No. 1.] ORIGIN OF HUMAN MONSTERS. 253 
This remarkable specimen shows to what extent an embryo 
may grow after its regular development has been arrested. 
The specimen came to me attached to a solid body, as the 
photograph shows, and it appears to be an embryo about three 
weeks old. The free end of the embryo is bent upon itself 
and runs to a point where two intensely black spots may 
be seen. 
Fic. 252c.—Section through the embryo at its attachment to the chorion. 
x 20 times. 
The membrane or body behind the embryo is undoubtedly 
the amnion curled up, for it is covered with epithelium on the 
side towards the embryo side, which continues over its body. 
On the other side the mesoderm, which is thickened and 
hyaline, is free, there being no border cells nor villi. 
Fig. 252d.—Section through the embryo below its attachment to the chorion. 
The body immediately beneath the epidermis is a solid lentoid struc- 
ture. 
The skin is markedly thickened, the epidermis sometimes 
forming small papillae, or are sometimes buried, forming 
pear-like bodies similar to those of epithelial cancer. Within 
