s are the hardiest
and most easily reared.[275] Mr. Tegetmeier, who has carefully attended
to poultry of all breeds, says[276] that Dorking hens, allowed to run
with Houdan or Crevecoeur cocks, "produce in the early spring chickens
that for size, hardihood, early maturity, and fitness for the market,
surpass those of any pure breed that we have ever raised." Mr. Hewitt
gives it as a general rule with fowls, that crossing the breed
increases their size. He makes this remark after stating that hybrids
from the pheasant and fowl are considerably larger than either
progenitor: so again, hybrids from the male golden pheasant and hen
common pheasant "are of far larger size than either parent-bird."[277]
To this subject of the increased size of hybrids I shall presently
return.

With _Pigeons_, breeders are unanimous, as previously stated, that it
is absolutely indispensable, notwithstanding the trouble and expense
thus caused, occasionally to cross their much-prized birds with
individuals of another strain, but belonging, of course, to the same
variety. It deserves {126} notice that, when large size is one of the
desired characters, as with pouters,[278] the evil effects of close
interbreeding are much sooner perceived than when small birds, such as
short-faced tumblers, are valued. The extreme delicacy of the high
fancy breeds, such as these tumblers and improved English carriers, is
remarkable; they are liable to many diseases, and often die in the egg
or during the first moult; and their eggs have generally to be hatched
under foster-mothers. Although these highly-prized birds have
invariably been subjected to much close interbreeding, yet their
extreme delicacy of constitution cannot perhaps be thus fully
explained. Mr. Yarrell informed me that Sir J. Sebright continued
closely interbreeding some owl-pigeons, until from their extreme
sterility he as nearly as possible lost the whole family. Mr.
Brent[279] tried to raise a breed of trumpeters, by crossing a common
pigeon, and recrossing the daughter, granddaughter,
great-granddaughter, and great-great-granddaughter, with the same male
trumpeter, until he obtained a bird with 15/16ths of trumpeter's blood;
but then the experiment failed, for "breeding so close stopped
reproduction." The experienced Neumeister[280] also asserts that the