Arthur Nicols.

The puzzle of life, and how it has been put together : a short history of the formation of the earth, with its vegetable and animal life, from the earliest times, including an account of Pre-historic man, his Weapons, Tools, and Works online

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Online LibraryArthur NicolsThe puzzle of life, and how it has been put together : a short history of the formation of the earth, with its vegetable and animal life, from the earliest times, including an account of Pre-historic man, his Weapons, Tools, and Works → online text (page 4 of 8)
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which is scarcely wood and scarcely coal, of a
brown colour. In fact, lignite is wood almost
turned to coal, and it has helped us to learn
that coal was once living wood ; but it is not
nearly so old as the coal. Then again there
is the beautiful substance called "jet" used for
making bracelets. This is a kind of fossil
gum or pitch dropped from the trees while
they were growing, and, though different in
colour, it is much the same in kind as amber.
Amber is often found with flies, spiders, and
small leaves imbedded in it. When this fossil
resin or gum was flowing out of the ancient
pine-trees, and was quite sticky, flies settled
upon it and became entangled in it, and as
more of the gum flowed out they became
quite covered. Then the gum dropped from
the tree and hardened, and it is now found in
lumps on the shores of the Baltic Sea, and in
beds of sand and clay with fossil wood. It is
of a beautiful bright yellow colour, and beads
for necklaces and other ornaments are made
out of it.

If we arrange the things we have been
talking about in order, the oldest first, they


would come thus : plumbago or black-lead
or, as I have called it, eodendron, " the life-
dawn plant "-first, then hard coal, then soft
coal, then lignite and jet, then bog oak and
peat. But I must tell you something about
bog oak and peat. In many of the swamps
and bogs of the World the trunks of dead
trees are found, which have become quite
black and almost like lignite, because they
have been buried so long. Thus, in the bogs
of Ireland oak trees are often found, and they
were most likely living when the reindeer in-
habited Ireland. This old bogwood is made
into beads for necklaces and other ornaments.
Peat is a partly decayed vegetable substance,
with beautiful little plants growing on its sur-
face, and is really coal in its infancy. It is found
all over the world more or less in wet places,
and consists of the roots and stems of mosses
and reeds, some of which are like the gigantic
plants of the coal period, but very small in
comparison. I have no doubt that in time
some of these peat bogs may be turned into
coal if they sink down and become covered
with other earths, but at present they are all


on the surface and so soft that they are dan-
gerous to walk upon because one may sink
in and be smothered.

This, as far as we can trace it, is a sketch
of the history of vegetable life on our Earth.
We will go back to the coal for a moment and
see what the animal life of that time was.
The seas of the time of the coal forests were
sometimes shallow, sometimes deep, and in
the limestone rocks of the oceans which
separated the great continents of that time
there is a record of the inhabitants of the
seas. The land plants were of more than
1,000 different kinds, and there were more
than 200 kinds of fishes in the waters, and
corals, shells, and small crab-like animals in-
numerable. The fishes were fellows with
terrible teeth, and their bodies were covered
with strong hard scales. One of these fish
was thirty feet long, and there were others
of considerable size. It is curious that the
fishes of this time remind one of reptiles
(lizards and crocodiles), just as the birds of
a future time seem to have something of the
reptile about them, as you will see by-and-by.


I dare say you have remarked while
reading that all the plants and animals of the
early ages of the world seem to be made on
a simple plan, and as the Earth grows older
they become more perfect, and this is just
what I want you to take notice of all through.
The plants of the coal period, you have seen,
were nothing like so perfect in construction,
beautiful as they were, as the forest trees of
the present time, neither were the animals
so perfect as those living now. There has
been progress, step by step, throughout the
vegetable and animal creation ; and, though
many of the lower forms of the early ages
exist now, there are others far superior to
them which did not exist then : but all this
will come in "The Animal Part."

About the middle of the Earth's age came
the wonderful period of vegetation which
gave us our coal, and after that there was a
great and busy time, when huge reptiles and
reptile-like birds, and then true birds, made
their appearance. But that belongs to the
next part of the "puzzle of life."

If we look with astonishment at the coal


forests, we may also well think of them with
thankfulness. Here is the sunshine of past
ages stored up for our use, and we bring it
out again to warm ourselves, cook our food,
make all our iron things, and drive our steam-
engines ! Can any romance be finer than
this, that we are carried across to America
and India and Australia in steam-boats driven
by the "fossil sunlight" of ages and ages past,
and whirled along at sixty miles an hour over
iron rails by the same stored-up strength ?

If you doubt this, think of living trees. Do
they not live by the air and sunlight ? Will
they grow without these ? They spread
their branches and leaves to gather the
warmth and light from the air, and when
they are cut down and dried, and you put a
match to the wood, all the old warmth and
light come out again ; and we know that
the coal is only fossil wood. Our Creator
wastes nothing. Even when there were no
people living to rejoice in the sun, He
thought of those people who should come in
time, and not one of the fiery rays of the
fierce sun was lost. These mighty forests


were sent to gather it, and when they had
died down they sank below the surface and
were covered from the air, that none of their
light or heat should escape.

In such forests it is strange that there
were no birds, especially as there were swarms
of insects, and no doubt abundance of worms.
But no bone of bird or any trace of feathered
songster of these lovely groves has yet been
found. Little lizards chased flies and beetles
up and down the stems of the club-mosses and
ferns, and larger reptiles lurked in the long
damp grass under the shade. The pools and
ponds were filled with curious fishes, and
reefs of beautiful white coral fringed all the
shores of the seas.

But the Earth was not fit for the habitation
of man. The fruits of the trees were not such
as he could have eaten, and their wood was
not hard enough to build houses of. Still it
was being got ready for him, and not a leaf
waved uselessly in the bright, warm air, and
not a tree fell to the ground, but it was to be
turned into coal, and to come forth again one
day a hard black lump, without any of its
former beauty, but to give back the light and


heat it had gathered from the sun ages and
ages ago.

Many periods in the Earth's history have
passed since the coal period, and in every
one of these the trees have been increasing
in perfection, though there have never since
been such great numbers of a few kinds
growing. When we come to the more lately
formed beds of earth we begin to find the
cypress, willow, ash, oak, elm, and other
forest trees which are living now. The
trunks of these trees, blackened by age, lie
buried in peat bogs and swamps all over
Europe. The mighty Mississippi river brings
down immense quantities of dead trees, and
as these sink to the bottom near its mouth
they are forming future coal beds. Along
the coast of Norfolk and Suffolk, too, and
stretching far away under the German
Ocean, is an old English forest. In some
places the trunks of the buried trees may
be seen standing upright just where they
grew. The nets of the fishermen are con-
tinually bringing up pieces of wood, roots,
and seeds ; and when the sea washes away
the soft cliffs here the bones, teeth, and tusks


of the elephant, rhinoceros, hippopotamus,
and other large animals which inhabited this
forest, may be seen in great numbers.

Down below the waves of ocean have
these woods sunk with all their once living
creatures, and though you may suppose that
it must have been very long ago that they
grew, they are of the same kind as those
which now make the hills and valleys of
England beautiful.

Sometimes a forest must sink very fast,
for travellers have told us how they have
sailed on rivers and lakes over the tops of
sunken trees, and, looking down into the
clear water, have seen the branches waving
below tall trees standing upright at the
bottom, and the boats sailing over their tops !

We must now pass on to the living crea-
tures which peopled the Earth, and their
story can be told with more certainty than
that of the perishable plants which clothed
the surface of the ground, and, while they
rendered it beautiful, also served as food and
shelter for innumerable animals, and have
become so useful to us as coal, lignite, black-
lead, and other productions of ancient forests.



WE must now go back and collect the
smaller pieces of "the puzzle" which make
up the animal part. The great periods of
vegetation ended in our country with the coal
forests, and there has been no such wonder-
ful growth of plants since the time when the
New Red Sandstone, lying above the coal,
was formed ; though no doubt trees and plants
have since flourished, as they do now on the
Earth, but not in such quantities as during
the coal period.

We remember that the eozoon, " the life-
dawn animal," is the oldest animal we know
of, and that it lived so long ago as when the
Laurentian rocks were laid down at the
bottom of the seas of that time ; then in
later rocks we find the burrows of sea worms
in the stone, and later still simple shells
with two valves like the common mussel, and


other animals of a simple kind, like the corals,
sponges, and star-fishes which exist now.
There must have been millions of these
creatures in the older limestone seas, for the
rocks are almost entirely composed of their
fossil shells and bodies. By-and-by a rather
superior animal inhabited the seas of Wales,
called a trilobite, of which you will see a
picture on the opposite page. This curious
animal was of the same family as the shrimps
and prawns, but much larger, and he must
have been a giant among the others. None
of these animals had any bones, you must
understand ; but they had a hard shelly
covering to support their soft bodies inside,
and no doubt the trilobites were able to swim
about very fast. 1

What I want you to take notice of now is
the progress that has been going on from the
almost motionless eozoon to the shell-fish
and star-fish, which could crawl along the
bottom of the sea and over the rocks, to this
active, quick-moving trilobite, with his great
paddles. Then the next step is a very great

1 Numerous specimens in Case No. 7, Room V.






one, when we come to animals with bones.
The first of these are fishes. All the other
bones are joined to the backbone, therefore
all animals with bones are called vertebrata,
which is a Latin word meaning having a
backbone with joints. Now animals with
bones are plainly superior to those with only
shells, and when we find fishes among the
rocks of Wales and Devonshire we know
that we are beginning to pick up some
important pieces of the "puzzle of life."
These fishes were most of them related to
the sturgeon, and their bones and teeth are
found in great quantities in the Old Red
Sandstone rocks, just below the coal. 1

It is not until we get above the coal into
the oolite or egg-stone rocks that still larger
and altogether superior animals, both of sea
and land, began to increase, and this is called


This has been called the reptile age be-
cause there were such numbers of animals

1 Specimens of fossil fishes from various rocks in Wall-
case No. I, Room II.



like crocodiles, lizards, and tortoises (which
are all reptiles), and some of them were of
immense size. For instance, there was a huge
creature something like a frog, but as large
as a Shetland pony, called the Labyrinthodon,
with a great many curious teeth, and this
animal has left footprints in the New Red
Sandstone which have been dried and buried,
we can't tell how long, and there are the
cracks made by the sun drying the place he
walked over when that was soft earth.
There is a drawing of some of these footsteps
in the picture on the next page, and there
are also the footprints of a large bird, and
you can see where he walked over the soft
earth and made a long line of footmarks ; and
if you look at the footprints of birds on the
snow or mud now you will notice marks just
like these. Then there is another picture of
a single footprint of a large bird, and all those
round dots are where rain drops fell and left
their marks in the soft earth.

I dare say you will wonder how it is that
these footprints have not disappeared. Well,
when the animals and birds that made them


Footprints of Labyrinthodon.

Footprints of Birds, (2) with marks of Rain-drops.
G 2


had gone the marks became filled with dry
sand, no doubt blown in by the wind, and
then the mud dried hard, and at last it became
covered with other earths and sank slowly
down, just as the coal forests had done before,
and remained there until we dug it up with
these tracks of the birds and animals that
lived then. Some of these birds must have
been larger than any living now, because their
footmarks are so long. None of their bones
have been found yet, I believe, but plenty of
the teeth and some bones of the labyrin-
thodon have. The real footmarks, of course,
are very large, though they are small in the
picture. 1

In the great beds of Lias there are many
other strange animals, and among them are
two great fish-lizards called the Ichthyosaurus
and Plesiosaiirus. Both of these lived in the
water and perhaps came on land sometimes,
and it is certain that they must have been very
ferocious creatures, from their great size and
sharp teeth. The plesiosaurus would be able

1 See examples in the large Wall-cases in Rooms I., II.,
and III., North Gallery.


to raise his long neck above the water and
snap at some of those curious birds rather
like bats which lived at the time, and of
which I shall have something to say presently.
Some of these fish-lizards were as large as
whales, and their bodies have been so beauti-
fully preserved in the limestone rocks that we
can actually sometimes find in their stomachs
the food they lived on.

Now we have got to a higher order of
creation still, these fish-lizards, and they re-
mind one of the next step in progress birds.
You know that all birds lay eggs, so do
almost all reptiles, such as crocodiles, lizards,
and most snakes, so that they are alike in
this. Then the plesiosaurus with his long
neck reminds us of such birds as the heron
and the swan, but he is altogether more like
a reptile than either a fish or a bird. There
were also huge land reptiles, which lived in
the forests of the time, and must have been a
terror to the smaller animals. From the bones
of one of these which have been found in the
oolite clays near Weymouth in Dorsetshire
(the Cetiosaurus)> we see that it must have



been nearly as large as an elephant, and
there are others called the Megalosaurus,
Dinosaurus, &c. All these names end with
sauriis, a name taken from the Greek word
meaning lizard ; and you will see now why the
oolite, or "Jurassic" 1 age, as it is sometimes
called, is well named the " reptile age," for
these creatures swarmed on the land and in
the sea. Specimens of these you can see for
yourselves in the cases on the walls of the
third room in the North Gallery of the British
Museum, where all the fossils are collected.

But still more extraordinary animals
than any of these lived at the time, and we
can scarcely tell whether they were birds or
reptiles, as they were something like both,
but I suppose we must call them flying rep-
tiles, and they are the nearest approach to
birds that had yet existed. These creatures
are called Pterodactyles, from two Greek words
which mean "wing-fingered." Suppose the
little fingers of both your hands were a yard
longer than the others, and suppose a thick

1 So called because the mountain chain of the Jura Alps
was raised during this period.


leathery skin was stretched from the tips of
your long little fingers to each of your feet,
you would have wings something like a
pterodactyl and also something like the
wings of a bat. But the pterodactyl had a
long neck and a long beak-like mouth, full
of long sharp pointed teeth. It could not
walk much I think, but it could hang itself
up by its hind limbs to a tree or rock, head
downwards like a bat, and must have been
able to fly very strongly, with its huge
leathery wings, but it had no feathers.
There were swarms of these curious half
lizard half bird-like animals on the land, and
they were of all sizes, some no bigger than
a crow, and some as large as the albatross,
measuring twelve feet across their out-
stretched wings. Their skeletons are some
of the commonest fossils in the oolite rocks,
all through the great reptile age. 1

Now you see we have come to a reptile
that can fly, but, excepting for its wings and
some of its bones, more like a crocodile than

1 Several specimens in Room III., and in Table-case
No. 1 6, Room IV.


a bird. A little further on we find another
curious animal in the oolite rocks, which is
much more like a true bird than the ptero-
dactyl, because it had feathered wings. It is
called the Archceopteryx, which means "an-
cient wing," and I have given a picture of it
on the same page as the pterodactyl, so that
you may compare them together. The blade-
bone and " merry-thought " of this creature
were exactly like those of a bird, and so
were the feet and legs, which would enable
it to walk easily, or perch on the branch of
a tree, but the tail was long and many-
jointed like that of a lizard, with a fan of
feathers growing on each side of it, and
short feathered wings. Then it most likely
had teeth like a lizard, and there were short
claws at the bend of the wings. This bird-
reptile was about the size of a crow, and was
the first we know of with feathers, and the
limestone rock has preserved it most beauti-
fully through all the long ages which have
passed since it flitted over the land of the
oolite period. 1 Later still than these, there

1 Wall-case No. n in Room III., several specimens,


lived in America, about the time the chalk was
formed in England, two strange birds called
Hesperornis and Ichthyornis, both of which
had teeth in the jaws. The former was an
immense fellow like the penguin, with short
wings, and the latter was about the size of a
pigeon with large feathered wings.

They are finding more of these curious
creatures every now and then in America.
Some are without teeth, and have a horny
bill like that of a real bird, and in other ways
more nearly resemble living birds ; still they
have not lost the appearance of reptiles in
their principal bones.

I have been particular in describing some
of these fish-lizards and bird- reptiles ; because
they, or their near relations, were the princi-
pal inhabitants of land and sea from the end
of the coal period to the end of the chalk,
though there were of course swarms of fishes
and shell-fish ; but I ought to tell you that
even so early as this there was at least one
animal known which suckled its young ones,
and this was a small insect- eating creature
not larger than a rat, of the same family


Pterodactyl ( Wing-finger).

Archaopteryx (Ancient-wing).


(called Marsupial] as the kangaroo of
Australia, which carries its young ones in
a pocket or pouch in its skin.

All this time we have been hunting for
parts of " the puzzle " in those ancient oolite
rocks between the coal and the chalk, and
those we have found are very important.
We have seen the slow progress from simple
sea shells to simple fishes, and then onwards
to fish-lizards and bird-reptiles with one
little marsupial animal, of a far higher kind,
in between, as if to tell us beforehand what
more complete and perfect animals we might
expect by-and-by. After the fishes we have
found fish-lizards, then bird-reptiles with
wings, but no feathers, and later still a bird-
reptile with wing and tail feathers. How
different the life of the Earth was at the end
of the " reptile age " of the oolite rocks, to
the far back Laurentian time when one
little creature, our old friend eozoon, alone
held possession of the seas !


Now let us look into the rocks next
above, and see what is to be found there.


We have arrived in the Cretaceous period,
or time when the chalk was formed. 1 You
remember I told you you might call this
" foraminifera earth " because so much of
it was made up of the shells of these tiny
animals, thousands of which could be put into
a thimble. Whenever you make a mark with
a piece of drawing chalk you rub off a number
of them, and you will see what pretty little
creatures they were if you look at the drawings
of some of them on the next page as they are
seen under the microscope, magnified thou-
sands of times their natural size ; but there
are others of different shapes. On the same
page too there is a handsome shell, called an
ammonite, and of its real size, common in
chalk rocks. The seas of the time must have
been very deep as I have explained before,
and the chalk contains numbers of bones of
fishes everywhere, and many of the remains
of the reptile-like creatures of the time before.
Corals, sea-urchins, crabs, &c., abounded, and
as you can scarcely ever see chalk without
immense flint stones in it, you may suppose

1 From the Latin word " creta," meaning chalk.





i Ammonite. 234 Foraminifera (Chalk-builders).



what millions of sponges lived on the rocks,
for these flints are partly made up of their
fossil bodies. 1 Another Cretaceous period is
beginning now at the bottom of the Atlantic
and Pacific Oceans, where it is deep enough
to cover the Alps, for these little foraminifera
are living on the surface in countless millions,
and day by day their fossil shells are settling
down to the bottom and forming a soft grey
mud, full of the carbonate of lime like chalk.
The climate of the Cretaceous age was mild
and pleasant, as we know from the kind of
animals in the seas. Slowly the water began
to get shallower and shallower by the up-
heaval of the bed, and at last the bottom of
this mighty chalk ocean came up to the light
and sun, to be covered in some places with the
drift and worn particles of older rocks swept
over it by rivers, and to receive new plants and
new animals, and in some places to remain
almost bare, as it is on the downs of Brighton.
Now we take one more step upwards into

1 Ammonites in the Table-cases in Rooms V. and VI.
For enlarged models of foraminifera, see Case No. 15 in
Room V.

H 2


almost a new world the world on which
mighty animals lived, and which man came
to share with them.


The reign of the reptiles is now passed.
The ichthyosaurus and pterodactyl no longer
inhabited the seas and continents. Great
changes had taken place in the shape of the
land. A river larger than the Rhine swept
majestically through England from the bor-
ders of Wales right out into the German
Ocean, and its banks were covered with forests
and marshes, where the new animals which
had come to take possession of the earth
lived and moved and had their being. The
mountains of the Pyrenees were raised above
the sea, and parts of Surrey and Sussex
appeared too. It was most likely in the
early part of the Tertiary period that the
stone was formed of which almost all Paris
is built. Fancy a great city built of the shells
of dead animals ! One can scarcely believe it-:
but the microscope lets us into this secret of
Nature. If we take a piece of this stone and

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Online LibraryArthur NicolsThe puzzle of life, and how it has been put together : a short history of the formation of the earth, with its vegetable and animal life, from the earliest times, including an account of Pre-historic man, his Weapons, Tools, and Works → online text (page 4 of 8)