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eggs, to the number of twelve or fourteen, in hollows in the sand, which she
excavates for the purpose, and having covered them carefully with sand, she
leaves them to be hatched by the solar heat.

viviparous. A still smaller, and at the same time a more slightly built

Lizard. species is the common English viviparous lizard (L. vivipara), which
varies in length from 6 to just over 7 inches in length. It has larger scales than
the last, which are not more than forty-five round the middle of the body, and the
foot generally exceeds the head in length; granules being absent above the eyes.
The absence of teeth on the palate is another feature in which this species differs
from the sand-lizard. The colour of the adult is brown, yellowish, or reddish,
ornamented with small dark and light spots, and often with a dark streak down
the back, and another, edged with yellowish, on each side. In the male, the under
surface is orange or vermilion, spotted with black ; and in the female, pale orange
or yellow, sparsely spotted with black, or uniform. The young are nearly black,
and this hue occasionally persists. Unknown to the south of the Alps, the
viviparous, or, as it is sometimes called, mountain-lizard, is spread over the greater
part of North and Central Europe, and the whole of Northern Asia, as far as
Amurland, ranging in the Alps to a height of nearly ten thousand feet. At this
elevation it is, however, dormant for fully three-quarters of the year, being active
for only two or three months. In Britain it extends to Scotland, and is one of
the few reptiles found in Ireland. Generally similar in its habits to its allies, it
is more fond of water, and is a good swimmer, usually frequenting heaths and
banks. " Its movements," writes Bell, " are beautifully graceful as well as rapid ;
it comes out of its hiding-place during the warm parts of the day from the early
spring till autumn has far advanced, basking in the sun, and turning its head
with a sudden motion, if an insect comes within its view, and, darting like
lightning upon its prey, it seizes it with its little sharp teeth, and speedily
swallows it." Unlike its kin, this species produces living young, varying from
three to six in number, which are active as soon as born, and remain in the
company of their parent for some time.




'



WALL-LIZARDS.



TRUE LIZARDS.



163



w 11 Lizard re P resen ^ a ^ ve ^ the typical genus that we shall notice

is the beautiful wall-lizard (L. muralis), of which a group is depicted
in our coloured Plate. This southern species, which inhabits the countries
bordering both sides of the Mediterranean, and extends eastwards into Persia,
belongs to a group in which the edge of the collar on the neck is even or but
slightly serrated, and the scales of the back are granular. Attaining in Germany
a length of from 7 to 7i- inches, but reaching from 8 to 9^ inches in Italy, this
species has a scries of granules between the shields above the eyes, while the scales
of the abdomen are arranged in six (rarely eight) rows, and those on the upper
surface of the leg are larger than those on the back ; and there is but a single




VIVIPAROUS LIZARD (uat. size.)

(postnasal) scale behind each nostril. In colour the wall-lizard presents such an
astonishing variation, that it is almost impossible to give any general description.
In German examples the ground-colour of the back is, however, often brown or
grey, with bronze-green reflections in sunlight, upon which are blackish streaks,
marblings, and spots ; while the flanks have a row of blue spots ; and the under-
parts vary from milk-white to copper-red, frequently variegated by spots or
marblings. In Southern Europe these lizards maybe seen basking on almost every
wall, old building, or face of rock, where they delight all beholders with their
activity and tameness. " Scarcely two," writes Leith-Adams, " are marked alike ;
the brightness and variety of their hues are most beautiful and attractive, and, like
the chamaBleon, they change colour with the coruscations of sunshine, but, of



164



LIZARDS.



course, not to the same extent. During an excursion to the islet of Filfla, on the
southern coast of Malta, in the month of June, I was surprised to find that all the
lizards on the rock were of a beautiful bronze-black, and so much tamer than their
agile brethren on the mainland. Many individuals were so tame that they
scrambled about our feet, and fed on the refuse of our luncheon." Whereas in the
Southern Tyrol these lizards remain active till December, and reappear by the





ALGERIAN KEELED LIZARDS (f liat. size).

middle of February, in Germany their winter sleep is considerably longer. Like
its congeners, this species has an exceedingly brittle tail; and it was observed
some years that on a certain road in Madeira all the lizards belonging to a nearly
allied species (L. dugesi) were without tails. The circumstance was explained
by the spot being the favourite resort of the midshipmen landing from the ships
visiting the island, who amused themselves by knocking off the lizards' tails.

The members of the genus Lacerta, as we have seen, are
' characterised by the presence of a well-marked collar on the neck, by



TRUE LIZARDS.



165



the scales of the back being smaller than those on the tail, and by the toes being
without fringes on their sides, or keels on their soles. An allied genus Algiroides
represented by three species from the eastern coast of the Adriatic, Greece,
Sardinia, and Corsica, differs by the strongly overlapping scales of the back being
nearly as large as those of the tail. On the other hand, four species inhabiting
South- Western Europe and the opposite coast of Africa constitute a third genus
Psammodromus in which the collar is indistinct or wanting, the toes are not
fringed, though generally more or less distinctly keeled interiorly, while the over-
lapping scales of the back bear strong keels. Among these the Spanish keeled
lizard, or sand-runner (P. hispanicus), retains a trace of a collar and has strongly
keeled soles; whereas in the Algerian keeled lizard (P. algirus) the collar is



COMMON FRINGE-TOED LIZARDS (nat. size).




wanting, and the soles are at most but feebly keeled. The figured species, which
inhabits not only North- Western Africa, but likewise Portugal, Spain, and the
south of France, reaches nearly 10^ inches in length, and has a tail almost twice as
long as the head and body. It is specially distinguished by the scales of the
abdomen being of nearly equal width and arranged in six rows, as well as by the
presence of from thirty to thirtj^-six scales round the middle of the body. In
colour, this lizard is bronzy -green above, with one or two golden, dark-edged
streaks along the side ; the male being ornamented with a pale blue eye-like
spot above the shoulder, sometimes followed by one or two behind, w r hile the
tinder-parts are whitish. Abundant in Algeria and the neighbourhood of Mont-
pellier this lizard is found in the former region both in hedges and on limestone
rocks, whereas in France it frequents hedges alone. Preferring dry, open, and



1 66 LIZARDS.

warm districts, and thriving well in captivity, it presents nothing specially note-
worthy as regards its habits.

Fringe-Toed The fringe-toed lizards (Acantkodactylus), of which there arc

Lizards. ten species ranging from Southern Spain and Portugal, and Northern
Africa through South- Western Asia to the Punjab, differ from the preceding group
by the toes being both fringed on the sides and keeled below ; a more or less
distinct collar occurring on the throat. On the head, the occipital shield is
wanting, and the nostrils are pierced between two nasal and one labial shields.
Pores are present on the thigh, and the tail is nearly cylindrical. The common
fringe-toed lizard (A. vulgaris) is a species of from 4J to 4f inches in length,
agreeing with most of its kindred in having the hinder scales of the back but little
enlarged, and specially characterised by the strong keeling of the scales on the
upper surface of the tail, and the slight pectination of the toes. It is represented
by two varieties, one occurring in Spain and Portugal, and rarely in the south of
France, characterised by the smooth or slightly keeled scales of the back, and an
African form in which these scales are very strongly keeled, and the coloration is
brighter. The colour of the adult is greyish or brownish, with faint longitudinal
series of light and dark spots and lines, and sometimes eye-like blue spots on the
flanks ; the young being longitudinally streaked with black and white, and having
white spots on the limbs. All these lizards inhabit dry sandy districts, and are
remarkably shy in their habits, seldom venturing forth from their retreats except
when the sun is shining brightly.



THE SKINK TRIBE.
Family SciNCID^;.

The preceding family is connected with the one we have now to consider by ;i
small group of five African genera constituting the family Gerrhostmr'nlit', which,
while resembling the true lizards in having but a single premaxillary bone and
the presence of pores on the thigh, agree with the skinks in possessing bony plates
of peculiar structure beneath the scales. The skink tribe, taking their title from
the lizard commonly known by that name, are a very numerous family, comprising
upwards of twenty-five genera and nearly four hundred species, and presenting
great variety of bodily form, some kinds being four-limbed, while others are
or less completely snake-like. Agreeing with the true lizards in the characters
the tongue and teeth, as well as in the roofing-over of the temporal fossae by boi
the skinks differ in having two distinct premaxillary bones in the skull, in tl
presence of bony plates traversed by symmetrical tubules beneath the scales, ai
in the invariable absence of the pores which are generally present in the thighs
the LacertidcG. The limbs, when present, are relatively short, and in sonic
are reduced to two, and in others absent; the number of toes is very vnrial
even among the members of a single genus ; the short and scaly tongue is fi
and but slightly notched in front ; and the drum of the ear is generally covei
with scales. The eyes have round pupils, and well -developed and generally mobi
lids, the lower one of which has a large transparent window. The teeth, whic



SKINK TRIBE.



167



are attached to the sides of the jaws, may have either conical, bicuspid, or broad
and spheroidal crowns (Tiliqua). The head is covered by large symmetrical
shields, among which an unpaired occipital is generally wanting; and the over-
lapping scales of the body are generally subhexagonal in form and arranged in
a quincuncial manner. Worldwide in distribution, the skink tribe are most
numerously represented in Australia, Oceania, the Oriental region, and Africa,
while very few occur in South America, and there are not many in North America
and Europe. Although their habits are not fully known, it appears that, with the
exception of two genera, they bring forth living young, varying from two to ten
in number. The majority are terrestrial, a few only being able to climb, while
none are aquatic. They sedulously avoid the neighbourhood of water, frequenting




STUMP-TAILED LIZARDS (* nat. Size).

Iry situations, and more especially those where the soil is sandy with an admixture
jf pebbles or fragments of rock. Moreover, they generally possess the faculty
rare among lizards of burrowing in the ground with the dexterity, if not with
the power, of moles. From this habit the group is sometimes spoken of as the
Burrowing lizards; and it may be remarked that their spindle-shaped bodies,
covered with highly polished scales, their short legs, and frequently abbreviated
tail, as well as the transparent window in the lower eyelid, are all features specially
adapted for such a mode of life. From among the numerous genera, the limits of
our space render it necessary to confine our remarks to four, which are selected as
examples of very divergent types.

stump-Tailed Described as far back as the year 1699, the stump-tailed lizard

(Trachysaurus rugosus), of Australia, is the sole representative of



Lizard.



i68



LIZARDS.



one of the most remarkable genera in the entire suborder. With a short,
pyramidal depressed head of great width, a short but distinct neck, a long, thick,
and flattened body, and a very wide and stumpy tail, the creature is clothed with
an armour of rough, thick, brown scales, which give it very much the appearance
of a living pine-cone. On the lower surface, the scales are smooth and much
smaller. The small and stout limbs are widely separated, and terminate in five
short toes, each provided with strong curved claws. In length this strange reptile
measures about 14 inches, and its colour above is brown with spots or irregular
bands of yellow, while beneath it is yellowish, with brown spots, marblings, or
longitudinal and transverse streaks. The cheek-teeth have subconical crowns.

O

Beyond the fact that it is a burrower, scarcely anything appears to be known of
the habits of the stump-tailed lizard in a wild state, although many observations
have been made on captive specimens. In the latter state it is slow and lethargic




EUROPEAN SNAKE-EYED LIZARD (nat. size).

in its movements, creeping about with the abdomen pressed to the ground. Its
chief food consists of worms and insects, although fruit and vegetables are
occasionally eaten; and that it can endure long fasts is proved by an example
which only ate two or three flies during the voyage from Australia.

Snake-Eyed Very different in appearance to the last is the lizard (Ablepharus

Lizards. pannonicus) represented in the accompanying illustration, which
belongs to a genus containing a number of small species distributed over Austral in.
South- Western Asia, South-Eastern Europe, and Tropical and South America, one
of which (A. boutoni) ranges irregularly over the hotter parts of both the Eastern
and Western Hemispheres. These lizards difl'er from all their kin in having no
movable eyelids, their place being taken by a transparent disc of skin (stretched
over the eye after the manner of snakes. In this genus the ear may be either
open or concealed by scales ; and while some of the species have well-developed
limbs, in others they are more or less aborted, the number of toes being also
highly variable. The figured species, which ranges in Europe from Hungary to



SKINK TRIBE.



169



Greece, and is also spread over Asia Minor, Syria, and Northern Arabia, measures
only 4 inches in length, of which fully half is occupied by the tail. Its general
colour above is bronzy olive, becoming darker on the sides, and with a blackish
light-edged streak passing through the eye along each side of the body ; while the
under-parts are greenish. The European species is found alike on slopes covered
with short grass or in sandy spots, and does not appear to be a burrower. Feeding
on small insects and worms, it does not generally venture forth from its lurking-
places till four or five o'clock in the afternoon, and retires before night. In
common with the other members of its genus, it differs from the majority of its
family in laying eggs.

While both the genera above-mentioned belong to a group
characterised by the palatine bones meeting in the middle of the
palate, the true skinks indicate a second and smaller group in which those bones



True Skinks.




COMMON SKINK (f nat. size).

are separated from one another. Skinks are neatly made, somewhat short-tailed
lizards, \vith short limbs provided with five toes serrated on their sides. The
tail is conical, the head and snout wedge-shaped, the ear more or less concealed,
while the nostrils are pierced between an upper and a lower nasal shield. Of
the nine species of the genus, which range from North Africa through Arabia
and Persia to Sind, the most familiar is the common skink (Scincus officinalis),
of the Sahara and Red Sea littoral. This species, which attains a length of
3 inches, has smooth, shining, rounded scales of great breadth, and is of a
yellowish or brownish colour above, with each scale marked by small brown
and whitish spots and streaks, and the sides of the body often ornamented
with dark transverse bands; the under-parts being uniformly whitish. Not
uncommon in Egypt, and abundant in the Algerian and Tunisian Sahara, the
common skink derives its specific name from having been extensively employed



170 LIZARDS.

in medicine as an infallible remedy for almost every disease under the sun ; its.
reputation as a healing agent still surviving among the Arabs, by whom the flesh
of the creature is used both as a drug and as an article of food. The exclusive
haunts of the skink are sandy districts, where it generally moves in a slow and
deliberate manner, and when frightened buries itself in the soil instead of
attempting to seek safety in flight. Indeed, the celerity with which the reptile
sinks into the sand is described as being little short of marvellous, suggesting the
idea of its escaping into some hole already existing rather than of excavating a
fresh burrow for itself, such a burrow not unfrequently extending to the depth of
several feet. During the daytime the skink, if quietly approached, may be
observed quietly reposing in the sun by the side of one of the small hillocks or
ridges raised in the sand at the base of trees by the wind ; and from such a state
of idleness it is only roused by the approach of a beetle or a fly, upon which it
darts with unerring aim. In spite of its strong teeth or claws, when captured, the
skink never makes any attempts to defend itself, beyond struggling vigorously.
Of its breeding-habits, little or nothing definite appears to be known. According
to Canon Tristram, the flesh of a few well-broiled skinks forms a dish not to be
despised even by a European palate.

Under the title of Challds, the ancient Greeks designated a
' remarkable snake-like lizard inhabiting Italy, Sardinia, and Sicily,
as well as Algeria and Tunis, which was known to the Romans by the name
of Seps; the latter being in allusion to the poisonous properties with which
this perfectly harmless reptile was supposed to be endowed. The " sops "
(Ckalcides tridactylus) is the typical representative of a genus of some twelve
species belonging to the present family, which exhibit a most interesting example
of the gradual degradation of limbs, some species having five toes to each foot,
while in others, as the figured example, the number of digits is reduced to three ;
and in one kind the limbs are represented merely by undivided rudiments.
The bronze lizards, as the members of the genus may be collectively termed,
belong to an assemblage of genera differing from all those already noticed in
that the nostrils are pierced either in or close to the terminal rostral shield of
the skull, instead of being more or less widely separated therefrom. In the case of
the present genus the nostrils are situated in notches cut in the hinder border of
the shield in question; while the body is greatly elongated, and the limbs are
either short or rudimental. The figured kind is one of two species with three-
toed limbs, and attains a length of 13^ inches, of which about half is occupied by
the tail. In colour it is olive or bronzy above, and may be either uniform, or
marked with an even number of darker and lighter longitudinal streaks. In the
south of France, Spain, and Portugal, it is replaced by the smaller striped bron/e
lizard (C. lineatus), in which the body is marked with nine or eleven longitudinal
stripes. The range of the whole genus embraces Southern Europe, Northern Africa,
and South-Western Asia, from Syria and Arabia to Sind.

The three -toed bronze lizard much resembles the blind -worm in general
appearance and habits, frequenting dam]) places, where abundance of its favourite
\\-nniis, snails, slugs, insects, and spiders are to be met with. Here it moves with a
wriggling serpentine motion similar to that of the blind-worm, which it likewise



CHAMELEONS.



171



resembles in producing living young and in retiring into a burrow for its winter
sleep. When not feeding, the creature, like most of its kind, delights to bask on
sandy spots in the full glare of the sun. The "seps" was believed to inflict deatli
on cattle by biting them during the night, its bite filling their veins with corrup-
tion ; and in consequence of this belief the unfortunate creature is still persecuted
with the same hatred as is the blind-worm in some parts of England.




Other Families.



THREE-TOED BRONZE LIZARD (liat. size).

The two remaining families (Anelytropidce and Dibamidcv) are
represented by worm-like burrowing lizards allied to the skinks (of
rhich they may be regarded as degraded types), but with no bony plates beneath
the scales, no external ear-openings, and eyes concealed beneath the skin. The
former family is represented by three genera, of which two are African, and the
third is from Mexico ; while of the latter there is but a single genus, with one
aecies from Papua, the Moluccas and Celebes, and a second from the Nicobars.



THE CHAMELEONS.
SUBORDER Rhiptoglossa.

With the skinks and their allies we took leave of the last of the reptiles which,
in the zoological sense, are included under the title of lizards, and we now come
to the second subordinal group, represented by those strange creatures known
as chamaeleons. From the lizards proper these reptiles are at once distinguished
by their worm-like extensile tongues, which arc club-shaped and viscous at the
extremity, and are capable of being protruded with the rapidity of lightning to a
distance of from four to six inches in front of the mouth. Hence the name of
worm-tongued lizards has been suggested for the group. Internally, the chameleons
differ from all lizards provided with well-developed limbs in having no collar-bones



172 CHAMELEONS.

(clavicles); while there are likewise certain distinctive features in connection with
the skull, into the consideration of which it will be unnecessary to enter in this
work. Another important feature by which these reptiles differ from lizards is
the structure of the feet, in which the toes are divided into two opposing branches,
thus forming grasping organs of great power. In the fore-foot the inner branch
of the foot includes three, and the outer two toes, in the hind-foot precisely the
reverse arrangement obtains; and from this peculiar hand-like structure of the
foot, which, by the way, recalls the feet of the parrots and many Picarian birds,
the chamaeleons have been spoken of as four-handed lizards. Yet another
peculiarity in the structure of these reptiles is presented by the eye, which is in
the form of a very large and prominent globe covered by a thick granular lid, in
the centre of which is a minute perforation for the pupil. The deliberate way in
which a chamaeleon rolls round one of these extraordinary eyes until it has focused
it on the fly about to be caught by the tongue is familiar to most of our readers.

The foregoing are the essential features by which the chameleons are dis-
tinguished from the lizards proper ; those remaining for mention not being such as
would be regarded by zoologists as of subordinal importance. Among these may be
noticed the triangular helmet-like form generally assumed by the hinder part of
the head, which often has three longitudinal ridges, connected together posteriorly
by a cross-ridge, all of which are ornamented with tubercles. The teeth, which are
small, triangular, and compressed, are placed on the summits of the jaws in the
acrodont fashion, none being present on the palate. The body is much compressed,
and the neck short ; the slender limbs are so much elongated as to raise the body
high above the ground in a manner different from ordinary lizards ; the tail is
long and prehensile, thus acting as a fifth hand; and in place of scales, the head
and body are covered with tubercles or shagreen-like granules. The larger species
attain a length of some 15 inches ; but the dwarf chamseleon of Madagascar
(Brookesia nanus) is less than 2 inches in length.

The chamseleons include close on fifty species, all of which are comprised in
the single family Cttamcvleontidce, and by far the greater majority in the typical
genus Chamceleon. Indeed, of the two aberrant genera, Brookesia is represented
by three species from Madagascar, while Rhampholeon comprises two tropical
African kinds. The true home of the group is Africa and Madagascar, together



Online LibraryRichard LydekkerThe new natural history (Volume 5) → online text (page 19 of 62)