but certainly)
Niata cattle, turnspit and pug dogs, jumper and frizzled fowls, short-faced
tumbler pigeons, hook-billed ducks, &c., and a multitude of vegetable
varieties, have suddenly appeared in nearly the same state as we now see
them.[88] Lastly, Mr. Darwin tells us, that there has been an occasional
development (in five distinct cases) in England of the "japanned" or
"black-shouldered peacock" (_Pavo nigripennis_), a distinct species,
according to Dr. Sclater,[89] yet arising in Sir J. Trevelyan's flock
composed entirely of the common kind, and increasing, "_to the extinction
of the previously existing breed_."[90] Mr. Darwin's only explanation of
the phenomena (on the supposition of the species being distinct) is by{101}
reversion, owing to a supposed ancestral cross. But he candidly admits, "I
have heard of no other such case in the animal or vegetable kingdom." On
the supposition of its being only a variety, he observes, "The case is the
most remarkable ever recorded of the abrupt appearance of a new form, which
so closely resembles a true species, that it has deceived one of the most
experienced of living ornithologists."

As to plants, M. C. Naudin[91] has given the following instances of the
sudden origination of apparently permanent forms. "The first case mentioned
is that of a poppy, which took on a remarkable variation in its fruit--a
crown of secondary capsules being added to the normal central capsule. A
field of such poppies was grown, and M. Goeppert, with seed from this field,
obtained still this monstrous form in great quantity. Deformities of ferns
are sometimes sought after by fern-growers. They are now always obtained by
taking spores from the abnormal parts of the monstrous fern; from which
spores ferns presenting the same peculiarities invariably grow.... The most
remarkable case is that observed by Dr. Godron, of Nancy. In 1861 that
botanist observed, amongst a sowing of _Datura tatula_, the fruits of which
are very spinous, a single individual of which the capsule was perfectly
smooth. The seeds taken from this plant all furnished plants having the
character of this individual. The fifth and sixth generations are now
growing without exhibiting the least tendency to revert to the spinous
form. More remarkable still, when crossed with the normal _Datura tatula_,
hybrids were produced, which, in the second generation, reverted to the
original types, as true hybrids do."

There are, then, abundan