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the absence of a f ronto-squamosal arch to the skull ; while it is further character-
ised by the serration of the crest, and the orange and black-spotted coloration of
the under-parts. The total length varies from 5 to 5f inches, and the toes of both
limbs are free. The colour of the upper-parts is brown, blackish, or olive, with
more or less distinct black spots ; the sides are white-spotted ; and the under-parts




MALE AND FEMALE OF MARBLED NEWT (liat. size).

orange, with black spots or marblings. During the breeding-season the head of
the male is marbled with black and white, and there is a silvery band along the
sides of the tail ; while in the female the under surface of the tail is uniformly
orange. The toes are yellow with black rings. An inhabitant of Britain, this
species is spread over the greater part of Europe, extending as far north as
Sweden, but unknown in Italy, and ranging eastwards to Greece, Turkey, and
Russia. Not improbably Blasius's newt (M. blasii\ from North- Western France,
is a hybrid between the present and the next species, having the form and
coloration of the former, but the fronto-squamosal arch of the latter.



296 NEWTS AND SALAMANDERS.

Of the other European species, one of the handsomest is the
Marbled Newt.

marbled newt (M. marmorata}, from France, Spain, and Portugal, of

which a male and female are represented in the illustration on p. 295, Having
a ligamentous fronto-squarnosal arch to the skull, this species is specially dis-
tinguished by the smooth dorsal crest of the male, and by the under-parts being
generally dark with white dots. The total length is about live and a quarter inches.
In general colour the upper-parts are green with black marblings ; the crest of the
male being ornamented with black and white vertical bars, while in the female an
orange streak runs down the middle of the back. The sides of the tail have a
silvery white band, most distinctly marked in the male during the breeding-season ;
the under-parts are brown or greyish, with more or less distinct darker spots, and
dotted with white ; and the green toes are marked with black rings. Rare in
France, this species is common in Spain and Portugal ; and it lives in ponds
and streams only in the early spring, spending the remainder of the year on
dry land.

The next species for notice is the Alpine newt (M. alpestris),
represented in the illustration on p. 289, which differs from the last by
the much lower dorsal crest of the males, and likewise by the uniformly orange
colour of the under-parts. In size it is a comparatively small species, varying from
three and a quarter to four inches in length. In colour the upper-parts, which may
be either uniform or with darker marblings, vary from brown, greyish, to purplish ;
the sides have a series of small black spots on a whitish ground, beneath which, in
the male during the breeding-season runs a sky-blue band ; the crest on the back
and tail is white with round black spots ; the throat is frequently dotted with
black ; the under-parts are uniform orange or red ; and the lower edge of the tail
of the female is orange spotted with black. The Alpine newt inhabits Franco,
Belgium, Holland, Germany, Switzerland, Austria, and the north of Italy.

A fourth European representative of the genus is the small common
Common Newt. . i

newt (M. vulgaris), which belongs to the same group as the preceding,

and is distinguished by the festooning of the dorsal crest, the lobate hind-toes of
the male, and the black-spotted under-parts. Abundant in almost every English
pond and ditch, where the water is sufficiently clear, this species ranges all over
Europe, with the exception of the south of France, Spain, and Portugal, and is
likewise widely distributed in temperate Asia. It measures about three and a
quarter inches in length, and has a nearly smooth skin. The upper-parts are brown
or olive in colour, with darker spots, larger and more rounded in the male than in
the female ; the head is marked with five longitudinal dark streaks ; the under-
parts are yellowish, with a median orange or reddish zone, and marked with black
spots in the male, and dots of the same in the female. In the latter the lower e<luv
of the tail is uniformly orange, whereas in the male it is red, bordered with blue
and interrupted by vertical black bars.

The last of the European species we can notice at length is the

webbed newt (M. palmntoi), distinguished from all the preceding by

the bony fronto-squamosal arch to the skull, and likewise by the webbed hind-toes

of the male. This is the smallest species yet noticed, its length not exceeding three

inches. The colour of the upper-parts is brown or olive, with small dark spots on






NE IVTS.



297



the body and longitudinal streaks on the head. In the male there are also minute
brown speckles on the head ; and the dorsal, as well as the upper part of the caudal
crest, together with the hind-feet, are blackish. Except for a median orange zone,
the under surface is uncoloured, although there may be a few small blackish dots ;
there are a series of spots along the upper and lower borders of the tail, and the
crest on its lower surface is orange in the female and bluish grey in the male,
The webbed newt has been recorded from Britain, France, Belgium, Holland,
Switzerland, Western Germany, and the north of Spain.

With the exception of the banded newt (M. vittata) of Asia
Minor and Syria, distinguished by the presence of a black band along
each side of the body, all the other members of the genus are devoid of a crest
along the back in the male. One of the most remarkable of these is Waltli's newt



Other Species.



- l'F"~A t ^J ~~~^~~ f- 1 ^^.-yzr~ : =-^-_-




MALE AND FE



Habits.



(M. waltlii), from Spain, Portugal, and Tangiers, distinguished by the elongation
of the ribs, which in some instances actually perforate the skin, so as to' form a
row of sharp points on each side of the body. In a fossil state the genus has been
recorded from the lower Miocene paper-coal deposits near Bonn.

Since the general habits of all newts are very similar, one account
will serve for the entire group ; but it must be remembered that
whereas the whole of them are aquatic during the breeding-season, at the close of
that period some species leave the water and live for the rest of the summer on
land ; while nearly all seem to pass some portion of the year out of the water.
Newts generally prefer clear and running water, with plenty of aquatic plants on
which to deposit their eggs. On land they are somewhat awkward and slow, but
in water they swim with great rapidity by the aid of their oar-like tails, their
hind-legs being pressed close to the sides of the body; their mode of progression



298 NEWTS AND SALAMANDERS.

being thus exactly the opposite to that of a frog. They often stand upright in the
water when coming to the surface to breathe, after which they will sink to the
bottom with a snake-like movement in search of prey. When on land, they sci-k
shelter beneath stones and roots, or in holes in the ground, and in such situations
often undergo their winter sleep, although such as live in deep water pass the cold
season of the year in a kind of torpor at the bottom. All newts are carnivorous or
insectivorous, and the crested newt feeds largely on the tadpoles of the common
frog, while the larger species will prey on the smaller members of their own genus.
Although there is considerable difference in the spawning-time of the various species,
the eggs are generally deposited during May or June, the female laying each egg
singly on the edge of the leaf of some water-plant, which is folded together by her
hind-feet, and thus held by the viscosity of the egg. In the course of a few days
after its deposition, the white embryo assumes an elongated form within the egg ;
and soon it is seen to be folded upon itself, with the gills well developed, and in
advance of them a pair of lobes by which the liberated tadpole affixes itself to
aquatic plants. When about a quarter of an inch in length, and while the gills are
still simple, the tadpole bursts its envelope; the front-limbs being represented
merely by a pair of small knobs behind the gills. When hatched, it swims about
in an aimless kind of way till it strikes against some object to which it can easily
attach itself, and after a short time starts on another voyage. Development now
proceeds apace, and in the course of two or three weeks the tadpole will have
attained a length of about half an inch, while the gills will have become elegantly
branched, and the fore-limbs well developed. At this period the eves assu : their
permanent character, and the mouth has become terminal, *ale the lobes for
attachment to plants are well-nigh absorbed. Still later the front feet, which had
previously been only digitated, acquire four distinct toes, and the hind-limbs make
their appearance and gradually assume their full proportions; but the gills have
become still more complex. From this date the latter appendages gradually
diminish in size, and shrivel, while the lungs are at the same time developed, until
finally, about the latter part of the autumn, the creature has completed U' 1 Mieta-
morphosis, and passed from the condition of a fish to that of a reptile. ' Althougl
in most cases newts shed their skin piecemeal, in the crested newt it has bet
observed to be cast entire.

Spectacled The presence of only four toes to each foot, and of a bony front

Salamander, squamosal arch to the skull, are the most distinctive features of tl
little spectacled salamander (Salamandrina persjncillata) of Italy, the sole repi
sentative of the genus to which it belongs. It is. however, further distinguish)
by its slender form, and also by its somewhat compressed and rapidly tapering tai
furnished both above and below with a longitudinal keel, as well as by the palatii
teeth being arranged in two parallel series diverging posteriorly. The tongue
very similar to that of the genus Ckioylossa. Reaching from rather more tlian
to nearly 4 inches in length, this pretty little salamander has a warty skin, and
generally black on the upper-parts, although there is a triangular or chevron-
shaped yellow mark on the top of the head. Beneath, the chin is white, the throat
black, and the rest of the under-parts white, usually marked with black spots ; the
lower surface of the tail and adjacent part of the body is, however, bright carmine.



AXOLOTLS.



299



The tarantolina, as this salamander is termed in Italy and Sardinia, inhabits cool,
shady spots on the flanks of the mountains, where it feeds chiefly upon ants and
spiders, and is active at all seasons of the year, having been seen abroad even in
January. Although it appears that the pairing takes place on land, the females
resort to the water in March to deposit their eggs, those that are the first to arrive
taking the best places, such as sheltered corners of rock, where the spawn will be
less likely to be washed away by floods. The young are hatched in about three
weeks, and generally leave the water in June. In its movements on land this
salamander is as active as a lizard.

There are two other existing genera of the subfamily under
consideration, both differing from the preceding forms in that the

ilia or upper jawbone is more or less fully in contact with the pterygoid bone.
Both have a fronto-squamosal arch, but whereas in Tylotriton this is bony

ughout, it is ligamentous posteriorly in Pachytriton, which has also the tail




T Genera.




SPECTACLED SALAMANDER (liat. size).

lindrical at tLj ba.se, instead of compressed throughout. The former genus, in
which the skin is extremely warty, is represented by one species from Siam and
the Eastern Himalaya, and a second from the Liu Kiu Islands, while the latter is

twn only by a single Chinese form.
Although properly speaking the term axolotl applies only to the
permanent larval form of the Mexican representative of the genus
blystoma, it will be found convenient in practice to make it include all the
members of that group, whether mature or immature. Together with certain
other genera, Amblystoma constitutes a second subfamily (Amblystomatince)
distinguished from the Salamandrince by the teeth on the palate forming a
transverse or posteriorly converging series, and being inserted on the hinder
portion of those bones known as the vomers; as well as by the bodies of the
vertebrae being cupped at each end. The type genus is specially characterised by
the palatal teeth forming a nearly straight or angulated series, not separated by a
space in the middle line ; and likewise by the radiating folds of skin on the tongue,
which are oval or nearly circular in form, with the sides completely and the front



300



NEWTS AND SALAMANDERS.



partially free. There are five hind-toes, and the tail is more or less compressed.
Represented by a number of North American species, one of which ranges as far
south as Mexico, the genus has also one Asiatic member, inhabiting the mountains
of Siam, probably at a great elevation.

The majority of axolotls pass from the tadpole to the salamander stage in
the ordinary way, but this is not the case with the Mexican race of the Mexican
axolotl (A. tigrinum), which likewise extends over a large area in the United
States. The adult form is shown in our second illustration ; and in this condition
the head is large and depressed, and has a broad and blunt muzzle, the limbs
being stout, with short toes, and the rather long tail distinctly compressed, and




LARVAL STAGE OF MEXICAN AXOLOTL (3 nat. size).

keeled above and below near the extremity. The shining skin is finely granulated,
and the general colour brown or blackish, with more or less numerous yellow
spots, which may be arranged in transverse bands. In the United States, we
believe, the transformation from the larva to the adult goes on in the ordinary
manner; but the case is very different in Mexico. The city bearing that name
is, as our readers are doubtless aware, surrounded by an extensive lake ; while
the country itself is characterised by its extreme dryness. In this lake dwell the
creatures represented in our first illustration, which are known to the natives
by the name of axolotl. It will be seen from this figure that they resemble
the tadpole stage of ordinary salamanders and newts in having large branching
gills, and a deep rudder-like tail; and the natural conclusion would be that






AXOLOTLS.



301



they are larval forms. However, in the Mexican lakes, the axolotls remain
permanently in the water, retaining their gills throughout life, and laying eggs,
as if they were adult ; and it was consequently long considered that they belonged
to a type with persistent gills. It was not, indeed, until the year 1865, that light
was thrown on the history of these remarkable creatures by six examples which
had been living for more than a year at Paris. These comprised five males and
one female, and in the middle of February the latter began to lay eggs, which in
the course of a month hatched into tadpoles like their parents. In the following
September the gills and crest of the tail of one of these began to shrivel, while the
head increased in size, and yellow spots made their appearance upon the dark skin.
Towards the end of the same month, and in the early part of October, similar
changes took place in the others, and soon afterwards the whole four assumed the



ADULT OF MEXICAN AXOLOTL (if II at. size),




iarance of the salamander, which had been previously described as Amblystoma
Subsequently experiments were made with other young axolotls by
placing them in a glass vessel filled with water, but with rocks at one end, so that
the creatures could creep out and expose themselves to the air as much as they
pleased. After a day's interval the amount of water in the vessel was diminished ;
and almost immediately the gills of the axolotls began to shrink, and in the course
of time, during which they dwelt chiefly in damp moss, the creatures gradually
developed into air-breathing salamanders. It has been inferred from these
remarkable experiments that the Mexican axolotl, like the other members of the
genus to which it belongs, originally went through the normal series of trans-
formations ; but that, owing to the dry nature of the country it inhabits, it has
acquired the habit of retaining the larval condition permanently. From its being
able to breed in this state, it may further be inferred that the tadpole stage was



302 NEWTS AND SALAMANDERS.

originally the permanent condition of all members of the order, and that the
salamander stage is a later development.

There are six other genera, belonging to the subfamily Ainbly-
stomatince, of which Hypnobius is represented by several Japanese
species. Salamandrella, distinguished by having only four hind - toes, is a
Siberian type, with two species ; Onychodactylus, which may be recognised by its
black claws, is known by one species from Japan ; while Ranidens, from Eastern
Siberia and North-Eastern China, Batrachyperus from Moupin in Tibet, and the
Californian Dicamptodon, all of which have the palatal teeth arranged in two
arches, with their convexity forwards, and separated by a wide space in the
middle, are likewise respectively represented by a single species. The two
remaining subfamilies, which are exclusively American, can receive only very brief
notice. In the first of these (Pletkodontince) the series of palatal teeth is trans-
verse and situated on the hinder part of the vomers ; while there are also teeth on
the parasphenoid bone ; the bodies of the vertebrae being cupped at both ends. Of
the five genera, Pletkodon, with the tongue attached along the middle line to the
anterior margin, and five hind-toes, is North American, where it is represented b}^
several species. On the other hand, the large genus Spelerpes, which has the
tongue attached only by a central pedicle, and all its edges free, ranges into
Central America and the West Indies. The fourth subfamily, Desmognathince,
differing from the last by the bodies of the vertebrae being cupped behind and
convex in front, is represented only by Desmognathus from North America
generally, and Tkorius with one Mexican species.



THE FISH-LIKE SALAMANDERS.
Family AMPHlUMlDsE.

The members of this family, which, for want of a better name, may be
collectively designated by a translation of their German title, fischmolche, differ
from the Salamandridce in the absence of eyelids. The bodies of their vertebrae
are always cupped at both ends. They are all characterised by the weakness
of the limbs in comparison to the body, and the wide separation of the front from
the hinder pair. They live chiefly or entirely in the water, and breathe by means
both of lungs and internal gills in the adult state. Only three genera are known,
the first two of which are so closely allied that it is question whether they are
really entitled to rank as distinct.

Giant The earliest record that we have of this family is a skeleton

Salamander, from the upper Miocene of Oeningeii in Basle, described by Scheuchzer
in the year 1726, under the name of homo diluvii testis; the learned doctor
believing that he had to do with a human skeleton, which, like all fossils at that
time, was considered to have been buried by the Noachian deluge. This fossil
species, which was fully as large as the existing giant salamander, together with a
smaller extinct species from lower Miocene strata near Bonn, probably belong to
the same genus. The giant salamander (Megalobatrachus maximus) was first dis-
covered in 1820 by Siebold in the rivers of Japan, but has been subsequently



FISH-LIKE SALAMANDERS.



33



obtained from China. As a genus, it is characterised by having four front and five
hind-toes, the absence of a gill-opening, and the presence of two internal gill-arches.




GIANT SALAMANDER (^ nat. size).



[The tongue covers the whole of the floor of the mouth, to which it is completely
adherent ; while the palate has a curved series of teeth on the vomers, parallel to



304 NEWTS AND SALAMANDERS.

those on the margin of the upper jaw. In form the giant salamander is very
stoutly built ; the head being very large, wide, and flattened, with the muzzle
regularly rounded, the small nostrils situated near the extremity, and the eyes
very minute. The body is likewise broad and depressed ; the legs and toes are
short, the outer ones, as well as the outer side of the hind-leg, having a mem-
branous fringe ; and the short tail is strongly compressed, with a fin above and
below, and its tip rounded. The skin, which forms a thick fold along each side of
the body, is very warty, especially on the head ; and the general colour is brown
with black spots, becoming lighter on the upper-parts. Although the ordinary
length of this salamander is about 35 inches, it is stated at times to grow to as
much as 44 inches.

Originally purchased by Siebold in the market of Nippon, the giant salamander
is now ascertained to inhabit not only the mountain streams of that island, but
likewise those of several parts of the Japanese mainland, as well as of Western
Central China. Nowhere very abundant, the creature generally frequents the
upper courses of small mountain-streams at elevations of from seven hundred to
five thousand feet above the sea-level ; some of these streams being not more than
a foot in width, and completely covered over with grasses and other herbage.
The water is clear; and usually while the full-grown salamanders curl them-
selves round masses of rock in the bed of the stream, the younger ones live in
holes. Except in search of food, which consists of worms, crustaceans, fish, and
frogs, the animals do not leave their hiding-places, and then only at night, while
they never venture on land. In confinement they are extremely slow and sluggish
in their movements, only exhibiting any marked activity when they rise to snap
at a worm or other tempting morsel. In spite of its large size, the female lays
very minute eggs, which are generally deposited in August and September. The
smallest young yet observed had a length of about 6 inches, and in every respect
resembled the adult. Probably however, at an earlier stage of development,
external gills were present ; and indeed, in an illustrated Japanese book, the young
of the giant salamander is represented with these appendages. Further evidence
of this is afforded by the circumstance that young specimens have been taken in
which the gill-openings were retained. The first two living examples were brought
to Europe in 1829 by Siebold, and were fed on fresh-water fish brought from
Japan, but when these began to fail, the male devoured his unfortunate partner.
When suitable food was procured, the male, however, flourished and increased
rapidly in size, surviving till the year 1881, when it died in Amsterdam.

Under this euphonious name is designated in its native country
Hell-Bender.

the Mississippi salamander (Cryptobranchus lateralis), which differs

from its Asiatic cousin by the presence of a gill-opening, at least on the left side of
the neck, and likewise by the presence of four pairs of gill-arches, and by the
anterior border of the tongue being free. In general form this salamander closely
resembles its larger relative; the skin being porous and rather smooth, and the
head covered with scattered wart-like tubercles. The colour is brown or greyish,
with darker blotches; but the tips of the toes are yellowish. In length this
species, which is the sole representative of its genus, reaches about 16 or 17 inches ;
and it inhabits all the tributaries of the Mississippi, and ranges into North Carolina.



FISH-LIKE SALAMANDERS.



35



In these streams it crawls or swims in a sluggish manner, seldom leaving the water,
although it can exist on land for twenty-four hours or so at a stretch, feeding
on crustaceans, worms, and fish, and being not unfrequently taken on the angler's
hook. From the circumstance that the tadpoles have never been observed, it
would seem that the larval stage must be of very short duration ; and the only
thing known about the development of the species is that the eggs are of relatively
large size. Although perfectly innocuous, the hell-bender is regarded by American
fishermen as a most noxious and poisonous reptile. It was first brought alive to
Europe in 1869, since which date it has been frequently exhibited ; and if fed on
meat or the heads of fish will rapidly increase in size, although it appears



Online LibraryRichard LydekkerThe new natural history (Volume 5) → online text (page 32 of 62)