150 THOMPSON YATES AND JOHNSTON LABORATORIES REPORT 
which were crowded dense masses of deeply stained nuclei. In that part of the syn- 
cytium which was in contact with the maternal blood, a curious fringe-like appearance 
was seen, and, although 1 have noted this in several other cases, it was specially well 
marked here. The fringes, which are best seen with an oil immersion lens, resemble 
cilia very closely, and it is reasonable to suppose that they are provided to help on the 
stream of blood through large spaces, where of necessity the circulation must be very 
slow, and also, perhaps, to present a larger surface for the absorption of nutrient 
material for the growth of the vesicle. As the whole structure has no blood supply 
ot its own, it is dependent entirely on the maternal blood for its nourishment. 
Another striking feature of this case was the enormous number of leucocytes 
which were present in the blood, bathing the vesicles. In places, the number of white 
corpuscles exceeded even that of the red, and suggested, very forcibly, the idea that 
some infective process was going on. Many varieties of white cells were seen, lympho- 
cytes, large mononuclear and multinuclear leucocytes being specially numerous in 
those regions when the blood was in actual contact with a vesicle. 
It would appear from this that the vesicles themselves were the source of 
irritation, the blood reacting to- the stimulus and pouring out a dense leucocytic 
exudation, or it may be that the blood having been infected reacts again on the 
tissues of the mole, causing it to take on a malignant growth. 
Whether this be so or not, one is convinced, after the study of a large 
number of sections of vesicular mole, that a very real and intimate connexion exists 
between vesicular mole and the condition presently to be described, namelv, 
chorion carcinoma. Vesicular mole has been described by Frankel as a ' chorio- 
epithelioma benignum, and if the remains of a mole undergo malignant develop- 
ment there occurs a chorio-epithelioma malignum.' Other observers have described 
the condition as a cystic new formation, but the advocates ot this view are few. 
Virchow believed it to be a true hypertrophy of the villi with myxomatous 
degeneration ot the connective tissue of the stroma. 
Marchand, whose researches on this subject are of great value, lays 
emphasis on the proliferation of the syncytium and Langhans' cells, and regards 
the swelling of the vesicle as a dropsical condition produced mechanically and not a 
myxomatous degeneration. 
