No. 1.] ORIGIN OF HUMAN MONSTERS. 229 
which appear much as small villi inverted. At other points 
the epithelial covering of the amnion builds by itself a double 
layer of cells, which often gives rise to papilliform processes 
much like the syncytium on the outside. Sometimes this 
layer of epithelium is raised, forming a blister with a fibrin- 
like substance, possibly magma reticulé, throughout which 
are scattered transparent round cells with very small nuclei. 
The umbilical cord is quite fibrous, with large irregular 
openings scattered throughout it. These are filled with a 
mucoid substance in which a few nuclei are scattered. The 
blood-vessels are all obliterated with the exception of the point 
of the attachment of the cord to the embryo, where irregular 
vessels are filled with blood. 
The external form of the embryo is well preserved and is 
covered entirely with epidermis which is much thickened. The 
brain and spinal cord are swollen, the former being practically 
solid in the region of the fore-brain. The heart and large ves- 
sels are gorged with blood which extends from them into the 
surrounding tissues, obliterating them almost entirely. Within 
this mass of migrating cells can be seen the outlines of some 
of the organs of an embryo about four weeks old. The liver, 
stomach, and lungs are riddled, and but the faintest mark of 
an endoccelom can be seen. It appears as if all the blood of 
this specimen accumulated within the embryo, the cord and 
the chorion being free, the extensive epidermis preventing the 
migration of the blood cells into the amniotic cavity. 
No. 207. 
Ovum, 70 x 45 xX 45 mm.; twin embryos, 16 mm. long. 
From Professor Brodel, Baltimore. 
The specimen came to me unopened and hardened in a 
strong solution of formalin. Its exterior is smooth with smail 
villi at one of its poles. Within there are two embryos, both 
macerated, with atrophic heads. The larger embryo meas- 
ures C. R., 16 mm. The other is a little smaller, but as it is 
broken, an exact measurement could not be made. The cords 
of both embryos are atrophic. 
