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two halves of the shell, generally fitted into one another, are rejected.

The pale snakes, or, as they are called in Brazil, the moon-snakes,
may be taken as our first representatives of the second of the three
great parallel series into which the Colubrine family is divided. This back-fanged
series, or Opisthoglossa, is characterised by having one or more pairs of the hinder



Moon- Snakes.




CROWNED MOON-SNAKE ( liat. size).

upper teeth longitudinally grooved, aiul thus capable of acting as poison-fangs.
Many of these snakes are indeed extremely venomous, their bite being capable of
producing death in a few minutes. They are divided into two subfamilies, of which
the first, or Dipsadince, are characterised by the lateral position of the nostrils ;
and they are either terrestrial or arboreal in their habits, while their distribution
is world-wide.

Belonging to the first of the two subfamilies, the moon-snakes are characterised
by the slender and somewhat compressed form of the body ; the flattened head,
which is but imperfectly differentiated from the neck, is broad behind and narrow
in front, although somewhat pointed at the muzzle; while the upper jaw projects
considerably over the lower. The scales, moreover, are smooth ; both the anal
shield, and the shields on the lower surface of the tail are single ; and the eye,
as in most of the other members of the subfamily, has the pupil vertical. The



2l6



SNAKES.



few representatives of the moon-snakes are confined to South America; the
species here figured (Scytale coronatum) being an inhabitant of the eastern .side
of that continent. In size this snake is comparatively small, measuring only
about 2 feet in length; its distinctive characteristic being that on the hinder
portion of the body, or anterior part of the tail, the middle row of scales are not
greatly enlarged. In young individuals the ground-colour is red, with a dark
brown circular spot on the back of the head, another on the crown, and a ring on
the neck, behind which are smaller spots of the same colour. With age the colour
darkens, and the markings disappear, till in the adult the upper surface is black,
and the lower side white. Very common in the neighbourhood of Bahia, this
snake, like the other members of the subfamily, is almost exclusively nocturnal :
and its food consists solely of lizards. Although their fangs are large, it appears
that these reptiles never attack human beings.




Cat-Snake.



CAT-SNAKE ( nat. size).

As one of the few European representatives of the group under
consideration, reference may be made to the so-called cat-snake
(Tarbophis vivax), which is the sole member of its genus. It is characterised by
its spindle-shaped body, the clear distinction between the flattened head and the
neck, the relatively short tail, and the small size of the eyes. In place of a lower
preocular shield, the elongated loreal extends backwards to the eye, so as to conic
in contact with the upper preocular; tins arrangement bring unknown in any other
European snake. In the lower jaw the front teeth are much longer and more bent
than those which follow ; while the fangs in the hinder part of the upper jaw are
also elongated and much curved. Sometimes reaching a little over a yard in length
this snake is of a dirty brownish yellow or grey ground-colour, with small black



COLUBRINE GROUP, 217

dots and a chestnut-brown spot on the shields of the head, while the neck has a large
blackish or reddish brown patch, and rows of smaller spots of the same colour
ornament the back. There is also a dark band from the eye to the corner of the
mouth ; each side of the body has a row of small spots ; and the under-parts are
whitish with a brown marbling. The cat-snake ranges from the shores of the
Adriatic to the neighbourhood of the Black and Caspian Seas, and Africa as far south
as 45 N. It inhabits rocky and sunny spots, and feeds mainly if not exclusively
'on lizards. Although slower than the water-snakes, its movements are more rapid
than those of the vipers. The virulence of its poison is shown by the circumstance
that a lizard bitten by one of these snakes died in a minute and a half.
Nocturnal Tree- The tropical regions of the Old World are the home of the typical
Snakes. genus (Dipsas) of the subfamily, which is characterised by the
long and compressed body and tail, the sharp distinction of the head from the neck,
the moderate or large size of the eye, with its vertical pupil, and the normal
arrangement of the shields on the head, in which the hinder nasal is more or less
markedly hollowed. The number of teeth in the hinder upper jawbone varies from
ten to twelve, the two or three hinder pair being elongated and grooved ; while in
the lower jaw the front teeth are the largest. The scales on the body are arranged
in from seventeen to twenty-seven longitudinal rows, those of the middle row of
the back being larger than the rest ; and the medium-sized or long tail has its inferior
shields in two rows. These snakes are represented by about twenty species,
inhabiting Southern Asia, New Guinea, Northern Asia, and Africa. The majority
are inhabitants of forests or scrub-jungle, and are almost entirely arboreal ; but a
few are terrestrial, and frequent open country, Many of these snakes attain a
length of 6 or 7 feet, and their prevalent ground-colours are brown and black.
The Indian forms at least are purely nocturnal, and their food consists of mammals,
birds, and, more rarely, lizards, and occasionally birds' eggs. It is noteworthy that
some species prey entirely on mammals, while others confine their attention to
birds. Eight species of the genus are recorded from India, Ceylon, and Burma ;
while a well-known Malayan form is the ularburong (Dipsas dendrophila).
Back-Fanged These snakes are represented by two important genera, of which

Tree-snakes. Philodryas is mainly characteristic of the tropical parts of America,
although it also occurs in the West Indies and Madagascar ; while the whip-snakes
(Dryopkix) are confined to India and the Malay countries. In the American genus
the hinder fangs are not very large, being not double the height of the solid teeth
in front of them. The body and tail are elongated and more or less compressed,
the eyes large, and the smooth or keeled scales arranged in from seventeen to
twenty-one rows ; while the prevailing colour is green. The genus is represented
by some fifteen species, among which the green snake (P. viridissimus) is a well-
known form. This species attains a length of nearly three feet, and has upwards
of two hundred shields on the lower surface of the body.

In the Indian whip-snakes the teeth in the posterior upper jawbone vary in
number from twelve to fifteen, one or two near the middle being much enlarged
and fang-like. After these comes an interval devoid of teeth, and at the hinder-
end of the jaw the two last teeth are grooved. In the lower jaw the third or
fourth tooth is enlarged and fang-like ; those in the hinder-part of the series being



218 SNAKES.

snmll and uniform. The head is long, and markedly distinct from the neck ; and the
eye rather small, with a horizontal pupil. The scales investing the elongated and
compressed body are smooth and without pits, and arranged in fifteen oblique rows,
those down the middle of the back being slightly enlarged. The shields on the
under surface of the body are rounded, and those beneath the tail form two
rows. Deriving their name of whip-snakes from the extreme elongation and
slenderness of the body and tail these serpents move awkwardly enough on a flat
surface, although when coiling and climbing among the branches of trees their rapid
movements are graceful in the extreme. While retaining their hold by means of a
few coils of the tail thrown round a branch, the length of their body enables them
with ease to reach another at a considerable distance, or to dart forth their head in
order to seize any hapless bird or lizard that may be within striking distance.
Sharp-Nosed Nearly allied to the preceding are the sharp -nosed snakes

Snakes. (Oxybelis), of which seven species inhabit Central and South America,
while the eighth is found in Central and Western Africa. These have small
heads, with the snout narrow and elongated, and the rostral shield projecting
considerably beyond the lower jaw. The neck is thin and slender, the body
greatly elongated and laterally compressed, and the long and thin tail tapering to
a fine point. The upper jaw carries seventeen solid teeth of nearly equal size, and
four large fangs. In appearance and habits these snakes closety resemble the
whip-snakes.

Oriental Fresh- Brief reference must be made here to a group of nine genera of

Water Snakes, aquatic snakes from India, Burma, China, New Guinea, North Australia,
and the adjacent countries, which constitute a second subfamily (Homalopsince) in
the hind-fanged series. From the preceding subfamily they may be readily dis-
tinguished by the position of the nostrils on the upper surface of the muzzle ; while
they are further differentiated by their thoroughly aquatic habits. It will be
unnecessary to particularise the various genera ; but it may be mentioned that the
typical genus, Homalopsis, belongs to a group in which the two nasal shields of the
head are in contact ; and that in a second group, as represented by Cantoria, they
are separated by an internasal shield. Most of these snakes are of small size, few of
them exceeding a yard in length, while many are considerably smaller. Although
mainly fresh-water snakes, seldom coming to shore, a few members of the group
enter the sea. Many of them are furnished with prehensile tails, by means of
which they attach themselves to convenient objects; and the majority feed
exclusively on fish, though a few prefer crustaceans. Their young are produced
alive in the water.

The beautiful but venomous coral-snake (Elans corallinus) is the
Coral- Snake.

best known representative of a genus which brings us to the third

and last series of the great family under consideration. All the members of this
front-fanged series (Proteroglypha) are characterised by having the front teeth <>!'
the hinder upper jawbone, or maxilla, grooved, and the posterior ones simple and
solid. These snakes are all poisonous; and they are divided into two subfamilies,
according to their habits and the conformation of the tail. In the first, or Klapine
subfamily (JSlapince) the tail is cylindrical ; the snakes themselves being either
terrestrial or arboreal in their mode of life. These Elapine snakes are distributed



COLUBRINE GROUP.



219



in larger or smaller numbers over Asia, Africa, and America, and are especially
abundant in Australia, where they form by far the greater moiety of the ophidian
fauna, All of them doubtless on account of the immunity from attack conferred
by their poisonous character are remarkable for the beauty of their coloration.

The coral-snake and its allies constitute a genus well represented in the
warmer regions of America, but also occurring sparingly in South Africa. They
are small, although rather long and plump serpents, with the body cylindrical, the
head flattened and scarcely differentiated from the neck, and the tail short. The
small eye has a circular pupil, the mouth is narrow, and the jaws admit of but
slight dilatation. Superiorly, the body is clothed with equal-sized, smooth scales,
arranged in fifteen rows ; while inferiorly the body-shields are rounded, the anal







CORAL-SNAKE ( nat. size).



one being undivided, and the shields beneath the tail arranged in a double series.
Behind the fangs, the teeth are all small. One of the handsomest members of a
beautiful group is the coral-snake, which inhabits a large part of South America,
and also occurs in the West Indies. Attaining a length of from 2 feet to 2| feet,
this snake has its ground-colour a brilliant cinnabar-red, with a special lustre on
the under-parts. On the body this red colour is divided into sections of equal
length by broad black rings, bordered by more or less distinct greenish white
margins ; all the red and greenish portions showing black spots on the tips of the
scales. The front of the head, as far back as the hinder end of the frontal shields,
is bluish black : at the back of the parietal shields there commences a greenish
white crossband, running behind the eye, and occupying the whole of the lower
jaw; and after this comes a black neck-ring, followed by one of the red spaces of
the body. As a rule, instead of being red, the tail has alternations of black and
whitish rings, with its tip whitish. The coral-snake is generally met with in



22O



SNAKES.



forests, the neighbourhood of human dwellings it strictly avoids. Somewhat slow
in its movements, it is unable to climb trees ; and its food consists of other snakes,
lizards, insects, and centipedes.

Resplendent In Asia the place of the coral-snake and its allies is taken by a

Adders. group of nearly allied species which may be collectively termed
resplendent adders. From the last genus these are distinguished by the presence
of a distinct groove along the whole of the front surface of the upper fangs, and
also by the scales being arranged in thirteen rows. None of the teeth behind the
fangs are solid, and the shields on the head (among which the loreal is wanting)
are of large size.- A further difference from the American genus is to be found in
the presence of postfrontal bones in the skull. These adders, which are mostly




LONG-GLANDED SNAKE AND MASKED ADDER (J nat. size).

less than 3 feet in length, are represented by seven species, spread over the Oriental
region, Southern China, and Japan. The masked adder (Callophis niaccldlandi),
which attains a length of 26 inches, and ranges fronl Nipal to the south of China,
is generally reddish brown above, with regular black, light-edged transverse rings
placed at equal distances from one another ; the under-parts being yellowish with
black crossbands or squarish spots. The resplendent adders resemble the coral-
snake in the slowness of their movements, and their inability to ascend trees ; their
favourite resorts being hilly districts. They closely resemble the harmless snakes
of the genus Calamaria, upon the different species of which they chiefly feed.
Long-Gianded Closely allied to the preceding are two snakes from Burma and

snakes. the Malayan region which merely differ in that the poison-glands,
instead of being confined to the back part of the head, extend along each side of
the body for about a third of its total length, gradually thickening till they end in
front of the heart in club-shaped expansions. The heart being thrown further



COLU1UUNE GROUP.



221



back in the body than ordinary, these snakes may be recognised externally by the
thickening of that region. The figured species (Adeniophis intestinalis) is an
extremely elongated and slender snake, inhabiting Burma and the Malayan Islands,
and attaining a length of 2 feet. It is generally brown above with a yellowish
black-edged line running down the middle of the back, and a nearly similar one on
each side of the body ; the under-parts being banded with yellow and black.

Although the native name crait applies properly only to a single
member (Bungarus cceruleus) of this genus, it may be conveniently
extended to include the whole of the eight species, which range from India to the
sou tli of China, five occurring in India and Ceylon. Closely connected with the



Craits.




BANDED ADDER, OR RAJ-SAMP (J Hat. Size).

resplendent snakes by the genus Hemibungarus, in which a solid tooth is present
behind the fangs, the craits have from one to three small solid teeth behind these ;
and the smooth scales are arranged in thirteen or fifteen rows, with the middle row
of the back larger than the others. The head resembles that of the last genus in
being imperfectly distinguished from the neck, as well as in the size and number of
its shields ; while the small eye has a similar round pupil. The tail is of moderate
length, or short, with the shields on its lower surface arranged in either a double
or single series. The banded adder (B. fasciatus) belongs to a group in which
the shields on the lower surface of the body are very large, and broader than long ;
those of the tail being arranged in a single series. The species is distinguished
by the presence of a distinct ridge along the back, by the obtuse extremity of
the tail, and by the front temporal shield of the head being scarcely longer than



222 SNAKES.

deep ; these three features distinguish it from the blue adder or crait (B. cwruleus)
and the nearly allied Ceylon crait (B. ceylonicus). The banded adder, or raj-sump
(king-snake), ranges from Bengal to Java, and commonly measures about 4 feet
in length, although it grows to 6 feet. In colour it is bright yellow, with
black rings equal to or exceeding in length the light interspaces ; while on the head
a black band commences between the eyes and widens towards the nape of the
neck ; the tip of the muzzle being brown. The crait is of a dark, almost steel-blue
black, or chocolate-brown, colour, with narrow white crossbars, streaks, or rings of
white ; the under surface being of a dark livid hue, or whitish or yellowish. It
inhabits the whole of India, but is not so large as the raj -samp, which is probably
as poisonous, though it does not come much into contact with human beings, and
is, therefore, a less terrible destroyer of life. The crait frequently insinuates itself
into houses, where it conceals itself in bathrooms, verandahs, cupboards, or between
the bars of shutters; while an instance is on record where one was discovered
coiled up beneath the pillow of a palki in which a lady had made a night's journey.
Next to the cobra, the crait is credited with killing more human beings in India
than any other snake.

The name " cobra de capello," or hooded snake, was applied by
the Portuguese in Ceylon to the common Indian representative of a
genus of deadly serpents distinguished from the craits by their power of inflating
the neck, and likewise by the scales in the middle of the back not being larger
than the rest. By Europeans these snakes are now general!}' known by the name
of cobras. Agreeing with the craits in having the fangs furnished with a complete
groove on the front surface, and likewise by the presence of from one to thive
solid teeth behind them, the cobras have the head distinct from the neck, and
covered with large shields, among which the loreal is wanting ; the eye being rather
small, with a round pupil. The body is cylindrical, with the smooth scales disposed
in fifteen or more oblique rows; while the tail is of moderate length, with its
inferior shields in either a single or a double series. The dilatation of the neck,
which always takes place when they are excited and about to strike, at once serves
to distinguish the cobras from all other snakes. Cobras are confined to Africa and
Southern Asia, and are represented by six or seven species, two of which are found
in India and a third in Java and Borneo, the others being African. Of the Indian
forms, by far the most abundant is the common or true cobra (Naia tripudia n*}
which is known to the natives of India as the kala nag or kala samp (black snake).
Distinguished by having no large shields on the head behind the parietals, and by
the whole of the shields on the under surface of the tail being arranged in a double
series, this snake is a very variable species as regards coloration, some examples
having a dark spectacle-like mark on the back of the hood, while others have only
a single eye-like spot, and others, again, have no mark at all in this region. In
regard to coloration, Mr. Boulenger remarks that the hue of the upper-parts may
be greyish brown or black, with or without a spectacle or loop-shaped black
light-edged marking on the neck or with light spots or crossbands on the body ;
while beneath it varies from whitish, through brownish, to blackish, sometimes
with black crossbars on the fore-part of the body. Occasionally attaining a length
of a few inches over 6 feet, while an instance is on record where a specimen



COL UJ1RINE GR O UP.



223



measured upwards of 7 feet 3 inches, this cobra is distributor! over tho \vholo of
India and Ceylon, ranging westwards through Afghanistan to the Caspian, and to
the east to the Malayan region, and the south of China. The other Indian species,
or giant cobra (N. bunyarus), is a larger snake, distinguished by the presence of a
pair of large shields on the head behind the parietals, while the shields beneath the
tail usually form only a single series. When adult, its colour is yellowish or brown,




YOUNG GIANT COBRA OR HAMADRYAD (} liat. Size).

with more or less distinctly marked dark crossbands ; but young specimens are
usually black, with yellow rings on the body and bars on the head, and in some
instances there are light spots on the upper surface, and the inferior shields are
whitish with black margins. In size, the giant cobra is known to measure as much
as 13 feet, and probably grows larger. Fiercer than the common species, this
cobra is fortunately far less abundant ; its range extending from India through
Burma and Siam to the Malayan region and the Philippines. Another species is
the asp or Egyptian cobra (N. haie), which is widely spread over Africa, and



224 SNAKES.

presents great variations in colour. Somewhat exceeding in size the true cobra,
the asp is distinguished by the sixth upper labial shield of the head much
exceeding the others in length, and uniting with the temporal, so as to form a large
plate, which anteriorly comes in contact with the postocular shield. In most
Egyptian examples the colour of the upper-parts is uniformly straw-yellow, while
the under-parts are light yellow ; but there may be dark crossbands on the under
surface of the region of the neck, which sometimes unite into a patch. The straw-
colour may, however, shade into blackish brown and occasionally the hues may be
brighter.

Our account of the habits of these snakes will be mainly confined
to the common Indian species, and since these have been specially
studied by Sir J. Fayrer we shall paraphrase or quote from his writings. Although
frequently seen in motion during the day, cobras are most active during the night ;
and they feed chiefly on small mammals, birds' eggs, frogs, fish, and even insects.
The giant cobra subsists, however, almost entirely on other snakes ; and the other
species will occasionally rob hens' nests, swallowing the eggs whole. In captivity,
cobras will live weeks and even months without tasting food of any kind or
touching water. Although essentially terrestrial, they will readily enter water, in
which they swim well ; while they occasionally climb trees in search of food, and
are often found, more especially during the rainy season, in old buildings and walls,
or in wood-stacks and heaps of rubbish. It is when collected in such situations
that they are most commonly trodden upon by the natives and more frequently
at night than at other times with the well-known fatal results. These snakes
lay from eighteen to twenty-five oval eggs about the size of those of a pigeon.
Ascending to a height of some eight thousand feet in the Himalaya, the common
cobra " is equally dreaded and fatal wherever met with ; fortunately it is not
naturally aggressive, unless provoked, at which times its aspect is most alarming.
Raising the anterior third or more of its body, and expanding its hood, with a loud
hissing, it draws back its head prepared to strike, and, when it does so, darts its
head forwards, and either scratches, or seizes and imbeds its fangs in the object of
attack. If the grasp be complete and the fangs imbedded in the flesh, dangerous
and often fatal effects result ; but if the fangs only inflict a scratch, or if the snake
be weak or exhausted, the same great danger is not incurred. If the poison enter
a large vein and be quickly carried into the circulation, death is very rapid; men
having been known to perish from cobra-bite within half an hour. The largest
and strongest as well as the smallest and weakest creatures succumb ; but, fortun-
ately, all who are bitten do not die. In the first place, some human beings, as \vell
as lower animals, have greater tolerance than others of this or of other poisons a
result, doubtless, of idiosyncrasy or varying degrees of nervous energy which
enables one to resist that to which another would yield; or a wound may have



Online LibraryRichard LydekkerThe new natural history (Volume 5) → online text (page 24 of 62)