THE POST-PLIOCENE PERIOD--_Continued_.
As regards the _life_ of the Post-Pliocene period, we have, in
the first place, to notice the effect produced throughout the
northern hemisphere by the gradual supervention of the Glacial
period. Previous to this the climate must have been temperate or
warm-temperate; but as the cold gradually came on, two results were
produced as regards the living beings of the area thus affected.
In the first place, all those Mammals which, like the Mammoth, the
Woolly Rhinoceros, the Lion, the Hyæna, and the Hippopotamus,
require, at any rate, moderately warm conditions, would be forced
to migrate southwards to regions not affected by the new state
of things. In the second place, Mammals previously inhabiting
higher latitudes, such as the Reindeer, the Musk-ox, and the
Lemming, would be enabled by the increasing cold to migrate
southwards, and to invade provinces previously occupied by the
Elephant and the Rhinoceros. A precisely similar, but more
slowly-executed process, must have taken place in the sea, the
northern Mollusca moving southwards as the arctic conditions of
the Glacial period became established, whilst the forms proper
to temperate seas receded. As regards the readily locomotive
Mammals, also, it is probable that this process was carried on
repeatedly in a partial manner, the southern and northern forms
alternately fluctuating backwards and forwards over the same
area, in accordance with the fluctuations of temperature which
have been shown by Mr James Geikie to have characterised the
Glacial period as a whole. We can thus readily account for the
intermixture which is sometimes found of northern and southern
types of Mammalia in the same deposits, or in deposits apparently
synchronous, and within a single district. Lastly, at the final close
of the arctic cold of the Glacial period, and the re-establishment
of temperate conditions over the northern hemisphere, a reversal
of the original process took place--the northern Mammals retiring
within their ancient limits, and the southern forms pressing
northwards and reoccupying their original domains.
The _Invertebrate_ animals of the Post-Pliocene deposits require
no further mention--all the known forms, except a few of the shells
in the lowest beds of the formation, being identical with species
now in existence upon the globe. The only point of importance in
this connection has been previously noticed--namely, that in
the true Glacial deposits themselves a considerable number of
the shells belong to northern or Arctic types.
As regards the _Vertebrate_ animals of the period, no extinct
forms of Fishes, Amphibians, or Reptiles are known to occur,
but we meet with both extinct Birds and extinct Mammals. The
remains of the former are of great interest, as indicating the
existence during Post-Pliocene times, at widely remote points
of the southern hemisphere, of various wingless, and for the
most part gigantic, Birds. All the great wingless Birds of the
order _Cursores_ which are known as existing at the present day
upon the globe, are restricted to regions which are either wholly
or in great part south of the equator. Thus the true Ostriches are
African; the Rheas are South American; the Emeus are Australian;
the Cassowaries are confined to Northern Australia, Papua, and the
Indian Archipelago; the species of _Apteryx_ are natives of New
Zealand; and the Dodo and Solitaire (wingless, though probably
not true _Cursores_), both of which have been exterminated within
historical times, were inhabitants of the islands of Mauritius
and Rodriguez, in the Indian Ocean. In view of these facts, it
is noteworthy that, so far as known, all the Cursorial Birds
of the Post-Pliocene period should have been confined to the
same hemisphere as that inhabited by the living representatives
of the order. It is still further interesting to notice that
the extinct forms in question are only found in geographical
provinces which are now, or have been within historical times,
inhabited by similar types. The greater number of the remains
of these have been discovered in New Zealand, where there now
live several species of the curious wingless genus _Apteryx_;
and they have been referred by Professor Owen to several generic
groups, of which _Dinornis_ is the most important (fig. 257).
Fourteen species of _Dinornis_ have been described by the
distinguished palæontologist just mentioned, all of them being
large wingless birds of the type of the existing Ostrich, having
enormously powerful hind-limbs adapted for running, but with
the wings wholly rudimentary, and the breast-bone devoid of the
keel or ridge which characterises this bone in all birds which
fly. The largest species is the _Dinornis giganteus_, one of
the most gigantic of living or fossil birds, the shank (tibia)
measuring a yard in length, and the total height being at least
ten feet. Another species, the _Dinornis Elephantopus_ (fig.
257), though not standing more than about six feet in height,
was of an even more ponderous construction--"the framework of
the skeleton being the most massive of any in the whole class of
Birds," whilst "the toe-bones almost rival those of the Elephant"
(Owen). The feet in _Dinornis_ were furnished with three toes,
and are of interest as presenting us with an undoubted Bird big
enough to produce the largest of the foot-prints of the Triassic
Sandstones of Connecticut. New Zealand has now been so far explored,
that it seems questionable if it can retain in its recesses any
living example of _Dinornis_; but it is certain that species
of this genus were alive during the human period, and survived
up to quite a recent date. Not only are the bones very numerous
in certain localities, but they are found in the most recent
and superficial deposits, and they still contain a considerable
proportion of animal matter; whilst in some instances bones have
been found with the feathers attached, or with the horny skin of
the legs still adhering to them. Charred bones have been found
in connection with native "ovens;" and the traditions of the
Maories contain circumstantial accounts of gigantic wingless
Birds, the "Moas," which were hunted both for their flesh and
their plumage. Upon the whole, therefore, there can be no doubt
but that the Moas of New Zealand have been exterminated at quite a
recent period--perhaps within the last century--by the unrelenting
pursuit of Man,--a pursuit which their wingless condition rendered
them unable to evade.
[Illustration: Fig. 257.--Skeleton of _Dinornis elephantopus_,
greatly reduced. Post-Pliocene, New Zealand. (After Owen.)]
In Madagascar, bones have been discovered of another huge wingless
Bird, which must have been as large as, or larger than, the _Dinornis
giganteus_, and which has been described under the name of _Æpiornis
maximus_. With the bones have been found eggs measuring from
thirteen to fourteen inches in diameter, and computed to have
the capacity of three Ostrich eggs. At least two other smaller
species of _Æpiornis_ have been described by Grandidier and
Milne-Edwards as occurring in Madagascar; and they consider the
genus to be so closely allied to the _Dinornis_ of New Zealand,
as to prove that these regions, now so remote, were at one time
united by land. Unlike New Zealand, where there is the _Apteryx_,
Madagascar is not known to possess any living wingless Birds;
but in the neighbouring island of Mauritius the wingless Dodo
(_Didus ineptus_) has been exterminated less than three hundred
years ago; and the little island of Rodriguez, in the same
geographical province, has in a similar period lost the equally
wingless Solitaire (_Pezophaps_), both of these, however, being
generally referred to the _Rasores_.
The _Mammals_ of the Post-Pliocene period are so numerous, that
in spite of the many points of interest which they present, only
a few of the more important forms can be noticed here, and that
but briefly. The first order that claims our attention is that
of the _Marsupials_, the headquarters of which at the present
day is the Australian province. In Oolitic times Europe possessed
its small Marsupials, and similar forms existed in the same area
in the Eocene and Miocene periods; but if size be any criterion,
the culminating point in the history of the order was attained
during the Post-Pliocene period in Australia. From deposits of
this age there has been disentombed a whole series of remains of
extinct, and for the most part gigantic, examples of this group
of Quadrupeds. Not to speak of Wombats and Phalangers, two forms
stand out prominently as representatives of the Post-Pliocene
animals of Australia. One of these is _Diprotodon_ (fig. 258),
representing, with many differences, the well-known modern group
of the Kangaroos. In its teeth, _Diprotodon_ shows itself to
be closely allied to the living, grass-eating Kangaroos; but
the hind-limbs were not so disproportionately long. In size,
also, _Diprotodon_ must have many times exceeded the dimensions
of the largest of its living successors, since the skull measures
no less than three feet in length. The other form in question
is _Thylacoleo_ (fig. 259), which is believed by Professor Owen
to belong to the same group as the existing "Native Devil"
(_Dasyurus_) of Van Diemen's Land, and therefore to have been
flesh-eating and rapacious in its habits, though this view is
not accepted by others. The principal feature in the skull of
_Thylacoleo_ is the presence, on each side of each jaw, of a
single huge tooth, which is greatly compressed, and has a cutting
edge. This tooth is regarded by Owen as corresponding to the
great cutting tooth of the jaw of the typical Carnivores, but
Professor Flower considers that _Thylacoleo_ is rather related to
the Kangaroo-rats. The size of the crown of the tooth in question
is not less than two inches and a quarter; and whether carnivorous
or not, it indicates an animal of a size exceeding that of the
largest of existing Lions.
[Illustration: Fig. 258.--Skull of _Diprotodon Australis_, greatly
reduced. Post-Pliocene, Australia.]
[Illustration: Fig. 259.--Skull of _Thylacoleo_. Post-Pliocene,
Australia. Greatly reduced. (After Flower.)]
The order of the _Edentates_, comprising the existing Sloths,
Ant-eaters, and Armadillos, and entirely restricted at the present
day to South America, Southern Asia, and Africa, is one alike
singular for the limited geographical range of its members, their
curious habits of life, and the well-marked peculiarities of
their anatomical structure. South America is the metropolis of
the existing forms; and it is an interesting fact that there
flourished within Post-Pliocene times in this continent, and to
some extent in North America also, a marvellous group of extinct
Edentates, representing the living Sloths and Armadillos, but
of gigantic size. The most celebrated of these is the huge
_Megatherium Cuvieri_ (fig. 260) of the South American Pampas.
The Megathere was a colossal Sloth-like animal which attained a
length of from twelve to eighteen feet, with bones more massive
than those of the Elephant. Thus the thigh-bone is nearly thrice
the thickness of the same bone in the largest of existing Elephants,
its circumference at its narrowest point nearly equalling its
total length; the massive bones of the shank (tibia and fibula)
are amalgamated at their extremities; the heel-bone (calcaneum)
is nearly half a yard in length; the haunch-bones (ilia) are
from four to five feet across at their crests; and the bodies
of the vertebræ at the root of the tail are from five to seven
inches in diameter, from which it has been computed that the
circumference of the tail at this part might have been from five
to six feet. The length of the fore-foot is about a yard, and
the toes are armed with powerful curved claws. It is known now
that the Megathere, in spite of its enormous weight and ponderous
construction, walked, like the existing Ant-eaters and Sloths,
upon the outside edge of the fore-feet, with the claws more or
less bent inwards towards the palm of the hand. As in the great
majority of the Edentate order, incisor and canine teeth are
entirely wanting, the front of the jaws being toothless. The
jaws, however, are furnished with five upper and four lower molar
teeth on each side. These grinding teeth are from seven to eight
inches in length, in the form of four-sided prisms, the crowns of
which are provided with well-marked transverse ridges; and they
continue to grow during the whole life of the animal. There are
indications that the snout was prolonged, and more or less flexible;
and the tongue was probably prehensile. From the characters of
the molar teeth it is certain that the Megathere was purely
herbivorous in its habits; and from the enormous size and weight
of the body, it is equally certain that it could not have imitated
its modern allies, the Sloths, in the feat of climbing, back
downwards, amongst the trees. It is clear, therefore, that the
Megathere sought its sustenance upon the ground; and it was
originally supposed to have lived upon roots. By a masterly piece
of deductive reasoning, however, Professor Owen showed that this
great "Ground-Sloth" must have truly lived upon the foliage of
trees, like the existing Sloths--but with this difference, that
instead of climbing amongst the branches, it actually uprooted
the tree bodily. In this _tour de force_, the animal sat upon its
huge haunches and mighty tail, as on a tripod, and then grasping
the trunk with its powerful arms, either wrenched it up by the
roots or broke it short off above the ground. Marvellous as this
may seem, it can be shown that every detail in the skeleton of the
Megathere accords with the supposition that it obtained its food
in this way. Similar habits were followed by the allied _Mylodon_
(fig. 261), another of the great "Ground-Sloths," which inhabited
South America during the Post-Pliocene period. In most respects,
the _Mylodon_ is very like the Megathere; but the crowns of the
molar teeth are flat instead of being ridged. The nearly-related
genus _Megalonyx_, unlike the Megathere, but like the Mylodon,
extended its range northwards as far as the United States.
[Illustration: Fig. 260.--_Megatherium Cuvieri_. Post-Pliocene,
South America.]
Just as the Sloths of the present day were formerly represented
in the same geographical area by the gigantic Megatheroids, so
the little banded and cuirassed Armadillos of South America were
formerly represented by gigantic species, constituting the genus
_Glyptodon_. The _Glyptodons_ (fig. 262) differed from the living
Armadillos in having no bands in their armour, so that they must
have been unable to roll themselves up. It is rare at the present
day to meet with any Armadillo over two or three feet in length;
but the length of the _Glyptodon clavipes_, from the tip of the
snout to the end of the tail, was more than nine feet.
[Illustration: Fig. 261.--Skeleton of _Mylodon robustus_.
Post-Pliocene, South America.]
[Illustration: Fig. 262.--Skeleton of _Glyptodon clavipes_.
Post-Pliocene, South America.]
There are no canine or incisor teeth in the _Glyptodon_, but
there are eight molars on each side of each jaw, and the crowns
of these are fluted and almost trilobed. The head is covered
by a helmet of bony plates, and the trunk was defended by an
armour of almost hexagonal bony pieces united by sutures, and
exhibiting special patterns of sculpturing in each species. The
tail was also defended by a similar armour, and the vertebræ were
mostly fused together so as to form a cylindrical bony rod. In
addition to the above-mentioned forms, a number of other Edentate
animals have been discovered by the researches of M. Lund in
the Post-Pliocene deposits of the Brazilian bone-caves. Amongst
these are true Ant-eaters, Armadillos, and Sloths, many of them
of gigantic size, and all specifically or generically distinct
from existing forms.
Passing over the aquatic orders of the _Sirenians_ and _Cetaceans_,
we come next to the great group of the Hoofed Quadrupeds, the
remains of which are very abundant in Post-Pliocene deposits both
in Europe and North America. Amongst the Odd-toed Ungulates the
most important are the Rhinoceroses, of which three species are
known to have existed in Europe during the Post-Pliocene period.
Two of these are the well-known Pliocene forms, the _Rhinoceros
Etruscus_ and the _R. Megarhinus_ still surviving in diminished
numbers; but the most famous is the _Rhinoceros tichorhinus_
(fig. 263), or so-called "Woolly Rhinoceros." This species is
known not only by innumerable bones, but also by a carcass, at
the time of its discovery complete, which was found embedded in
the frozen soil of Siberia towards the close of last century,
and which was partly saved from destruction by the exertions of
the naturalist Pallas. From this, we know that the Tichorhine
Rhinoceros, like its associate the Mammoth, was provided with
a coating of hair, and therefore was enabled to endure a more
severe climate than any existing species. The skin was not thrown
into the folds which characterise most of the existing forms;
and the technical name of the species refers to the fact that
the nostrils were completely separated by a bony partition. The
head carried two horns, placed one behind the other, the front
one being unusually large. As regards its geographical range,
the Woolly Rhinoceros is found in Europe in vast numbers north
of the Alps and Pyrenees, and it also abounded in Siberia; so
that it would appear to be a distinctly northern form, and to
have been adapted for a temperate climate. It is not known to
occur in Pliocene deposits, but it makes its first appearance
in the Pre-Glacial deposits, surviving the Glacial period, and
being found in abundance in Post-Glacial accumulations. It was
undoubtedly a contemporary of the earlier races of men in Western
Europe; and it may perhaps be regarded as being the actual
substantial kernel of some of the "Dragons" of fable.
[Illustration: Fig. 263.--Skull of the Tichorhine Rhinoceros, the
horns being wanting. One-tenth of the natural size. Post-Pliocene
deposits of Europe and Asia.]
The only other Odd-toed Ungulate which needs notice is the so-called
_Equus fossilis_ of the Post-Pliocene of Europe. This made its
appearance before the Glacial period, and appears to be in reality
identical with the existing Horse (_Equus caballus_). True Horses
also occur in the Post-Pliocene of North America; but, from some
cause or another, they must have been exterminated before historic
times.
[Illustration: Fig. 264--Skeleton of the "Irish Elk" (_Cervus
megaceros_). Post-Pliocene, Britain.]
Amongst the Even-toed Ungulates, the great _Hippopotamus major_
of the Pliocene still continued to exist in Post-Pliocene times
in Western Europe; and the existing Wild Boar (_Sus scrofa_),
the parent of our domestic breeds of Pigs, appeared for the first
time. The Old World possessed extinct representatives of its
existing Camels, and lost types of the living Llamas inhabited
South America. Amongst the Deer, the Post-Pliocene accumulations
have yielded the remains of various living species, such as the
Red Deer (_Cervus elaphus_), the Reindeer (_Cervus tarandus_),
the Moose or Elk (_Alces malchis_), and the Roebuck (_Cervus
capreolus_), together with a number of extinct forms. Among the
latter, the great "Irish Elk" (_Cervus megaceros_) is justly
celebrated both for its size and for the number and excellent
preservation of its discovered remains. This extinct species
(fig. 264) has been found principally in peat-mosses and
Post-Pliocene lake-deposits, and is remarkable for the enormous
size of the spreading antlers, which are widened out towards
their extremities, and attain an expanse of over ten feet from
tip to tip. It is not a genuine Elk, but is intermediate between
the Reindeer and the Fallow-deer. Among the existing Deer of the
Post-Pliocene, the most noticeable is the Reindeer, an essentially
northern type, existing at the present day in Northern Europe,
and also (under the name of the "Caribou") in North America. When
the cold of the Glacial period became established, this boreal
species was enabled to invade Central and Western Europe in great
herds, and its remains are found abundantly in cave-earths and
other Post-Pliocene deposits as far south as the Pyrenees.
[Illustration: Fig. 265.--Skull of the Urns (_Bos primigenius_).
Post-Pliocene and Recent. (After Owen.)]
In addition to the above, the Post-Pliocene deposits of Europe
and North America have yielded the remains of various Sheep and
Oxen. One of the most interesting of the latter is the "Urus" or
Wild Bull (_Bos primigenius_, fig. 265), which, though much larger
than any of the existing fossils, is believed to be specifically
undistinguishable from the domestic Ox (_Bos taurus_), and to be
possibly the ancestor of some of the larger European varieties
of oxen. In the earlier part of its existence the Urus ranged
over Europe and Britain in company with the Woolly Rhinoceros
and the Mammoth; but it long survived these, and does not appear
to have been finally exterminated till about the twelfth century.
Another remarkable member of the Post-Pliocene Cattle, also to
begin with an associate of the Mammoth and Rhinoceros, is the
European Bison or "Aurochs" (_Bison priscus_). This "maned" ox
formerly abounded in Europe in Post-Glacial times, and was not
rare even in the later periods of the Roman empire, though much
diminished in numbers, and driven back into the wilder and more
inaccessible parts of the country. At present this fine species
has been so nearly exterminated that it no longer exists in Europe
save in Lithuania, where its preservation has been secured by
rigid protective laws. Lastly, the Post-Pliocene deposits have
yielded the remains of the singular living animal which is known
as the Musk-ox or Musk-sheep (_Ovibos moschatus_). At the present
day, the Musk-ox is an inhabitant of the "barren grounds" of
Arctic America, and it is remarkable for the great length of
its hair. It is, like the Reindeer, a distinctively northern
animal; but it enjoyed during the Glacial period a much wider
range than it has at the present day, the conditions suitable
for its existence being then extended over a considerable portion
of the northern hemisphere. Thus remains of the Musk-Ox are found
in greater or less abundance in Post-Pliocene deposits over a
great part of Europe, extending even to the south of France;
and closely-related forms are found in similar deposits in the
United States.
[Illustration: Fig. 266.--Skeleton of the Mammoth (_Elephas
primigenius_). Portions of the integument still adhere to the
head, and the thick skin of the soles is still attached to the
feet. Post-Pliocene.]
Coming to the _Proboscideans_, we find that the _Mastodons_ seem
to have disappeared in Europe at the close of the Pliocene period,
or at the very commencement of the Post-Pliocene. In the New World,
on the other hand, a species of Mastodon (_M. Americanus_ or _M.
Ohioticus_) is found abundantly in deposits of Post-Pliocene
age, from Canada to Texas. Very perfect skeletons of this species
have been exhumed from morasses and swamps, and large individuals
attained a length (exclusive of the tusks) of seventeen feet and
a height of eleven feet, the tusks being twelve feet in length.
Remains of _Elephants_ are also abundant in the Post-Pliocene
deposits of both the Old and the New World. Amongst these, we
find in Europe the two familiar Pliocene species _E. Meridionales_
and _E. Antiquus_ still surviving, but in diminished numbers.
With these are found in vast abundance the remains of the
characteristic Elephant of the Post-Pliocene, the well-known
"Mammoth" (Elephas primigenius_), which is accompanied in North
America by the nearly-allied, but more southern species, the
_Elephas Americanus_. The Mammoth (fig. 266) is considerably
larger than the largest of the living Elephants, the skeleton
being over sixteen feet in length, exclusive of the tusks, and
over nine feet in height. The tusks are bent almost into a circle,
and are sometimes twelve feet in length, measured along their
curvature. In the frozen soil of Siberia several carcasses of
the Mammoth have been discovered with the flesh and skin still
attached to the bones, the most celebrated of these being a Mammoth
which was discovered at the beginning of this century at the
mouth of the Lena, on the borders of the Frozen Sea, and the
skeleton of which is now preserved at St Petersburg (fig. 266).
From the occurrence of the remains of the Mammoth in vast numbers
in Siberia, it might have been safely inferred that this ancient
Elephant was able to endure a far more rigorous climate than its
existing congeners. This inference has, however, been rendered
a certainty by the specimens just referred to, which show that
the Mammoth was protected against the cold by a thick coat of
reddish-brown wool, some nine or ten inches long, interspersed
with strong, coarse black hair more than a foot in length. The
teeth of the Mammoth (fig.267) are of the type of those of the
existing Indian Elephant, and are found in immense numbers in
certain localities. The Mammoth was essentially northern in its
distribution, never passing south of a line drawn through the
Pyrenees, the Alps, the northern shores of the Caspian, Lake
Baikal, Kamschatka, and the Stanovi Mountains (Dawkins). It occurs
in the Pre-Glacial forest-bed of Cromer in Norfolk, survived the
Glacial period, and is found abundantly in Post-Glacial deposits
in France, Germany, Britain, Russia in Europe, Asia, and North
America, being often associated with the Reindeer, Lemming, and
Musk-ox. That it survived into the earlier portion of the human
period is unquestionable, its remains having been found in a
great number of instances associated with implements of human
manufacture; whilst in one instance a recognisable portrait of
it has been discovered, carved on bone.
[Illustration: Fig. 267.--Molar tooth of the Mammoth (_Elephas
primigenius_), upper jaw, right side, one-third of the natural
size. a, Grinding surface; b, Side view. Post-Pliocene.]
Amongst other Elephants which occur in Post-Pliocene deposits
may be mentioned, as of special interest, the pigmy Elephants
of Malta. One of these--the _Elephas Melitensis_, or so-called
"Donkey-Elephant"--was not more than four and a half feet in
height. The other--the _Elephas Falconeri_, of Busk--was still
smaller, its average height at the withers not exceeding two
and a half to three feet.
[Illustration: Fig. 268.--Skull of _Ursus spelpeus_. Post-Pliocene,
Europe. One-sixth of the natural size.]
Whilst herbivorous animals abounded during the Post-Pliocene,
we have ample evidence of the coexistence with them of a number
of Carnivorous forms, both in the New and the Old World. The
Bears are represented in Europe by at least three species, two
of which--namely, the great Grizzly Bear (_Ursus ferox_) and
the smaller Brown Bear (_Ursus arctos_)--are in existence at the
present day. The third species is the celebrated Cave-bear (_Ursus
speloeus_, fig. 268), which is now extinct. The Cave-bear exceeded
in its dimensions the largest of modern Bears; and its remains,
as its name implies; have been found mainly in cavern-deposits.
Enormous numbers of this large and ferocious species must have
lived in Europe in Post-Glacial times; and that they survived
into the human period, is clearly shown by the common association
of their bones with the implements of man. They are occasionally
accompanied by the remains of a Glutton (the _Gulo speloeus_),
which does not appear to be really separable from the existing
Wolverine or Glutton of northern regions (the _Gulo luscus_).
In addition, we meet with the bones of the Wolf, Fox, Weasel,
Otter, Badger, Wild Cat, Panther, Hyæna, and Lion, &c., together
with the extinct _Machairodus_ or "Sabre-toothed Tiger." The
only two of these that deserve further mention are the Hyæna
and the Lion. The Cave-hyæna (_Hyoena speloea_, fig. 269) is
regarded by high authorities as nothing more than a variety of
the living Spotted Hyæna (_H. Crocuta_) of South Africa. This
well-known species inhabited Britain and a considerable portion
of Europe during a large part of the Post-Pliocene period; and
its remains often occur in great abundance. Indeed, some caves,
such as the Kirkdale Cavern in Yorkshire, were dens inhabited
during long periods by these animals, and thus contain the remains
of numerous individuals and of successive generations of Hyænas,
together with innumerable gnawed and bitten bones of their prey.
That the Cave-hyæna was a contemporary with Man in Western Europe
during Post-Glacial times is shown beyond a doubt by the common
association of its bones with human implements.
[Illustration: Fig. 269.--Skull of _Hyoena speloea_, one-fourth
of the natural size. Post-Phocene, Europe.]
Lastly, the so-called Cave-lion (_Felis speloea_), long supposed
to be a distinct species, has been shown to be nothing more than
a large variety of the existing Lion (_Felis leo_). This animal
inhabited Britain and Western Europe in times posterior to the
Glacial period, and was a contemporary of the Cave-hyæna, Cave-bear,
Woolly Rhinoceros, and Mammoth. The Cave-lion also unquestionably
survived into the earlier portion of the human period in Europe.
The Post-Pliocene deposits of Europe have further yielded the
remains of numerous _Rodents_--such as the Beaver, the Northern
Lemming, Marmots, Mice, Voles, Rabbits, &c.--together with the
gigantic extinct Beaver known as the _Trogontherium Cuvieri_
(fig. 270). The great _Castoroides Ohioensis_ of the Post-Pliocene
of North America is also a great extinct Beaver, which reached
a length of about five feet. Lastly, the Brazilian bone-caves
have yielded the remains of numerous Rodents of types now
characteristic of South America, such as Guinea-pigs, Capybaras,
tree-inhabiting Porcupines, and Coypus.
[Illustration: Fig. 270.--Lower jaw of _Trogontherium Cuvieri_,
one-fourth of the natural size. Post-Pliocene, Britain.]
The deposits just alluded to have further yielded the remains of
various Monkeys, such as Howling Monkeys, Squirrel Monkeys, and
Marmosets, all of which belong to the group of _Quadrumana_ which
is now exclusively confined to the South American continent--namely,
the "Platyrhine" Monkeys.
We still have very briefly to consider the occurrence of Man
in Post-Pliocene deposits; but before doing so, it will be well
to draw attention to the evidence afforded by the Post-Pliocene
Mammals as to the climate of Western Europe at this period. The
chief point which we have to notice is, that a considerable
revolution of opinion has taken place on this point. It was
originally believed that the presence of such animals as Elephants,
Lions, the Rhinoceros, and the Hippopotamus afforded an irrefragable
proof that the climate of Europe must have been a warm one, at any
rate during Post-Glacial times. The existence, also, of numbers
of Mammoths in Siberia, was further supposed to indicate that
this high temperature extended itself very far north. Upon the
whole, however, the evidence is against this view. Not only is
there great difficulty in supposing that the Arctic conditions of
the Glacial period were immediately followed by anything warmer
than a cold-temperate climate; but there is nothing in the nature
of the Mammals themselves which would absolutely forbid their
living in a temperate climate. The _Hippopotamus major_, though
probably clad in hair, offers some difficulty--since, as pointed
out by Professor Busk, it must have required a climate sufficiently
warm to insure that the rivers were not frozen over in the winter;
but it was probably a migratory animal, and its occurrence may
be accounted for by this. The Woolly Rhinoceros and the Mammoth
are known with certainty to have been protected with a thick
covering of wool and hair; and their extension northwards need
not necessarily have been limited by anything except the absence of
a sufficiently luxuriant vegetation to afford them food. The great
American Mastodon, though not certainly known to have possessed a
hairy covering, has been shown to have lived upon the shoots of
Spruce and Firs, trees characteristic of temperate regions--as
shown by the undigested food which has been found with its skeleton,
occupying the place of the stomach. The Lions and Hyænas, again,
as shown by Professor Boyd Dawkins, do not indicate necessarily
a warm climate. Wherever a sufficiency of herbivorous animals
to supply them with food can live, there they can live also;
and they have therefore no special bearing upon the question of
climate. After a review of the whole evidence, Professor Dawkins
concludes that the nearest approach at the present day to the
Post-Pliocene climate of Western Europe is to be found in the
climate of the great Siberian plains which stretch from the Altai
Mountains to the Frozen Sea. "Covered by impenetrable forests,
for the most part of Birch, Poplar, Larch, and Pines, and low
creeping dwarf Cedars, they present every gradation in climate
from the temperate to that in which the cold is too severe to admit
of the growth of trees, which decrease in size as the traveller
advances northwards, and are replaced by the grey mosses and
lichens that cover the low marshy 'tundras.' The maximum winter
cold, registered by Admiral Von Wrangel at Nishne Kolymsk, on
the banks of the Kolyma, is--65° in January. 'Then breathing
becomes difficult; the Reindeer, that citizen of the Polar region,
withdraws to the deepest thicket of the forest, and stands there
motionless as if deprived of life;' and trees burst asunder with
the cold. Throughout this area roam Elks, Black Bears, Foxes,
Sables, and Wolves, that afford subsistence to the Jakutian and
Tungusian fur-hunters. In the northern part countless herds of
Reindeer, Elks, Foxes, and Wolverines make up for the poverty
of vegetation by the rich abundance of animal life. 'Enormous
flights of Swans, Geese, and Ducks arrive in the spring, and seek
deserts where they may moult and build their nests in safety.
Ptarmigans run in troops amongst the bushes; little Snipes are
busy along the brooks and in the morasses; the social Crows seek
the neighbourhood of new habitations; and when the sun shines
in spring, one may even sometimes hear the cheerful note of the
Finch, and in autumn that of the Thrush.' Throughout this region
of woods, a hardy, middle-sized breed of horses lives under the
mastership and care of man, and is eminently adapted to bear the
severity of the climate.... The only limit to their northern
range is the difficulty of obtaining food. The severity of the
winter through the southern portion of this vast wooded area is
almost compensated for by the summer heat and its marvellous
effect on vegetation."--(Dawkins, 'Monograph of Pleistocene
Mammalia.')
Finally, a few words must be said as to the occurrence of the
remains of Man in Post-Pliocene deposits. That Man existed in
Western Europe and in Britain during the Post-Pliocene period, is
placed beyond a doubt by the occurrence of his bones in deposits
of this age, along with the much more frequent occurrence of
implements of human manufacture. At what precise point of time
during the Post-Pliocene period he first made his appearance is
still a matter of conjecture. Recent researches would render
it probable that the early inhabitants of Britain and Western
Europe were witnesses of the stupendous phenomena of the Glacial
period; but this cannot be said to have been demonstrated. That
Man existed in these regions during the Post-Glacial division
of Post-Pliocene time cannot be doubted for a moment. As to the
physical peculiarities of the ancient races that lived with the
Mammoth and the Woolly Rhinoceros, little is known compared with
what we may some day hope to know. Such information as we have,
however, based principally on the skulls of the Engis, Neanderthal,
Cro-Magnon, and Bruniquel caverns, would lead to the conclusion that
Post-Pliocene Man was in no respect inferior in his organisation
to, or less highly developed than, many existing races. All the
known skulls of this period, with the single exception of the
Neanderthal cranium, are in all respects average and normal in
their characters; and even the Neanderthal skull possessed a
cubic capacity at least equal to that of some existing races.
The implements of Post-Pliocene Man are exclusively of stone or
bone; and the former are invariably of rude shape and _undressed_.
These "palæolithic" tools (Gr. _palaios_; ancient; _lithos_,
stone) point to a very early condition of the arts; since the
men of the earlier portion of the Recent period, though likewise
unacquainted with the metals, were in the habit of polishing
or dressing the stone implements which they fabricated.
It is impossible here to enter further into this subject; and
it would be useless to do so without entering as well into a
consideration of the human remains of the Recent period--a period
which lies outside the province of the present work. So far as
Post-Pliocene Man is concerned, the chief points which the
palæontological student has to remember have been elsewhere
summarised by the author as follows:--
1. Man unquestionably existed during the later portion of what
Sir Charles Lyell has termed the "Post-Pliocene" period. In other
words, Man's existence dates back to a time when several remarkable
Mammals, previously mentioned, had not yet become extinct; but he
does not date back to a time anterior to the present _Molluscan_
fauna.
2. The antiquity of the so-called Post-Pliocene period is a matter
which must be mainly settled by the evidence of Geology proper,
and need not be discussed here.
3. The extinct Mammals with which man coexisted in Western Europe are
mostly of large size, the most important being the Mammoth (_Elephas
primogenius_), the Woolly Rhinoceros (_Rhinoceros tichorhinus_),
the Cave-lion (_Felis speloea_), the Cave-hyæna(_Hyoena speloea),
and the Cave-bear (_Ursus speloeus_). We do not know the causes
which led to the extinction of these Mammals; but we know that
hardly any Mammalian species has become extinct during the historical
period.
4. The extinct Mammals with which man coexisted are referable in
many cases to species which presumably required a very different
climate to that now prevailing in Western Europe. How long a
period, however, has been consumed in the bringing about of the
climatic changes thus indicated, we have no means of calculating
with any approach to accuracy.
5. Some of the deposits in which the remains of man have been
found associated with the bones of extinct Mammals, are such as
to show incontestably that great changes in the physical geography
and surface-configuration of Western Europe have taken place
since the period of their accumulation. We have, however, no
means at present of judging of the lapse of time thus indicated
except by analogies and comparisons which may be disputed.
6. The human implements which are associated with the remains
of extinct Mammals, themselves bear evidence of an exceedingly
barbarous condition of the human species. Post-Pliocene or
"Palæolithic" Man was clearly unacquainted with the use of any
of the metals. Not only so, but the workmanship of these ancient
races was much inferior to that of the later tribes, who were also
ignorant of the metals, and who also used nothing but weapons
and tools of stone, bone, &c.
7. Lastly, it is only with the human remains of the Post-Pliocene
period that the palæontologist proper has to deal. When we enter
the "Recent" period, in which the remains of Man are associated
with those of _existing species of Mammals_, we pass out of the
region of pure palæontology into the domain of the Archæologist
and the Ethnologist.
LITERATURE.
The following are some of the principal works and memoirs to which
the student may refer for information as to the Post-Pliocene
deposits and the remains which they contain, as well as to the
primitive races of mankind:--
(1) 'Elements of Geology.' Lyell.
(2) 'Antiquity of Man.' Lyell.
(3) 'Palæontological Memoirs.' Falconer.
(4) 'The Great Ice-age.' James Geikie.
(5) 'Manual of Palæontology.' Owen.
(6) 'British Fossil Mammals and Birds.' Owen.
(7) 'Cave-Hunting.' Boyd Dawkins.
(8) 'Prehistoric Times.' Lubbock.
(9) 'Ancient Stone Implements.' Evans.
(10) 'Prehistoric Man.' Daniel Wilson.
(11) 'Prehistoric Races of the United States.' Foster.
(12) 'Manual of Geology.' Dana.
(13) 'Monograph of Pleistocene Mammalia' (Palæontographical
Society). Boyd Dawkins and Sanford.
(14) 'Monograph of the Post-Tertiary Entomostraca of Scotland, &c.,
with an Introduction on the Post-Tertiary Deposits of Scotland'
(Ibid.) G. S. Brady, H. W. Crosskey, and D. Robertson.
(15) "Reports on Kent's Cavern"--'British Association Reports.'
Pengelly.
(16) "Reports on the Victoria Cavern, Settle"--'British Association
Reports.' Tiddeman.
(17) 'Ossemens Fossiles.' Cuvier.
(18) 'Reliquiæ Diluvianæ.' Buckland.
(19) "Fossil Mammalia"--'Zoology of the Voyage of the Beagle.'
Owen.
(20) 'Description of the Tooth and Part of the Skeleton of the
_Glyptodon_.' Owen.
(21) "Memoir on the Extinct Sloth Tribe of North
America"--'Smithsonian Contributions to Knowledge.' Leidy.
(22) "Report on Extinct Mammals of Australia"--'British Association,'
1844. Owen.
(23) 'Description of the Skeleton of an Extinct Gigantic Sloth
(_Mylodon robtutus_).' Owen.
(24) "Affinities and Probable Habits of Thylacoleo"--'Quart. Journ.
Geol. Soc.,' vol. xxiv. Flower.
(25) 'Prodromus of the Palæontology of Victoria.' M'Coy.
(26) 'Les Ossemens Fossiles des Cavernes de Liège.' Schmerling.
(27) 'Die Fauna der Pfahlbauten in der Schweiz.' Rütimeyer.
(28) "Extinct and Existing Bovine Animals of Scandinavia"--'Annals
of Natural History,' ser. 2, vol. iv., 1849. Nilsson.
(29) 'Man's Place in Nature.' Huxley.
(30) 'Les Temps Antéhistoriques en Belgique.' Dupont.
(31) "Classification of the Pleistocene Strata of Britain and the
Continent"--'Quart. Journ. Geol. Soc.,' vol. xxviii. Boyd Dawkins.
(32) 'Distribution of the Post-Glacial Mammalia' (Ibid.), vol. xxv.
Boyd Dawkins.
(33) 'On British Fossil Oxen' (Ibid.), vols. xxii. and xxiii. Boyd
Dawkins.
(34) 'British Prehistoric Mammals' (Congress of Prehistoric
Archæology, 1868). Boyd Dawkins.
(35) 'Reliquiæ Aquitanicæ.' Lartet and Christy.
(36) 'Zoologie et Paléontologie Françaises.' Gervais.
(37) 'Notes on the Post-Pliocene Geology of Canada.' Dawson.
(38) "On the Connection between the existing Fauna and Flora of
Great Britain and certain Geological Changes"--'Mem. Geol.
Survey.' Edward Forbes.
(39) 'Cavern-Researches.' M'Enery. Edited by Vivian.
(40) "Quaternary Gravels"--'Quart. Journ. Geol. Soc.,' vol. xxv.
Tylor.