nal extinction. Thus the
intermediate links are lost, and breeds which have already diverged gain
Distinctness of Character.

In the chapters on the Pigeon, it was proved by historical details and by
the existence of connecting sub-varieties in distant lands that several
breeds have steadily diverged in character, and that many old and
intermediate sub-breeds have become extinct. Other cases could be adduced
of the extinction of domestic breeds, as of the Irish wolf-dog, the old
English hound, and of two breeds in France, one of which was formerly
highly valued.[931] Mr. Pickering remarks[932] that "the sheep figured on
the most ancient Egyptian monuments is unknown at the present day; and at
least one variety of the bullock, formerly known in Egypt, has in like
manner become extinct." So it has been with some animals, and with several
plants cultivated by the ancient inhabitants of Europe during the neolithic
period. In Peru, Von Tschudi[933] found in certain tombs, apparently prior
to the dynasty of the Incas, two kinds of maize not now known in the
country. With our flowers and culinary vegetables, {426} the production of
new varieties and their extinction has incessantly recurred. At the present
time improved breeds sometimes displace at an extraordinarily rapid rate
older breeds; as has recently occurred throughout England with pigs. The
Long-horn cattle in their native home were "suddenly swept away as if by
some murderous pestilence," by the introduction of Short-horns.[934]

What grand results have followed from the long-continued action of
methodical and unconscious selection, checked and regulated to a certain
extent by natural selection, is seen on every side of us. Compare the many
animals and plants which are displayed at our exhibitions with their
parent-forms when these are known, or consult old historical records with
respect to their former state. Almost all our domesticated animals have
given rise to numerous and distinct races, excepting those which cannot be
easily subjected to selection--such as cats, the cochineal insect, and the
hive-bee,--and excepting those animals which are not much valued. In
accordance with what we know of the process of selection, the formation of
our many races has been slow and gradual. The man who first observed and
preserved a pigeon with its oesophagus a little enlarged, its beak a little
longer, or its tail a little more expanded than usual, never dreamed that
he had m