No. 1.] ORIGIN OF HUMAN MONSTERS. 5 
attached to the chorion through newly-formed bands of tissue, 
and such bands, whether present or not, are held responsible 
‘for all terata. This coincidence, as I term it, cannot be of 
frequent occurrence, for usually there is present an hydram- 
nios. Nor can even the “coincidence” occur in anamniotic 
animals. Furthermore, no amniotic bands were ever found in 
any of the 169 specimens which I have studied. 
In place of these theories it is my purpose to demonstrate 
that all monsters are produced by external influences upon 
normal ova which affect the nutrition of the embryos due to 
faulty implantation of the ovum. That the power to become 
a monster is present in every ovum is fully demonstrated by 
experiments upon a variety of vertebrates as well as by all 
of my pathological ova, especially those obtained from tubal 
pregnancies. 
The changes found repeatedly in the chorion are no doubt 
primary; they are usually of an hemorrhagic nature, often 
indicating inflammatory changes in the uterus. I shall only 
hint at the cause for the changes in the uterus, which may 
interfere with the formation of the decidua, and recommend 
this field as a very fertile one for gynecologists and obstet- 
ricians to investigate. At any rate, the change interferes much 
with the attachment of the ovum, and this condition and what 
results from it I have termed faulty implantation. 
It has been impossible, in fact it is not desirable, to discuss 
extensively the immense amount of excellent literature upon 
teratology. The whole makes one of the best chapters in 
medical literature to which the greatest minds of medicine 
have contributed their best efforts. One cannot go through 
these writings, many of which are comprehensive, without 
laying them aside with profound respect. In this study I 
have used many of them freely, but make, however, very few 
references.* I have also avoided technical terms as much as 
*J. F. Meckel, Handbuch d. pathol. Anatomie, Leipzig, 1812. 
Forster, Die Missbildungen des Menschen, Jena, 186s. 
Bischoff, Wagner’s Handworterbuch, 1842. 
Ahlfeld, Die Missbildungen des Menschen, Leipzig, 1880-1882. Part 
