RESULTS OF CASTRATION 33 



As in man changes in the hypophysis after castration have 

 T^een found in the rat, guinea pig, rabbit, horned cattle and 

 buffalo. An increased volume and weight and characteristic 

 histological changes have been recorded. (See especially 

 Schoenberg and Sakaguchi, 19 17). 



For the changes occurring after castration in the other 

 glands of internal secretion, such as the thyroid, the pineal, 

 the suprarenals, the thymus, BelVs book (1920, pp. 38-46) may 

 be referred to. According to Ocaranza (1921, 1922) a diminu- 

 tion of the number of the red corpuscles occurs after castra- 

 tion. Transplantation of testicle induces an increase in the 

 number of red corpuscles. But these changes are transitory. 



As already said, the changes in the skeleton as observed after 

 prepuberal castration, and characterized by Tandler and 

 Gross as a prolonged infantile stage, are probably caused 

 through the intermediation of the internally secreting glands. 

 The question of the mutual relations between the sexual 

 and other endocrine glands is of great importance in relation 

 to the physiology of growth. 



A great many observations have been made on the meta- 

 bolism of the castrated animal, but little definite knowledge 

 -exists on this subject. The accumulation of fat, however, 

 may be mentioned. In prepuberally and postpuberally 

 castrated male rabbits I found six to sixteen months later 

 enormous quantities of fat in the abdominal cavity such as I 

 never saw in normal males ; the quantity of the fat in the ab- 

 dominal cavity represented as much as 10 % of the body 

 weight, whereas in the control animal of the same litter less than 

 3 % of fat was found. The greater weight of the ''castrate" 

 seems to be due according to my weighing, especially, if not 

 "exclusively, to the accumulation of fat. Moore's papers 

 (1919, 1922) may be referred to, but further data are needed 

 on this point. 



2. The Psycho-sexual Behaviour of the Mammal. 



Besides the morphological changes a series of changes in 

 the psycho-sexual behaviour also has been recorded in the 

 castrated mammal.^ As far as I know the first systematic 



^ To simplify matters we will call all morphological and physiological charac- 

 ters alike physical or somatic. By "psycho-sexual behaviour" we mean 

 all the reactions brought about by the intermediation of the nervous system. 



