The New York herald., 1922-08-20

Fer most men the truth or untruth
Of Darwin's theory OF mans origin only
comes within the range OF their specI-
latiye thoughts. but for all who are in
vestigating the problems OF iAlng mat.
ter Darwinism enters into their daily
work. They depend on II, trust It as
Implicitly as a navigator does his Ad.
nniralty charts. This Is particularly the
case with professional students OF the
human body who, as Is the ease with
the writer, have, 10 discover ana to i'm.
part knowledge 10 generations OF med
teal students. The reader viii under.
stand this aspect 81 Dafwinissa Il
give a few illustrative instances Every
one is familiar with the faet that chill
dren are occasionally born wltA the
condition OF "harellp", In the complete
form cleft proceeds downward from
each fiost,il, dividing the upper lip into
three parts. The surgeon can mend the
deformlty by operation. but the aim of
the anatomist Is to discover why such
a rnalformatlon should occur ana. IL pos
sible. propose means to prevent It's be-
eurrehce. For help he turns to eifibry-
oiogy and finds that toward the end OF
the second month Of development the
upper lip is formed By the union or flu
sion or three stfuctuia al elements. II
union falls the condition Known as
''harelip" results. He mas then to am
swer the question. why should the ha-
man lip be originally cleft In three
parts? A suggestion Is given as to the
direction In which a search Should be
made by the simultaneous changes taxi
ing place In the neck OF the embryo +;
gill burrows are then disappearing. A
search among living fishes shows that
In one type. which has retained many
old and primitive characters the upper
lip, or what represents an upper lip, 10
divided into three parts by a cleft de-
scendlns to the mouth from each nasal
opening. ''Hareiip" represents the per-
slstenee OF an evolutionary change
which occurred long ago at very dis
tant stage of mans history. AT the
present time investigators are entering
the second part OF this problem ana are
seeking an answer to the question: Why.
should this stage occasionally persist?
Another puzzling occurrence was
solved In d similar manner. Some chill
dren are born with congenitai nalfor-
nation OF the heart, by far the common
est FORM being the Interpolation of a
small additional chamber on the right
side of the hetiH. A study OF the de-
velopment of this organ in the human
embryo has revealed the presence OF an
extra chamber, which In normal cir
cumstanees becomes gradually merged
into and absorbed by the right ventricle.
The extra chamber. which makes a tran
sient appearance In the human heart.
persists as an active structure in the
hearts Of sharks and rays. How are
we to explain the occurrence of this
fourth chamber In the heart OF the hu-
man embryo and It's occasional fetef-
ton In the child unless we accept the
validity of the Darwinian theory?
we may take another instance from
a discovery recently made by Professor
Dendy OF Kings College, London. He
found That certain remarkable fibers
which pass along the spinal cord of
fishes arose in connection with pecul-
lar plaque of cells situated in a passage
of the brain. He naturally wished to
know/w what had become of this plaque
and It's fbers during the evolution OF
higher vertebrates. He was able to dem
onstrate that even In the brain Of man