RELATION OF VESICULAR MOLE TO CHORION CARCINOMA 159 
On closer examination, the protoplasmic bands are seen to correspond in every 
respect to the syncytium previously described. The ground substance is coarsely 
granular, stains well with eosin, and contains numerous vacuoles. On the surface, 
which is in contact with the blood, especially in those areas where the haemorrhage is 
most recent, the peculiar ciliated or fringed appearance is again noted, and adherent 
to these fringes a red corpuscle may here and there be seen. 
It will be remembered that this appearance is very characteristic ot the 
syncytium covering the vesicles in hydatidiform mole, and, in my opinion, is a point 
of great importance as demonstrating the intimate connexion between these two 
conditions. 
Lying in this protoplasmic substance, large numbers of nuclei are seen. The 
shape of these varies according to the position they occupy. Where the syncytium 
(as we shall now speak of it) is drawn out into long wavy strands, the nuclei are long, 
spindle, or rod-shaped, where a sharp curve is made, the nuclei are correspondingly 
curved or crescentic. In many places, however, the syncytium appears spread out 
into a flattened mass, with branching processes, or by cross section of a strand, oval 
and circular discs are seen, bearing a close resemblance to giant cells. Here the nuclei 
sometimes assume a large size, or there may be one or two very large oval nuclei, 
accompanied by several smaller ones. The oval or circular masses often contain a 
group of nuclei closely packed together, and, as they are always found lying free in a 
blood space, they resemble in every minute particular, the syncytial buds which are 
seen not only in sections ot hydatidiform mole, but also in normal villi, and even more 
markedly in the early stages of the development of the chorion. 
The nuclei of these giant cells are rich in chromatin, and, therefore, stain deeply 
with haematoxylin and with the aniline dyes, they shew numerous granules and fre- 
quently a well-defined nucleolus. 
Separated from the blood spaces by a thin layer of syncytium are seen the 
other variety of cells. These are so densely packed, that in very few places any 
definite cell can be made out. Where this is visible the cell appears oval or round, 
its protoplasm is not quite so granular as that of the syncytium, and does not stain 
as deeply. 
The nuclei are pale and transparent, and contain one or more nucleoli in 
almost all cases. When a number of granules are present, they are arranged at the 
periphery of the nucleus, leaving the centre clear and transparent. Nuclear vacuoles 
are also seen here and there. These cells are scarcely ever seen isolated, but are 
massed together in dense columns, and it is most interesting to observe that these 
cells do not come into actual contact with the blood, but are separated from it on all 
sides by a layer of syncytium (see Figs. 15 and 16, Plates XII and XI). 
As the tumour approaches the muscular wall, there are evidences that this is 
the growing edge. The haemorrhages are more recent, and the cells take on the 
