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monitor, Cantor says that it is "very numerous in hilly and marshy localities of
the Malayan Peninsula. It is commonly during the day observed in the branches
of trees overhanging rivers, preying upon birds and their eggs and smaller lizai
and when disturbed it throws itself from a considerable height into the water. It
will courageously defend itself with teeth and claws and by strokes of the tail.
The lowest castes of Hindus capture these lizards commonly by digging them out
of their burrows on the banks of rivers, for the sake of their flesh." Professor V.
Ball gives the following account of a meeting with a lizard of the same species in
the Nicobars: "As I did not care to shoot him, though I wanted to capture him, I
threw stones at him, whereupon he hissed and lashed his tail in a manner that



GREAVED LIZARDS. I53

might prove alarming to anyone not knowing the harmless nature of the beast. As
I was pressing him into a corner, he made a rush into the waves, but returned,
apparently not liking the surf. Just as I thought he could not escape, he made a

idden dart into the water, dived through the surf, and disappeared."

From observations made on specimens in captivity, it appears that these
lizards eat eggs by taking them in their mouths, raising their heads, and then
Breaking the shells, so that the contents are allowed to run down their throats.

Jthough but little is ascertained regarding their breeding-habits, monitors are
:nown to lay white, soft-shelled eggs, which are deposited sometimes in the nests
jf white ants. As many as twenty-four eggs, of a couple of inches in length, have
)een taken from the body of a single female. By the Burmese these eggs are

mch relished as articles of food, and command a higher price in the market

lan hens' eggs.

THE GREAVED LIZARDS.
Family TEIID^E.

In America the place of the true lizards of the Old World is taken by a nearly
illied group which may be termed the greaved lizards, some of which rival the
smaller monitors in size. In common with the remaining members of the
iborder, these lizards are distinguished from all the foregoing by their tongues,
rhich are slit at the tip and frequently shaped like an arrow-head, being either
>vered with overlapping scale-like papillae, or marked by oblique folds. In all,
10 head is covered with large symmetrical shields, very different from the small
sales of the monitors. They further differ by the collar-bones being dilated, and
rften loop-shaped at their inner extremities.

The greaved lizards are specially characterised by the absence of a bony roof
the temporal fossae of the skull, and by the shields of the head being completely
free from the underlying bones ; while there are no bony plates on the body. On
le body and tail the scales are arranged in transverse rows. The teeth, although
, r ery variable, differ from those of the true lizards of the Old World in not being
lollow at the base ; the replacing teeth being developed in small sockets at the
roots of those in use. In some cases these teeth, which may be either pointed or
of a flattened crushing type, are placed near the summits of the jaws, and in others
somewhat on the side, so that the dentition is intermediate between the typical
acrodont and pleurodont modifications ; the front teeth are always conical. On
the palate teeth are but seldom present, and, if developed, are small. The long
tongue, which is frequently retractile within a sheath, is generally covered with
overlapping scales ; the drum of the ear is exposed ; and the eyes are generally
furnished with lids. The majority of the forms resemble the true lizards in
general appearance, although in some the number of toes is reduced to four. In
others, however, the limbs take the form of mere stumps, while the hind pair may
be wanting, in which case there is a near approach to the amphisbaanas.

The greaved lizards comprise over a hundred species, arranged in thirty-five
genera, which are distributed over the warmer parts of America, although most
mmerous in the equatorial regions. Various in their habitat, some frequent dry,



1 54 LIZARDS.

sandy plains, others dwell among the herbage of meadows, while others prefer
woods, and a few are partially or wholly subterranean; these latter either taking
possession of some empty hole, or digging one for themselves. In their general
i noile of life they resemble the monitors and true lizards, although some are more
like the amphisbaBnas. They are generally swift and active in their movements ;
and the larger kinds are thoroughly carnivorous, subsisting not only on insects,




THE TEJU (i nat. size).

worms, slugs, and snails, but likewise hunting such of the smaller vertebrates as
they are able to overcome. Most species deposit their eggs in the hollow .stems, or
among the roots of trees. A few of the larger species are hunted for the sake of
their flesh, which is stated to be tender and well-flavoured

One of the largest and best known representatives of the family

is the lizard variously termed the teju, teguexin, or jacunru

(Tupinambis teguexin), which ranges over a large portion of South America and

the West Indies, and belongs to a genus comprising tlnvr species. These li/anls



GREAVED LIZARDS. 155

may be recognised by the tail being round at the root and slightly compressed
near the middle, the double fold of skin on the neck, the uniform scales of the
back, the rather small squared shields of the under surface of the body, which are
arranged in more than twenty rows, the want of teeth on the palate, the com-
pressed tricuspid cheek-teeth of the young, and the long tongue, which is of nearly
equal width throughout, and sheathed at the base. In old individuals the crowns
of the cheek-teeth become obtuse. The teju, w T hich attains a length of about a
yard, is a bulky and strikingly coloured lizard. Above, the ground-colour is olive,
upon which are markings and bands of black, and more or less distinct rows of




XA.M AMEIVA (\ Hat. size).



lighter spots ; while the under surface is yellowish, with interrupted black bars ;
the lines of division between the shields of the head being black.

Ranging from Guiana to Uruguay, the teju is said by Bates to be very
common in the forests of the Amazon, where it may be observed in numbers
during the midday stillness scampering, apparently in sport, over the dead
leaves ; while in other districts it haunts sugar-plantations. Although frequently
found in the neighbourhood of water, it apparently never enters it; arid
generally dwells in wide-mouthed holes situated beneath the roots of trees. Shy
and retiring to a degree in inhabited districts, when driven into a corner it shows
fight, hissing at and striking with its muscular tail the dogs employed in its
pursuit. When sitting, the head is generally raised, while the forked tongue is
in constant motion. Its diet comprises such living creatures as it can capture,



156 LIZARDS.

together with eggs. The female lays from fifty to sixty hard-shelled eggs about
the size of those of a pigeon, generally placed in the hillocks of white ants.

The dracaena (Draccena guianensis), of the Guianas and Amazonia, is a
somewhat smaller lizard, distinguished by its compressed and doubly-keeled tail,
the intermixture of keeled tubercles among the scales of the back, and the
extremely broad crowns of the cheek-teeth.

Our second figured representative of the family is the Surinam
TheAmeivas. . . . .

ameiva (Ameiva surinamenfns), belonging to a genus ot nearly

twenty species distributed over Central and South America, where they take the
place occupied by the true lizards in the Old World. They are distinguished by
their round, keelless tails, the presence of less than twenty rows of large smooth
scales on the under surface of the body, and the compressed two- or three-cusped
cheek-teeth. The tongue can be withdrawn into a sheath. The figured species,
which is found over South America as far as Nicaragua, attains a length of from
15 to 20 inches, and is very variable in coloration. The young arc olive-brown,
with darker markings or white dots, and a black, white-edged band running along
the side of the body and extending on to the tail; these bands generally disappear-
ing with age, although sometimes retained in the females. In the adult the upper
surface is usually greenish, with some black and a few white spots: while the
under-parts are greenish white, spotted with black on the sides. Ameivus are
generally found in dry districts more especially near the coasts, and in their
general habits are not very different from the teju, usually living in holes, anion^
old wood, or the herbage of gardens.

THE AMPHISB^NAS.
Family AMPHISB&NIDJE.

Among the most remarkable of all lizards are those whose typical repre-
sentatives have the power of moving equally well either backwards or forwards,
from whence they derive the name by which the group is now commonly
designated. Very nearly related to the preceding family, through those members
of the latter with aborted limbs, the amphisbaenas are distinguished by the simple
and degraded characters of the skull, in which all the arches have been lost,
and the two premaxillary bones are fused into one. All are adapted to a purely
subterranean existence, and have long, worm-like bodies, devoid, except in on,
species, of any external trace of limbs; while even the bones of the shoulder aiu
pelvis are more or less rudimental. The eyes are concealed beneath the skin ; the
mouth is small, and frequently inferior in position; and the ear is completely
wanting. Although the head is covered with large symmetrical shields, the skin
of the body is divided into squared segments forming regular rings, like those of
worms; from which character the group is sometimes spoken of as the ringed
li/ards. In all the tail is short. The large teeth are few in number, and fixed
either to the inner or upper edges of the jaws.

The amphisbaenas, which are arranged in eleven genera, including between
sixty and seventy species, are most numerously represented in America south of



AMPHISBAENAS. 157

the Tropic of Cancer, although also occurring in the West Indies, while Africa
possesses over twenty species, and four are found in the Mediterranean area. Of
their habits, Mr. Boulenger observes that all the members of this family are
burrowers, and may live in ants' nests. They bore narrow galleries in the earth,
in which they are able to progress backwards as well as forwards. On the ground
they progress in a straight line by slight vertical undulations, not by lateral
movements, as in other limbless reptiles ; and the tail of many species appears to
be more or less prehensile. The food of these lizards consists of small insects and
worms. As regards their breeding-habits, it is only known that one species lays
eggs, which are deposited in ants' nests. The marked resemblance of these lizards
to earth-worms is a most curious instance of the similarity produced in the external




HANDED AMPHISB^ENA (liat. size).

form of different groups of animals by adaptation to similar modes of life ; the
remarkable feature in this case being the occurrence of this resemblance in
creatures so widely sundered from one another, as are worms and amphisbaenas.
Fossil members of the family have been discovered in the Tertiary rocks of North
America.

Handed The one member of the family which exhibits evidence of its

Ampnisbsena. relationship to less specialised lizards in the retention of rudimentary
fore - limbs is the handed ainphisbsena (Chirotes caniculatus), of Mexico and
California ; this being one of the two species found on the continent of America to
the north of the Tropic of Cancer. This creature, which attains a length of about
7 inches, and is of a brownish flesh-colour, is distinguished by the presence of
a pair of small depressed fore-limbs, placed close to the head, to which they are
about equal in length ; each of these being provided with four well-developed and
clawed toes, of which the outermost is the shortest.



'58



LIZARDS.



Typical
AmpMsbaenas.



The typical members of the family constitute a genus (Am i>h'i*-
common to Tropical America and Africa, and represented by
nearly thirty species. Belonging, like the last genus, to the group in which the
teeth are attached to the inner edges of the jaws, these limbless amphisbaenaa are
specially characterised by the anterior body-rings not being enlarged, by the
laterally placed nostrils being pierced in a special nasal shield, by the rounded or
slightly compressed snout, the obtuse, cylindrical tail, and the presence of pores in
front of the vent. The figured species (A. fuliginosa) is a well-known kind from
Tropical America and the West Indies, deriving its name from its pied skin, and
attaining a length of about 18 inches. Writing of the habits of a member of the
genus, Bates observes that their " peculiar form, added to their habit of wriggling
backwards as well as forwards, has given rise to the fable that they have two
heads, one at each extremity. They are extremely sluggish in their motions, and
live habitually in the subterranean chambers of the satiba ant ; only coming out




SPOTTED Aill'HISB^NA ( Hat. size).

of their abodes occasionally in the night-time. The natives call the amphisbaena
the mai das saubas, or mother of the salibas, and believe it to be poisonous,
although it is perfectly harmless. It is one of the many curious animals which
have become the subject of mythical stories with the natives. They say the ants
treat it with great affection, and that if the snake be taken away from a nest the
saubas will forsake the spot. I once took one quite whole out of the body of a
young jararaca [a poisonous snake], whose body was so distended with its contents
that the skin was stretched out to a film over the contained amphisbsena. I was,
unfortunately, not able to ascertain the exact relation which subsists between
these curious reptiles and the saiiba ants. I believe, however, that they feed upon
the saubas, for I once found the remains of ants in the stomach of one of them."



THE TRUE LIZARDS.
Family LACERTID^!.

The true lizards, constituting the typical representatives of the suborder, form
a large family, with seventeen rv ^ distributed over Europe, Asia, and Africa



TRUE LIZARDS. 159

(exclusive of Madagascar), but most abundant in Africa, and comparatively rare in
the Oriental countries. Taking the place in the Old World occupied in the New
by the greaved lizards, these reptiles are readily distinguished from the latter by
the temporal fossa of the skull being roofed over with bone (as shown in the figure
of the skeleton on p. 108), and likewise by the shields of the head being firmly
attached to the underlying bones, as well as by the union of the two premaxillary
bones, the latter feature being common to this family and the amphisbaenas. All
of them have well-developed limbs, each furnished with five toes, the body plump,
and separated by a well-marked neck from the head, the tail long and brittle, the
drum of the ear exposed, and the eyelids distinct and generally freely mobile. The
skin contains no bony plates; the scales of the back are either overlapping or in
apposition ; while those of the under surface are generally larger, and arranged in
longitudinal and transverse rows. The teeth are always attached to the sides of
the edges of the jaws (pleurodont), and differ from those of the grooved lizards in
their hollow bases ; those of the cheek-series having two- or three-cusped. crowns.
The flat and scaled tongue is of considerable length, and cleft both in front and
behind, so as to assume the form of an arrow-head. As a rule, pores are present
on the hinder surface of the thigh.

Out of about one hundred species of true lizards, two are found in the British
Islands, where, with the exception of the blind-worm, they are the only represent-
atives of the suborder; but many others inhabit Southern Europe. Lizards of
this family are veritably creatures of the sun, delighting to bask in its rays on
some warm sandy bank, wall, or rock, and retiring to their holes and crannies in
cloudy or rainy weather. The more powerful and bright is the sun, the more
active, indeed, do these reptiles become, since most of them are dull and listless in
the mornings and evenings, and only wake to full activity in the midday glare.
Over the greater part of Europe they begin to spend a large portion of their time
in their holes, and with the commencement of October retire for their winter sleep,
from which they do not awake till spring is well advanced. Comparatively rare
in Northern Europe, in the south of the continent lizards are common enough to
form an attractive feature in the landscape, their burnished metallic green and
bronzy scales flashing in the sunlight on every wall, and in every road and path.
The darting movements of these pretty reptiles, as they are in pursuit of the flies
and other small insects which constitute their chief prey, are familiar to all.
While the majority lay eggs, the viviparous lizard produces living young.

The pearly lizard (Lacerta ocellata) of Southern Europe, which
is also represented by a variety in Algeria, may be taken as our first
example of the typical genus Lacerta, of which there are over twenty species,
inhabiting Europe, North and West Asia, Africa north of the Sahara, and the
Atlantic islands. The members of this group, which may be collectively designated
collared lizards, are distinguished by the following features. The body is cylindrical
or slightly depressed ; the head pyramidal, with upright sides ; the neck not very
well defined ; and the tail cylindrical, tapering, and long. The throat is furnished
with a well-marked collar of enlarged scales ; the scales on the back are smaller
than those on the tail, and are at most but slightly overlapping; while the shields
of the under surface are squared, and sligl A- a-lapping. The rounded or com-



160 LIZARDS.

pressed toes have either smooth, tuberculated, or indistinctly keeled pads on the lower
surface, while the thighs have pores. In common with several other genera, the
nostrils are placed close to the so-called labial scales, from which they are separated
at most by a narrow rim ; and if there be a transparent disc in the lower eyelid,
it is smaller than the eye. Among the most beautifully coloured members of
the suborder the pearly lizard, which attains a length of from 16 to 23 inches,
claims a foremost place. Belonging to a large group of the genus, in which the
edge of the throat-collar is strongly serrated, this species agrees with certain other
members of the genus in its smooth tail, and in the scales on the sides of the body
not being smaller than those on the back. As special characters of the species, it
may be noted that the scales are smaller than in the allied forms ; and that there
are not less than seventy scales round the middle of the body, eight or ten of which
belong to the under surface. The head is very large in the male, and characterised
by the great width of its hindmost, or occipital, median shield. In colour, the
upper-parts are either green, with black dots or network, or blackish olive with
yellowish netting ; the sides are marked with a row of about a dozen eye-like blue
spots ; while the under surface is uniform greenish yellow. The olive-coloured
young are, however, dotted all over with white, or pearly-blue, black-edged spots.

Common in Spain, and also occurring in the south of France and North-
Western Italy, or wherever the olive-tree grows, the pearly lizard is generally to
be met with in the neighbourhood of hollow trees, frequently ascending some
distance up their trunks, or even climbing among the branches. The males are
somewhat quarrelsome, and the females lay from six to ten eggs, generally
deposited in a hollow olive-tree.

Another well-known European species is the L r reen lizard
Green Lizard.

(L. viridis), attaining a length of about 12 inches in Germany, but

in the more southern portions of its habitat measuring as much as 17 inches;
fully two-thirds of this length being occupied by the long tail. Having not more
than sixty-six scales round the middle of the body, this lizard is distinguished by
the general presence of two small superimposed scales behind each nostril, the
small size and triangular form of the occipital shield, and the arrangement of the
abdominal scales in six longitudinal rows; the collar being serrated. Usually the
nostrils are in contact with the front or rostral shield of the head : and in the
female and young the foot is longer than the head. As regards colour, the males,
which may be distinguished from the females by the larger and higher head, the
thickened root of the tail, stouter hind-limbs, and generally superior size, are some
shade of green-olive, passing below into yellow. Black dots, passing into large
spots, generally adorn the upper surface, whereas the under-parts, save for a blue
patch on the chin and throat, are uniform. The females, in which the blue on the
throat is less constantly present, have a more brownish tinge, with tin- sides
ornamented with black-bordered yellowish spots. The young arc generally leather-
brown in colour, with one or two yellow side-stripes. Both sexes vary, limvever,
considerably according t<> age; and southern specimens are more brilliantly coloured
than those from the north.

The green lizard is an inhabitant of the countries lying to the east and nortli
of the Mediterranean, and thence extending eastwards to Persia. Very common in



TRUE LIZARDS.



161



Portugal and Spain, where it is represented by a variety, it extends in France as
far north as Paris, but it is unknown in Sardinia. In place of resorting, like the
pearly lizard, to trees, this species is usually found on the ground, more especially
in districts where the subsoil is rocky, ranging from the sea-level to a height of
some three thousand feet, and being equally at home on the plains or among the
mountains, in stony or sandy districts, on bare rocks, or among thick bush. As
rapid as lightning in its movements, it feeds chiefly upon large insects and their
larvae, together with slugs and worms ; living in grassy districts almost entirely upon
grasshoppers, and at times attacking smaller species of its own tribe. In Switzer-
land and Germany the female usually deposits her eight to eleven white eggs




Sand-Lizard.



GREEN LIZARDS ( liat. size).

during June, these being hatched in the course of a month or so; and it is
generally during the breeding-season that the blue on the throat is assumed by
this sex.

The third European representative of the genus is the much
smaller sand-, or hedge-lizard (L. ayilis}, which is a more northern
form, ranging into the British Islands and Scandinavia. Usually not more than
8 inches in length, although occasionally measuring nearly 10, this lizard may be
recognised by its short, thick, and blunt-snouted head, and by the tail being
considerably less than twice the length of the head and body. Never having more
than fifty-eight scales round the middle of the body, it is further distinguished by
the rostral shield of the head being separated by a small interval from the nostrils,

VOL. V. II



162 LIZARDS.

by the trapezoidal shape of the small occipital shield, by the absence of the row of
small granules which occur between the shields of the eyelids (supraoculars) and
eyebrows (supraciliaries) in the green and wall-lizards, and by the foot being not
longer than the head. Although there is great variation in this respect, the
general colour of the male is greenish, and that of the female grey or brown; the
crown of the head, a streak down the back, and the tail being mostly brown, while
the chin and under-parts are greenish or yellowish. Tli3 streak down the back,
and in the females also the sides, are marked by rows of white spots, which are
sometimes large and eye-like ; and the under surface is marked with black. Some
individuals, especially males, closely approach the green lizard in coloration.

The range of the sand-lizard embraces North, Central, and Eastern Europe,
and extends eastwards to Western Siberia and Asiatic Russia. In England it is
generally found on sandy heaths, where it may often be seen running across the
open paths with a speed less rapid than that of the more common viviparous
species. It is more timid and less easily tamed than the green lizard, generally
pining and refusing to feed in captivity. According to Bell, the female lays her



Online LibraryRichard LydekkerThe new natural history (Volume 5) → online text (page 18 of 62)