SECRETORY FUNCTIONS IN HUMAN PLACENTA 489 



arguments for internal secretion in the placenta is very feeble 

 indeed, and much more is still to be done to accomplish a 

 consummate investigation of this subject. It should none the 

 less be added that Fraenkel ('14) was one of those who were 

 strongly opposed to the various theories given above, and he 

 denied the effects, which, it was believed, the placental func- 

 tions have upon the mammary glands, on the ground that ex- 

 actly the same phenomenon as takes place in the suckling of 

 mammals was observed in the suckling of Monotremata and 

 Marsupialia, neither of which has the placental formation. In 

 addition to that, Fraenkel, going so far as to discuss the changes 

 which the internal secretory glands and other organs have to 

 undergo in consequence of the placental extract as was witnessed 

 in the experimentations of the afore-mentioned authors, concluded 

 that such changes were attributable to several ingredients, his 

 so-called 'Gift,' contained in the extract. According to 

 Fraenkel, who contradicted the theory which generally is in 

 favor of the existence of internal secretion in the placenta, the 

 internal secretory glands first respond to this 'Gift,' and, as a 

 result, the other physical changes follow. In short, it may be 

 said with regard to the existence of internal secretion in the 

 placenta that, in spite of the numerous researches made along 

 the lines of experimentation, biological chemistry, and histology, 

 as I have mentioned above, the views expressed are so varied 

 that no conclusion has been reached, and, therefore, regarding 

 the real situation of this subject, it is at present not yet an estab- 

 lished theory. 



Many authors have given their attention to the existence of 

 an internal secretory function in the decidua, and have tried to 

 demonstrate it. Starling ('06), Sfameni, Gentili ('13 and '14), 

 Schottlander (14), Aschheim ('15), GentiU and Binaghi ('17) 

 being among the number. Starling conducted experiments on 

 the rabbit to find the effects which the juice extracted from 

 the mucous membrane of the uterus while in pregnancy exerts 

 upon the mammary glands, and the result was of a negative 

 nature. Sfameni . for many years past had held that in the 

 decidual cells there should be existent an internal secretory 



