No. 1.] ORIGIN OF HUMAN MONSTERS. II 
and have gladly exchanged the hybridity theory (cohabita- 
tion with lower animals) for the more innocent one of 
maternal impressions. The last notion is of great antiquity, 
is of world-wide distribution and is intimately related to 
witchcraft. It is gratifying to note that these superstitions, 
based upon coincidences, have been raised from medicine by 
the study of scientific anatomy, and the more recent work by 
J. F. Meckel in this direction can be ranked with that of 
Morgagni and Virchow. Morgagni gave the first blow to 
humoral pathology by giving medicine an anatomical basis, 
Meckel cast out devils, witches and mother’s marks by placing 
teratology on an embryological basis, and Virchow won the 
third great victory for anatomy, probably the greatest con- 
tribution ever made to medicine, by giving it an histological 
basis. It would be inappropriate to enter any further into a 
discussion of teratogenesis in this publication, for in general 
the superstitious notions are abandoned by scientific physi- 
cians, although they may still be entertained by a few prac- 
titioners of some eminence. It is humiliating to state that 
these practitioners seem to reside exclusively in America, 
but we have every reason to hope that when scientific medical 
education becomes general with us they will also disappear. 
Most of the great men who have contributed to the prog- 
ress of medicine, from Hippocrates and Aristotle to the 
modern scientists, tried to ascribe the production of mon- 
sters to natural and not to supernatural processes. From the 
first the explanations were as satisfactory as they are to-day, 
for even now we barely do better than Aristotle did. How- 
ever, the spread of the scientific spirit beginning with the 
study and practice of anatomy by all medical students has 
driven medical superstitions pretty well out of the medical 
profession. In this respect we differ from the ancients. The 
first scientific explanations were of a crude mechanical nature, 
like those due to excessive lacing, malformations of the uterus 
or a twin fcetus, which might injure the embryo. This notion: 
was superseded in part by the theory of Morgagni, who 
maintained that monsters were due to fcetal disease. This 
