No. 1.] ORIGIN OF HUMAN MONSTERS. 269 
solid, fills the entire head and protrudes from an opening 
formed by the destruction of the forepart of the head. In 
front of this opening the atrophic upper jaw may be seen, 
containing nerves, and behind the epidermis has grown into 
a small ridge, encircling the opening. What has taken place 
in this embryo took place mechanically in No. 256 (see Plate 
III): The outlines of the organs are not sharp, but those of 
the precartilages are very definite. The blood-vessels are 
greatly dilated and filled with blood cells, which make them 
look like abscesses. They are especially well marked along 
the line from the umbilical cord to the heart. In their imme- 
diate neighborhood there is more or less infiltration with 
round cells. The smaller veins and arteries are still filled 
with blood. 
No. 278. 
Ovum, 6 x 4 mm. 
Dr. Stanton, Albany, N. Y. 
“This specimen was found accidentally in curettings from a 
woman supposed to have chronic endometritis following preg- 
nancy. There is nothing in the history by which the age of 
the specimen could be estimated.” Part of the specimen had 
been cut into sections before the specimen was sent with the 
statement that no embryo had been found, it having fallen out. 
I found that the half sent contained a ccelom, 3 x 2.5 mm. 
filled with magma, in which there was a cavity about 1.5 x I 
mm. Sections showed that the cavity was natural and not 
sharply defined, without anything to indicate that an embryo 
had been in it. On the contrary, it was found that the magma 
reticulé was filled with a loose net-work of mesoderm cells, 
which bound one side of the chorion with the other, as indi- 
cated in the diagram which is from a reconstruction. These 
cells are directly continuous with those of the mesoderm and 
resemble them in every particular. At one point there is a 
small group of epithelial cells, which may represent what was 
originally the embryo. 
Otherwise the chorion and its villi are normal in appear- 
ance, being encapsulated in decidua which has in it some 
