212 THE CULTIVATOR. July 
«CTswji ) piigBaBaBSK«EgBBgig33SgaBgffi3iBBg3B5BB8!gSSK&EOgaiea^ 
the European Grain-worm.) It is true, their assist¬ 
ance does not arrive before the wheat is injured for 
flour, but they might aid in diminishing the enemies 7 
ranks for the next season. 
I hope your readers will do me the justice to admit 
that, if I have made this article twice as long and tire¬ 
some as it should be, I have at least duly interlarded it 
with (t possibly,” e{ perhaps,” “as nearly as I can as¬ 
certain,” and the like. This I do, partly, in order that, 
should Dr. Harris, or any other close investigator, de¬ 
tect me in error, I may be able to secure an honorable 
retreat, without danger of losing my character, as an 
accurate experimenter, or of being totally excluded 
from your columns. 
But seriously, when we consider how difficult it 
already is to separate truth from error, and how im¬ 
possible for each individual to determine, by personal 
investigation or experiment, the truth or falsehood of 
each asserted fact, it seems highly important (at least if 
we desire to advance knowledge in the world,) that 
statements made to the public should never be given as 
decided facts, unless warranted by repeated experiments. 
Even then we shall have errors enough; without this 
precaution, we must expect to have “ confusion worse 
confounded.” Richard Owen. 
New-Harmony, May 4, 1846. 
P. S. If you desire it, I can still send you drawings 
of the insect, in its various stages; exhibiting the moth 
of its natural size, and showing the appearance of the 
head and ovipositor, when magnified. 
May 10. This morning, although the thermometer 
is at 65 degrees, I found two moths, contrary to my 
expectation, ready to hatch out of corn; one of them 
had its antenna and part of its head out of the orifice, 
apparently reconnoitering the prospect. I extricated 
them both, by splitting the grains of corn, and found 
one of them encumbered with the pupa case; the other, 
on the contraiy, rather to my surprise, was enveloped 
in a white, web-like casing, which, except in this in¬ 
stance, had always appeared to me to be used only as a 
pai'tition in the channel, not as an envelope for the 
chrysalis. 
[We should be vei-y glad to receive the drawings 
offered.—E d] 
PRINCIPLES OF BREEDING. 
We have been several times requested to say some¬ 
thing inregai-d to what is called “in and in ” breed¬ 
ing. We are by no means confident, however, that 
any remarks of ours can throw light on the subject; 
though often discussed, it is still involved in intri¬ 
cacy. In endeavoring to understand it, the first point 
to be settled, is the precise meaning of the term “ in- 
and-in” breeding. It seems to be understood vari¬ 
ously—as some suppose it to apply to animals of any 
degree of relationship—others apply it to breeding 
from the same family, without particularly defining the 
affinity of blood which animals bred together should 
possess to justify the use of the term. Thus they regard 
the produce of father and daughtei’, or mother and so i, 
as animals bred in-and-in; using the same term in this 
case as they would do in reference to the produce of 
brother and sister. But a strict definition is evidently 
necessary, otherwise the use of the term is wholly 
random, and its signification so uncertain that it con¬ 
veys only a vague idea. 
What, then, is in-and-in breeding? Sir John S. 
Sebright, in a letter on the “Art of Impi-oving the 
Breeds of Domestic Animals,” published some years 
since by the British Board of Agriculture, considers the 
term to signify breeding from animals of precisely the 
same blood. This is an intelligible, and we believe 
correct definition. It has also been assented to, and its 
adoption advocated with force, by John Hare Pow¬ 
ell, Esq., a citizen of our own country, who has in 
times past been eminently distinguished as a breeder 
of stock. 
Upon the basis of this definition it follows that no 
course of breeding can be strictly in-and-in except that 
which results from coupling animals of exactly the 
same blood, and this, probably, can rarely happen but 
by an union of brother and sister, or of animals which 
were originally derived from such an union. Where 
the original male and female were ol different families, 
it is obvious that the offspring does not possess the same 
blood of either of the parents, but has just half the 
blood of each. The produce of this offspring and either 
of the parents, would be three-fourths of one of the first 
pair, and one-fourth of the other. The next genera¬ 
tion, bred in the same way, would be seven-eighths of 
the parent. the next fifteen-sixteenths, and so on; the 
blood of one of the oidginal ancestors increasing and the 
other diminishing in this ratio with each generation. 
This and similar courses of breeding have been aptly 
denominated “ breeding in and the term “ close breed¬ 
ing ” is also more or less applicable, according to the 
nearness of relationship existing between animals coup¬ 
led together, or according to the extent to which breed¬ 
ing in is carried. 
Having settled what is to be understood by the term 
“ in-and-in,” we will proceed to consider the expedien¬ 
cy of that course of breeding. And it may be observed 
in the first place, that although many distinguished 
breeders have advocated and followed, more or less, 
breeding in, or close breeding, very few, if any, have 
recommended in-and-in breeding, as here defined.* The 
effects of the course when carried on for several genera- 
tions, cannot perhaps be better described than in the 
language of Sebright, in the essay above referred to. 
“ I have,” says he, “ tried many experiments by breed¬ 
ing- in-and-in, upon dogs, fowls, and pigeons; the dogs 
became from strong spaniels, weak and diminutive lap- 
dogs; the fowls became long in the legs, small in 
the body, and bad feeders. * * * Indeed I have no 
doubt but that by this px-actice being continued, animals 
would, in coui-se of time, degenerate to such a degree 
as to become incapable of breeding at all.” 
It is a maxim in physics that an effect is not produced 
without a cause. Hence it is natural to ask a reason 
for the ill effects alleged to be produced by in-and-in 
breeding. We will endeavor to give one, which, 
though not entirely original, is in some respects diffe¬ 
rent fi-om any we have seen offered. 
It is admitted that different families of animals have 
certain hereditai-y tendencies. The proneness to par¬ 
ticular diseases in families of the human x-ace, is evi¬ 
dence of this. Now it is plain that where two animals 
of the same blood and the same hereditary tendencies, 
are coupled together, there would be a greater liability 
in the progeny to exhibit any defect or disease which 
belonged to the family, than there would be if only one 
of the parents had this constitutional tendency. Hence 
we see the defects of parents augmented in the pro¬ 
geny. 
This we believe to be the true cause of the degene- 
x-acy which ensues from in-and-in breeding. But let 
us not be misunderstood. It is not merely the nearness 
of relationship which produces these consequences; 
for we can readily believe that they might follow’ 
where the parents wei’e not at all connected by consan¬ 
guinity. The animals might belong to families wholly 
distinct, and yet their hereditary tendencies be similar. 
For example : let there be chosen a bull and cow wholly 
unrelated, or even of different breeds, each of which 
has disease of the liver to the same degree, and each 
also an equal hereditary tendency to that disease; the 
progeny generated by two such animals would no doubt 
have the same predisposition to the defect or disease 
of the parent as if both the latter had been of the 
same family. Thus the degeneracy of offspring is not 
owing to the relationship, simply, but to the natural 
defects of the parents or ancestors. The skillful breeder 
will therefore select his animals for propagation with a 
* It is proper to remark that breeding in when carried to a 
certain extent, may be expected to produce result-; similar to those 
of breeding in-and-in ; that is, the consequences of the former 
will resemble those of the latter system, in proportion as the b.lood 
of the animals bred together becomes similar. 
