No. 1.] ORIGIN OF HUMAN MONSTERS. 97 
PATHOLOGICAL EMBRYOS OF THE SECOND WEEK. 
The preceding pages have been devoted to the discussion 
of those pathological ova in which the embryos were nearly 
or entirely destroyed, leaving only the membranes. A large 
number of these specimens appeared to be normal ova when 
examined superficially, but careful examination showed that 
in many of them mucus, leucocytes and pus were present be- 
tween the villi. In many the chorion was thickened and more 
or less invaded by leucocytes and syncytium, while in others 
the cavity within had been obliterated completely to form 
typical fleshy moles. We have in them all stages of trans- 
formation between young normal ova and solid moles. 
The specimens in the preceding sections are easily divided 
into two groups: the first, in which the embryo and the 
amnion are destroyed, and the second, in which the embryo 
is destroyed but the amnion and more or less of the cord 
remains. In each of these groups there are intermediate 
stages which may be properly considered under this heading. 
In the first group these changes began in very early speci- 
mens, and in some of them the destruction of the embryo and 
amnion was not always complete. These might properly be 
considered with the embryos given in Table V, but I have 
found it more convenient not to do so and have included in 
this and subsequent tables only those embryos in which the 
form and structure could be made out with considerable cer- 
tainty. By doing this there is still a wide margin left for the 
imagination in linking the pathological specimens of a given 
week with normal embryos. After this has been done it is 
easier to correct errors than it is when the specimens in which 
the embryos have been destroyed are grouped with atrophic 
ones. My arrangement for the present is as follows: 
(1) Normal embryos. 
(2) Atrophic embryos. 
(3) Remnants of atrophic embryos. 
(4) Ova with amnion but without embryos. 
(5) Ova with neither amnion nor embryos. 
(6) Moles. 
