The Columbia herald. [volume] (Columbia, Tenn.) 1850-1873, 1873-06-13
EXTRACT FROM LECTURE BY
AGASSTZ.
TRANSMISSION OF ANCESTRAL TRAIT


When we consider all these facts we
can hardly doubt that they are neces-
sary to the maintenance and reproduc-
sariIy pressed upon us, Which was first
in order, the parent that takes care of
the egg, or the egg out of which the
question discussed by philosophers of
antiquity, and with reference to which
we are not more advanced than they
were. They put it very simply, Which
was first In the beginning, the hen or
the egg? No eggs without hens. but
also no hens without eggs; and here
lies really the whole problem. We
have as yet no reason to assume that in
dividIals have ever grown or have ever
been formed under circumstances that
so essential to their maintenance and
production, unimportant to the original
d first introduction. The fxedness
and intricacy of the process by which
types are preserved will hardly allow us
to believe that they have ever differed
essentially from what they now are.
The problem of reproduction seems Ill
the abstract simple enough. There are
these eggs grow individuals like the
parent, and generation after generation
this phenomenon is repeated. But
when we would go back to the begin
ming we meet new difficulties and an
other set of considerations. How IS 1t
that such an egg holds IN itself the
power of producing eggs OF the same
kind, and transmitting that power gen
Grafton after generation? That is the
problem, and we must seek the answer
in the egg, not in the transformations OF
the adult animal, nor in the phenomena
of metamorphoses, nor in the superficial
variations brought about by special
training. Inseparable from the queS-
ton of reproduction is that of inherit
ance; and about that, though much has
been recorded, we do not yet know the
essential facts. What is the unquestion-
able, what everybody has witnessed, and
of the truth of which every one must
be convinced, is the fact that physical
and mental traits are transmitted from
one generation to the next. But be-
tween what is always maintained, and
never has been, and never will be
thrown off, and what may be dropped,
and what may be acquired, there lies
the debatable ground where we find
ourselves constantly baffled and at fault
Artificial. formulation will help us to
solve these perplexing problems by i'm
proving our information in that direc-
ton. When it is known by connected
and sustained observation what quail
tiles of one kind of animal may be
crossed with those of another kind, and
whether the progeny of the two are
capable of producing an offspring, we
shall have the means of testing how far
particularities are transmisslble and
may become permanent. One fact OF
this sort is already ascertained. Gen
orally the crossing of different species
produces terile offspring The cross
between horse and donkey, for instance,
produces mules; but here the process
comes to an end, for mules are generally
sterile, though a few cases are known
of fertile mules. There are, however,
two animals entirely distinct as to spec1-
fic charlottesville hare and the rabbit
of Europe, q do not speak of those of
the United States, respecting which
such observations have not yet been
made. J These animals have been crossed
and their offspring has proved to
the fertile, not with the original species,
the hare and the rabbit, but the cross
breeds themselves, the individuals de-
rived from the crossing of hare and
rabbit, have been fertile among them
selves. Thus new breed, which thus
far exists only@in domestic1ty, has been
produced and is known under the name
of leporide in the Paris market, where
it is as common now as the hare or raO-
bit. This new Lreed differs IN the color
of the flesh from both hare and rabbit,
the former being dark, the latter white,
while the leporide has an intermediate
condition of meat much esteemed for
It's favor and delicacy. Whether
new species could thus be produced in
the wild state as to point which shall
return in another part of my subject.
The question of hybridity, as we'll as
the artificial formulation, has its practi-
cal significance. Since it is important
in husbandary to produce breeds of
certain qualities and character, it would
be valuable to know what are the con-
ditions under which one or the other
parent influences the progeny and to
what extent.
THE DEVELOPMENT OF STOCK BREEDING.
We have seen that the offspring of
closely related animals may be like one
or the other parent, or may present
combination in various degrees of the
peculiarities of both parents. Upon
this fact and a knowledge of the condi-
tions under which it takes place, all the
operations of breeders are based.
Farmers inquire carefully into these
conditions, and from their observations
we have much to learn. Science has
not yet sifted the cases with precision,
and little is known of the means by
which certain qualities may be trans
mitted to offspring, and certain others
set aside. 1t is a current fact, however,
among breeders of horses and cattle,
that there are specimens especially va
lued in the community for the power of
making their progeny, as the express
sion is that is, for transmitting without
fail their qualities to their offspring,
while others have not that power.
These conditions lie, of course, at the
very foundation of the improvement IN
all our breeds, and they should be stu
died with the utmost care.
One interesting fact already appears,
as a result of these experiments on IN
ter-breeding conditions suddenly ARISE |
which seem to make reproduction I'M
possible, or which lead to malformatlon
or weakness, or lmpertect1on OF the |
progeny. There is tendency toward |
the limitation of extremes shown when |
ever we try to repeat too frequently or
draw too nearly characters intended TO
remain distinct. This has an impor-
tant lesson for the human family. To |
what degree may the combination be- |
tween closely allied individuals be car
ried with propriety and advantage
We know that by crossing representa-
tives of different species we obtain be
ings belonging neither to the one nor
TO the other, and not fertile among
themselves, and that if the process is
continued by crossing these hybrids
with the one or the other of species
which gave them birth, their peculiari-
ties are thrown off and return to
pure type is secured. Nature tends by
this process to maintain qualities as we
find them in pure races. individuals
of one and the same species are not,
however, necessarily closely related.
Dbax nov ba the progeny OF distant.