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1859
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1859
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1 blocks not present in 1866 1869; present in 1859 1860 1861 1872
There can be no doubt that a race may be modified by occasional crosses, if aided by the careful selection of those individual mongrels, which present any desired character; but that a race could be obtained nearly intermediate between two extremely different races or speceies, I can hardly believe.

and 1859 1860 1861 1866 1869
in character, and 1872

OMIT 1869 1872
or rather utter hopelessness, 1859 1860 1861
or rather utter hopelessness 1866

Pigeon, their Differences and Origin . 1866 1869
Pigeon .— 1859 1860 1861
Pigeon , their Differences and Origin . 1872

distinct races by crossing has been greatly exaggerated. Many cases are on record, showing that a race may be modified by occasional crosses, if aided by the careful selection of the individuals which present the desired character; but to obtain a race nearly intermediate between two extremely different races or species, would be very difficult. Sir J. Sebright expressly
experimentised
experimented
with
for
this object, and failed. The offspring from the first cross between two pure breeds is tolerably and sometimes (as I have found with pigeons)
quite
extremely
uniform
uniform,
and everything seems simple enough; but when these mongrels are crossed one with another for several generations, hardly two of them
will be
are
alike,
alike;
and then the
extreme
extreme
difficulty,
difficulty
OMIT of the task becomes
manifest.
apparent.
Cer- tainly,
Certainly,
a breed intermediate between two very distinct breeds could not be got without extreme care and long-continued selection; nor can I find a
single
....
case on record of a permanent race having been thus formed.
On the
....
Breeds of the Domestic Pigeon, their Differences and Origin .
Believing that it is always best to study some special group, I have, after deliberation, taken up domestic pigeons. I have kept every breed which I could purchase or obtain, and have been most kindly favoured with skins from several quarters of the world, more especially by the Hon. W. Elliot from India, and by the Hon. C. Murray from Persia. Many treatises in different languages have been published on pigeons, and some of them are very important, as being of
con- siderable
considerable
antiquity. I have associated with several eminent fanciers, and have been permitted to join two of the London Pigeon Clubs. The diversity of the breeds is something astonishing. Compare the English carrier and the short-faced tumbler, and see the wonderful
difference
dif- ference