No. 1.] ORIGIN OF HUMAN MONSTERS. 219 
unopened ovum was immediately placed in ninety-five per 
cent alcohol.” 
The ccelom is filled with granular magma, the chorion is 
very fibrous, and the villi are mostly wanting. The tissue of 
the mesoderm is very rich in nuclei, none of which appear 
to belong to leucocytes from the mother. Three kinds can 
easily be recognized—(1) those which normally belong to the 
mesoderm; (2) blood cells from the embryo; and (3) an ex- 
tensive invasion of the syncytial cells. This third group can 
be traced directly from large mounds of syncytium lying upon 
the chorion, from which they extend throughout the meso- 
derm, frequently entering the larger blood-vessels. Often 
large giant cells are seen, showing the usual characteristics 
of the syncytium after it has invaded the mesoderm of the 
chorion. ‘The villi are affected less than the main walls of the 
chorion. No cells from the syncytial layer of the chorion 
were found in any of the blood-vessels of either the embryo 
or the umbilical cord. ; 
The organs of this embryo are all normal in form and of 
the proper degree of development for an embryo of this size. 
The tissues are dissociated somewhat, the most marked being 
that of the brain. The veins of the body are all gorged with 
blood, with but little migration of blood cells into the sur- 
rounding tissues. 
. 
No. 189. 
Ovum, 28 x 25 x 15 mm.; embryo, 4 mm. 
Dr Oertel, Avicusta, Ga: 
The ovum, filled with granular and reticular magma and 
contains a deformed embryo, lying within a distended amnion, 
S mm. in diameter. 
The umbilical vesicle and amnion appear to be normal for 
an embryo of this size; the body, -however, is greatly de- 
formed, the central nervous system being open throughout its 
extent and encircles the dwarfed embryo like a broad hoop 
around a ball. A number of the motor roots of the spinal 
nerves are developed, more in the region of the tail than else- 
