PRE-GLACIAL EPOCHS.
The age immediately preceding the glacial, and consequently the
post-tertiary, is known as the pliocene epoch, the last of the tertiary.
The tertiary period began with the close of the cretaceous. A map of the
early tertiary period would represent parts of Maryland, Virginia, the
Carolinas, Georgia, the whole of Florida, the lower parts of Alabama,
Mississippi, Texas, the whole of Louisiana, and the adjoining territory
on both sides of the Mississippi, as far as Cairo, as covered with
water. Also a great sea extending through Nebraska and the western part
of Dacotah, and taking a north-westerly course until it emptied into the
Pacific. In Europe, the great basin of Paris (excepting a zone of
chalk), the greater part of Spain and Italy, the whole of Belgium,
Holland, Prussia, Switzerland, Hungary, Wallachia, and northern Russia,
as one vast sheet of water. England and France were connected by a band
of rocks.
About the middle of the tertiary, a tropical climate and tropical fauna
and flora spread over the whole of Europe. Palms, cedars, laurels, and
cinnamon trees flourished in the valleys of Switzerland, and more than
thirty different species of oak adorned the forests of that time.
In Europe, in the eocene, there have been found thirty species of
crocodiles; many species of snakes, one twenty feet long; a dozen
species of birds; tapirs (_Palaeothere_ and _Lophiodon_), two species of
hogs, some ruminants and rodents.
In the miocene, among _Pachyderms_ may be mentioned the mastodon,
elephant, dinothere (an elephantine animal), rhinoceros, hog, horse,
tapir, and hippopotamus; among _Carnivores_, the machairodus, hyena,
lion, and dog; among _Ruminants_, the camel, deer, and antelope. There
were monkeys, and many other animals.
In the pliocene, besides those enumerated, are found the bear, hare, and
other animals.
In the tertiary beds of America have been found mastodons, elephants,
rhinoceroses, deer, camels, foxes, wolves, horses, whales, and other
mammalia.
Owing to the great lapse of time it cannot be expected that many traces
of man will be discovered in this early period.
Upon theoretical grounds Lyell thought it very probable that man lived
in the pliocene; but in relation to miocene time, he says, "Had some
other rational being, representing man, then flourished, some signs of
his existence could hardly have escaped unnoticed, in the shape of
implements of stone or metal, more frequent and more durable than the
osseous remains of any of the mammalia."[49] Sir J. Lubbock, while
admitting the existence of man in the pliocene, goes farther and says,
"If man constitutes a separate family of mammalia, as he does in the
opinion of the highest authorities, then, according to all
palaeontological analogies, he must have had representatives in miocene
times. We need not, however, expect to find the proofs in Europe; our
nearest relatives in the animal kingdom are confined to hot, almost to
tropical climates, and it is in such countries that we are most likely
to find the earliest traces of the human race."[50] Alfred R. Wallace
out-distances any of his cotemporaries, for he says, "We are enabled to
place the origin of man at a much more remote geological epoch than has
yet been thought possible. He may even have lived in the miocene or
eocene period, when not a single mammal was identical in form with any
existing species."[51]
Some of the older and some of the recent discoveries of geologists have
settled the question of tertiary man; and the "signs of his existence,"
in the "shape of implements of stone," as demanded by Lyell, have been
furnished.
_Man in the Pliocene._--It has already been intimated that the evidences
of man are but few in this early epoch. The first example, in the
following list, borders closely on the glacial, but far enough removed
as to be referred to the pliocene.
In the construction of a canal between Stockholm and Gothenburg it was
necessary to cut through one of those hills called _osars_, or erratic
blocks, which were deposited by the drift-ice during the glacial epoch.
Beneath an immense accumulation of osars, with shells and sand, there
was discovered in the deepest layer of subsoil, at a depth of about
sixty feet, a circular mass of stones, forming a hearth, in the middle
of which there were wood-coals. No other hand than that of man could
have performed the work.[52]
In the pliocene beds in the neighborhood of the town of Savonia in
Liguria, M. A. Issel found several bones which presented all the
physical signs of very high antiquity. Dr. Buchner is of the opinion
that before these bones can be employed as satisfactory evidence they
must have a more accurate test by scientific authorities.[53]
In the upper pliocene beds at St. Prest (France), M. Desnoyers found
traces of human action on the bones of animals belonging to the
tertiary. These fractures are analogous to those of human action
observed on bones from the glacial period, and identical with those made
by northern tribes of the present day, on the skulls of ruminants. The
marked bones found were those of the Southern elephant (_E.
meridionalis_), rhinoceros (_R. leptorinus_), hippopotamus major,
several species of deer, and two of the ox. Carl Vogt states that this
discovery is not only genuine, but also, the formation in which the
bones were found is decidedly tertiary. It is further characterized by
the presence of the southern elephant (_E. meridionalis_). As this
elephant became extinct before the glacial age, the bones consequently
precede the glacial, and the age of the cave-bear, the mammoth, and
tichorrhine rhinoceros. The eminent French naturalist, Quatrefages,
confirms the testimony of Desnoyers.[54]
The conclusions of Desnoyers are confirmed beyond a doubt by the more
recent discoveries of Abbe Bourgeois. In the same tertiary strata of St.
Prest, in which were found the marked or fractured bones, Bourgeois
discovered worked flints, including flakes, awls, and scrapers.[55]
A human skull, belonging to the pliocene, was found by James Matson, at
Altaville, in Calaveras county, California, at a depth of one hundred
and thirty feet, under five beds of gravel separated by five layers of
lava, associated with the bones of an extinct rhinoceros, camel, and
horse. The base of the skull is imbedded in a mass of bone-breccia and
small pebbles of volcanic rock. The shape of the skull resembles that of
the Digger Indians, and is of remarkable thickness.[56]
_Man in the Miocene._[57]--M. Bourgeois has found, in a stratum of
miocene near Pontlevoy, numerous worked flints, and other flints which
have been subjected to the action of heat. These works of man were
associated with the remains of the acerotherium (an extinct species
allied to the rhinoceros), and beneath five distinct beds, one of which
contained the rolled bones of rhinoceros, mastodon, and dinotherium.[58]
M. Tardy found a flint-flake of undoubted workmanship in the miocene
beds of Aurillac (Auvergne), together with the remains of _dinotherium
giganteum_, and _machaerodus latidens_.[59]
M. Bourgeois reports that Abbe Delaunay had found near Pouance
(Maine-et-Loire), fossil bones of a _halitherium_ (an herbivorous
cetacean of the miocene), with evident signs of having been operated
upon by cutting instruments.[60]
In the miocene gravel beds of Colorado and Wyoming territories,
chert-flakes, hammers, chisels, knives, and wrought shells have been
found.[61]
_Eocene._--As yet geologists have failed to discover any traces of man
in the Eocene epoch.