76 INTERNAL SECRETIONS OF THE OVARY 



reproduction, together with the occurrence of the changes 

 characteristic of the oestrous cycle, are dependent upon the 

 presence of the ovary. It is now necessary to consider the next 

 hnk in the chain of evidence that the ovary is an organ of inter- 

 nal secretion. So far as the effects of ovariectomy are concerned, 

 the ovarian control of the accessory organs might be a nervous 

 one, and it is necessary to show that the nervous connections of 

 the ovary may be entirely destroyed without adverse effects 

 upon the accessory organs, before this hypothesis can be dis- 

 missed. Such a demonstration is provided by the transplan- 

 tation of the ovaries to a different site in the body. 



Histology of the ovarian graft. The technique of grafting 

 ovaries has been described at length by many authors, including 

 Marshall and Jolly (452) and Lipschiitz (378). The usual site 

 of transplantation is the abdominal wall, the peritoneum, or the 

 kidney. Grafts readily ' take ' and survive if the ovary is from 

 the same individual (homoplastic graft), but survival is less 

 satisfactory when the ovary is from another individual even of 

 the same species (heteroplastic graft). Tissue from an animal 

 of a different species rarely survives for long. Many 

 workers have considered the histology of grafted tissue, 

 especially that of the ovarian graft into the male. Amongst 

 these may be mentioned Ribbert (534), Marshall and Jolly 

 (452, 453), Schultz (551), Steinach (591), Athias (50, 51), 

 Moore (462), Pettinari (515), Sand (542), Lipschiitz (378), and 

 Tamura (607). 



The first effect of transplantation of the ovary is that the 

 larger follicles tend to undergo atresia, and the corpora lutea 

 degenerate. If good vascular connections have been established, 

 the graft in the female undergoes growth, and the cyclic 

 changes characteristic of the normal ovary take place. If the 

 graft has a free surface, ovulation occurs, and true corpora lutea 

 are formed. Pregnancv from an ovarian graft has been recorded 

 by certain authors, including Morris (465) and Grigorieff (250). 

 Marshall and Jolly (453) state that homoplastic grafts in 

 the rat were found to be normal and to contain corpora lutea 

 after fourteen months, while heteroplastic grafts were normal 

 after six months. All workers agree, however, that follicular 

 atresia is more common in the grafted ovar}^ than in the normal; 



