No. 1.] ORIGIN OF HUMAN MONSTERS. 87 
different. In so doing it makes more room for itself, the 
various structures from magma reticulé to decidua become 
intermixed, and if there is any further growth it is irregular, 
as is shown by numerous specimens. In specimens of this 
sort, that is those in which the amnion is destroyed in an 
early ovum, the diameter of the ccelom does not exceed 24 
mm. in any of my specimens, while if the amnion is retained 
and reaches the chorion, obliterating the ccelom, the amniotic 
cavity is then often over 75 mm. in diameter. In a measure 
this is repeating what takes place in normal development, for 
here the ccelom reaches its largest diameter (25 mm.) at the 
beginning of the fifth week. So in pathological ova, in which 
the amnion is absent, the ovum goes on developing, as in the 
normal, until the ccelom has reached its maximum size; 
beyond this it cannot continue to grow, for under normal 
conditions its further growth is due to the presence of blood- 
vessels in the chorion, which carry fluid to the embryo from 
which the liquor amnii is secreted. 
In case the ovum does not collapse, e. g., No. 358, the 
walls of the chorion become gradually thicker, the villi longer, 
and the diameter of the ccelom smaller. This is seen to be the 
case in regular order in specimens Nos. 55, 280, 70 and 223. 
No. 55, an ordinary fleshy mole, contains a sharply defined 
cavity, which proves to be the ccelom, for it is not lined by 
the amnion. From its lining membrane, the chorion, the 
villi rise and radiate through a mass of syncytium, decidua, 
blood, fibrin and pus. The bulk of the syncytium is necrotic 
and the mesoderm of the chorion is invaded in part by leu- 
cocytes. 
Another specimen (No. 185), as large as No. 55, is con- 
sidered here, for it was not the outside, but the inside, of the 
chorion that was filled with pus. No doubt the ovum was 
punctured by mechanical means and filled with pus, as was the 
early stage (No. 134) described above. In this the leucocytes 
invaded the chorion from the inside, but had not entered the 
villi. Some of the villi are atrophic and some are oedematous; 
the syncytium is normal. 
