78 



INTERNAL SECRETION 



All the foregoing fact's show that the ovary, just like the 

 testis, has a far-reaching influence on the metabolism of the 

 body, this influence manifesting itself in helping to develop 

 and maintain the secondary sexual characters. Until recently 

 this influence has generally been supposed to be nervous. As 

 we shall see below, the evidence as to one or several kinds of 

 internal secretion is now tolerably conclusive. 



Considerable attention has been paid to the subject of 

 ovarian transplantation. Unfortunately there has been some 

 confusion in the terminology. In the present section the term 

 " autoplastic " will be used in cases where the organ is trans- 



Group I 



ill 



IV 



Normal 



FIG. 12. The effect of double ovariotomy on the growth of the uterus in 

 young rabbits. The first five are the uteri from rabbits who had both 

 ovaries removed on March 2, 1921, and were kept alive till June 7. 

 Number 6 is a normal control. Note the effect of ovariotomy on the 

 size of the uterus. No. 3 was a month older than the others. (Photo 

 by Sutherland Simpson, from a class experiment carried out by students 

 at Cornell University). 



planted into some part of the body of the same individual. A 

 " homoplastic " transplantation will refer to a graft made from 

 one individual to another belonging to the same species, while 

 " heteroplastic " will be the term applied to a graft from one 

 animal to a second belonging to a different species. 



In human beings ovarian transplantation has been carried out 

 on many occasions, with varying degrees of success. Morris 



