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pouncing on the unfortunate reptile by the neck and bearing it off in the air. The
: anecdote told by Humboldt of a native of Calabozo being awakened in the middle
of the night by one of these crocodiles suddenly breaking through the mud of the
floor of his hut, beneath which it had retired for the dry season, is probably
familiar to most of our readers.

Long-Nosed Omitting notice of the small Johnston's crocodile (G. johnstoni),

Crocodile. o f North Australia, the last member of the genus is the curious long-
nosed crocodile (C. cataphractus), of West Africa, which forms a kind of connecting
link between the other true crocodiles and the garials. In this species the snout



is more elongated and slender than in any of its congeners, its length not unfre-
quently exceeding three times its basal width ; the bony union between the two
branches of the lower jaw being likewise of unusual length. In form the snout is
convex, and devoid of ridges ; while the region of the forehead is remarkable for
its convexity. The great peculiarity about the species is, however, to be found in
the arrangement of the bony plates 011 the neck, which form two longitudinal rows,
and are partially if not completely continuous with those of the back ; a some-
what similar arrangement existing in Johnston's crocodile. On the back the


number of longitudinal rows of shields is six; and the lower parts of the legs, as in
many other crocodiles, are furnished with a jagged horny fringe. In colour the
head is olive spotted with brown; the back and tail have a brownish yellow
ground-colour, with large black spots, while the yellowish white under-parts .-in-
marked with smaller white spots. In length this species reaches some 18 feet.

The long-snouted crocodile is found in the rivers and marshes of West Africa,
from Senegambia to the Gabun, and also occurs farther to the south in the Congo ;
its native name being khinh. Not unfrequently found in company with the Nile
crocodile, it inhabits the smaller streams and still waters of the interior, generally


'taking up its position in a deep pool protected by an overhanging bank or rock,
and thence sallying forth on its prey, which consists chiefly of fish, frogs, and
aquatic reptiles. The eggs are laid on the bank, where, unlike those of most other

; members of the family, they are carefully covered with leaves and herbage. Shy
and timid in its disposition, this crocodile is often captured by the natives for the

' sake of its flesh ; which, like that of many of its allies in other regions, is much
esteemed as food. While very abundant in the fresh waters of the interior, this

< species likewise haunts the salt-water lagoons of the Guinea Coast; and in the
delta of the Cameruns may be observed lying on the sandbanks bordering the
mangrove swamps, from which, on the approach of a boat, it darts into the water
with surprising celerity. There it often pulls down herons and such other aquatic
birds as may be standing or swimming in the water, sailing up to them with the
silence of a large fish, to which, when in the water, it presents a considerable

; resemblance. As in the estuarine and Nile crocodiles, in the adult of this species
the second tooth in the fore jawbone, or premaxilla, disappears, leaving only four
in place of the normal five on each side.

With the very lono; and slender-snouted crocodile from Borneo,
Schlegel's Garial. fo .

commonly known as fechlegel s garial (Jiriync/iosuchus scrilegeu), we

come to the first of two genera, each represented by a single existing Oriental
species, which differ very remarkably from any of those yet noticed. In both
those forms the snout is long arid slender, with its teeth-bearing margins nearly
straight, instead of being thrown into more or less well-marked festoons ; while
the nasal bones never extend forwards to reach the aperture of the nostrils, from
which they are separated by a considerable interval. Moreover, the bony union
between the two branches of the lower jaw is of great length, extending at least
as far back as the fifteenth tooth; and including a bone which in the other
crocodiles remains entirely separate from the symphysis. In neither do the
teeth attain the large dimensions characteristic of many other members of the

Schlegel's garial has the shorter snout of the two, its length not exceeding
three and a half times its basal width ; but it is especially distinguished by the
circumstance that the nasal bones extend forwards to articulate with the anterior
jawbones, or premaxillse. The teeth are twenty or twenty-one in number on each
side of the upper jaw, and eighteen or nineteen in the lower ; those on the sides of
the latter being received in pits between the upper ones, and the first, fourth, and
ninth lower teeth being enlarged. The bony plates on the neck and back form a
continuous shield consisting of four longitudinal, and twenty-two transverse rows ;
and while the fore-toes are webbed at the base, the outer ones of the hind-feet have
larger webs. In colour, Schlegel's garial is olive above, with dark spots or bars ;
while its length may be 12 or 14 feet. In habits this species is probably very
similar to the Indian garial. It is important to notice that several fossil repre-
sentatives of this genus occur in the Tertiary deposits of Europe, while it is not
improbable that the genus is also represented in the underlying Cretaceous rocks.
All this is exactly in harmony with what we should naturally have expected to be
the case, seeing that Schlegel's garial, like the true garial, is evidently a very
generalised member of the family.




Probably owing to a clerical error on the part of its first describer
the slender -snouted crocodile known in India by the vernacular
name of garial, is almost always spoken of in Europe as the gavial, while its mis-
spelt name has even been Latinised into Gavialis an error which some writers
persist in perpetuating. The garial (Garialis gangetica) is readily distinguished
at a glance from all other crocodiles by the exceeding length and slenderness of

OANGETIC GARIAL (^ nat. size).

its snout ; the length varying from more than five times the basal width in the
young to rather more than three in the adult. This narrow snout gives to the
reptile a decidedly curious appearance; and it is perhaps noteworthy that both
the garial and the gangetic dolphin, which inhabit the same rivers, and probably
feed on the same kind of food, have similarly elongated beak-like snouts, armed
with very similar curved and slender conical teeth ; this resemblance being doubt-
less due to adaptation to a similar mode of life. From Schlegel's garial, 1h-
present species is readily distinguished by the nasal bones being very short, and


consequently separated by a long interval from the anterior jawbones, or pre-
inaxillse ; while the teeth twenty-seven to twenty-nine on each side of the upper,
and twenty-five or twenty-six in the lower jaw are all of nearly uniform size,
and those of the lower jaw are not received into distinct pits. Moreover, the bony
union between the two branches of the lower jaw extends backwards to the
twenty-third or twenty-fourth tooth, whereas in the Bornean species it stops short
at the fourteenth or fifteenth. At its extremity the long and narrow snout
becomes much expanded ; and in the male this expanded extremity is surmounted
by a hollow hump, in the centre of which are placed the nostrils. The bony plates
of the neck form a shield continuous with that of the back, in which the number
of longitudinal rows is four, while there are twenty-one or twenty-two transverse
bands. Externally to the bony shields of the back there occurs on each side a row
of soft plates, which are either smooth, or but slightly keeled. The toes are well
webbed ; and the general colour of the adult is dark olive above ; the young being
pale olive, with dark brown spots or bars.

The garial has a somewhat curious geographical distribution, being restricted
to the Indus, Ganges, and Bramaputra, with their larger affluents, together with
the Mahanacli in Orissa, and the Koladyni River in Arakan. Together with certain
tortoises mentioned later on, this reptile is one of the most ancient of living
animals, its fossil remains occurring in the rocks of the Siwalik Hills in Northern
India in association with those of mammals belonging to extinct species and
genera. Attaining a length of fully 20 feet at the present day, and still larger
dimensions during the Pliocene period, the garial subsists solely upon fish, for the
capture of which its elongated narrow jaws, armed with numerous long, curved
teeth, are admirably adapted. There appears, indeed, to be no well authenticated
instance of these reptiles having attacked human beings or the larger mammals ;
and it is perhaps owing to this harmless disposition that they are held sacred in
many parts of India by the Hindus. In accordance with the nature of its prey,
the garial seems to be more thoroughly aquatic in its habits than most of its allies ;
the relatively long hind-limbs and the fully- webbed toes being features specially
suited to aid in swimming. In the breeding-season the female garial lays about
forty eggs in the sand of the river bank, these being deposited in two layers, and
covered to a considerable depth with sand ; the two layers being probably laid on
different days. The newly hatched young, which, from the great proportionate
length of their snouts, present a most extraordinary appearance, are very active,
and of a greyish brown colour, with five irregular dark oblique bands on the body,
and nine on the tail.

In addition to those of the existing species, the Siwalik Hills
Extinct Garials.

have yielded remains or several extinct garials, some or which attained

gigantic dimensions ; while other species belonging to the living genus have been
obtained from the middle Tertiary rocks of England. Possibly, also, certain fossil
garials from the Cretaceous deposits of the United States should find a place in the
same generic group. Other Cretaceous species are, however, remarkable for the
presence of a vacuity in the skull in front of the eye-socket, in consequence of
which they have been separated as a distinct genus, under the name of Thoracosaurus.
Mention must also be made of an enormous garial from the Siwalik Hills, known


as Rhampho&iwhus, which attained a length of some 50 or 60 feet, and had teeth as
large as those of the biggest crocodile ; its upper teeth biting on the outer side of
the lower ones, instead of interlocking with them, as in the living form.


As already mentioned, all the existing crocodiles, together with the species
from the Tertiary formations, constitute a single family, characterised by the
vertebrae having a ball in front and a cup behind, and by the internal nostrils
being situated at the hinder end of the skull ; as well as by the bony plates of the
back being arranged in at least four longitudinal rows. Although a few species
found in the topmost beds of the underlying Secondary formations approximate in
some respects to the foregoing, the majority of the crocodiles from rocks as old or
older than the Chalk differ very considerably from the existing types. In the first
place, the bodies of their vertebras articulate with one another by slightly hollowed
surfaces at both ends ; while, owing to the want of union between the hindmost
bones of the palate beneath the nasal passages, the internal apertures of the nostrils
are situated nearly in the middle of the skull. Then again, when a bony armour
is present, the plates on the back are arranged in only two longitudinal rows ;
while those on the lower surface of the body form two distinct shields. It is
remarkable that among these extinct crocodiles some are met with having broad
and short snouts like the modern alligators, while others have long and narrow
snouts like the garials. In the Wealden and Purbeck rocks, underlying the Chalk,
some of these crocodiles, such as the short-snouted Swanage crocodile (Goniopholis),
resembled living types in having the socket of the eye communicating freely with
the lower temporal fossa, although they were distinguished by the plates of the
back articulating together by means of a peg-and-socket arrangement. In still
older formations, such as the Lower Oolites and Lias, there were, however, many
long-snouted crocodiles, such as the steneosaurs (Steneosaurus) and pelagosuurs
(Pelagosaurus), in which the socket of the eye is divided from the lower tern pond
fossa by a bony bar, as shown in the figure on p. 13. Moreover, in these forms the
upper temporal fossa (T in the figure cited) was larger than the socket of the c\ < :
whereas in all living forms the former is much the smaller of the two, and may even
be obliterated. Another group of crocodiles, the metriorhynchs (Metriorhy m-h *),
of the Oxford and Kimeridge Clays, were remarkable in having no bony armour
at all, in which respect they were more specialised than any of their living cousins.
In general, however, the earlier extinct crocodiles, as will be gathered from tho
foregoing remarks, were decidedly of a less specialised type than those of the
present day ; and as a gradual transition can be traced in these respects from the
oldest to the most recent, the group affords a very interesting instance of progressive^
evolution. In the very oldest of the secondary rocks, namely, the Trias, there occur,
both in Europe and India, certain very remarkable long-snouted reptiles, known as
Parasuchians, which appear in some respects intermediate between crocodiles ;md
tuateras. Thus, while they resembled the former in the nature of their teeth, bony
armour, ribs, and vertebrae, they approximated to the latter in the structure of the
skull, abdominal ribs, and probably of the collar-bones and interclavicle.



Nearly allied to crocodiles are those remarkable extinct reptiles from the rocks
of the Secondary period, which include amongst their number the most gigantic
of all land animals, and likewise those members of the reptilian class which make
the nearest approximation in their organisation to birds. During that epoch of the


earth's history in which the Chalk and underlying Oolitic rocks were deposited,
when mammals were represented by a few small forms of lowly type, these strange
reptiles were the dominant animals on land; some progressing in the ordinary
lizard-like manner, while others stalked on their hind-limbs like birds. To give
some idea of the enormous dimensions attained by some of these creatures, it may
be mentioned that the thigh-bone of one species measures 64 inches, while the total
VOL. v. 3



length of its skeleton is estimated to have been between 60 and 80 feet. On the
other hand, some species were comparatively small, and not more than a couple of
feet in length. Although tlie whole of these reptiles are markedly distinct from
the crocodiles, yet they agree with them in the general charaetcrs of their
skulls, vertebra-, and ribs; but they differ so decidedly from one another that it is
not easy to give a definition of the entire order. They are, indeed, divided into
three well-marked groups, with so many differences between them that in the
opinion of many they are entitled to rank as separate orders ; and it will, accord-
ingly, be most convenient to treat these three groups seriatim.
Lizard-Footed The most stupendous members of the order are included in a

Group. group which may be conveniently designated lizard-footed dinosaurs,
on account of their walking in the ordinary lizard-like manner, and in having five
toes to the feet. The most striking peculiarity of this group is to be found in the


Journ. Geol. Soc., 1893.)


circumstance that the vertebrae of the neck and back, as shown in the accompany-
ing figure, had large cavities in their sides, which in the living state may have
been filled either with cartilage or with air. These vertebrae resembled those of
existing crocodiles, as described on p. 6, in having a ball at one end and a cup at the
other; but whereas in crocodiles the ball is at the hinder end of the body and the
cup in front, in these dinosaurs precisely the reverse of this arrangement obtained.
As regards their dentition, these reptiles had their teeth implanted in distinct
sockets, like crocodiles ; but the teeth themselves, as shown in the accompanying
figure, were of a peculiar spatulate shape, with the outer side convex and the innei
concave. Agreeing in the general structure of their pelvis with crocodiles, tin-si



dinosaurs were distinguished therefrom by the circumstance that the bone known
as the pubis (/> in the figure on p. 3) enters into the composition of the cavity
- reception of the head of the thigh-bone. The limb-bones are solid



(From the Quart. Journ. GeoL Soc. t 1893.)

for the

throughout. From the nature of
their teeth, which are often much
worn by use, it may be inferred
that these reptiles were vegetable
feeders; and it is not improbable
that they frequented the margins
of lakes and rivers, where their
inordinately long necks would
able them to browse with ease
the various aquatic plants,
at they must have been very
ggish in their movements and
stupid in their ideas is indicated
the wonderfully small propor-
ate size of their brains. These
dinosaurs were common both in

ope and the United States, the larger forms having been described under the
es of pelorosaurs (Pelorosaurus), atlantosaurs (Atlantosaurus), brontosaurs
and hoplosaurs (Hoplosaunis) ; among which the atlantosaurs
ipear to have been the most gigantic. They also occur in India, Argentina,
and Madagascar.

Carnivorous The carnivorous dinosaurs, of which the

| j/J J Group. megalosaur (Megalosaurus) is the best known

example, differed from the preceding group in the form of
\^, x^\. their teeth, which were compressed and sickle-shaped, with

2m ??**ieNJi . sharp cutting, and frequently serrated edges. Their limb-
bones also were hollow ; while their vertebrae were likewise
hollow internally, but had no lateral cavities ; and the
pelvis (figured on p. 3), although of the same general
type as in the lizard-footed group, presented important
points of distinction. In place of the short feet of the
last-named group, the carnivorous dinosaurs had elongated
foot -bones, terminating in sharp claws; the number of
functional toes in the hind-foot varying from four to three.
That they habitually walked on the toes of their hind-
limbs, and not (as was the case with the lizard-footed
group) on the whole foot, is evident from the structure of
this part of the skeleton, and from the circumstance that
the fore-limbs were considerably smaller than the hinder
pair, it may be inferred that progression was at least
frequently accomplished by the aid of the latter alone.
The close approximation of the huckle-bone of the ankle to

j"-j. \ir ^\ ^.AiVi>l V UlU'l .-> IT IT

DINOSAUR, the lower end of the tibia foreshadows the complete



amalgamation which takes place between those bones in birds ; while in one
remarkable American form the metatarsal bones of the foot were reduced to
three in number, and h;id nearly the same relationship to
one another and to the bones of the ankle as obtains in
birds. While the megalosaur attained a height, when erect,
of some 15 feet, the little Compsognathus, of the lithographic
limestones of Bavaria, did not stand more than 2 feet; and
there were other equally diminutive forms, both in England
and the United States, in which the whole backbone was so
permeated by air-cavities as to be little more than a mere
shell of bone.

The Bird-Like The whole of the dinosaurs mentioned

Group. above agree with one another in possessing a
pelvis approximating to the crocodilian type ; that is to say,
the pubis or anterior lower bone of this part of the skeleton is inclined down-
wards and forwards, and thus diverges in the form of an inverted Ffrom the


After Gaudry.


backwardly and downwardly directed ischium, or posterior lower bono, as show
on ilic figure on p. 3. On. the other hand, in the bird-like dinosaurs the mail




b:ir of the pubis is inclined backwards, parallel to the ischium, while it has
a secondary plate projecting forwards. In this parallelism of the pubis and
isehium these dinosaurs resemble birds (see the figure in Vol. III. p. 290), and birds
alone; and from this and other features it is pretty certain that the latter are
derived from reptiles more or less closely allied to this or the preceding group of
dinosaurs ; the resemblance in the one case being closest in the structure of the
pelvis, and in the other of the hind-limb. All the bird-like dinosaurs are further
characterised by the presence of a separate chin-bone (pel in the figure on p. 3)
at the extremity of the lower jaw ; by the
absence of teeth from the front of both
jaws ; by the teeth themselves approximat-
ing more or less closely to the type of the
one here represented, and by being fre-
quently not implanted in distinct sockets;
and likewise, by the vertebras being com-
pletely solid throughout. The typical
representatives of this group are the well-
known iguanodons, originally described on
the evidence of teeth, from the Wealden
rocks of England, but now known by
entire skeletons from the corresponding
deposits of Belgium, which are exhibited in
the museum at Brussels. These reptiles,

hich were represented by allied forms in the United States, habitually walked
their three-toed hind-limbs, the largest individuals attaining a length of some
3 feet. They are characterised by the limb-bones being hollow, by the length
f the metatarsal bones of the foot, by the first digit of the five-toed fore-limb
ing converted into a large conical spine, and also by the teeth being of the type
f the one shown in the accompanying figure. Needless to say, animals with

such teeth must have been purely vegetable
feeders, as indeed were all the other members
of this group. The hind - feet terminated in
rather sharp claws, and there was no bony
armour on the body. The iguanodons probably
stalked about among the palm -forests of the
Wealden period, on the leaves and fruit of
which they may be presumed to have in great
part subsisted. In these reptiles the large

flattened and serrated teeth were arranged in each jaw in a single row, but in cer-
tain smaller forms known as trachodons, a. b c
which occur in the higher Cretaceous
rocks of both Europe and North America,
there were several rows of teeth in use
at the same time, the edo;es of these


teeth being so flattened and fitted to-


gether that a pavement- like structure DINOSAUR. After Marsh.


After Marsh.


resulted. These trachodons were all much inferior in size to the gigantic
iguanodons. The American claosaur (ClaosaMrus), of which the skeleton is figured
on p. 36, differs from the iguanodons in having the fore-paw of normal structure.
Nearly allied to the iguanodons are the remarkable armoured and horned dinosaurs,
which constitute a subgroup characterised by their solid limb-bones, the presence
of some kind of bony armour, the short foot-bones, frequently terminating in

hoof-like toes, and the
habitually quadrupedal
gait. Commencing in
the British Lias, these
extraordinary reptiles
continued throughout
the Secondary period,
and seem to have at-
tained their maximum
development at the close
of the Cretaceous epoch
in the United States. Of
the armoured forms, the
huge stegosaur of the
English Oxford, and
Kimeridge Clays, and
the corresponding rocks
of the United States, was
characterised by the
possession of large quad-

Online LibraryRichard LydekkerThe new natural history (Volume 5) → online text (page 5 of 62)