58 MALL. [Vor. XIX. 
ine disease. Although this division does not correspond with 
the above three classes, in a general way it is suggested that 
women who are called normal abort with much hemorrhage, 
while the ones with uterine disease belong to the second and 
third classes mentioned above. Although these data indicate 
that pathological embryos are due to faulty implantation of 
the ovum, they by no means prove it. All of the ova in the 
third group of ten cases could certainly not have been destined 
to become pathological, for they all came from women who 
had given birth to healthy children. They could not attach 
themselves successfully to the diseased uterus, and, due to 
malnutrition or poisons which are thrown out from inflamed 
surfaces, the chorion became pathological and the embryos 
deformed. This point is fully proved, I believe, in the study 
of ova from tubal pregnancies. 
TWIN PREGNANCIES. 
Especially instructive and interesting are those cases in 
which two pathological ova were obtained from the same 
woman. Five such sets are found in my collection which I 
shall describe. The first set, Nos. 308 and 325, are from a 
woman who had born two children during the previous two 
years, and are especially valuable in this discussion. The 
first ovum (No. 308) appeared to me perfectly normal, and 
the embryo within it was not changed at all. However, the 
amnion was found filled with a jelly-like mass of granular 
magma, and this aroused my suspicion. Sections were 
therefore cut from the placenta at the attachment of the 
cord and a stringy mass rich in leucocytes was found between 
the villi. They were normal in form and possibly their 
mesoderm was fibrous in structure. Nine months later a sec- 
ond ovum was obtained from this woman, which was de- 
cidedly pathological. Both the chorion and the embryo were 
much changed, as the figures and description of the specimen 
will show. This case, which should be observed further, is 
to be explained by disease of the uterus, which began after 
the birth of the second child. This change had not gone far 
