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do not prey upon other reptiles. Gentle and harmless themselves, these snakes are
often attacked and killed by craits and other venomous members of their own tribe.
On account of the well-known European smooth snake (Coronella
loevis) being included among them, we mention as a second genus of
this group the sling-snakes, of which there are about twenty known species ranging
over Europe, Western Asia, Africa, and America, while one (G. brachyura) occurs in
India. They belong to a group of genera in which the whole of the lower teeth are
learly equal in length ; while they are specially distinguished by the presence of
rom twelve to twenty teeth in the hinder upper jawbone, which increase in size
)wards the back of the series. The head is short, and scarcely distinct from the
leek ; the eye being rather small, with a round pupil, and the head-shields normal,
e body is cylindrical, and covered with smooth scales arranged in from fifteen
twenty-five rows, and furnished with pits at their tips ; the tail is of moderate
.'ngth ; and whereas the shields on the inferior aspect of the body are rounded,
lose beneath the tail are arranged in a double series.

The smooth snake, which attains a length of about 25 inches, is very variable
coloration, but the ground-colour of the upper-parts is generally brown. The
lost distinctive features are a large dark spot on the neck, often extending into
stripe, and two rows of dark brown spots arranged in pairs, and running down
the body ; there is also a dark stripe passing through the eye and the side of the
neck, while the under-parts are either steely blue, or reddish yellow and white, in
some cases spotted with black. This snake is found over the greater part of
Europe, and is occasionally met with in some of the southern counties of England.
Although now and then found in damp or swampy localities, it frequents dry stony
places where there is plenty of sunshine, resorting sometimes to old stone bridges
and heaps of building material. Like its congeners, this snake is chiefly terrestrial
in its habits; in disposition it is fierce, and its prey consists of other snakes and
lizards. In the end of August or beginning of September the smooth-snake lays
from three to thirteen eggs, which are so far developed that the included young
almost immediately break the shells and escape.



206



SNAKES.



Fierce Snakes.



Nearly allied to the preceding are the ophidians which (from
their German name zornschlangen) we may term fierce snakes ; these
demanding special notice on account of their having several representatives in
Southern Europe. From the preceding genus they may be distinguished by the
more slender form of the body, and the presence on the head of one or more sub-
oculars below the preocular shield ; while the arrangement of the longitudinal rows
of scales in odd numbers differentiates them from an allied genus. The number of
teeth in the hinder upper jawbone varies from twelve to twenty; the head is long
and distinct from the neck, with the eye of moderate size or large, and its pupil




THE DARK GREEN SNAKE (} nat. size).

round. The body is elongated and cylindrical, with the smooth or slightly keeled
and pitted scales arranged in from fifteen to thirty-one rows. On the lower surface
of the body the shields are rounded, or obtusely keeled on the sides; and the long
tail has two inferior rows of shields. The fierce snakes are represented by some
twenty species, ranging over Europe, Asia, and Northern Africa ; several of them
occurring on the Continent, although none are met with in the British Islands.
Their headquarters may be considered to be the countries surrounding the Mediter-
ranean basin. Deriving their name from the fierce and bold demeanour of the
majority of their representatives, these snakes are terrestrial or partially arboreal
in their habits, and feed chiefly on small mammals and birds. Of the European
forms, a well-known example is the dark green snake (Zatnenia



COLUBRINE GROUP. 207

inhabiting Hungary and the Mediterranean countries, and extending as far north
as the south of Switzerland ; while in the east it is represented by a variety known
as the Balkan snake, which attains a larger size than the typical form. These
snakes are distinguished from their allies by the regular arrangement of the shields
on the head, and the presence of two preorbital shields, of which the lower is small
and placed in the line of the labials ; and they are further characterised by the
relative shortness of the tail, which scarcely reaches a fourth of the total length.
The smooth scales are arranged in from seventeen to nineteen rows. The ordinary
form may attain a length of about 4 feet, but is generally smaller. In ground-
colour the head and nape are greyish yellow, the back and tail greenish, and the
under-parts yellow, upon them being black markings, which, while irregular above,
form regular oblique bars inferiorly, and in the hinder part of the body are
arranged in longitudinal stripes which continue to the end of the tail. In some
specimens, however, the ground-colour of the upper-parts is a beautiful yellowish
green, while on the lower surface it is canary-yellow ; in a third variety the whole
upper surface is uniform olive-brown, and in some cases it is completely black, the
under surface of the body being grey, with a steely blue lustre on the sides and the
whole of the under-parts. This snake is very abundant in Italy, and may be met
with in most gardens in the neighbourhood of Rome. Its habits vary to a certain
extent according to locality; and while in the Russian steppes it frequents the
hottest and driest spots, in Dalmatia and the Tyrol it is found in sunny, although
by no means dry situations, either in woods or among old buildings.

The other European species is the horseshoe snake (Z. hippo-
Horseshoe Snake. . .

crepis), common both to Southern Europe and Northern Africa, and

^presented in the lower figure of the illustration on p. 208. From its allies it
distinguished by the presence of a series of small suborbital shields beneath
the eye, which completely separate it from the upper labials, by the divided
anal shields, the presence of from twenty-five to twenty-nine longitudinal rows of
scales on the body, and likewise by the constancy of the coloration. Measuring
nearly 6 feet in length, this handsome snake has the ground-colour of the upper-
parts varying from greenish or greyish yellow through orange to reddish brown.
As a rule, the head is marked by a dark oblique band between the eyes, behind
which is a second band, convex in front, and reaching to the neck, and a third
marked with light spots, so that a horseshoe pattern is formed between the spots
and bands. On the back runs a row of yellow-edged dark oval patches, which
tend to unite towards the hinder extremity ; and on each side of this are a series
of smaller spots, beneath which, again, are more upright dark marks, extending
downwards to the lower surface. As the upper dark patches are very large, the
ground-colour is generally reduced to a series of rings, forming a very regular and
pretty pattern. The under-parts are yellow or orange-red, spotted with black.

Here also must be mentioned the Indian rat-snake (Z. mucosus),
now included in this genus, although formerly referred to the next.
It is a large species, attaining a length of 6 feet or more. In colour it is brown
above, frequently with more or less distinctly defined black crossbands on the
hinder-part of the body and tail ; the under surface being yellowish, often with
black edges to the shields of the hinder-part of the body and tail. The range of



208



SNAKES.



this well-known species extends from India to Java. Common everywhere in
India, and feeding on mammals, birds, and frogs, the rat-snake derives its name
from its habit of entering houses in search of rats and mice. Like its allies, it is
fierce and always ready to bite ; and old specimens brought to Europe never become
tame. When irritated, it utters a peculiar sound, which has been compared to that
produced by gently striking a tuning-fork. A smaller allied Indian species (Z.
corrus) differs by having the scales arranged in fifteen, instead of seventeen rows.

Nearly allied to the preceding are the American running snakes,
'of which the pantherine snake (Ptyas pantherinus) is a familiar
and handsome example. From the last genus the running snakes are chiefly



Running Snakes.




BLACK-MARKED AND HORSESHOE SNAKES (J liat. size).

distinguished by their teeth and the larger size of the eyes. They are all large
and powerful reptiles, with cylindrical body, clearly defined head, large eves,
regularly tapering tail, which is at least equal to a fourth of the total length, the
scales smooth and arranged in from fifteen to seventeen rows, normally-arranged
head-shields, unkeeled inferior shields, and about twenty-one equal-sized teeth in
the hinder upper jawbone. The pantherine snake, .which is an inhabitant of the
hottest regions of the Guianas and Eastern Brazil, and is especially common in the
neighbourhood of Rio de Janeiro, is characterised by having fifteen rows of scales
on the body, the lack of the small lower prenrbital shield, and its general form and
coloration; its length being as much as 7 feet. The ground-colour is yellowish
grey on the upper-parts; on the front of the head are three dark crossbars, while
two broad longitudinal stripes run along the hinder part of the head and neck :



COLUBRINE GROUP. 209

tlio ornamentation of the back takes the form of a row of large greyish brown
black-edged spots, which are lozenge-shaped on the neck, but further back become
irregular, and confluent with two lateral rows of spots. The yellowish white
shields of the edges of the jaws have black lines of division, and behind each eye
a blackish brown streak runs to the angle of the mouth. This snake frequents
swampy situations well covered with trees and bushes, and is remarkably swift
and active in its movements. In its general habits it appears to resemble the
ringed snake, feeding almost entirely on frogs and fish.

The typical representatives of the family are the climbing snakes,
Climbing Snakes. , . , , .

or which there are a large number or species, distributed over the

great part of Europe, Asia, and North and Tropical America. Agreeing with the
preceding genus in having the teeth in the hinder upper jawbone of nearly equal
size, the climbing snakes have from twelve to twenty-two of these teeth, the
teeth of the lower jaw being likewise subequal ; and they are further specially
distinguished by having the scales of the body arranged in from fifteen to thirty-
five longitudinal rows, and furnished with pits at their extremities, those in the
middle line of the back not being larger than the others. The long head is well
defined from the neck, with a moderate-sized eye, of which the pupil is circular,
and the shields normally arranged ; the elongated body is slightly compressed, with
its scales either smooth or keeled ; and whereas the shields on the lower surface of the
body usually have a more or less well-marked keel on the side, those of the tail
are arranged in a double row. All these snakes are fierce in their disposition, and
while all can climb well, some are almost entirely arboreal; others again, frequent
the neighbourhood of water, and are good swimmers. The food of all consists of
small mammals and birds. Formerly the chain-snake (Coronella getula}, of the
United States, common in the neighbourhood of New York, and attaining a length
of about 5 feet, was included in this genus, but is now referred to Coronella. The
dark ground-colour, which varies in tint from reddish brown to blackish brown and
fen black, shows on the upper surface a number of yellow crossbands, which on
bhe lower part of the sides unite with similar longitudinal stripes, and thus form a
regular light-coloured chain extending to the very tip of the tail. The shields on
the top of the head are deep chocolate-brown, with a few yellow spots ; the labial
shields are dusky or yellowish white, bordered with blackish brown, and the under-
parts dirty yellowish white marbled with brown.

Among the European representatives of the genus, the yellow, or yEsculapian
snake (Coluber longissimus) is recognised by the small head, imperfectly distinguished
from the neck, and rounded at the muzzle, as well as by the stout body, rounded tail,
and the nature of the scaling. On the head there is no small preorbital shield, and
of the eight upper labials the fourth and fifth enter the circle of the eye ; the body
has from twenty-one to twenty-three rows of smooth scales, and the anal shield is
divided. Generally, the upper surface is brownish yellow, with a tinge of grey,
and the lower aspect whitish, the hinder-part of the head having a yellow spot ;
while the back and sides are marked with small whitish dots, which in some places
are very distinctly defined, and assume the form of the letter X. There is, however,
great individual variation in colour, and a dark and a light variety may be
recognised. In the south of Europe, where it attains a length of about 4 feet,

VOL. V. 14



2 io SNAKES.

tliis snake prefers rocky, or at least stony districts abundantly covered with
bushes; but in Schlangenbad, the only German locality where it is found in
any numbers, old walls are its favourite resorts. As it feeds chiefly on voles
and mice, it is a decided benefactor to the agriculturist and gardener. It also
consumes, however, a certain number of lizards, as well as such birds as it can
contrive to capture, and occasionally plunders a nest and sucks the eggs. It is




^SCULAPIAN SNAKE (\ Hilt, size.)

very fond of climbing bushes, and low boughs or stumps of trees, as represented
in our illustration ; and in thick forests w r ill go from bough to bough, and then
from tree to tree without descending to the ground. Indeed, it is such an adept in
climbing, that it frequently captures swift-running lizards on the stems of trees.

Another South European species is the four-lined, or leopard-snake (C. leopar-
dinus). Remarkable for the beauty of its coloration, which, however, is subject to
great individual variation, this snake attains a length of about a yard, and differs
from all its congeners in the absence of a lower preocular shield on the head, and the



COLUBRINE GROU2 3 .



211



presence of eight upper labial shields, of which the fourth and fifth enter the circle
of the eye. There are from twenty-five to twenty-seven longitudinal rows of
scales in the thickest part of the body, and the anal shield is divided. Of the
numerous variations, there are two which are most constant, the first being the
typical but rare four-lined race. In this form the ground-colour is brownish grey,
upon which are usually four black longitudinal stripes, here and there interrupted ;
although these are sometimes replaced by two dark or blood-red lines. On the
sides are small blackish spots ; the under surface of the head and forepart of the
body is either yellowish white or bright yellow, but each under-shield is marked
with four or five irregular blackish spots, which become so large posteriorly that
the whole surface appears steel-blue, the yellow only showing on the edges of the
shields. In the second variety, or leopard- snake, the ground-colour is mahogany-




LEOFARD-SNAKE.



3d, mottled on the upper surface with blood-red black-edged spots, which may
either be arranged in two rows, or coalesce into transverse bands ; while on each
side there is a row of smaller, blackish, crescentic spots alternating with those of
the back. The range of this species is bounded to the west by the mountains of
Southern Italy and Sicily, and to the east by Asia ; both varieties occurring to-
gether in most districts between these limits, although in Greece and Dalmatia only
the leopard-snake is known.

Among the largest of European ophidians is the four- rayed snake (C. quatuor-
radiatus), which attains a length of between 6 and 7 feet, and is of an olive-brown
or flesh-coloured hue above, often marked with a pair of longitudinal blackish
brown stripes, a black line running from the eye to the mouth, and the under-
parts being straw-yellow. There are, however, many variations from this typical
coloration ; some specimens being entirely black, while the young generally have
black crossbands on the head, three rows of large brown spots on the back, the



212



SNAKES.



sides likewise spotted, and the under-parts with a blackish steel-grey tinge. The
distinctive specific characters are the presence of a small preorbital shield on the
head ; the arrangement of the scales of the middle of the body in from twenty-three
to twenty-five longitudinal rows these scales being smooth in the young but
strongly keeled in the adult and the divided anal shield. The distributional area of
this snake includes the whole of Southern and South-Eastern Europe, from Lower
Italy and Dalmatia to Turkey, as well as Greece and the adjacent islands, and extends
to the interior of Asia Minor ; but there is some doubt whether the species occurs
in the Caucasian region. All observers are in accord that the four-rayed snake




FOUR-RAYED SNAKE (J nat. size).

is not only harmless but useful, since it destroys rats, mice, voles, and smaller
snakes. It also preys upon moles, lizards, and small birds.

Black-Marked Another European species of the family is the black-marked

snake. snake (Coluber scalaris), which belongs to a separate group charac-
terised by the following features. The rostral shield of the head is of a large
convex, and pointed in front, while it extends backwards between the prefroni
shields, where it terminates in a point. The tail is relatively shorter than in the
typical group. The black-marked snake, formerly separated as Rhinechis,
and represented in the upper figure of the illustration on p. 208 has the
cylindrical body relatively thick, the tail short and blunted, and the flattened head
broad behind and sharp in front. The body-scales, which are arranged in from
twenty-five to twenty-nine rows, are long, four-sided, and smooth ; the shields on
the under surface of the body are bent at the edges; while those beneath the tail form
a double series. As regards colour, there is much variation ; the ground-colour
varying from bright grey or greenish grey, through reddish or yellowish brown, to
olive or reddish yellow ; while the markings of the head often take the form of a



CO LU BRINE GROUP.



213



perpendicular black streak through the eye, and another from the eye to the mouth:
the neck having a dark crossband, and a row of similar spots running down the
back, beneath which are another series of smaller ones, followed inferiorly by a
third and fourth row. With age these spots tend gradually to disappear, till finally
there remain only two dark brown or blackish rows running from the neck to the
tip of the tail. In length this snake measures rather more than 4 feet. Every-
where rare, the black -marked snake seems to be confined to Spain and the opposite
parts of Africa. While resembling the climbing snakes in the general nature of
its food, it also preys upon grasshoppers ; and it will follow voles and mice into
their burrows. A good climber, it is stated to be more rapid in its movements
than any other of the European snakes ; and its keenness of vision is remarkable.




Wood-Snakes.



SIPO, OH BRAZILIAN WOOD-SNAKE (J nat. size).

Whereas the preceding members of the family only climb trees in
search of food the American wood-snakes are purely arboreal forms,
especially adapted by their coloration to such a mode of life. Although they
resemble the climbing snakes in possessing equal-sized solid teeth, they differ in the
larger eye, which may be of very great size, their distinctly compressed and more
slender body, and the small number of its longitudinal rows of scales, which does
not exceed from ten to twelve. The five known species are inhabitants of the West
Indies and the forest districts of Central and South America, all being characterised
by their more or less uniform olive-green coloration. In the forests of Brazil, the
Guianas and Venezuela, as well as in the Lesser Antilles, lives the sipo, or Brazilian



2i 4 SNAKES.

wood-snake (Herpetodryas carinatus), which we select as a well-known example of
the genus. Frequently attaining a length of about 7 feet, and remarkably beautiful
in coloration, this snake generally has the upper-parts of a bright verditer or olive-
green, shot with a tinge of brown on the back, while the under-parts are greenish
or bright yellow ; the greenish hue prevailing in the middle of the body, and the
yellow elsewhere. Throughout there is a shimmering play of colours of all shades
of green passing into metallic brown ; while the middle line of the back has a
brighter longitudinal streak, frequently bordered on each side by a darker band,
In the West Indies this species undergoes a remarkable change of hue, becoming
blackish brown or black above, with the under-parts steel-grey ; the upper lip and
edges of the jaws alone preserving the original yellowish green. The scales are
arranged in twelve rows, and are mostly smooth, although the two middle rows on
the back are keeled ; the eye being of very large size. Next to the coral-snake,
the sipo is the most abundant of Brazilian ophidians, and may be met with both
on sandy jungle-clad ground close to the shore at Rio de Janeiro and Cape Frio,
where specimens of upwards of 10 feet in length have been observed. In addition
to sandy localities it also frequents swampy spots near the sea. In its movements
it is so rapid that, when startled, it seems to disappear like a flash of lightning.
It feeds largely upon frogs, as well as upon lizards and young birds, and lays
only five eggs, which are remarkable for their cylindrical and slender form.

In the Old World and Australia the wood-snakes are replaced by
the solid-toothed tree-snakes, forming the genera Dendrophis and
Dendrelaphis ; both of which are distinguished from all the preceding types by
having the hinder border of each of the shields on the lower surface of the body
with a notch on each side, corresponding to a suture-like lateral keel ; the scales of
the body being arranged in from thirteen to fifteen rows. While in the first-named
of the two genera all the teeth in the hinder upper jawbone are approximately
equal in length, and the row of scales in the middle line of the back larger than the
others, in the second genus the foremost teeth in the hinder upper jawbone are
enlarged, but the middle row of scales on the back are similar to the rest. All
these snakes have large eyes, and elongated and often compressed bodies, and
their general coloration is some shade of green or olive, often witli a bronzy tinge ;
their habits being mostly arboreal. Of Dendropkis nine species are known,
ranging from India to Australia; while Dendrelaphis is represented by five species
ranging from India and the Malayan region to the Philippines.

Egg-Eating The last representative of the solid-toothed series of the Colubrines

Snake. i\\&,i we have space to mention is the curious little egg-eating snake
(Dasypeltis scabra), of South Africa, which represents a subfamily (Dasypdtvna )
by itself. The essential character of the subfamily is the rudimental condition <i'
the dentition, the front of both the lower jaw and upper jaws being devoid of teet
To compensate for this lack of ordinary teeth, the egg-eating snake is, howev
provided with a series of about thirty of what may be termed throat-teeth ; these
lieing the lower spines of the vertel.ne, which project into the u'soplmgns, and are
tipped with enamel. The scales are strongly keeled. This little snake is about a
couple of feet in length, and has a Ixxty not much thicker than a man's finger.
Although it lives in trees, and feeds on the eggs of small birds, it will when pressed



COLU BRINE GROUP.



215



by hunger descend to the ground and rob hens' nests. That such a tiny creature
should be able to swallow a lien's egg seems incredible, but nevertheless a specimen
has been taken with the egg actually within its jaws, and the whole head so
swollen as to render the mouth incapable of being closed; while an example
in the London Zoological Gardens swallowed pigeons' eggs without any apparent
difficulty. When swallowed, the egg is split longitudinally by the row of teeth in
the throat, and the whole of the contents secured. After being thus broken, the



Online LibraryRichard LydekkerThe new natural history (Volume 5) → online text (page 23 of 62)