ty, and drove away the
tendency to malformation in the tail. I have heard the particulars of
another case with bloodhounds, in which the female had to be held to
the male. Considering how rapid is the natural increase of the dog, it
is difficult to understand the high price of most highly improved
breeds, which almost implies long-continued close interbreeding, except
on the belief that this process lessens fertility and increases
liability to distemper and other diseases. A high authority, Mr.
Scrope, attributes the rarity and deterioration in size of the Scotch
deerhound (the few individuals now existing throughout the country
being all related) in large part to close interbreeding.

With all highly-bred animals there is more or less difficulty in
getting them to procreate quickly, and all suffer much from delicacy of
constitution; but I do not pretend that these effects ought to be
wholly attributed to close interbreeding. A great judge of rabbits[260]
says, "the long-eared does are often too highly bred or forced in their
youth to be of much value as breeders, often turning out barren or bad
mothers." Again: "Very long-eared bucks will also sometimes prove
barren." These highly-bred rabbits often desert their young, so that it
is necessary to have nurse-rabbits.

With _Pigs_ there is more unanimity amongst breeders on the evil
effects of close interbreeding than, perhaps, with any other large
animal. Mr. Druce, a great and successful breeder of the Improved
Oxfordshires (a crossed race), writes, "without a change of boars of a
different tribe, but of the same breed, constitution cannot be
preserved." Mr. Fisher Hobbs, the raiser of the celebrated Improved
Essex breed, divided his stock into three separate families, by which
means he maintained the breed for more than twenty years, "by judicious
selection from the _three distinct families_."[261] Lord Western was
the first importer of a Neapolitan boar and sow. "From this pair he
bred in-and-in, until the breed was in danger of becoming extinct, a
sure result (as Mr. Sidney remarks) of in-and-in breeding." Lord
Western then crossed his Neapolitan pigs with the old Essex, and made
the first great step towards the Improved Essex breed. Here is a more
interesting case. Mr. J. Wright, well known as a breeder, crossed[262]
the same bo