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been inflicted and yet but little of the poison inoculated ; or, in the third place, the
snake may be weak or sickly, or it may have been exhausted by recent biting, and
thus have become temporarily deprived of the power of inflicting a deadly wound.
But when a cobra in the full possession of its powers bites, and injects the poison
into man or beast, it is almost surely fatal, and all the remedies vaunted as infallible
antidotes are futile."



COLUBRINE GROUP.



225



Death-Adders.



Among the deadliest of Australian snakes is the purplish
death-adder (Pseudeckis porphyriaca), alone representing a genus
characterised by the great elongation and slenderness of the cylindrical body, the
sharply pointed tail, the small head, imperfectly differentiated from the neck and
clothed with large shields, the smooth scales, arranged in from seventeen to twenty-
three rows, the divided anal shield, and the arrangement of the shields on the




SHORT DEATH-ADDER, AND SPINE-TAILED DEATH-ADDER (J nat. size).

under surface of the tail at first in a single, and posteriorly in a double series.
Behind the fangs are one or two solid teeth in the upper jaw ; the pupil of the eye
is round ; and the neck cannot be dilated. This snake, which grows to a length of
about seven feet, is very variable in coloration. Generally, however, the colour of
the back varies from a shining purplish black to dark olive-brown, the under-
parts being red, and the sides carmine ; but the latter colours not occupying the
centres of the scales, which are black, as are the hinder borders of the shields of
the under surface. Generally known to the settlers by the name of the black
VOL. v. 15



226 SNAKES.

snake, this reptile is dreaded alike by natives and Europeans, although, fortunately,
it nearly always endeavours to escape when discovered. The short death-adder
(Hoplicephalus curtus), represented in the upper figure of the illustration
on p. 225, is selected as a well-known example of a second Australian genus,
which includes a large number of species. Closely resembling the harmless snakes
in general appearance, these death-adders are distinguished from the other members
of this group by the presence in the upper jaw of a row of small, curved, solid
teeth behind the fangs. The head is unsymmetrically four-sided, flattened, and
rounded at the muzzle, the body massive, and the tail either moderate or short.
The smooth and equal-sized scales are arranged in from fifteen to twenty-one rows.
those on the middle of the back not being larger than the rest ; and there is but
a single row of shields on the under surface of the tail. All these species are
peculiar in the group for producing living young, The figured species, which
varies from 3 to 4 feet in length, has a short tail, and nineteen rows of scales.
Although very variable as regards coloration, the head is generally uniform black,
the body olive-colour, with broad brown or black crossbands, the hinder-part of
the body and the upper surface of the tail uniformly blackish, and the whole
of the under-parts light yellow. Some specimens have, however, no dark bands
on the back. The spine-tailed death-adder (Acanthopis antarcticus), depicted in
the lower figure of the illustration, represents a genus easily recognised by the
horny appendage with which the tail terminates ; the middle row of scales in
the fore-part of the body being more or less distinctly keeled. In addition to
Australia and New Guinea, this snake also inhabits the Eastern Moluccas, as well
as Ceram and Amboyna. It feeds chiefly upon frogs and young birds and is
regarded by Europeans as most deadly, although the natives believe that no one
ever dies from a death-adder's bite.

The sea-snakes are now considered to represent merely a sub-

S63.-SU3.lC6S

family (Hydrophiince) of the front-fanged Colubrines. From tlie
preceding subfamily they are distinguished, not only by their marine habits,
but likewise by their strongly compressed and oar-shaped tails, in the skeleton of
which both the superior and inferior spines of the vertebrae are very strongly
developed. With the exception of the broad-tailed sea-snakes, which form a kind
of transition between the present and preceding subfamilies, these snakes never
leave the water; and the inferior surface of the body and tail is either covered
with scales similar to those on the upper-parts, or, if shields are present, they are
of small size. All are very poisonous, and produce living young. Their head-
quarters are the coasts of the Indian Ocean and the tropical districts of the
Western Pacific, their range extending from the Persian Gulf to New Guinea
and Northern Australia. The parti-coloured sea-snake has, however, a more
extensive distribution, ranging from the western coast of Africa to the western
shores of Tropical America, and extending as far north as Japan and Mantchuria,
and as far south as New Zealand. All of them have relatively small heads, jaws,
and fangs ; and while in some cases the body is short and thick, in others it is very
thick only in the region of the tail, and elsewhere disproportionately elongated
and attenuated. Always varied, the coloration is often brilliant and beautiful;
and the oar-like form of the tail and hinder-part of the body is obviously an



SEA-SNAKES.



227



adaptation to an aquatic life. Living in the sea, or in tidal waters, their move-
ments in the clear blue water are agile and elegant ; but when thrown ashore,
as frequently happens, the majority are helpless. Their food consists of fish and
such other creatures as they can capture in the sea. In parts of the Bay of Bengal,
sea-snakes are sometimes seen congregating in large shoals. The group is divided
into nine genera, no less than six of which are represented in Indian waters.
Broad-Tailed The broad-tailed sea-snakes, of which there are three species,

sea-snakes, constituting the genus Platurus, in general appearance closely
resemble some of the craits, especially as regards the shape of the skull and the
scaling of the head and body, but are distinguished by the compression and depth




BANDED SEA-SNAKE (J liat. size).

of the tail In the upper jaw, which is very short, there is in the maxilla of each
side a pair of large grooved fangs, followed by a single very small solid tooth.
The arrangement of the shields of the head is normal, each nostril being pierced in
a laterally-placed nasal ; the scales on the body are smooth and overlapping, and
the inferior surface is covered with large shields. Of the three species, the banded
sea-snake (P. laticaudatus) is distinguished by the absence of a keel on the lower
surface of the hinder-part of the body, and also of an unpaired shield on the
muzzle ; the scales being arranged in nineteen rows. In colour, it is olive above
and yellowish beneath, with black rings fully equal in width to the light inter-
spaces. Attaining a length of a little over a yard, this species ranges from the
Bay of Bengal and the China Sea to Polynesia. An allied but larger species.



228



SNAKES.



(P. colubrinus), with the same distribution, is distinguished by the presence of an
unpaired shield on the head, arid the arrangement of the scales in from twenty-one
to twenty-five rows ; while the third species (P. schistorkynchus), from the China
Sea and Western Pacific, differs in having a keel along the hinder half of the
lower surface of the body. That the broad-tailed sea-snakes are the direct
descendants of terrestrial forms allied to the craits, is proved by their retention of
large inferior shields, and by their habits. Not only are these snakes frequently
found at some distance from water, but in Sumatra a specimen was captured
nearly a day's march inland.

Parti-Coloured In common with all the other members of the subfamily, the

Sea-Snake, parti-coloured sea-snake (Hydrus platyurus) has the nostrils placed

on the upper surface of the muzzle ; and the under surface of the body and tail




BLACK-BANDED SEA-SNAKE (f nat. sizi')-

in this species are scaled like the rest, although in some of the genera traces of
enlarged shields still persist. In the skull, the maxilla is considerably longer than
the transverse bone, and carries a pair of short fangs, followed, after an interval,
by seven or eight solid teeth ; the muzzle is elongated ; the head-shields are large,
the nasals being in contact with one another; and the scales on the relatively
short body hexagonal in form and with their edges in apposition. This snake
attains a length of a yard; and in colour is either yellowish with symmetrical
black transverse bands or spots, or uniformly black above, and yellow, with or
without black spots below ; the yellow tail being ornamented with either black
spots or bars. It is the sole representative of its genus, and has a wider dis-
tribution than any other member of the group, ranging over the whole of the
Indian Ocean and the tropical and subtropical portions of the Pacific. The
tpyical sea-snakes, forming the large genus Hydrophis, differ in having from seven



VIPERINE GROUP. 229

to eighteen solid teeth in the maxilla, by the longer body, on the anterior part of
which the scales are imbricating, and by the presence of more or less distinct small
shields on the lower surface.

Black-Banded The black-banded sea-snake (Distira cyanocincta) may be taken

Sea snake. as an example of another large genus differing from the preceding in
that the fangs are followed in the maxilla by from four to ten solid teeth with
their front surface grooved. In these snakes the body is more or less elongated,
and generally has the scales on its front portion slightly overlapping, while the
under surface carries small shields. The figured species, which grows to a length
of 6 feet, is of a greenish olive above, with black transverse bars or rings, which
are sometimes connected by a longitudinal stripe on the under surface. This
snake ranges from the Persian Gulf to the Malay Archipelago and Japan, and is
one of the most abundant in the Indian seas.

There are several points in which the sea-snakes differ from their land cousins
I as regards habits, in addition to those already noticed. In the first place, the skin
i is changed piecemeal, instead of entire ; the casting taking place at very frequent
intervals. Moreover, the tongue is very short, and only the extreme tips of its
two extremities are exserted through small notches on either side of the rostral
shield of the head, which is prolonged downwards so as to close the mouth,
en, however, these snakes are cast ashore and almost blinded by the unaccus-
ed light, the tongue is used in the ordinary manner as a feeler.

THE VIPERS.
Family VlPERID^;.

Omitting mention of the small and unimportant family of harmless snakes
town as blunt-heads (AmblycephalidcB), represented by two Oriental and two
tropical American genera, we pass to the viper family, which includes the
lole of the remaining members of the suborder. The distinction between a
lubrine and viperine snake is that in the latter the maxilla3 or hinder upper jaw-
bones are capable of being erected in a vertical plane at right angles to the
transverse bones, while in form they are short and thick, and they always carry
a single pair of large tubular fangs. All vipers are poisonous, and, so far as
known, produce living young ; while they are more or less nocturnal and terrestrial
in their habits, although a few ascend trees. The thick body, the flat and often
triangular head, the short and stumpy tail, the reduction of the maxillary teeth to
a single pair of fangs, and the vertical pupil of the eye, are all features dis-
tinguishing vipers as a whole from the poisonous colubrines ; but, as already
mentioned, it is frequently necessary to examine the structure of the skull itself
before any particular snake can be assigned to its proper serial position. That
the vipers form a highly specialised group is self-evident; and Mr. Boulenger
believes them to be descended from the hind-fanged colubrines. The family is
divided into two groups, namely, the typical vipers of the Old World, which
attain their maximum development in Africa, and the American and Asiatic
pit-vipers.



230 SNAKES.

Our first representatives of the Old World vipers (Viperince)
are the true vipers, which form a genus with some twenty species,
ranging over Africa (exclusive of Madagascar). Europe, and a large portion of Asia,
one of them reaching India. In common with the other members of the subfamily,
they have 110 pit in the loreal shield of the head; while they are specially dis-
tinguished by the upper surface of the head being covered either with scales or
small shields, and by the keeled scales of the body running in straight longitudinal
rows, which vary in number from twenty-one to thirty-eight ; and likewise by the
double row of shields beneath the tail.

The common viper (Vipera verus), which is happily the 'only
Common Viper.

British poisonous snake, is one of the smallest representatives of the

genus, and is distinguished by the mixture of scales and shields on the head (three
of the latter being larger than the rest), and the general presence of only a single
row of scales between the eye and the upper labial shields beneath. In colour and
markings the common viper is extremely variable ; but as a rule a dark zig/ag
stripe runs down the whole length of the middle of the back. With regard to
coloration, in some specimens the ground-colour is nearly olive, in others a deep
rich brown, and in others a dirty brownish yellow ; while a mark between the
eyes, a spot on each side of the hinder part of the head, the above-mentioned zig/ag
line formed of confluent quadrangular spots on the back, and a row of small
irregular triangular spots on each side of the body, are of a darker hue than the
ground-colour, and are frequently nearly black. In some examples the under-
parts are lead-colour, with lighter or darker spots, while in others they are almost
wholly black. Bell records a specimen in which the ground-colour was nearly
white and the markings black ; and in one variety the ground-colour is brick-red,
with ferruginous markings ; while in a second the under-parts acquire a more or
less marked blue tinge ; and in a third the whole skin, with the exception of that
beneath the jaw and throat is black, the usual markings being visible in certain
lights. The average length of the common viper is about 10 inches. Its geo-
graphical distribution is greater than that of any other European snake, extending
from Portugal eastwards to the Island of Saghalien, while northwards it reache
to the Arctic Circle, and southwards to Central Spain.

In South-Western Europe the common viper is replaced
Southern Viper. . it-

accompanied by a closely-allied torm which may be called tl

southern viper (V. aspis), regarded by some writers as a distinct species, and
others as a mere variety. As it was doubtless to this snake that the Latin tei
Vivipara was applied. German writers restrict the name viper to the southei
form, and use the term Kreuzotter for the common viper. In the latt
the front of the upper surface of the head is covered with three distinct small
shields, but in the southern form it is clothed only with smooth or slightly rid<
scales, among which seldom more than a single polygonal roundish one can
regarded as representing a frontal shield ; moreover, instead of the single row
small scales generally separating the eye of the common viper from the
labial shields, the southern form always has two such rows. There is likewise
difference in the shape of the muzzle in the two forms. The southern viprr in;
be considered characteristic of the Mediterranean countries, occurring in Nortl




A FAMILY OF VIPEHS.



VI FERINE GROUP.



233



Africa as well as in Europe. It is noteworthy that in the borderland of the
distributional areas of the two forms, such as Northern Spain and Italy, it is
difficult to say to which of the two any specimen may belong.

More numerous in Scotland than the ringed snake, but, like it, unknown in
Ireland, the common viper generally frequents heaths, dry woods, and sandy banks.
Although its bite produces severe effects, it is seldom, unless the sufferer be very
young or in ill-health, that death ensues. During the winter months, vipers
generally hibernate in small parties for the sake of mutual warmth, several being
often found twined together in a torpid condition.




LONG-NOSED, OR SAND-VIPER (\ nat. size).

Long-Nosed Another well-known poisonous European snake is the long-

Viper, nosed, or sand-viper (V. ammodytes), easily recognised by the
presence of a soft horny appendage at the end of the nose, covered with scales,
and not unlike a conical wart in appearance. It is also distinguished from the
common viper by the absence of any large shield, except the supraoculars, on the
top of the head ; although in coloration the two species are very similar. In size
it is the largest European representative of the group, attaining a length in some
rare instances of just over a yard. The sand-viper ranges from Italy to Armenia.
In Carinthia it is the commonest of snakes, while in the Tyrol it is local, but
abundant in the south of Hungary and Dalmatia. Mainly nocturnal, it is much
more commonly found in hilly than in level districts, ascending in the mountains



234



SNAKES,



to a height of between three thousand and four thousand 'feet. Except during
the pairing-season, when it is found in couples, it is a solitary creature, subsisting
on other snakes, mice, voles, birds, and lizards.

As lieinef one of the deadliest of Indian snakes, we may take
Russell s Viper.

as our next example or the genus the beautitul Russell s viper

( V. russelli), of India, Ceylon, Burma, and Siam. From the other viper inhabiting
Kashmir, this species ma}' be distinguished by having the rostral shield of the
head as long as broad, and the scales on the body arranged in from twenty-seven
to thirty-one rows. Sometimes known as the chain-viper, this snake attains a




RUSSELL'S VIPER (1- nut. size).

length of 4 feet. Its ground-colour is pale brown, with three longitudinal series
of black light-edged rings, sometimes replaced by faint dark spots; the lower-
parts being yellowish white, either with or without small crescentic black spots.
In young specimens, as shown in our illustration, the black rings on the upper-
parts surround dark reddish brown spots, which in the middle series are in contact
with one another. Sir J. Fayrer regards this snake as being, next to the cobra,
the most dangerous in India, stating that fowls bitten by it sometimes expire
in less than a minute. "It is nocturnal in its habits, is sluggish, and does not
readily strike unless irritated, when it bites with great fury ; it hisses fiercely and
strikes with vigour. Its long movable fangs are very prominent objects, and with
them it is capable of inflicting deep as well as poisoned wounds. When disturbed,



VI FERINE GROUP.



235



its loud hissing is calculated to warn those who approach it, and it does not
appear to cause many human deaths, although it may be that its misdeeds are
sometimes ascribed to the cobra. This viper is said to frequently kill cattle while
grazing, by biting thereabout the nose or mouth. In proof of its sluggish nature,
there is a well-authenticated tale of a young person having picked one up, and,
mistaking it for an innocent snake, carried it home ; its true character being only
discovered when it bit a dog."

In Africa the place of Russell's viper is taken by the dreaded
puff-adder ( V. arietans), whicli occasionally attains a length of 6 feet.
It is the only member of the genus in which the unusually small nostrils open



Puff-Adder.




THE PUFF-ADDER (* liat. size).

upwards near the extremity of the muzzle; and it is further distinguished by
having a supranasal shield, covered, like the region of the brow, with upright
horny scales or spines. In appearance most hideous and repulsive, this snake has
the large and flattened head triangular in shape, very broad and blunt at the
muzzle, and sharply defined from the body, the latter being thick and almost
triangular in section. Both head and body are covered with keeled overlapping
scales, differing from one another only in size, and arranged on the body in from
thirty-one to thirty-three longitudinal rows, and forming three or four series
between the eyes and the upper labials. The coloration and marking vary to a
certain extent individually ; but there is a great change in the brightness of the
tints immediately after the changing of the skin. The puff-adder is spread over



236



SNAKES.



nearly the whole of Africa, and is everywhere dreaded from its deadly nature.
Inhabiting dry and sandy places, it derives its name from its habit, when angry or
alarmed, of drawing in a full breath and causing the body to swell visibly, Then
the air is allowed to escape gradually, producing as it does so a prolonged sighing
or blowing sound which continues till the lungs are emptied, this process being
repeated so long as the provocation lasts. Usually this reptile lies half-hidden in
the sand, with its head fully exposed, and when approached merely rises without
attempting to escape, and so virulent is its bite that even horses have been known
to die within a few hours after being struck. The poison is used by the bushmen
for their arrows, to the tips of which it is made to adhere by being mingled with
the viscid juice of the amaryllis.




HORNED VIPERS IN THE SAND ( liat. size).

Horned Vi er Next to the southern viper, or asp, no serpent was more feared

by the ancients than the Egyptian cerastes, or horned viper (Cerastes
cornutus). As a genus, the two species are characterised by the small crescentic
nostrils situated on the sides of the muzzle, the presence in the male, and some-
times in the female, of a pair of scale-covered, horn-like processes above the eyes,
the arrangement of the scales of the body in oblique rows, and the short keels on
the scales, which stop short of their tips. The common horned viper may be
immediately recognised as an inhabitant of desert places from the general sombre
and mottled tone of its coloration, which is so admirably adapted to such surround-
ings. Usually attaining a length of about 2 feet, it is of a light brownish ground-



VIPERINE GROUP.



237



colour, more or less tinged with yellow, upon which are six longitudinal rows
of circular or quadrangular dark markings, increasing in size from the middle
of the back towards the sides. Beneath the eyes runs a dark brown band, while
the middle of the head is marked by a light brownish yellow streak, dividing
posteriorly, and uniting on the sides of the neck with another stripe coming from
the chin. The scales surrounding the mouth are a bright sandy yellow, the
shields on the under surface being also either bright yellow or whitish. The
scales of the body are arranged in from twenty-nine to thirty-three rows ; the anal
shield is single, while the shields beneath the tail form a double series. The range
of this snake includes Northern Africa, East of Morocco, as well as Kordofan and
Arabia ; the second species being likewise North African. Canon Tristram writes
that the usual habit of the horned viper is " to coil itself on the sand, where it
basks in the impress of a camel's footmark, and thence suddenly to dart out on




THE EJA, OR DESERT SAW-VIPER (f liat. size).

any passing animal. So great is the terror which its sight inspires in horses,
that I have known mine, when I was riding in the Sahara, suddenly start and rear,
trembling and perspiring in every limb, and no persuasion would induce him to
proceed. I was quite unable to account for his terror, until I noticed a cerastes
coiled up in a depression two or three paces in front, with its basilisk eyes steadily
fixed on us, and no doubt preparing for a spring as the horse passed." According
to Bruce, this snake, when about to attack, moves rapidly forward with a
sideways motion, unlike that of any other serpent. Attacking when quite
unprovoked, the horned viper is more dreaded than any other North African
snake, men frequently dying from its bite within half an hour. Its food consists
of desert-haunting rodents, together with lizards, and perhaps birds.

Desert Saw- While agreeing with the horned vipers in having the lateral

vipers. body-scales arranged in oblique rows, the present genus may be dis-
tinguished by its two species having but a single series of shields beneath the tail,



Online LibraryRichard LydekkerThe new natural history (Volume 5) → online text (page 25 of 62)