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Variation of Animals and Plants under Domestication, the — Volume 2 by Charles Darwin
page 61 of 776 (07%)
horns and fleece to its crossed offspring, and the bull the presence or
absence of horns.

In the following chapter on Crossing I shall have occasion to show that
certain characters are rarely or never blended by crossing, but are
transmitted in an unmodified state from either parent-form; I refer to this
fact here because it is sometimes accompanied on the one side by prepotency,
which thus acquires the false appearance of unusual strength. In the same
chapter I shall show that the rate at which a species or breed absorbs and
obliterates another by repeated crosses, depends in chief part on prepotency
in transmission.]

In conclusion, some of the cases above given,--for instance, that of the
trumpeter pigeon,--prove that there is a wide difference between mere
inheritance and prepotency. This latter power seems to us, in our ignorance,
to act in most cases quite capriciously. The very same character, even though
it be an abnormal or monstrous one, such as silky feathers, may be transmitted
by different species, when crossed, either with prepotent force or singular
feebleness. It is obvious, that a purely-bred form of either sex, in all cases
in which prepotency does not run more strongly in one sex than the other, will
transmit its character with prepotent force over a mongrelised and already
variable form. (14/21. See some remarks on this head with respect to sheep by
Mr. Wilson in 'Gardener's Chronicle' 1863 page 15. Many striking instances of
this result are given by M. Malingie-Nouel 'Journ. R. Agricult. Soc.' volume
14 1853 page 220 with respect to crosses between English and French sheep. He
found that he obtained the desired influence of the English breeds by crossing
intentionally mongrelised French breeds with pure English breeds.) From
several of the above-given cases we may conclude that mere antiquity of
character does not by any means necessarily make it prepotent. In some cases
prepotency apparently depends on the same character being present and visible
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