at the goose has varied in some
degree, we may infer from naturalists not being unanimous with respect to
its wild parent-form; though the difficulty is chiefly due to the existence
of three or four closely allied wild European species[456]. A large
majority of capable judges are convinced that our geese are descended from
the wild Grey-lag goose (_A. ferus_); the young of which can easily be
tamed,[457] and are domesticated by the Laplanders. This species, when
crossed with the domestic goose, produced in the Zoological Gardens, as I
was assured in {288} 1849, perfectly fertile offspring.[458] Yarrell[459]
has observed that the lower part of the trachea of the domestic goose is
sometimes flattened, and that a ring of white feathers sometimes surrounds
the base of the beak. These characters seem at first good indications of a
cross at some former period with the white-fronted goose (_A. albifrons_);
but the white ring is variable in this latter species, and we must not
overlook the law of analogous variation; that is, of one species assuming
some of the characters of allied species.

As the goose has proved so inflexible in its organization under
long-continued domestication, the amount of variation which can be detected
is worth giving. It has increased in size and in productiveness;[460] and
varies from white to a dusky colour. Several observers[461] have stated
that the gander is more frequently white than the goose, and that when old
it almost invariably becomes white; but this is not the case with the
parent-form, the _A. ferus_. Here, again, the law of analogous variation
may have come into play, as the snow-white male of the Rock-Goose
(_Bernicla antarctica_) standing on the sea-shore by his dusky partner is a
sight well known to all those who have traversed the sounds of Tierra del
Fuego and the Falkland Islands. Some geese have topknots; and the skull
beneath, as before stated, is perforated. A sub-breed has lately been
formed with the feathers reversed at the back of the head and neck.[462]
The beak varies a little in size, and is of a yellower tint than in the
wild species; but its colour and that of the legs are both slightly
variable.[463] This latter fact deserves attention, because the colour of
the legs and beak is highly serviceable in discriminating the several
closely allied wild forms.[464] At our {289} Shows two breeds are
exhibited; viz. the Embden and Toulouse; but they differ in nothing except
col