378 Maximilian Herzog. 



this is the case. The mass of the trophoblast in our case is certainly 

 many thonsand times that of the embryo. It does not stand to reason 

 to assume that nature in the phylogenetic development would pro- 

 vide, so to speak, at an enormous expense, a very large apparatus for 

 the nutrition of a very small embryo. It apj)ears more reasonable 

 to assume that the trophoblast with its great proliferative energy, 

 which we have likened to the growth of a malignant tumor, has more 

 exclusively the function to pro^'ide the means for the embryo to 

 safely implant itself at the very earliest date into the maternal 

 tissues. The reaction of the maternal tissues in contact with the 

 proliferating trophoblast must not be looked upon as due to mechan- 

 ical causes only, but to fermentative action of enzymes secreted by 

 the trophoblast cells and ditfused into the neighboring maternal 

 tissues." 



The above statement we still hold to be correct on the whole. 

 However, we agree with Bonnet^° that the syncytium presents feat- 

 ures, namely its property to stain very deeply with eosin, which 

 suggest the possibility that it takes up haemoglobin from the maternal 

 blood for the benefit of the nutrition of the embryo. 



The term syncytium in connection with placentation has been 

 used very promiscuously and has been inaccurately aj^plied to de- 

 generating confluent cell masses of maternal origin. According to 

 Bonnet, the term syncytium has been introduced into histology by 

 Haeckel, who designated by it a nuclei-containing jjlasma, formed 

 by the confluence of previously separate and distinct cells. Taken 

 in this sense, the term syncytium as aj^pied to the human tropho- 

 blast is probably a misnomer. It is very likely — though nothing 

 about this is known from actual observation — that the syncytium 

 of the human placenta is formed "ab origine," as an outer strip 

 or capsule of protoplasm which is provided with expelled nuclei 

 from the cells of the inner cellular trophoblast. In a publication 

 "On the Pathology of Tubal Pregnancy," quoted in a footnote above, 

 I have considered the syncytium of the human placenta as the homo- 



"Bonnet : Ueber Syncytium, Plasmodien und Symplasma in der Placenta 

 der Saugetbiere und des Menscben. Monatscbrift fur Geb. u. Gyn., 1903, 

 vol. 18, p. 1. 



