species of wild dogs have concurred in the formation of the different
breeds of dogs as we now have them.

In the lacustrine habitations of the stone age in Sweden, and in the
_kjoekkenmoedding_ (kitchen remains) of Denmark, of the same epoch, we
find the remains of a dog, which, according to Rutymeyer, belongs to a
breed which is constant up to its least details, and which is of a
light and elegant conformation, of medium size, with a spacious and
rounded cranium and a short, blunt muzzle, and a medium sized jaw, the
teeth of which form a regular series.

This dog, which has been named by geologists _Canis palustris_, fully
resembles in size, slenderness of the limbs, and weakness of the
muscular insertions, the spaniel, the brach hound, or the griffon.

This dog of the stone age is entirely distinct from the wolf and
jackal, of which some regard the domestic dog as a descendant, and as
it has appeared in Denmark as well as in Sweden, there is no doubt
that this species, peculiar to Europe, was subjugated by man and used
by him, in the first place, for hunting, and later on for guarding
houses and cattle. Later still, in the age of metals, we observe the
appearance, both in Denmark and Sweden, of larger and stronger breeds
of dogs, having in their jaws the character of mastiffs, and probably
introduced by the first emigrants from Asia.

There are, moreover, historic proofs that the dogs of the strongest
breeds are indigenous to Asia, where we still find the dog of Thibet,
the most colossal of all; in fact, in Pliny we read the following
narrative: Alexander the Great received from a king of Asia a dog of
huge size. He wished to pit it against bears and wild boars, but the