242 INTERNAL SECRETIONS 



we must assume that the ovarian change referred to, the 

 intensified production of lutein cells or of interstitial cells, 

 is the cause of the greater hormonic effect, or the cause of an 

 intensified production of sexual hormones. 



We have seen above that it is very likely that an hyper- 

 trophy of the interstitial cells takes place both in auto- and 

 homoiotransplantation. If this is true, one might expect to 

 find evidence of an intensified internal secretion also after 

 engrafting an ovary into a castrated female. In the first 

 edition of this book I pointed out that the microscopical 

 figures published by Marshall and Jolly (1907) suggest that 

 the uterus was more developed in the animal with auto- 

 transplantation than in the normal animal; the original 

 coloured figures 5 and 7 on Plate II. of their paper may be 

 referred to here ; but the black and white reproduction shows 

 this clearly enough (Fig. 49). I observed a rabbit on which in- 

 voluntarily an autotransplantation was made, and which gave 

 further support to my suggestion (1922 b). I castrated this 

 animal at an age of about two months. When killed sixteen 

 months later the uterus was found to be even more developed 

 than in one of the normal controls of the same litter. On 

 making a thorough examination of the abdominal cavity, 

 we found two pieces attached to the dorsal peritoneum and 

 resembling ovarian tissue although no Graafian follicles were 

 visible. The microscopical examination showed that the 

 pieces were really ovarian fragments which evidently under- 

 went an enormous hypertrophy and very profound alterations. 

 Although the weight of the tw^o pieces together was about 

 that of one normal ovary of the normal control, only a few 

 young ova were present in these fragments (Fig. 109 B) ; their 

 number may be estimated at a small percentage of the 

 normal number of ova (Fig. 109 A.) FoUicles at different stages 

 of ripeness were present, but hardly any distended Graafian 

 follicles; this indicates that there was an accelerated follicular 

 atresia in the ovarian fragments. The follicles were embedded 

 in the mass of interstitial cells in such a manner that they repre- 

 sented more or less the central part and the interstitial tissue the 

 cortical part of the fragment. The whole fragment was 

 covered by a thick capsule of connective tissue. The lack of 

 young ova in these ovarian fragments is to be explained by 

 the fact that most of them had entered upon folhcular 



