ake of
clearness: the mother receives a wound on the arm; when her child is
born it is found to have a scar of some sort at about the same place on
the corresponding arm. Few mothers would fail to see the result of a
maternal impression here. But how could this mark have been transmitted?
This is not a question of the transmission of acquired characters
through the germ-plasm, or anything of that sort, for the child was
already formed when the mother was injured. One is obliged, therefore,
to believe that the injury was in some way transmitted through the
placenta, the only connection between the mother and the unborn child;
and that it was then reproduced in some way in the child.

Here is a situation which, examined in the cold light of reason, puts a
heavy enough strain on the credulity. Such an influence can reach the
embryo only through the blood of the mother. Is it conceivable to any
rational human being, that a scar, or what not, on the mother's body can
be dissolved in her blood, pass through the placenta into the child's
circulation, and then gather itself together into a definite scar on the
infant's arm?

There is just as much reason to expect the child to grow to resemble the
cow on whose milk it is fed after birth, as to expect it to grow to
resemble its mother, because of prenatal influence, as the term is
customarily used, for once development has begun, the child draws
nothing more than nourishment from its mother.

Of course we are accustomed to the pious rejoinder that man must not
expect to understand all the mysteries of life; and to hear vague talk
about the wonder of wireless telegraphy. But wireless telegraphy is
something very definite and tangible--there is little mystery about it.
Waves of a given frequency are sent off, and caught by an instrument
attuned to the same frequency. How any rational person can support a
belief in maternal impressions by such an analogy, if he knows anything
about anatomy and physiology, passes comprehension.

Now we are far from declaring that a reason can be found for everything
that happens. Science does not refuse belief in an observed fact merely
because it is unexplainable. But let us examine this case of maternal
impressions a little further. What can be learned of the time element?

Immediately arises the significant fact that most of the marks,
deformities and other effects which are credited to prenatal influence
must on this hypothesis take place at