearance of nuclear sub- 

 stance of the spermatogenic epithelium. 



Summary. 



This case is of interest from the following points of view: 



1) A family history of insanity on both paternal and maternal sides. 



2) A brother died of ballet wound of brain (accidental?); a pronoun- 

 ced regressive atrophy of the testis found similar in every respect to that 

 of the patient; a sister four times in Asylum — Recurrent manic-depres- 

 sive insanity with sexual delusions; a brother and sister normal; all the 

 family highly intelligent. 



3) The absence of evidence of intercurrent disease; post mortem — 

 death resulting from heart failure with cerebral congestión and oedema. 



4) Pronounced nuclear and cytological changes in the neurones 

 generally, but of the small cells of the cortex cerebri in particular; espe- 

 cially are the layers of stellate cells of Cajal affected. 



5) The micro-chemical and morphological changes in the nuclear 

 material of the cortex cerebri and of the testes can best be explained by 

 a germinal biochemical deficiency. 



The conclusions supporting the physiogenic origin 

 of dementia praecox. 



The fundamental clinical disorders of dementia praecox are a weaken- 

 ing of judgment, of attention, of mental activity and of creative ability, 

 the dulling of emotional interest and the loss of energy, lastly the loosen- 

 ing of the inner unity of the psychic life. Now if we assume that the 



