alian cousins.
In Europe and Asia the opossums lived on lustily, in spite of
competition, during the whole of the Eocene period, side by side with
hog-like creatures not yet perfectly piggish, with nondescript animals,
half horse half tapir, and with hornless forms of deer and antelopes,
unprovided, so far, with the first rudiment of budding antlers. But in
the succeeding age they seem to disappear from the eastern continent,
though in the western, thanks to their hand-like feet, opposable thumb,
and tree-haunting life, they still drag out a precarious existence in
many forms from Virginia to Chili, and from Brazil to California. It is
worth while to notice, too, that whereas the kangaroos and other
Australian marsupials are proverbially the very stupidest of mammals,
the opossums, on the contrary, are well known to those accurate
observers of animal psychology, the plantation negroes, to be the very
cleverest, cunningest, and slyest of American quadrupeds. In the fierce
struggle for life of the crowded American lowlands, the opossum was
absolutely forced to acquire a certain amount of Yankee smartness, or
else to be improved off the face of the earth by the keen competition of
the pouchless mammals.

Up to the day, then, when Captain Cook and Sir Joseph Banks, landing for
the first time on the coast of New South Wales, saw an animal with short
front limbs, huge hind legs, a monstrous tail, and a curious habit of
hopping along the ground (called by the natives a kangaroo), the
opossums of America were the only pouched mammals known to the European
world in any part of the explored continents. Australia, severed from
all the rest of the earth--_penitus toto orbe divisa_--ever since the
end of the secondary period, remained as yet, so to speak, in the
secondary age so far as its larger life-elements were concerned, and
presented to the first comers a certain vague and indefinite picture of
what 'the world before the flood' must have looked like. Only it was a
very remote flood; an antediluvian age separated from our own not by
thousands, but by millions, of seasons.

To this rough approximate statement, however, sundry needful
qualifications must be made at the very outset. No statement is ever
quite correct until you have contradicted in minute detail about
two-thirds of it.

In the first place there are a good many modern elements in the
indigenous population of Australia; but then they are elements of the
stray and