The San Francisco call. [volume] (San Francisco [Calif.]) 1895-1913, 1895-04-27
HOW HEREDITY OPERATES,
Lecture by DR.. HirsChfelder at
the Cooper Medical
College.
PHYSICAL, Mental and Moral Quail
ties Are Transmitted From
Parents.

! According 10 DR.. Joseph .. Hirschfelder
whose speciality as an instructor is medical
clinics. and at whose lectures young Dur.
rant was 4 frequent listener, the proverb is
true that The fathers have eaten sour
grapes and the children's teeth are set on
edge"
He lectured at the Cooper Medical
/ College last night on the subject OF
! "Heredity," to a good audience, and
! demonstrated that, though the survival OF
/ the fittest may be due to natural selection,
/ heredity has much to do with making us
what we are. He said, in substance:
II We watch the mode OF development of the
/ fHtus OF man we will find that during the
which it cannot be differentiated from the
! lower animals. In turn it represents fish,
a bird and quadruped. study OF
! the changes that occur teaches US that
| fetal lie passes through the forms that sci
ence has shown the race to have passed
through during geological periods in its
! progress from the simple-celled organisms TO
the highest development of the present.
The hereditary Transmission OF morbid con-
dItions is a well-known fact. 1t is observed in
every department OF medicine, but III no class
OF diseases is this more clearly seen than among
the nervous disorders.
The statistics of the insane ssylums show 10
what an enormous extent mental disorders are
hereditary. 1t has been found that in from one
!
! the hereditary faint Is manifest.
Not only so, but q special form of insanity
/ may be found 10 be handed down from genera
! uon TO generation. II is more usual, however,
! to find that the types of insanity are not con-
| slant in the family, and that different men,
| bers are somewhat dissimilarly diseased.
! But moral qualities and genius also are
| hereditary. Taking 1000 men of eminence
| composed OF Judges, statesmen, commanders
/ literary men, scientists, poets, musicians
| painters, diVineS, senior classes OF Cambridge
! OarSmpD and W-rpEtlpTS Col hoe
| found by studying their families, both in the
| ascending and descending lines, marked evil
/ dence OF the TACT that genius is hereditary.
one OF the most noted instances OF hereditary
! genius is found in the history of the Bach fam
/ lily, extending through eight generations and
among whom were found more than twenty
| eminent musicians and as many as ifty-seyen
sqmelenty distinguished to be mentioned in
! "tetIs' Dictionary OF Musicians"
But unfortunately the Daser nature is more
! apt to be handed down than the nobler at
! tributes. The study OF penology has demon
| stTated that the brains OF habitual criminals
! closely resemble those OF some of the lower
] animals, ana within certain limits the thief
! steals as the duckllng swims-by instinct-and
| the murderer resorts TO violence as naturally
| as a cat hunts mouse.
| In lntermarriages between Danes and East
Indlan women the children had the physique
! ana VlgOr or the European type, whereas moth
| ing OF the KIND occurs when the same women
| marry other Europeans. The intermarriage of
Sauc5ssians ana Mongolians results in half-
Whatever may be the sex Of the half breed
| ,LeEslLlaht observed that with the half-breed
chlIdTen OF Europeans and Hottentots the
horaI nature is always determined by the
| father, be he European or Hotteutot
| II We classify the various methods whereby
mercury operates We may group them under
| several forms. The first is direct Inheritance
/ Where we nave the transmission of both the
| offspring.
| In the ideal case the child would be an exact
| mean between the two parents hut such cases
never occur-we always find a preponderance
1 of one or the other
ia second great law OF heredity IL that NJ
ataYISm or reYersion, which operates when the
child resembles not so much the parents as q
grandparent or even more distant progenitor.
! IN the training OF animals this tendency to
reVeTslon acts as serious impediment. and in
plants 1t Is OF such frequent occurrence that
grating is universally resorted TO-
IT not 1ntrequently occurs that the offspriup
OF thoroughbred horses have the qualities of
some inferior ancestor that as the horse-fancier
says, they do not breed true"
Analogous observations have been made
both with plants and with animals An Fnglish
mare mare IN Iolo was bred with quagga and gave
Dlrtn 10 mule covered with stripes In lSt7
1918 and 1923 she bred with three different
ARABIAN stations and gave birth to three
brown colts with bands like the quaggs.
rms is the peculiar form of heredfty desig-
mated as influence. An instance may he of q
child OF O second marriage resembling the
former husband who had been long dead. and
with the mental resemblance even greater
than the physical
Our conclusion must be that the law of
hered1ty sets 4 limit to our mowers and cana
blllues, though we know that by properly di-
rected endeaVors we can progress in any direc-
ton we choose.
The gymnast and the student both find not
withstandtng the phenomenal success which
attended their first efforts they sooner or later
reach the limit heredity has fixed