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the only members of the family, save one other genus, which produce living
young; the number of young being in some instances as many as twenty-four.
Always small feeders, these lizards are capable of undergoing long fasts with
impunity ; and as they are habituated to a dry atmosphere, and probably never
drink, they may be sent packed in wadding long distances by post.

The most remarkable peculiarity connected with these lizards is their habit of
ejecting jets of blood from the eyes, apparently as a means of defence. The
following letter from Mr. V. Bailey, written from California, in 1891, describes the
phenomenon as first observed by him : " I caught a horned toad to-day that very
much surprised Dr. Fisher and myself by squirting blood from its eyes. It was
Ion smooth ground, and not in brush or weeds. I caught it with my hand, and
just got my fingers on its tail as it ran. On taking it in my hand, a little jet of
blood spurted from one eye, a distance of fifteen inches, and spattered on my
shoulder. Turning it over to examine the eye, another stream spurted from the
other eye. This he did four or five times from both eyes, until my hands, clothes,
and gun were sprinkled over with fine drops of bright red blood. I put it in a
bag, and carried it to camp, where, about four hours later, I showed it to Dr.
Fisher, when it spurted three more streams from its eyes." The phenomenon has
been subsequently observed in other specimens.

THE GIRDLED LIZARDS.
Family ZONUEIVJE.

Omitting mention of a family represented only by one genus (Xenosaurus) and
one species from Mexico, the next group for consideration is that of the girdled
lizards, from Tropical and South Africa, and Madagascar, of which there are four
genera. These lizards, which may be either snake-like in form, or provided with
four fully-developed limbs, differ from all those hitherto described, with the
exception of certain geckos, in having the temporal fossa3 of the skull roofed over



144



LIZARDS.






with bone ; while they are further characterised by a fold covered with small
scales running along the sides of the body and marking off the upper from the
under-parts. The tongue is simple, with its anterior moiety not extensile, and its
tip either rounded, or but slightly notched ; while there are well-developed eyelids,
and the drum of the ear is exposed. The back is either clothed with large shield-
like, and mostly keeled scales, arranged in well-marked transverse zones, or, more
rarely, with granules ; the head having large, regular shields. As regards their
teeth, these lizards conform to the pleurodont type, each tooth having its 1
widely open. Resembling in many respects the Iguanoids, from which they are
distinguished by the ossifications in the skull, these lizards also approach the
members of the next family, from which they differ by their simple tongues, the




CAPE GIRDLE-TAILED LI/ARD (liat. size.)

hollow bases of the teeth, and the structure of the bony plates underlying th>3<
scales, when such are present. In the South African snake-like genus (Ckamce-
saura), the fore-limbs are wanting, and the hind-pair rudimental, while the tail is
of extraordinary length. All the members of the family appear to be carnivorous.
Girdle-Tailed We take as our special example of this small family one of the-

Lizard. members of the South African girdle-tailed lixards (Zontn-n*), a
genus represented by seven species. These lizards differ from the other three-
genera in having the scales of the back underlain by bony plates of si in] do
structure ; and, resembling in appearance the rough-tailed lizard among the-
agamoids, they have a flattened triangular head, and a tail of modi-rate
li-ngth. On the upper surface the neck and back are covered with large <[iiad-
nmgular shield-like scales, while beneath there an- large flat- shields: the limbs
bearing keeled overlapping shields, and the tail being protected with whorls of



SNAKE-LIKE LIZARDS. I45

spinous scales. The teeth are small, and the rounded tongue is scarcely notched.
The figured species (Z. cordylus), which attains a length of rather less than 8
inches, generally has the back and tail of a dirty orange colour; the head and
IWt of a lighter yellow, and the urider-parts white ; although there are consider-
able variations from this normal coloration. All the members of the genus inhabit
rocky districts, and prefer those where there are ledges, upon which they run in
search of food or warmth. They are excellent climbers, and far from easy to catch,
often leaving their tails with their would-be captors.

THE SNAKE-LIKE LIZARDS.
Family



Nearly allied to the preceding family is a small group of lizards of variable
bodily form, typified by the common English blind- worm. Rigid in their bodies,
and having large symmetrical bony shields on the top of their heads, these lizards
resemble the girdle-lizards in the presence of bony plates beneath the overlapping
scales, and also in that the temporal fossa3 of the skull are roofed over with bone.
They differ, however, in that the bony plates beneath the scales are permeated by a
series of radiating or irregularly arranged canals ; and also in the conformation of
the tongue. The latter is composed of two distinct portions, namely, a thick basal
half, covered with villose papillae, and a smaller thin terminal moiety coated with
scale-like papillae, which is extensile, and capable of partial withdrawal into a sheath
formed by a transverse fold at the front of the basal half. As regards their denti-
tion, some forms have tubercular or conical teeth attached to the sides of the walls
of the jaws in the typical pleurodont manner; but in the blind- worms the teeth are
long, curved, loosely attached fangs, very like those of serpents. Instead of hollow-
ing out the bases of the old teeth, as in the preceding family, the new ones grow
up beneath them; and there may or may not be teeth on the bones of the palate.
Some of the members of the family agree with the preceding in having a longi-
tudinal fold along the sides of the body, while in others it is absent ; and there is
a similar variation in external form, some genera having fully developed five-toed
limbs, while in others all external traces of these appendages have disappeared. In
regard to the covering of the head, it should specially be noticed that there is a
large occipital shield at its hinder extremity. All the species differ from the
majority of lizards in changing their skin in a single piece, like most snakes.
With the exception of some species of the American genus Gerrhonotus, which
ascend low bushes, all these lizards live on the ground ; and the whole of them are

o '

i carnivorous, the larger species preying on reptiles and other vertebrates, and the
SHIM Her kinds on insects, spiders, slugs, and worms. While the blind-worms produce
living young, the others lay eggs. Containing seven genera and some forty-five
species, this family is most numerously represented in Central America and the
West Indies, a few species occurring in North and South America, two in Europe,
land one in the Himalaya and Burma; all the forms with functional limbs being
American. From limitations of space, our notice of the family will be confined to
two of the snake-like genera.
VOL. v. 10



146



U'/.ARDS.



Scheltopusiks.



The typical representative of this genus of .snake-like li/anls
<IJ>HH) was first discovered by Pallas in the wooded
valleys of the steppes bordering the Volga, where it is known, in common with
true snakes, by the name of scheltopusik, a term which may be conveniently
applied to all the members. The species was subsequently discovered in other
parts of Russia, as well as in Hungary, Istria, Dalmatia, Greece, Asia Minor, Syria,
Persia, Transcaucasia, Transylvania, and Turkestan, while it is replaced in Morocco
by a more brilliantly coloured variety. Four other species are also known, which
extend the range of the genus to North-Eastern India, Burma, and North America.
Agreeing with the American four-limbed genus Gerrhonotus in the presence of a
fold along the sides of the body, and the more or less conical teeth, the scheltopusiks
are distinguished by their moderately elongated snake-like form, and the absence
of functional limbs ; the European species alone having the hinder-pair represented

by minute rudiments on the
sides of the vent. These crea-
tures are covered with squared
scales, arranged in straight
longitudinal and transverse
series; and they are furnished
with teeth on the pterygoids,
and in certain cases on some
of the other bones of the palate.
The European species, which, in
addition to rudiments of hind-
limbs, is distinguished by an
aperture to the ear, attains a
length of rather more than a
yard, of which about two-thirds
are occupied by the tail. The
arrangement of the shields on .

the head is very much the same as in the blind- worm ; and the general colour is
brown, becoming lighter on the lower surface. The young are, however, olive-fl
grey, with wavy dark brown crossbands on the back, and bars on the sides of the,
head. Dwelling among the dense underwood of thickly - wooded valleys, the
scheltopusik harmonises so closely in colour with its surroundings, that it can j
only with difficulty be detected, as it glides away among the dead leaves and A
sticks at the approach of a footstep. Although as free from venom as ordinary
lizards, it is frequently mistaken for a snake, and then meets the fate which so
often, under similar circumstances, befalls the blind-worm. Preying largely upon j
mice and voles, and not even hesitating to attack and kill the deadly viper, the
scheltopusik is, however, a fierce and active creature, gliding swiftly and suddenly
upon its victims among the moss and leaves of the woods. It also subsists largely
upon snails; and is further reported to eat the eggs and young of birds. Its eggs
are laid under thick bushes and leaves. The scheltopusik is believed to be a
long-lived animal, the natives of the countries it inhabits stating that its full
period of existence is from forty to sixty years. Fossil scheltopusiks occur in




COMMON SCHELTOPUSIK.



Blind-Worm.



SNAKE-LIKE LIZARDS. 147

the Miocene deposits of Germany, some of which belong to an extinct genus
(Propseudopus).

The want of a lateral fold along the body distinguishes the
blind-worm, or slow-worm (Anguis fragilis), in common with the
remaining members of the family, from the scheltopusiks ; the blind- worm being
further distinguished from the other genera devoid of this fold by the absence of
all external trace of limbs, and the fang-like form of its cheek-teeth. The
appearance of the blind- worm, which, by the way, is the sole representative of its
genus, is so well known as not to call for much description. It may be observed,
however, that the scales are rounded in form, and arranged on the back in a
quincuncial pattern, while on the sides they are disposed in transverse rows; the




THE BLIND- WORM (3 licit, size).

ears are usually covered with integument ; and the palate is toothless. Attaining
a length of from 10 to 12, or even 14, inches, of which at least half is occupied
by the tail, the blind-worm is of almost equal thickness throughout, although
tapering slightly at the tail. The head is short and small ; the eyes, although
minute, are bright and piercing ; and the tongue is but slightly notched. In
the immature state the upper-parts are silvery, with a dark line down the middle
of the back, while the sides and under-parts are blackish. The markings, however,
often disappear in the adult, or may be replaced by dark dots, the upper surface
becoming at the same time brown or bronzy. The range of the species includes
Europe, Western Asia, and Algeria.

Gentle and inoffensive in its habits, and rarely attempting to bite even when
rudely handled, the blind-worm is commonly regarded as one of the most noxious
of reptiles. When captured, it usually contracts its muscles so forcibly as to



148 LIZARDS.

become perfectly rigid, in which state it easily breaks if bent or struck, thus giving
origin to its Latin name. Generally frequenting woods, heaths, and commons, the
blind-worm is one of the hardiest of British reptiles, making its appearance in the
spring at an earlier date than any other kind. According to Bell, " it retires in
the autumn under masses of decayed wood or leaves, or into soft, dry soil, where it
is covered with heath or brushwood, and penetrates to a considerable depth in such
situations by means of its smooth, rounded muzzle and polished body." It feeds
chiefly upon slugs, supplemented by various insects and worms. In June or July
the female produces from seven to twelve or thirteen living young, which are
active almost immediately after birth, and soon learn to feed by themselves. Like
other viviparous reptiles, the female is much given to basking in the sun during
the period of pregnancy, in order that its heat may aid in developing the eggs
contained in her body.

THE POISONOUS LIZARDS.
Family HELODERMATID^E.

Two conspicuously coloured lizards, ranging from the isthmus of Tehuantepec
in Central America as far north as New Mexico and Arizona, stand alone in the sub-
order in being poisonous, their bite, in certain cases at least, being sufficiently severe
to produce very serious symptoms even on human beings, while smaller animals
are soon killed thereby. These two species are the Mexican poisonous lizard
(Helodenna horridum) of Western Mexico, and the Arizona poisonous lizard (H.
suspectum) from New Mexico and Arizona; the former being known in its native
country by the name of silatica. Nearly allied to the blind -worm, which they
resemble in the general structure of their tongue and teeth, although distinguished
by certain peculiarities in the conformation of the skull, and by the upper surface
being covered with small granular tubercles, externally they are characterised by
the depressed head, the plump, rounded body, the tolerably long cylindrical tail,
the rather short limbs, in which the third and fourth toes are longer than the
others, the exposed drum of the ear, and the transverse arrangement of the rows
of tubercles on the upper surface. The curved and fang-like teeth are but loosely
attached to the jaws, and have grooves in front and behind for the transmission
of the poison ; while there are also teeth on the palate. Beneath, the body and
are covered with squared scales. In length, the figured species measures ra
less than 20 inches, while the other is somewhat larger. The former has a yellowis
or orange ground-colour, marked with a dark network on the head and body, and
with blackish rings on the tail. Among the reddish sand, intermixed with dark
pebbles, in which these lizards delight to nestle, this coloration, coupled with the
granular nature of the skin, appears to be protective.

Inhabiting dry regions from the western side of the Cordillera to the Pacific,
and apparently never entering water, the poisonous lizards arc nocturnal in their
habits, lying during the day hidden among the vegetation in a listless state, and
issuing forth at evening. Their movements are at all times deliberate: and as
these lizards are most commonly met with in the wet season, being but seldom
seen during the dry months from November to June, it is probable that they are




MONITORS.



149



torpid during part of the latter period. Their food comprises insects, worms,
myriapods, and small frogs, as well as the eggs of iguanas. Regarding the effects
of their bite, Sir J. Fayrer writes that he once saw two guinea-pigs bitten by
one of these lizards. " The bites were viciously inflicted, and the lizard did not
really relinquish its hold. Blood was drawn, the teeth being deeply inserted.
Both guinea-pigs were affected; the bitten limb was dragged, and appeared
partially paralysed. There were twitchings of the body generally; but these may
not have been due to the poison, but to agitation and fear." Both the unfortunate
rodents died in the course of the day. Another of these lizards once bit its




nat. Size).

owner, who was incautiously handling it, with very severe effects, which did not,
however, prove fatal. The poison is secreted in special glands situated near the
roots of the teeth.

THE MONITORS.
Family VARANID^E.

No better instance of the essential difference in the distribution of lizards as
compared with tortoises is afforded than by those lizards commonly known as
monitors. The tortoises of Australia, as we have already seen, belong to a different
suborder from those of India, while there are no genera common to Australia and
Africa. The monitors, all of which are included in the single genus Varanus, are,



150 LIZARDS.

however, common to the three countries named, while one species actually ranges
from India to Australia. That this widespread generic distribution is not a feature
of the present epoch is proved by the occurrence of fossil monitors in both the two
latter countries; whereas we have no evidence that they possessed genera of tortoises
in common. Before proceeding further, it is well to mention that the Egyptian
representative of the group is known to the natives by the name of ouaran, which
appears to be the Arabic term for lizards in general. Transliterated as warn/?, this
word has been confused with the German warnen, to warn, whence these reptiles
have been termed wam-eidecksen, or warning lizards ; this, again, having been
translated into monitors a name which, however erroneous in origin, is too well
established to be superseded.

The monitors are distinguished from all the lizards hitherto described by the
long and deeply-forked tongue, which is capable of being protruded far in front of
the lips, and is furnished at the base with a sheath, into which it can be withdrawn,
as in snakes. Including the largest members of the suborder, monitors are further
characterised by the long body, the broad, uncrested back, the well-developed, five-
toed limbs, and the long tail, which is very frequently markedly compressed. The
head is covered with small polygonal scales ; the eyelids are well developed ; the
opening of the ear is distinct ; and the head is covered with small scales. In the
skull we may notice alike the absence of a bony roof over the temporal fossae, and
of teeth on the palate ; while it is further remarkable for the union of the two
nasal bones into a single ossification. The teeth are large and pointed, with ex-
panded bases fixed to the sides of the jaws. On the back the scales are rounded
and bordered by rings of minute granules, so that they do not overlap ; while in
the under surface we find the squared scales arranged in cross rows. Pores are
absent both on the under surface of the thigh and in front of the vent. A peculiarity
of the group is the presence of an imperfect midriff, found elsewhere among reptiles
alone in the crocodiles. Monitors inhabit Africa, Southern Asia, Oceania, Papua,
and Australia, and are represented by nearly thirty living species, the largest of
which attains a length a little short of 7 feet. A fossil species from Northern India
was, however, probably 12 feet long, while one from Australia could not have fallen
much, if at all, short of 30 feet. The group is an isolated one, without near relation-
ship to any other family.

The genus may be divided into four distinct sections, the first of which is
represented solely by the desert-monitor ( V. griseus) of North-Western Africa and
South- Western Asia, extending from Arabia and the Caspian to North- Western
India. This species differs from all the rest in that the nostrils are in the form of
oblique slits, while the tail, except sometimes near its tip, is cylindrical. Attaining
a length of 4 feet 2 inches, and inhabiting the deserts of North- Western India, and
thence westwards through Southern Asia to the Caspian and North Africa, it takes
its name from its greyish yellow colour, which may be relieved by brown crossbars
on the back and tail, and streaks of the same hue along the sides of the neck ; the
young always having yellow spots and dark bars. In accordance with its sombre
coloration, this species is an inhabitant of sandy deserts. A far handsomer lizard
than the last is the Cape monitor ( V. <ill>i<iiilriii) of Southern and South- Kast em
Africa, where it is commonly known to the Hoers as the ' adder." It is the first



MONITORS. 151

representative of the second group of the genus, in which, while the nostrils are in
the form of oblique slits, the tail is compressed and keeled. Belonging to a sub-
group characterised by the smooth scales of the abdomen, it is further distinguished
by the absence of large (supraocular) scales above the eyes, by the nostril being
three times as far from the snout as from the eye, and by the small size of the
scales. It is slightly inferior in size to the last, and has the upper-parts greyish
brown, banded and spotted with yellow, and the under-parts yellowish. It




CAPE MONITOR ( nat. size).



generally frequents cliffs, or low rocky hills, in the interstices of which it delights
to hide, coming out to bask on the flat surfaces. Gray's monitor ( V. grayi) is an
example of a second subgroup in which the abdominal scales are keeled. In the
third great group, of which we take as our first example the water-monitor (V.
salvator), represented in the coloured Plate, round or oval nostrils are accompanied
by a compressed tail. In the species in question there is a series of transversely
elongated scales above the eyes, the oval nostril is situated as far from the eye as
from the tip of the snout, there are more than eighty transverse rows of scales be-



1 52 LIZARDS.

tween the fold 011 the throat and the groin, and the scales on the nape are not
larger than those of the back. This tine species, which ranges from India through
the Malayan region and China to Australia, attains a length of nearly 7 feet, and
is the largest of the genus. In colour it is dark brown or blackish above, with
yellow rings: the snout being generally lighter, with transverse black bars, and a
dark band, bordered by a yellow one, running backwards from the eye; the under
surface being uniformly yellow. The water-monitor frequents marshy localities,
being often found on trees overhanging rivers, and taking readily to the water,
either fresh or salt. The last species that we notice is the well-known Nile
monitor (V. niloticus), whose range extends all over Africa except a portion of the
north-western regions. Belonging to the same great group as the last, it represents
a second subgroup distinguished by the equality in the size of the scales above
the eyes ; while it is distinguished from its allies by the nostril being rather nearer
the tip of the eye than the snout. In size it is somewhat larger than the desert
monitor. The colour of the adult is brownish or greenish grey, with darker
reticulate markings, and more or less distinct yellowish rye-like spots on the back
and limbs; while beneath it is yellowish, crossed by some dark bands. This
species is likewise found in the neighbourhood of water, generally building itself
a nest among the bushes on the banks, especially of those streams that dry up in
the hot season. The Papuan monitor (V. y/m.smu.s) of New Guinea and the islands
of Torres Straits, may be cited as an example of the fourth group of the genus,
in which, while the nostrils are round, the tail is nearly or <|iiite cylindrical

As will be gathered from the foregoing, the monitors present
considerable diversity of habitat, although the majority prefer
the neighbourhood of water. The Papuan species is, however, believed to be
arboreal. All are carnivorous in their diet, feeding on frogs, snakes, the smaller
mammals and birds, as well as the eggs of both birds and reptiles, especially
crocodiles. Their movements are extremely rapid, both on land and in water;
and many a sportsman in his first day's snipe-shooting in the rice-fields around
Calcutta has been startled by the sudden rush of the common Indian species
(V. bengalensis) as it darts among the herbage close to his feet. Those species in
which the tail is the most compressed are the best swimmers; this appendage
serving as a powerful propeller in the water, and being also used as a weapon of
offence on land. In order to enable them to remain under water for some time, the
nostrils are expanded into large cavities within the snout; and when the apertures
are closed these pouches serve as reservoirs of air. Writing of the great water-



Online LibraryRichard LydekkerThe new natural history (Volume 5) → online text (page 17 of 62)