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flesh, which is white and well-flavoured, and consequently much appreciated.

Thorny-Tailed Quite a different type of tail to that of the last is presented by

Lizards. {j ie thorny-tailed lizards, of which there are seven species, inhabiting

arid tracts in Northern Africa and South-Western Asia. From the whole of the

foregoing members of the present family, these lizards are sharply distinguished



AGAMOID GROUP.



by the circumstance that the front teeth, instead of being small and conical, are
large, and in the adult united together into one or two broad cutting -teeth,
separated from those of the cheek-series by a gap ; while externally they are easily
recognised by their short tails covered with well-defined rings of spiny scales. The
head is remarkably short and rounded ; the body, as in most terrestrial members



ARABIAN THORNY-TAILED LIZARD (\ nat. size).




of the family, is much depressed ; and there is no crest along the back. There are
no folds or pouches on the neck, but pores are present both in front of the vent
and on the thighs, and the aperture of the ear is exposed. The Arabian thorny-
tail, or dabb, as it is termed by the Arabs ( Uromastix spinipes), is one of the
best known members of the genus, and inhabits Egypt, Crete, and Arabia. It
belongs to a group characterised by the rings of spiny scales on the upper surface
of the tail being in juxtaposition; while, in common with two other species, it



126 LIZARDS.

is specially distinguished by the circumstance that two or more transverse rows
of scales on the lower surface of the tail correspond with one on its upper aspect.
The Arabian species, which attains a length of about 18 inches, differs from its
two nearest allies in the minute size of the scales covering the body, coupled with
the presence of a few scattered somewhat larger tubercular scales on the flanks.
Its colour is either sandy grey, or greenish above, which may be either uniform or
clouded with brown. The ornate thorny-tail (U. ornatus), of Egypt and Syria,
differs from the other three members of the first group in that the scales of the tail
form complete rings, those on the lower surface being as long as those on the upper.
With the exception of one species (U. microlepis) inhabiting Persia, the
members of the first group are confined to Africa, Arabia, and Syria, whereas
the three representatives of the second group are exclusively Asiatic, one (U.
loricatus) being from Persia, the second (U. asmussi) common to Persia and
Baluchistan, while the third (U. kardwickei) is an inhabitant of Baluchistan
and Northern India. In the whole of these three Asiatic species the rings
of spiny scales on the upper surface of the tail are separated from one
another by rows of smaller smooth scales. In the Indian thorny - tail the
spines on the tail are small, with the lateral ones the largest ; there are no
enlarged tubercular scales on the back ; and the front surface of the thigh
is marked by a large black spot. In size this species is much inferior to its
Arabian congener, not exceeding some 11 inches in length. Its colour is either
uniform sandy above, or the same spotted or mottled with a darker, and whitish
beneath, with the aforesaid dark mark on the thigh.

Conforming in their sombre coloration to the desert regions they
frequent, the thorny-tailed lizards are entirely vegetable-feeders, and
live in burrows, resembling those of the smaller foxes, which are excavated by
themselves. These burrows, which may be as much as 4 feet in length, sometimes
turn almost at right angles to their original course, at a depth of a foot or so from
the surface. Generally living solitary or in pairs, these lizards are met with
abundantly in parts of Eastern Persia and the Punjab, and when approached
once make for their holes. If they succeed in getting their fore-limbs witl
the aperture of their burrows, it is impossible to pull them out, for, as the
writer knows by experience, they will rather suffer their tails to be pulled from
their bodies than let go their hold. They are generally somewhat heavy am
deliberate in the movements, turning their heads from side to side while walkii
but are capable of running with tolerable speed. In the cold season, at any rat
they never leave their burrows till the sun is well up ; and while in Persia ami
India they are commonly found on half-desert gravelly plains scattered over with
low bush, the Arabian species is often met with in the clefts of rocks, whence it
issues forth to bask on the smooth slabs or boulders. According to Brehm, as
many as a dozen of these lizards may occasionally be seen on a single slab of rock.
All the species appear to be timid and gentle in their disposition, rarely, if ever.
attempting to bite when captured. Their food comprises leaves and flowers, dried
fruits, and the seeds of grass, as well as grass itself : but although in the wild state
they seem never to touch animal food, in captivity the Indian species will greedily
devour meal-worms. According to Arab reports, the dabb never by any char



AGAMOID GROUP. 127

drinks, even when water is at hand, and this statement has been confirmed by
modern observers. By the Arabs these lizards are frequently tamed and kept in
captivity; and their flesh, which resembles that of young chicken, is much
relished by them as an article of food. Nothing appears to be known as to their
breeding-habits. All the species thrive well in captivity in Europe. It is not
improbable, according to Canon Tristram, that the reptile mentioned in Leviticus
under the name of tortoise, is really the dabb.

East African ^wo nearly allied lizards from East Africa namely, Aporoscelis

Thorny-Tailed princeps from Zanzibar and Somaliland, and A. batilliferus from
Lizards. Somaliland, while resembling the members of the preceding genus
in general external characters, differ in the absence of true pores either on the under
surface of the body or on the thighs, and are consequently referred to a distinct
genus. Both appear to be rare, and are of comparatively small size, the first-
named measuring only about 7|- inches in length.

Even more strange and uncouth in appearance than the frilled
lizard, is another Australian species commonly known as the moloch
'oloch korridus), but termed by the settlers the spiny lizard or thorny devil.
This, the last remaining representative of the agamoids, differs from all the other
members of the family in being covered with large conical spines, and in the con-
formation of its mouth and teeth. In all the forms described above the mouth is
large and the teeth of both jaws are erect, but in the moloch the mouth is very small,
and the cheek-teeth of the upper jaw are placed horizontally, with their summits
directed inwardly. About 8 inches in total length, this extraordinary lizard has a
small head, with an extremely short snout, on the summit of which are pierced the
nostrils ; it has a much depressed body, a short and rounded tail, and thick, powerful
limbs armed with strong claws. On each side of the head immediately above the
small eye is a large horn curving outwards and backwards, while there is a smaller
conical spine above the nostril, a second behind the horn over the eye, a third and
larger one in front of each ear, as well as one on each side of the occiput. Between
these spines the upper surface of the head is protected by small granular tubercles ;
ile among the spines on the upper surface of the body, limbs, arid tail, are
similar granules intermingled with polygonal scales of which the edges are in
apposition. On the back the spines form ten or more longitudinal series, of which
the outermost are the largest. The lower surface of the body has a covering of
rough, and slightly overlapping scales, among which are numerous rounded and
keeled tubercles. In general colour the creature is yellowish, ornamented with
symmetrical chestnut or reddish brown markings defined by darker borders.

Inhabiting Southern and Western Australia, and being not uncommon in

several localities in the neighbourhood of Port Augusta, the moloch is found only

in districts where the soil is dry and sandy. Occasionally two or three may be

observed basking in company on the top of a sandhill ; and it is the frequent

habit of this lizard to bury itself in the sand to a small depth below the

surface. Its small eye and general manner indicate pretty clearly that the moloch

| is diurnal in its habits, although it may possibly occasionally move about during

: the night. Although generally very slow in its movements, it has been known,

when disturbed, to make for a neighbouring hole with considerable speed. In

!



U11CD'

",



128



LIZARDS.



repose it generally rests with the head so raised as to be on the level of the back.
Its chief food appears to be ants, although vegetable substances are sometimes
eaten. The female deposits her eggs in the sand. To a certain degree the inoloch
is endued with the power of changing its colour to harmonise with its surround-
ings, such changes taking place very gradually, although not uiifrequently. The
most general change is to a uniform sandy slate, or russet colour, when the
ornamental markings almost completely disappear. In spite of its ferocious and
somewhat forbidding appearance, the moloch is a perfectly harmless creature, its




MOLOCH LIZARD (nat. size).

formidable-looking armour being never used for attack. In captivity it is di
and sluggish, undergoing fasts of a month's duration without any apparent incc
venience.

THE IGUANOID LIZARDS.

Family lGUANIl>.i:.

The extensive family of lizards, of which the well-known iguanas of Sout
America and the West Indies are the typical representatives, may be regarded MS
occupying the same position in America as is filled by the agamoids in the warmer
parts of the Old World. Whereas, however, the agamoids are exclusively deni/ens
of the Eastern Hemisphere, the iguanoid li/ards are not absolutely confined to the




THE BLACK IGUANA.



IGUANOID GROUP. 129

western half of the globe, two genera occurring in Madagascar, and a third in
the Fiji and Friendly Islands. Although, with these exceptions, the family is
unknown in the Old World, the same perverseness which causes Anglo-Indians to
speak of the Oriental crocodiles as alligators, leads to the monitors of the Old
World being commonly termed iguanas, although few lizards are more unlike
than the members of these two groups, both as regards external and internal
characters. In their general structural features the iguanoids come very close to the
agamoids. Thus in both groups the head is covered with numerous small shields ;
while the back is clothed with scales of different kinds, which are often arranged
in oblique rows. Similarly, the eyes have round pupils and are furnished with
well-developed lids, and the drum of the ear is frequently exposed. Both groups,
again, have two pairs of limbs, which may be relatively longer or shorter in the
different genera, but are each provided with five toes. The length of the tail is
subject to a large amount of variation, although it generally exceeds that of the
head and body. Moreover, the two families resemble one another in the form and
structure of the tongue, which is thick, short, scarcely notched, and generally fixed
to the floor of the mouth throughout its length. When, however, we come to
contrast the teeth of iguanoids with those of agamoids, we find a striking difference
which at once serves to draw a sharp line of distinction between the two families.
As we have already seen, in the latter group the teeth are attached to the very
summits of the bones of the jaws (acrodont), and are commonly differentiated into
front teeth, tusks, and cheek-teeth. In the iguanoids, on the other hand, the tall
and cylindrical teeth are attached by their sides to the outer wall of the jaws in
the so-called pleurodont manner ; the whole series being generally more or less
uniform in character, and without any large projecting tusks. In the typical
anas the teeth have somewhat diamond-shaped compressed crowns with serrated

ges; and it was from a superficial resemblance to this type of tooth that the
teeth of the great dinosaurian reptile from the English Wealden received the name

Iguanodon. A few genera, again, have the teeth divided into three lobes, thus
resembling a fleur-de-lis. Many species of the family are further characterised by

(ving teeth on the pterygoid bones of the palate, while a single genus is one of
3 few lizards in which there are teeth on the palatine bones.
The iguanoids, which comprise about three hundred species, arranged in fifty
nera, may be regarded as especially characteristic of South and Central America,
;hough they extend into the warmer parts of the northern half of that continent,
ranging in the west as far as British Columbia, and in the east to Arkansas
and the Southern United States, while they are also represented in many of the
American islands. Their occurrence in Madagascar (where, as in America,
agamoids are wanting) has been already mentioned, and it is probable that this
remarkable instance of discontinuous distribution may be explained by the
occurrence of fossil remains of species of the family in the upper Eocene rocks
France, where agamoids seem likewise to have been wanting.

Very variable in external appearance, iguanoids present equal diversity in
their modes of life, and it is not a little curious that, with the exception of the
flying lizard, almost every group of the agamoids finds a parallel, both as regards
.ructure and habits, in the present family ; the two families being thus repre-
VOL. v. 9







130



LIZARDS.



sentative groups. There are, however, certain iguanoids, such as the anolis
lizards and the sea-lizards which have no representatives in the preceding family.
The majority of the iguanoids feed on insects, although some, like the true
iguanas and the sea-lizards, subsist on a vegetable diet, while one genus is stated
to be omnivorous. Only two genera are known to produce living young.

In the forests, groves, and gardens of all the warmer regions of
America live a number of beautiful lizards commonly known by the
name of anolis, which is applied in the Antilles to some members of the group.
The distinctive features of these lizards are the pyramidal form of the head, the
moderately long neck, the presence of a broad and generally brilliantly-coloured
appendage on the throat of the males, the slender body, which may be either com-



Anolis Lizards.




7



BED-THROATED ANOLIS (liat. size).



pressed, cylindrical, or slightly depressed, the relatively long hind-limbs, the large
feet, in which the toes are of very unequal length, and their middle joints expand'
with smooth transverse plates on the under surface, and the long, curved, and sha
claws, which are raised above the level of the expanded joints. The tail is long and
hard, although not prehensile ; the covering of very minute scales on the back and
tail is not unfrequently elevated to form a crest ; the cheek-teeth are characterised
by their distinctly tricuspid crowns ; and teeth are generally present on the pterygoid
bones of the palate. Lastly, these lizards possess the power of changing tin -\r
colour to even a greater extent than is the case with the chameleons. From
among more than one hundred species belonging to the genus we select for
illustration the red-throated anolis (Anolis carolinensis), which inhabits the
South-Eastern United States and Cuba, and presents the following distinctive
features. The head, which is long, triangular, and depressed, is nearly smooth in



IGUANOID GROUP. 131

the young, but in the adult has well-marked frontal ridges, and some large rough
shit 'Ids on the crown; and the appendage on the throat of the males is relatively
small. The body is not compressed, flat beneath, and not keeled above ; the scales
on its upper and lower surfaces being keeled and approaching an hexagonal
form, with their edges either in apposition or slightly overlapping. The tail is
cylindrical and tapering, with some slightly enlarged scales on its upper surface,
and nearly equal to twice the length of the head and body. In the living animal
the colour of the upper surface is brilliant metallic green, and that of the under-
parts silvery white ; the appendage on the throat of the males, which is covered
with white scales, is red ; there is a large blue eye-like spot above the axil of the
i'oiv-limb; and the region of the tail is ornamented with black markings. In
some specimens the green colour passes more or less distinctly into brownish or
brown ; and, when excited, the creature is able to change its general hue from
greenish grey, through dark grey and brown of all shades, to the ordinary metallic
gi-i't-n. In length this lizard varies from 5i to nearly 9 inches, according to sex;
fully two-thirds of these dimensions being taken up by the tail.

In Louisiana, Carolina, and Cuba, the red-throated anolis is one of the most
common of lizards, and may be noticed in all suitable spots, such as woods and
garden-hedges, as well as the exteriors, and sometimes also the interiors of
dwell ing-houses. Like their congeners, they are, however, to be met with most
abundantly in the deep woods, and then so closely do they assimilate to their
surroundings that their presence, when at rest on a bough, is generally only
;vealed by their brilliant eyes. In houses, these lizards exhibit but little fear of
ji, running about with the greatest unconcern in search of flies and other
sects; and as, in addition to gnats, flies, butterflies, beetles, and spiders, they kill
id eat wasps, scorpions, and other noxious creatures, their visits are encouraged,
motion throughout the day, they display extreme activity and speed, both when
Lilting among the foliage of trees or on the ground, pouncing upon their insect-
jy like a cat upon a mouse. In the spring, during the breeding-season, the
iles display great jealousy of one another, so much so, indeed, that when two
set, a combat is certain to ensue, and is often continued till one of the combatants
is lost its tail, which appears to be taken as an immediate sign of defeat. During
iese battles the appendage on the throat is inflated, and the changes of colour
more rapid than at any other time. With the advent of summer, these mutual
animosities are, however, forgotten, and these lizards dwell together in perfect
amity, sometimes collecting in large companies. The females of some of the species
arc stated to dig a hole for the reception of their few white eggs with their fore-
paws, at the foot of a tree or in some moist spot near a wall, afterwards carefully
covering them with soil to protect them from the sun's rays. The figured kind is,
however, said to be very . careless in regard to the place where its eggs are
deposited ; these being found either on bare sand or rocks, or even in rooms. The
red-throated anolis, like most of its kindred, can be readily tamed, and makes a
most charming pet, which can be without much difficulty transported to Europe.
Writing of a pair which were at one time in his possession, Bell says that " I was
in the habit of feeding them with flies and other insects, and having one day
placed in the cage with them a very large garden-spider, one of the lizards darted



1 32 LIZARDS.

at it, but seized it only by the leg. The spider instantly ran round and round the
creature's mouth, weaving a very thick web round both jaws, and then gave it a
very severe bite in the lip, just as this species of spider usually does with any
large insect it has taken. The lizard was greatly distressed, and I removed the
spider and rubbed off the web, the confinement of which appeared to give it great
annoyance; but in a few days it died, though previously in as perfect health as its
companion. The lizard was evidently unused to the wiles of the British spider."

The crested anolis (A. cuvieri), belonging to a small group, with compressed
and crested bodies and tails, is remarkable for the great extent to which the pouch
on the throat can be inflated, probably for the purpose of terrifying foes.

Two lizards, respectively from Jamaica and Colombia, differ
Allied Genera. L . , , ., .,

from all the species or true anolis in having prehensile tails, in

consequence of which they are referred to a distinct genus Xipliocercus. In a
third genus, Chamcdolis, the cheek-teeth have smooth and nearly spherical crowns.
The strange form of the members of the present genus of
iguanoids probably suggested to the earlier naturalists the imposition
of the name basilisk, a term which, as all our readers are doubtless aware,
originally denoted a fabulous snake-like reptile before whose deadly glance every
living being save the cock perished. Be this as it may, the reptiles now known
as basilisks are large, although perfectly harmless members of the present family,
belonging to a group distinguished from the preceding one by the absence of
dilatation of the toes, and the more or less marked backward prolongation of the
hinder portion of the head. In the presence of a large crest on the upper surface
of the tail, the basilisks recall the sail-tailed lizards in the again old group, of
which, indeed, they may be regarded as the representatives in the present family.
As a genus, they are characterised by the head in the adult males being produced
backwards into a large cartilaginous lobe ; by the compressed form of the body
and tail, which are covered with small overlapping scales ; and by the presence of
a crest on the back and tail in the males, such crests being always supported on
the back by the prolonged spines of the vertebras, and frequently also in the tail.
Although there is a transverse fold on the throat, the pouch characterising the
anolis lizards is wanting. The long limbs are covered with keeled scales ; and the
outer sides of the hind-toes have a much developed lobe of skin. The cheek-teeth
have three-cusped crowns ; and teeth are borne on the pterygoid bones. Internally,
the basilisks form an exception to the members of this and the two preceding
families in that the inner extremities of the collar-bones have a loop-like expan-
sion, as in the geckos; while they differ from the anolis lizards in the absence
of the false abdominal ribs so frequently present in this and the preceding families.
The basilisks are represented by four species from Tropical America, among
which the figured helmeted basilisk (Basiliscus am&ricanus) is the one most
commonly known. It is the largest representative of the genus, attaining a length
of about 31 inches, of which nearly three-quarters is taken up by the tail ; and is
one of two species characterised by the great height of the crest of the tail in
the males, which is supported by prolongations of the spines of the vertebrae.
Inhabiting Panama and Costa Rica, it is specially characterised by the undivided
head-crest of the males ; while the scales 011 the under surface of the body are



IGUANOID GROUP.



133



smooth. Tlio natural colour of the creature is probably green, although specimens
preserved in spirit are olive-brown above, and dirty white beneath. The back is
marked with more or less distinct blackish transverse bands, while a lightish
streak runs from the temple to the neck, and a more defined one from the region of
the eye to the fore-limb. The banded basilisk (B. vittatus), ranging from Mexico
and Ecuador, represents a second group of the genus, in which the tail-crest of the




HELMETEU BASILISK (-J liat. size).

males is low, and not supported by bony rays. In this species the scales of the
under surface of the body are keeled, whereas in the allied B. galeatus they are
smooth. In general appearance all the basilisks suggest the idea of lizards upon
whose backs has been grafted a fish's fin. As regards their habits, all the members
of the genus spend their time either on trees, or bushes, often basking in the sun on
fallen steins, and seldom, if ever, venturing far from the neighbourhood of water.
Most numerous in the vicinity of rivers, basilisks are, indeed, so common in
Guatemala, that the collector has 110 difficulty in obtaining as many specimens as



134 LIZARDS.

he may desire, although the rapidity of their movements is so great that sonic
practice is required to effect their capture. Their food is entirely of a vegetable
nature; and to gather this the basilisks are astir with the first rays of dawn,
while during the heat of the day they prefer to rest among the most leafy boughs.



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