ly be desired. If we reject this evidence, and
believe that the japanned peacock is a distinct species, we must suppose in
all these cases that the common breed had at some former period been
crossed with the supposed _P. nigripennis_, but had lost every trace of the
cross, yet that the birds occasionally produced offspring which suddenly
and completely reacquired through reversion the characters of _P.
nigripennis_. I have heard of no other such case in the animal or vegetable
kingdom. To perceive the full improbability of such an occurrence, we may
suppose that a breed of dogs had been crossed at some former period with a
wolf, but had lost every trace of the wolf-like character, yet that the
breed gave birth in five instances in the same country, within no great
length of time, to a wolf perfect in every character; and we must further
suppose that in two of the cases the newly produced wolves afterwards
spontaneously increased to such an extent as to lead to the extinction of
the parent-breed of dogs. So remarkable a form as the _P. nigripennis_,
when first imported, would have realized a large price; it is therefore
improbable that it should have been silently introduced and its history
subsequently lost. On the whole the evidence seems to me, as it did to Sir
R. Heron, to preponderate strongly in favour of the black-shouldered breed
being a variation, induced either by the climate of England, or by some
unknown cause, such as reversion to a primordial and extinct condition of
the species. On the view that the black-shouldered {292} peacock is a
variety, 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.

THE TURKEY.

IT seems fairly well established by Mr. Gould,[470] that the turkey, in
accordance with the history of its first introduction, is descended from a
wild Mexican species (_Meleagris Mexicana_) which had been already
domesticated by the natives before the discovery of America, and which
differs specifically, as it is generally thought, from the common wild
species of the United States. Some naturalists, however, think that these
two forms should be ranked only as well-marked geographical races. However
this may be, the case deserves notice because in the United States wild
male turkeys sometimes court the domestic hens, which are descended from
the Mexican