No. 1.] ORIGIN OF HUMAN MONSTERS. 121 
sections show that there is an active growth of scar tissue at 
this point. In general, all the tissues are more or less dis- 
sociated, the cartilages and precartilages being most resistant. 
The walls 6f the heart and blood-vessels are not sharply 
defined and many blood cells spread from them into the sur- 
rounding tissues. The central canal of the spinal cord is dis- 
tended and the peripheral nerves are well infiltrated with 
round cells. The dissociation of the fore-brain and mid-brain 
is pretty complete, and the walls of the medulla are spreading 
out into its ventricle. In general, the head is reduced in size, 
The most marked secondary changes are seen in the 
mesenchyme of this specimen. At points there are fibrous 
thickenings in the skin, which frequently form papillomata, 
covered more or less with a single layer of epithelium. In 
front the face and chest have grown together, the point of 
union naturally closing the mouth, including the tip of the 
tongue in a mass of round cells. 
I picture the whole process as follows: In general, the de- 
struction of villi in the chorion is followed by fibrous atrophy 
of the umbilical cord and arrest of the heart beat. After the 
circulation has ceased the organs and tissues gradually dis- 
sociate and blood cells enter the tissues. Probably before 
the changed conditions had reached this extreme state the 
brain began to dissociate and became solid, and the face 
atrophied and united with the chest below. The changes in 
the rest of the embryo were not marked until the circulation 
ceased altogether. It is clear, however, that the brain dis- 
sociates before the rest of the embryo, for we constantly find 
in it more radical changes than in other portions of the 
embryo. 
Practically the same pathological changes described for 
specimen No. 311 are found in Nos. 375, 69, 174, 182 and 
325. No. 174 has horn-like processes and No. 182 has a 
straw-colored necrotic mass in front of the head. No. 325 
shows still more advanced changes, the necrosed liver is dis- 
integrating, this process having begun in 311. From all 
appearances this embryo has been dead for a long time, which 
is also indicated by its menstrual history. 
