392 THE PHYSIOLOGY OF REPRODUCTION 



luteum in relation to the toxemias of pregnancy. By alcoholic 

 extraction from the fresh gland obtained from the ovaries of sows 

 and in some cases from women, they have prepared and isolated 

 a chemical substance which, when injected into animals, produces 

 necrosis and other changes similar to the toxaemias. Extracts of 

 placenta and of hydatiform mole, on the other hand, were found to 

 be non-toxic. The authors believe that the toxaemias which so 

 often occur in pregnancy are due to hyperactivity of the corpus 

 luteum, and they suggest further that it is the secretion from this 

 organ which reacts on the thyroid and stimulates it to growth and 

 hyperactivity. The excess of cholesterol during pregnancy is 

 regarded also as an attempt to neutralise the toxic effect of the 

 corpus luteum. The active principle was protein free, but it appeared 

 to be associated with a lipoid. Cholesterol, choline, histamine, and 

 tyramine were absent. " The highly refractile solution was found 

 to undergo destruction with the serum of a pregnant woman." The 

 test was likewise positive during the early stages of menstruation, 

 but otherwise with non-pregnant women it was negative, as it was 

 also with males. The changes were observed by means of the 

 refractometer. 



The influence of castration upon the blood has formed the subject 

 of a research by Breuer and Seiler, 1 who employed bitches whose 

 ovaries were removed shortly after puberty. They record marked 

 diminution in the haemoglobin and the red cells. 2 



In concluding this brief summary of the recorded results of 

 castration, and the influence of the generative organs upon the 

 metabolism, the necessity for further investigation must be em- 

 phasised, since it is hardly possible that the totality of the effects 

 produced is of as slight a nature as the accepted evidence at present 

 seems to indicate. 3 



1 Breuer and Seiler, "Einfluss der Kastration auf den Blutbefund weiblicher 

 Tiere," Experim. Archiv, vol. 1., 1903. 



- It has also been stated that castration may improve the quality of the 

 milk (Oceanu and Babes, " Les Effets Physiologiques de POvariotomie chez la 

 Chevre," C. R. de VAcad. des Sciences, vol. cxl., 1905). For some account of 

 the effects of disease in the ovaries and other reproductive organs upon the 

 rest of the body, see Wilson, " The Reciprocal Relations between the Affections 

 of the Uterus and its Appendages upon the Rest of the Body " (Lancet, Part II., 

 November 1906). further references are given in this paper. 



3 For a full bibliography see Barker, Endocrinology and Metabolism, New 

 York and London, 1922. For further experimental wo'rk on sexual characters 

 see Zawadowsky, Das (Jeschleclit und die Entwickehing das geschlechtmerkmale, 

 Moscow, 1922. (The work is written in Russian.) 



It has been found that ovariotomy performed in young Herdwick lambs 

 does not result in horn growth, though in one animal small scurs were formed ; 

 such scurs are said, however, sometimes to occur normally in Herdwick ewes 

 (Marshall, Proc. Roy. Soc., B., vol. Ixxxv., 1912 ; ef. p. 323 above). 



