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191

THE SURFACE OF THE GLOBE

It is only a little above, in the coppery bituminous
slates, that we discover the first traces of them; and,
what is very remarkable, the first quadrupeds are
reptiles of the lizard tribe, very much like the large
monitors now existing in the torrid zone. Several
individuals of this species are found in the mines of
Thuringia,(1) in the midst of innumerable fishes of
genera now unknown; but which, in their
correspondence with the genera of the present times,
appear to have lived in fresh water.
We know that the monitors are also fresh-water
animals. A little higher is the limestone called Alpine,
and above it the shelly limestone, so rich in entrochites
and encrinites, which forms the basis of a great part of
Germany and Lorraine.
It has produced skeletons of a large sea tortoise,
whose shells might be from six to eight feet in length;
and those of another oviparous quadruped of the lizard
tribe, of great size, and with a sharp pointed nose.(2)
Ascending through the sandstones, which only offer
vegetable imprints of large arundinaceæ, bamboos,
palms, and other monocotyledonous plants, we reach
the different layers of the limestone called limestone
of Jura, because it forms the principal nucleus of this
chain.
Herein the class of reptiles developes itself fully,
and manifests itself in various forms, and of gigantic
size.
The middle part, composed of oolites and lias, or of
gray limestone with grypheæ, has had in deposite the
remains of two genera the most extraordinary of all,
which have united the characters of the

(1) See my 'Recherches sur les Ossemens Fossiles,' v. 5, 2nd part, p.
300.
(2) 'Recherches,' vol. 5, 2nd part, pp. 355 and 525.


192

ON THE REVOLUTIONS OF

class of oviparous quadrupeds with the organs of
motion similar to those of the cetacea.
The ichthyosaurus,(1) discovered by Sir Everard
Home, has the head of a lizard, but extended into a
pointed muzzle, armed with conical and pointed teeth;
enormous eyes, of which the sclerotica is strengthened.
with a bony case; a spine composed of flattened
vertebræ, like the pieces used at the game of draughts,
and concave on both sides like those of fishes; the ribs
slender, the sternum and shoulder-bones like those of
lizards and ornithorynchi; the pelvis small and weak;
and four limbs, of which the humeri and femora are
short and thick, and the other bones flatter, and set
near each other like the stones of a pavement, so as to
compose, when enveloped in skin, fins all in a piece
and scarcely able to be bent; in a word, analogous,
both in its use and construction, to those of cetacea.
These reptiles lived in the sea; on land they could at
best only crawl along like seals; and at the same time
they breathed elastic air.
The remains of four species have been discovered.
That most extensively found (I. communis) has blunt
conical teeth, and is sometimes twenty feet long.
The second (I. platyodon) at least as large, has
compressed teeth, with round and swelling roots.
The third (I. tenuirostris) has slender and pointed
teeth, and the muzzle slim and lengthened.
The fourth (I. intermedius) has teeth of a medium
nature between the last species and the first. The two
latter species do not attain half the size of the two
former.(2)

(1) See Recherches, vol. 5, 2nd part, pp. 4 and 7.
(2) Ib. v. 5, 2nd part, p. 456.


193

THE SURFACE OF THE GLOBE

The plesiosaurus,discovered by Mr. Conybeare,
must have appeared even more monstrous than the
ichthyosaurus. It had similar limbs, but rather more
elongated and flexible; its shoulder and pelvis were
stronger, its vertebrae were nearly assimilated to those
of lizards, but what distinguished it from all oviparous
and viviparous quadrupeds, was a slender neck as long
as its body, composed of thirty vertebræ and upwards,
a number greater than that of the neck of all other
animals, rising from the trunk like the body of a
serpent, and terminated by a very small head, in which
are to be found all essential characteristics of those of
lizards.
If any thing could justify those hydras and other
monsters which are so often drawn on the monuments
of the middle ages, it would assuredly be this
plesiosaurus. (1)
Five species are already known, the most generally
distributed (P. dolichodeirus) is more than twenty feet
long.
A second (P. recentior) found in recent strata, has
flatter vertebræ.
A third (P. carinatus) has a prominence on the
lower surface of the vertebræ.
A fourth, and lastly a fifth (P. pentagonus) and (P.
trigonus) have respectively five and three
prominences.(2)
These two genera are every where distributed in the
lias. They were discovered in England, where the lias
is exposed in cliffs of great extent, and they have been
also found in France and Germany.
With them there existed two species of crocodiles,
whose bones are also deposited in the lias,

(1) See Recherches, v.5, 2nd part, pp. 475, et seq.
(2) Ib. v. 5, 2nd part, pp. 485 and 486


194

ON THE REVOLUTIONS OF

amongst ammonites, terebratulæ, and other shells of
this ancient sea. We have skeletons of them in our
cliffs at Honfleur, where are found the remains from
which I have drawn their characters. (1)
One of the species, the long-nosed gavial, has a
muzzle longer and the head sharper than the gavial, or
long-nosed crocodile of the Ganges; the body of its
vertebræ is convex in front, whilst in the crocodiles
now existing they are so behind. It has been found in
the lias of Franconia as wel as in those of France.
A second species, the short-nosed gavial, with a
muzzle of middling length, less pointing than that of
the gavial of the Ganges, and more so than the
crocodiles as now seen in San Domingo. The vertebræ
were slightly hollowed at the two extremities.
But these crocodiles are not the only animals which
have been found in these beds of secondary limestone.
The fine oolite quarries of Caen have produced a
very remarkable one, of which the muzzle, as long and
as pointed as the long-nosed gavial, has a head wider
behind, with the fossæ of the temporal bones larger. It
was by reason of its stony scales, with round cavities,
the best armed of all the crocodiles. (2) The teeth of
the lower jaw are alternately longer and shorter.
There is another species in the oolites of England,
but it is only known by some parts of its cranium,
which is not sufficient to afford a perfect idea of it.(3)

(1) See Recherches, v. 5, 2nd part, p. 143.
(2) Ib. vol. v. 2nd part, p. 127.
(3) We expect a full explanation of it from the researches of Mr.
Conybeare.


195

THE SURFACE OF THE GLOBE

Another very remarkable genus of reptiles, whose
remains, although also found in the concretion of lias,
abound particularly in the oolite and the higher sands,
is the megalosaurus, properly so called; for, with the
shape of lizards, and particularly of the monitors, of
which it has also the cutting and indented teeth, it was
of so enormous a size, that in assigning to it the
properties of the monitors it would exceed seventy feet
in length. It would be a lizard as large as a whale. (1)
It was discovered in England by Mr. Buckland, but we
have them also in France, and some of its bones have
been found in Germany, if not of the same species, at
least of a species which cannot be classed with any
other genus. We are indebted to M. de Sœmmering for
the first description of it. He discovered the remains in
the superior strata of the oolites, in the calcareous
schists (slates) of Franconia, long celebrated for the
numerous fossils with which they have supplied the
cabinets of the curious, and which will be made still
more useful by the services which their peculiar
adaptation for the purposes of lithography will enable
them to render to the arts and sciences.
Crocodiles also are found in these limestone schists,
and always those with the long muzzle. M. de
Soemmerring has described one (the C. priscus)of
which the entire skeleton of a small individual was
preserved almost as well as it could have been in our
cabinets. (2) It is one of those which resemble the real
gavial of the Garrges; but the united portion of its
lower jaw is not so long; the lower teeth are
alternately and regularly longer

(1) See Recherches, vol. ii. 2nd part, p. 343.
(2) Ibid. vol. v. 2nd part, p. 120.


196

ON THE REVOLUTIONS OF

and shorter, and it has ten additional vertebra at the
tail.
But the most remarkable animals which are
deposited in these limestone schists, are the flying
lizards, which I have named pterodactyli.
They are reptiles with a very short tail, a very long
back, a muzzle greatly extended and armed with sharp
teeth, supported on high legs, the anterior extremity
has an excessively elongated claw, which probably
supported a membrane which sustained it in the air,
together with four other toes of ordinary size
terminated by hooked claws. One of these strange
animals, whose appearance would be frightful, was
about the size of a thrush,(1) and the other that of a
common bat;(2) but from fragments we find that there
existed a much larger species. (3)
A little above these calcareous schists is the
limestone (nearly homogenous) of the ridge of Jura. It
contains also bones, but always those of reptiles;
crocodiles and fresh-water tortoises, of which it
produces an abundance in the environs of Soleure.
They have been there discovered and scrutinized with
much care by M. Hugi; and from the fragments already
collected we can easily recognise a considerable
number of the species of the fresh water tortoise, or
emydes, which ulterior discoveries only can determine,
but many of which have been already distinguished by
their sizes and shapes from all kinds of known emydes.
(4)
It is among these numerous oviparous quadrupeds of
all sizes and forms; in the midst of these

(1) Ibid. pp. 358, et seq. (2) Ibid. p. 376.
(3) Ibid. p. 380.
(4) Ibid. vol. v. 2nd part, p. 225.


197

THE SURFACE OF THE GLOBE

crocodiles, of these tortoises, of these flying reptiles,
of these immense megalosauri of these monstrous
plesiosauri, that some small mammifera are said to be
first detected. It is certain that jaw bones, and some
bones discovered in England belong to this class, and
particularly to the family of dideiphides, or those of
insectivorous animals.
It may, however, be suspected that the stones which
incrust them have originated from some local
recomposition subsequent to the epoch of the
formation of these layers. However that may be, we
find still that the reptile tribe predominated
exclusively for a long time.
The ferruginous sands placed in England above the
chalk, abound with crocodiles, tortoises, megalosauri,
and particularly with a reptile which presents the
singular character of using his teeth like our
herbivorous mammifera.
Mr. Mantell, of Lewes, in Sussex, discovered this
peculiar animal, as well as other large reptiles, in the
sands beneath the chalk. He named it the iquanodon.
(1)
In the chalk itself there are only reptilia, we find
remains of tortoises and crocodiles. The famous soft
sandstone quarries (carrières de tuffau)of the mountain
of St. Peter, near Maestricht, which belong to the
formation of chalk, have given beside the very large
sea tortoises and a vast quantity of shells and marine
zoophytes, a genus of lizards, not less gigantic than the
megalosauri, which has become famous from the
researches of Camper, and by the figures which Faujus
has given of its bones in his history of this mountain.
It was upwards of twenty-five feet long; its great
jaws were armed with very strong teeth, conical.

(1) See Recherches, pp. 161, 132 and 350.


198

ON THE REVOLUTIONS OF

rather arched and ridged, and it had also some of these
teeth in the palate. There were more than a hundred
and thirty vertebræ in its spine, convex in front and
concave behind. — Its tail was high and broad, and
formed a large vertical oar. (1) Mr. Conybeare has
recently proposed to call it the mosasaurus.
The clays and lignites, which are above the chalk,
have only produced crocodiles;(2) and I have every
reason to conclude that the lignites in Switzerland, in
which have been found the bones of the beaver and
mastodon, belong to a more recent period. It is only in
the coarse limestone which rests on these clays that I
have first found the bones of mammifera; and even
these belong to marine mammifera, to unknown
dolphins, to lamantins and morses.
Amongst the dolphins, there is one whose muzzle,
more lengthened than in any known species, had the
lower jaw united to an extent nearly equal to that of a
gavial. It was found near Dax, by the late President of
Borda. (3)
Another of the rocks in the department of Orne, has
also a long muzzle, but rather differently shaped. (4)
The whole genus of lamantins is now marine, and
inhabit the seas of the torrid zone; and that of the
morses, of whom we have but one living spe ies, is
confined to the icy sea. However, we find the skeleton
of these two species together in the layers of the coarse
limestone of the middle of France; and this union of
species, of which the most similar are now in opposite
zones, will again occur in our researches more than
once.

(1) See Recherches, vol. v. 2nd part, pp. 310, et seq.
(2) Ibid. p. 163.
(3) Ibid. 1st part, p316. (4) Ibid. p. 317.


199

THE SURFACE OF THE GLOBE

Our fossil lamantins differ from the known lamantins,
by having a head more elongated, and otherwise
constructed. (1) Their ribs easily recognised by their
rounded thickness and by the density of their texture,
are not rare in our different provinces.
As to the fossil morse we have as yet only fragments
insufficient to characterise the species. (2)
It is only in the layers which have succeeded the
coarse limestone, or at most in those which might have
been formed at the same time with it, but deposited in
the fresh water lakes, that the class of land mammifera
begins to show itself in any abundance.
I regard as belonging to the same age, and as having
lived at the same time, but perhaps in different
situations, those animals whose remains are buried in
the molasse, and the ancient beds of gravel in the south
of France; in the gypsum layers mingled with
limestone, similar to those in the environs of Paris and
Aix, and in the marly deposites of fresh water, covered
by the marine beds of Alsace, the province of Orleans,
and of Bern.
This animal population has a very remarkable
character in the abundance and variety of certain
genera of pachydermata,which are unknown amongst
the quadrupeds now existing, and the characteristics of
which are more or less nearly related to tapirs,
rhinoceroses, and camels.
The genera whose discovery is entirely due to me
are: the palæotheria, the lophiodonta, the
anoplotheria, the anthracotheria, the cheropotami, and
the adapis.

(1) See Recherches, p, 266.
(2) Ibid. p. 521.


200

ON THE REVOLUTIONS OF

The palæotheria resemble the tapirs in the general
form, in that of the head, and particularly in the
shortness of the bones of the nose, which proves that
they had, like the tapirs, a small proboscis; and also in
having six incisores and two canine teeth in each jaw;
but they resembled the rhinoceros in their grinders, of
which the upper ones were square, with prominent
ridges differently shaped, and the lower ones shaped
like double crescents, and their feet in like manner
were divided into three toes, while the fore feet of the
tapir have four divisions.
It is one of the genera the most distributed and
numerous in species, that are found in the layers of its
particular period. Our gypsum quarries in the environs
of Paris are crowded with them. The first, (P.
magnum) as large as a horse. Three resemble swine,
but one (P. medium) has narrow and long feet; one (P.
crassum) with larger feet; one (P. latum) with feet still
larger and much more short; the fifth species (P.
curtum) of the size of a sheep, is much lower, and has
feet still larger and shorter in proportion than the last;
a sixth, (P. minus) is of the size of a small sheep, and
has slim feet, the lateral toes of which are shorter than
the others; and finally, there is one (P. minimum) not
larger than a hare, which hasalso long and slender
feet.(1)
They have also been found in other provinces of
France; at Puy in Velay, in the beds of gypseous marl,
one species (P. velaunum,) (2) very similar to the (P.
medium,) but differing from it in the formation of the
lower jaw; in the vicinity of Orleans, in the layer of
marly stone, a species

(1) See Recherches, v. iii. and particularly p. 250, and v. 5, 2nd part, p.
505.
(2) Ibid.

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