ORGANS OF INTERNAL SECRETION 355 



Liithje's castrated dogs, which did not exhibit any change 

 from their normal habits and movements, there was no diminu- 

 tion in the gaseous exchange as compared with control animals. 



Loewy and Richter,^ however, have arrived at different 

 conclusions, finding pronounced reduction in the respiratory 

 metaboHsm of castrated dogs of both sexes. Fui-thermore, 

 these investigators found that after feeding the female animals 

 upon ovarian substances there was a great increase in the 

 metabohsm, a castrated bitch showing an increase of from 

 30 to 50 per cent, above the normal values observed before the 

 operation. Testicular substance had no influence upon any 

 of the castrated animals, while normal animals did not react at 

 all either to ovarian or to testicular extracts. Loewy and 

 Richter suggest that the ovaries produce a specific substance 

 which promotes oxidation in the body. 



Zuntz ^ has investigated the gaseous metabohsm in four 

 castrated women, and found that it lay within the Hmits of 

 the normal. It is to be noted that neither of these women 

 showed any tendency to corpulence. These observations 

 support the view that when castrated animals show a reduction 

 in the respiratory exchange, this is an indirect effect resulting 

 from greater indolence of disposition. On this view also, the 

 tendency towards a deposition of fat on the part of many 

 castrated animals is to be attributed to the same cause. 



Dr. Cramer,^ working in conjunction with the author, has 

 lately investigated the respiratory metabohsm of a number 

 of rats whose ovaries had been removed some time previously, 

 and in these animals it was found that the gaseous exchange 

 lay within the hmits of the normal, thus confirming Zuntz's 

 experience with castrated women. It is possible, however, 

 that the results of castration were obscured by other factors. 

 In this investigation the apparatus employed by Haldane and 

 Priestley was used in preference to that of Zuntz. We did 

 not observe any marked tendenfcy to deposition of fat in the 

 castrated rats. 



' Loewy and Richter, " Sexual-Funktion und StofEweohsel ," Arch. f. 

 Phys., Supplement, 1899. 



2 Zuntz, " Gasweohsel bei Kastrierten Frauen," Verhandl. d. Oynak. 

 Gesell., Berlin, 1904. See also Deutsch. Zeitschr. f. Chir., vol. 65, 1908. 



' Cramer and Marshall. MS. unpublished. 



