394 Maximilian Herzog. 



so "opsonized" them, that they became liable to be taken up by the 

 phagocytic action of other cells. We know that red blood cor- 

 puscles, in consequence of the action of certain bacterial toxins, are 

 so changed that this phagocytosis occurs. We want to mention in 

 this respect what occurs in typhoid fever when numerous red blood 

 corpuscles are taken up by the pulp endothelial cells of the spleen. 

 That the elements of the trophoblast of the human ovum under 

 absolutely normal conditions do exhibit towards the maternal 

 blood corpuscles truly phagocytic properties is certainly not proven. 

 Our own specimen, which we consider perfectly normal, shows abso- 

 lutely nothing which would justify such a conclusion. 



We see in the border zone, particularly around the equatorial 

 planes, cells which show already almost all of the characteristics 

 of the later decidual cells. These cells exhibit a large vesicular 

 nucleus, with rather scanty, finely granular chromatin and obtusely 

 fusiform or irregularly polygonal protoplasm. Between them are 

 found small mononuclear cells and polynuclear leucocytes. This is 

 the picture seen in places a little distant from the ovum. Towards 

 the very interior of the "Umlagerungszone," the outlines of almost 

 completely destroyed gland spaces with dropped-off degenerating 

 epithelia, red blood corpuscles and fibrin are seen abundantly. Here 

 also are seen these cells or cell remnants with pyknotic, irregular, 

 shrunken nuclei, and a very dense, deeply eosin-staining protoplasm. 

 The latter we consider as detached portions of the ectodermal tro- 

 phoblast. Protoplasmic masses containing several nuclei, which we 

 also take to come from the trophoblast, have already been men- 

 tioned. We have, however, not found larger masses of fused de- 

 generating cells, either of maternal or fetal origin, hence we have 

 no occasion in our case to make use of either one of the terms, 

 symplasma maternum or foetale. 



The Decidua. 

 The character of the decidua as it exists in our ovum is well illus- 

 trated in Figs. 24 and 26. In the "Umlagerungszone" and right 

 next to its periphery the degenerative processes and the hemorrhages 

 predominate. At some distance, however, we find a decidua well 



