Salamandrella keyserlingi.–The mode of propagation of this newt-like species has been observed by Shitkow near Jekaterinburg in the Ural mountains. The eggs were laid at the end of April and were deposited in bags, which were attached to a plant, with one end about an inch below the surface of the water. The bag measured 15 cm. in length and 2 cm. in width and contained 50 to 60 eggs. The larvae were hatched in 14 days in a sunny aquarium; in another with a northern aspect the hatching took 23 days. The larvae were 10 mm. long, and remarkable for the length (1 mm.) of their balancers.

Amblystoma opacum.–The general shape is very much like that of the European Spotted Salamander. The head is short and broad, the snout is rounded. The eyes are very prominent, with a black pupil and a dark-grey iris. The neck has a well-marked gular fold. The tail is thick and almost round. The hind-limbs are considerably larger than the fore-limbs. The general colour of the shiny, moist skin is a purplish-black with light grey, transverse, partly confluent bars, giving the creature a pretty appearance; the under parts are paler, bluish-grey. Total length between 3 and 4 inches, or 9 cm.

This beautiful species inhabits many of the United States east of the Rocky Mountains, from New Jersey to Florida and Texas. In the perfect state it is thoroughly terrestrial and easily kept. My specimens prefer the holes of rotten and moist, moss-covered stumps, or holes beneath stones, which they leave, at night only, in search of earthworms and insects.

A. talpoideum is closely allied, somewhat stouter and almost uniform brownish-back. According to Holbrook, "it chooses light soil in which it will bury itself in a few seconds like a mole, and there continue its course concealed from view; but its track can often be followed by the elevation produced on the surface of the soil, similar to that seen in fields infested by moles."

A. punctatum is bluish-black, with a row of roundish yellow spots on each side of the body and tail and upon the limbs.

E. A. Andrews^[53] has made observations upon the breeding of this species. Near Baltimore the eggs are very abundant in March and even in February, in small pools in the woods, but the adults are then rarely seen. Even when small pools, but 4 feet wide and 9 inches deep, were thoroughly raked out before and after the eggs appeared, no adults were found, so that it is to be inferred that the laying takes place in the night and that the adults leave the water every day to conceal themselves under stones. One female was found moving away from a bunch of eggs early in the morning. This specimen was kept isolated, and laid many eggs, and as these developed into normal larvae, the existence of internal fertilisation was proved. Previously to the laying of the eggs white spermatophores were found in the small pools, on the dead twigs and leaves covering the bottom.

A. jeffersonianum.–This very slender and slippery species, reaching a length of 6 inches, is remarkable for its long fingers and toes, and its rather compressed tail. The general colour is brown above, dirty whitish below, generally with numerous, small, light blue and pale brown spots on the sides of the neck, body, limbs, and tail. There are several colour-varieties, one of them with white specks. It is a very active and surprisingly good climber, easily escaping out of high-walled bell-glasses, hiding in the daytime in dark and moist localities. Its range extends from Indiana and Virginia to Quebec.

A. persimile.–This species is remarkable on account of its geographical distribution. It is the only non-American species, inhabiting the higher mountains of Siam and Upper Burmah. There is no doubt about its belonging to the genus Amblystoma, although it had originally been described as a Plethodon. It closely resembles A. jeffersonianum in most of its characters, notably in the arrangement of the palatal teeth, general proportions, slender toes, and even in the presence of whitish spots, which are scattered over the sides of its blackish, smooth skin.

A. tigrinum.–This, the commonest species, is conspicuous for its large, depressed head, which is as broad as it is long, its width being enhanced by the unusually large parotoid glands. The mouth is very wide. The large, prominent eyes are golden, and reticulated with brown. The gular fold is strong. The limbs are stout, the fingers and toes short. The trunk is strongly constricted by twelve intercostal grooves. The tail, which is as long as the rest of the body, is somewhat compressed laterally, but bears no trace of a fin. The general colour is more or less dark brown or bluish black, marked with numerous yellow spots and large blotches; the under surface inclines to grey. The length of the adult male is about half a foot; the females, as usual being larger, sometimes reach the length of 9 inches. The range is from New York to California and to Central Mexico.

The larva of this species is the famous Axolotl. It is provided with three pairs of delicate and much-branched external gills, a flat, long tail with a broad ventral and dorsal fin, the latter extending along the back almost to the neck. The limbs, although comparatively slender, are fully developed, and the head is much more pointed than it is in the perfect form. The larvae usually reach 8 or 9 inches in length; exceptional specimens have been recorded of one foot in length, and have been described as Triton ingens.

These larvae were found by the Spanish conquerors to occur in great numbers in the lakes near Mexico City, and were called Axolotl by the natives, a word signifying "play in the water." They were, and are still, eaten, either roasted or boiled, with vinegar or cayenne pepper.

For many years these creatures were looked upon as a species of the Perennibranchiata, under the generic name of Siredon (S. axolotl, s. pisciformis, s. mexicanus, etc.), although Cuvier suspected that they were but the larvae of an otherwise unknown terrestrial Urodele. The mystery was not cleared up until the year 1865, when some Axolotls which had been kept for a year in the Jardin des Plantes at Paris, suddenly began to pair, and laid eggs which within six months developed into full-sized Axolotls. This certainly looked as if these creatures were not larvae, but a true Perennibranchiate species. But to the general surprise several of these young Axolotls gradually lost their gills, the clefts closed up, the fins of the back and tail disappeared, the head became broader, the creatures left the water permanently, and in fact turned into the already well-known terrestrial Amblystoma tigrinum. The other brothers and sisters of the same brood remained aquatic Axolotls, which thereby revealed themselves after all as the larval and not as the perfect stage of this remarkable species.

At the suggestion of Kölliker and Weismann, Frl. Marie von Chauvin^[54] undertook, at the University of Freiburg, long and carefully conducted experiments, showing (1) that little Axolotls can comparatively easily be caused to develop further into the perfect Amblystoma if they are induced to breathe air more frequently than usual; shallow vessels, perhaps also insufficiently aerated water, will produce the desired result; (2) that the commencing metamorphosis can again be checked, the shrinking gills then undergoing fresh development; (3) that they can be forced to remain Axolotls; (4) that the cutting off of the gills has no influence upon their possible metamorphosis, the gills being easily and quickly renewed. The same lady found also that Amblystoma, the perfect form, lives in the water during the pairing time and behaves in the same way as the Axolotls.

The latest observations have been made by Metzdorff.^[55] Axolotls, at least those which are kept in captivity in Europe, are ready for propagation several times in the year, either in the spring, from April to June, or in December. The male deposits spermatophores, which in the following night are taken up by the female into the cloaca. On the following day, preferably in the afternoon, she grasps a suitable leaf, for instance that of Vallisneria, with the hind-limbs, and presses it against the vent. The eggs are expelled by strong wriggling movements of the body, and are formed into three or four packets of six to ten eggs each, so that about thirty eggs are laid at one sitting. Then she takes a rest before proceeding again; the whole process, in which the male takes no further interest, lasting about two days. The most suitable temperature is one of 18-20° C., or about 68° F. The water must be well aerated. Sterile eggs turn white on the second day. The little larvae are hatched in about a fortnight. Eggs which are kept in a higher temperature, from 22-24° C., develop more quickly, but the resulting young are smaller; they show already on the fifth day head, tail, and the beginning of the gills. According to Bedriaga, they live at first upon Infusoria and Daphnia; when they are 20-25 mm. long they eat Tubifex rivulorum; later on they take scraped meat and are liable, when hungry, to nibble off each other's gills, but these are easily reproduced. When 20-25 cm. long, at the age of about six months, they are able to breed. The chief point of interest is the fact that this species of Amblystoma frequently remains throughout life in the larval state, except that it develops generative organs. The natural causes of this retention are not completely known. According to Shufeldt, who observed them under natural conditions near Fort Wingate in New Mexico, plenty of food, the drying up of the swamps, and the increasing temperature of the diminishing water, hurries on the metamorphosis, while deeper water retards it. Weismann^[56] suggested that the specimens in the Mexican lakes which remained Axolotls were prevented from becoming perfect Amblystomas on account of these lakes, after the disappearance of the surrounding forests, having receded from their former boundaries, which are now covered with a saline, uninhabitable crust. This may be an explanation, although Axolotls do not live in brackish water. But Weismann went farther, and with his well-known dialectic powers has succeeded in spreading the belief not only that the Axolotl is a case of reversion to an ancestral stage, but that the present Amblystoma, instead of being the progressive, perfect form, is likewise a case of reversion. A reversion from a reversion! The whole line of evolution would then be as follows: Amblystoma; its young, owing to adverse circumstances, revert to the stage of the Perennibranchiate ancestors of all Urodela; if some of these Axolotls lose their gills and fins, they revert thereby into the original Amblystoma. Surely a roundabout way of explaining a curious but after all rather simple process of Neoteny; cf. p. 63.

Observations on the metamorphosis of Siredon lichenoides into Amblystoma mavortium have been made by Marsh, who also gives figures of the larval and adult forms.^[57]

Sub-Fam. 4. Salamandrinae.–The six genera of this subfamily fall into two natural groups: I, True Salamanders, with the palatal teeth arranged in a pair of S-shaped figures, and without a fronto-squamosal arch. II, Tritons, with the palatal teeth in the shape of a Λ, i.e. the right and left series meet at an angle; the fronto-squamosal arch is present, either bony, or at least ligamentous. Triton cristatus is, however, exceptional, in that the two palatal series often do not meet and that the arch is absent. The number of fingers is universally four, that of the toes is five except in Salamandrina, which has only four.

The geographical distribution of the sub-family, entirely Periarctic, may be said to be the reverse of that of the Amblystomatinae. Of the twenty-five species namely, only two are American, four are Eastern Asiatic, and of the remaining nineteen, two are Algerian, while the rest live in Europe or in Asia Minor. It is in fact an essentially Palaearctic group.

The six genera can be distinguished as follows:–

Salamandra.–Without fronto-squamosal arch. Five toes. Tail round. Three species in Europe and Western Asia.

S. maculosa.–The Spotted or Fire Salamander. General habit stout. Usual length about 5 to 6 inches; the females are mostly larger than the males; specimens of more than 8 inches in length are giants. Head as broad as it is long, snout rounded. Limbs and digits stout and short. The skin is smooth, shiny and full of pores, with a strong gular fold. The parotoid glands are large and covered with large pores. A series of distinct swellings, or cutaneous glands, each with a distinct opening, extends along either side of the back, and a shorter series along the flanks. The general colour of the Spotted or Fire-salamander is black, with irregular, large yellow patches on the back and limbs. These markings vary extremely, so much so that scarcely two specimens, collected at random, are alike. In some the yellow patches form two more or less regular bands, in others they are partly confluent; again the yellow may be preponderant on the back or much restricted. Occasionally the chrome-yellow is replaced by orange. The under surface is as a rule bluish grey-black. This combination of shiny yellow and black is a good instance of warning colours. The creature is poisonous, cf. p. 38. When left in peace, or handled gently, it is perfectly harmless, but when treated with violence, or submitted to severe pain, a milky white fluid exudes from the glands and is, under violent contractions of the muscular skin and body, sometimes squirted out in fine jets to the distance of a foot. Burning pain and subsequent inflammation result if this poison gets into the eye. The same applies to the mucous lining of the mouth and throat. A few drops of this poison introduced into the blood or into the stomach of a small animal are sufficient to cause its death. Cold-blooded animals are as susceptible as warm-blooded creatures.

I once put two American bull-frogs into the same outdoor enclosure with a large number of salamanders. Next morning the huge frogs were found dead, each having swallowed a salamander, which they were not acquainted with and had taken without suspicion.

The Fire-salamander has a wide range, namely the whole of Central, Southern, and Western Europe with the exception of the British Isles. It extends southwards into Corsica and Algeria, eastwards through Asia Minor into Syria. Where it does occur it is rather common, provided the terrain is mountainous or hilly and covered with vegetation. There it lives under moss or rotten leaves, in the roots of old trees, in the cracks and clefts of the ground, of rocks or of ruins of buildings; in default of anything better under heaps of stones, or in the holes dug by mice or moles. One chief necessity for its happiness is moisture.

The salamander does not occur everywhere, but is rather local. On certain kinds of limestone it is rare or absent; granitic terrain and red sandstone seem to suit it best, for instance the Hartz Mountains, Thuringia, and Heidelberg are favourite localities. But even there we may spend days and weeks and never come across a single specimen. We may turn stones, rake up the moss and leaves, pry into cracks, and we unearth perhaps a few sorry-looking, listless, dull and dry, half-emaciated creatures. The same place after a thunderstorm will be literally swarming with sleek, lively salamanders, in search of earthworms and all kinds of insects, especially at dusk or during the night. They disappear in the autumn, in October, to hibernate in the ground, out of the reach of frost, and they reappear again in April. Later on they congregate at little springs, always at running water, to reach which they have often to make long migrations. This is the only time when these thoroughly terrestrial creatures approach water, in which they easily get drowned.

Although this species is so common its mode of reproduction has been satisfactorily discovered only quite recently. There are some puzzling facts which it took a long time to observe correctly and to interpret. The larvae are born in April, May, or June, while there are no eggs in the oviducts, but in July these are full of fertilised eggs before copulation takes place. This seems contradictory. The explanation is as follows. In July there is an amplexus of the sexes, short, and often on land–a sort of preliminary exciting performance. Both sexes then descend into the water, but generally remain on land with the fore part of the body. The male deposits a spermatophore and the female takes part of this into its cloaca. In the case of a virgin female the eggs are fertilised in the oviduct and ripen until the autumn, but the larvae nearly ready for birth remain within the uterus until the following May, i.e. about ten months. The mother then crawls half into the water, mostly at night, and gives birth to from a few to fifty young, fifteen being perhaps the average. The young are surrounded by the egg-membrane, which either bursts before or shortly after expulsion. This species is consequently viviparous in the proper sense. If she produces a few young only, say from two to five, these are much larger and stronger than those of a large litter. Occasionally a few addled or only partly developed eggs are also expelled.

In the case of old females which have produced offspring before, the whole process is more complicated. The sperma, taken up in July, remains in the receptaculum of the cloaca until the May or June following, i.e. until the previous larvae have passed out of the uterus and are born. Then the spermatozoa ascend to the upper ends of the oviducts, where they meet and fertilise the new eggs. After these have descended into and filled the uterus, and are already developing into embryos, copulation takes place again in July, preparatory for next year's eggs.

The new-born salamanders have three pairs of long external gills, a long tail furnished with a broad dorsal and ventral fin, and four limbs, although these are small. The total length is about 25 mm. or 1 inch. The general colour is blackish with a pretty metallic golden and greenish lustre. The little creatures are very active, and at once eat living or dead animal matter. In captivity they are liable to nibble each other's gills and tails. During the first six or eight weeks they assume a row of dark spots on the sides; these spots enlarge, and the whole skin becomes darker. Yellow spots appear next, first above the eyes and on the thighs, later upon the back; the ground-colour at the same time becomes black, until at the beginning of the fourth month they look like the parents.

The metamorphosis is very gradual. The tail-fin diminishes first, but the gills grow until shortly before the little creatures leave the water. Darkness, cold, and insufficient food retard the metamorphosis, sometimes until October. It is easy to rear them artificially provided they are well fed, kept in a light place, and in clean, well aerated water. If prevented from leaving the latter, for instance when kept in a glass vessel with vertical walls, or if hindered by a piece of gauze from rising to the surface and taking in air, they can be kept as larvae well into the winter.

Very young, perfect little salamanders, of from 1 to 2 inches in length, are excessively rare; even specimens of 3 inches are far from common. They probably spend the first two or three years of their life in careful seclusion.

A few adults can be easily kept for many years in shady places provided with moss, rotten stumps and stones, to afford them suitable moist and cool hiding-places, and they readily take earthworms, larvae of beetles, snails, woodlice, etc. But any attempt to keep them in large numbers ends in failure. They congregate together in clumps, all making for the same cavity or recess, as if that were the only one in existence (very likely they are right in so far as that place is probably the best), and they get rapidly enlarging sores, chiefly on the elbows and knees. These are soon infested with fungoid growths, and this disease spreads like an epidemic and soon carries them off.

S. atra.–The Alpine Salamander differs from the Spotted Salamander by its uniform black colour and smaller size, which averages between 7 and 5 inches. It is restricted to the Alps of Europe, from Savoy to Carinthia, at from 2000 to as much as 9000 feet elevation, living with predilection near waterfalls, the spray of which keeps the neighbourhood moist, or in mossy walls, in the shade of forests near brooks, or under flat stones on northern slopes. The most interesting feature of this species is that it produces only two young at a time. These are nourished at the expense of the partially developed eggs in the uterus, and they undergo their whole metamorphosis before they are born. By far the best and most complete account of this mode of propagation has been given by G. Schwalbe.^[58] The length of the ripe embryos is about 45 mm.; they lie mostly bent up, with their heads and tails turned towards the head of the mother. The gills are beautiful, delicate red organs, the first pair being generally directed forwards and ventralwards, the second upwards, the third backwards; they are longest when the creature is about 32 mm. long, while there is still much yolk present. At this stage the gills are so long as to envelop nearly the whole embryo. There is rarely a second embryo in the same uterus, and an extra foetus is generally smaller, frequently a monstrosity not fit to live; it is probable that it is not used as food, but that it is expelled at parturition. The embryo passes through three stages, (1) still enclosed within its follicle and living on its own yolk, (2) free within the vitelline mass which is the product of the other eggs, (3) there is no more vitelline mass, but the embryo is possessed of gills 10-12 mm. in length, and is still growing. During the second stage the yolk is directly swallowed by the mouth. The walls of the maternal uterus are rather red. The exchange of nutritive fluid takes place through the long external gills, which thereby function in the same way as the chorionic villi of the Mammalian egg. Each gill contains a ventral artery and a dorsal vein, each of which looks like the midrib of a pinnate leaf; there is also a fine nerve and a weak bundle of striped muscular fibres. Each gill-filament receives a capillary artery which extends to the epithelium of the tip, where it turns into a capillary vein. The epithelium of these filaments, which are full of blood, is ciliated, the resulting current being directed from the base towards the tip. In older larvae this ciliation becomes restricted to the tips. The body of the gills is furnished with flat epithelium, these non-ciliated portions alone are closely appressed to the uterine wall, and it is here that the exchange of gas takes place between mother and larva. The nutrition takes place through the gills, as they are bathed by the yolk-mass.

Schwalbe also explains the whole question of the reduction of the number of embryos. He says rightly that in S. maculosa, which gives birth to many young, there are in the oviduct many eggs which have only partly developed into embryos, and these, perhaps from want of room and nourishment, degenerate into the irregularly shaped whitish-yellow bodies which are occasionally found packed in between the developing embryos. Consequently all those eggs had been fertilised near the ovaries. S. atra exhibits a further stage in so far as most of the eggs, fertilised above in the oviduct, degenerate, and only two or three become fully developed. These few embryos live on the degenerating eggs, which together produce the vitelline material spoken of above. The two full-grown and metamorphosed embryos, each measuring about 50 mm. in length, are equivalent to the numerous new-born larvae of S. maculosa, especially if the smaller size of the adult Alpine Salamander is taken into consideration.

Mlle. von Chauvin^[59] has experimented with the unborn larvae of this Salamander. She cut out 23 larvae and put them into water. One of them, already 43 mm. long, took earthworms on the next day, and the beautiful long, red gills became pale and shrunk, and on the third day were cast off close to the body. New gills sprouted out on the same day, first in the shape of three tiny knobs on either side. After three weeks they had become round globes, which gradually sprouted out into several branches, far shorter and more clumsy than the original gills. During the whole time the larva was lying quietly at the bottom, in the darkest corner, but showed a good appetite. The fin of the tail disappeared and was supplanted by a stronger one. In the sixth week the skin was shed in flakes, and this process took fifteen days. This larva lived in the water for fourteen weeks and grew to 6 cm. in length! When the new gills gradually shrank, the compressed and finny tail assumed a round shape, the skin became darker and shinier, and after the larva had again shed its skin, there appeared the dark rugose skin of the typical S. atra. The gills were reduced to useless appendages–not cast off–and the creature crawled out of the water. A fortnight later the gill-clefts were closed. A second larva behaved similarly, first casting off the feathery gills, substituting a new and stronger set, which, however, fourteen days after excision from the uterus, shrank again, and on the nineteenth day the gill-clefts were closed. The lady also observed that nearly ripe larvae, when cut out, rushed about in the water and ate, just like the new-born larvae of the Spotted Salamander.

A third species, S. caucasica, is found in the Caucasus. It rather resembles the Spotted Salamander in coloration, but has a larger tail and lacks the lateral warts. The male is remarkable for the possession of a soft permanent knob or hook at the top of the root of the tail. This pommel possibly prevents the slipping off during the amorous amplexus, provided the sexes then entwine like certain Tritons.

Chioglossa lusitanica.–The only species of this genus is restricted to the north-western third of the Iberian peninsula. This graceful, slenderly-proportioned and beautiful Salamander is apparently very rare and local, having hitherto been found at a few places, namely, near Coimbra, Oporto and Coruña. It lives under moss, and runs and climbs with an agility surprising in a Urodele. The tongue is long, ending in a fork, and is supported by a median pedicle so that the tip can be quickly protruded to the distance of more than an inch. The whole length of the animal is about 5 to 6 inches, two-thirds of which belong to the long tail, which is compressed at the end. The skin is smooth and shiny, with a gular fold and large parotoids. The general colour is a rich dark brown, with a pair of broad reddish-golden bands along the back and tail, the bands being separated by an almost black vertebral line.

The few specimens which I have been lucky enough to observe made little holes or passages in the moist moss of their cage, peeping out with their heads in wait for little insects, which they caught with flash-like quickness. They seem to be crepuscular.

Salamandrina perspicillata.–This genus, represented by one species, a native of Liguria and Northern Italy, possibly extending into Dalmatia, is the only Salamander which has but four toes. The skin is not shiny and smooth, but is finely granular and dry, forms no gular fold, and is devoid of parotoid glands. The tail is more than half the length of the animal, which measures from 3 to 4 inches. The general colour is black-brown with a broad V-shaped orange-yellow mark extending from eye to eye over the occiput. A faint irregular yellowish line extends along the middle of the back and tail. The throat is black, with a diffused white patch in the middle; the belly is white, with black dots; the anal region, the inner sides of the legs and the under side of the tail are carmine-red.

This slender and pretty Salamander is diurnal, and feigns death when discovered. Only the female goes into the water, in March, to glue the eggs on to submerged rocks or water-plants. The young finish their metamorphosis by the month of June, and reach full size during the winter, the climate of their home being sufficiently genial to make hibernation scarcely necessary.

Triton s. Molge.–The tail is strongly compressed and frequently has a permanent fin. The fronto-squamosal arch is variable, it being either bony as in the South European, Eastern and American species, or reduced to a ligament, or lastly absent as in T. cristatus. The males of all the English Newts, of T. vittatus and of T. marmoratus, develop a high cutaneous crest on the back and tail during the breeding season, and this crest acts not only as a swimming organ and ornament, but also as a sensory organ.

The whole genus comprises some eighteen species, twelve of which are European, although some of these extend into Western Asia; T. pyrrhogaster and T. sinensis are found in N.E. China, the former also in Japan; T. poireti and T. hagenmuelleri live in Algeria, and only two, T. torosus and T. viridescens, are North American. Some of the species have a limited range; thus T. montanus is confined to Corsica, T. rusconii to Sardinia, T. boscai to the north-west of the Iberian peninsula and T. asper to the Pyrenees.

Newts all prefer moisture without heat. During the pairing season they take to the water, mostly to stagnant pools, which sometimes implies long migrations. During this period, which is in some cases rather prolonged, they become thoroughly aquatic and undergo some important changes. The tail-fins are much enlarged; in the males of some species a high cutaneous fold grows out on the back, devoid of muscles, but rich in sense-organs. The whole skin, instead of being dry, possesses numerous mucous glands and, what is of more importance, specialised sensory apparatuses which are arranged chiefly along the lateral lines of the body and part of the tail.

After the breeding season Newts become terrestrial, hiding in cracks, trees, or in the sandy soil. Some species aestivate during the hot and dry season. They hibernate either in the ground, or occasionally in ponds. T. vulgaris is difficult to keep in the water beyond the pairing season, while this is easily done with T. alpestris and T. cristatus; T. waltli can live in the water for years. The food consists of all kinds of insects, centipedes, worms, snails, etc., which are searched for chiefly at night. It is astonishing to see a little Triton getting hold of and gradually swallowing a wriggling earthworm almost as thick and as long as itself. When two newts seize the same worm, as these voracious and jealous creatures often do, each gets hold of one end, and swallowing as much as it can, twists and rolls round in a direction opposite to that of its rival, until the worm breaks, or until the jaws of the two newts meet and the stronger of the two draws it out of the weaker one and swallows the whole worm. They do not drink, but soak themselves in the water.

The skin is shed periodically, and rather often by the rapidly growing young; by the adult, during the life in the water, rarely during the sojourn on dry land. The skin breaks round the mouth; assisted by the fingers and by contortions of the body, it is then slipped backwards over the trunk and tail, whereupon the newt seizes the skin with the mouth, draws the shirt off entirely, and–swallows it. Such freshly shed skins are very delicate and pretty objects when suspended in water or some preserving fluid. The shed skin, consisting only of the outermost layer of the epidermis, is entire, but turned inside out, with fingers and toes complete, the only holes being those for the mouth, eyes, and vent.

None of the Tritons are viviparous. The eggs, which are glued singly or in small numbers on to stones or water-plants, are hatched in about a fortnight, sooner or later according to the species and the prevailing temperature. The larvae are always provided with three pairs of branched external gills; the fore-limbs appear much earlier than the hind-limbs. Most, perhaps all, larvae develop two pairs of thread-like protuberances on the sides of the upper jaw, by means of which they attach or anchor themselves on to water-plants shortly after they are hatched. Thus moored they remain motionless in a slanting position, now and then wriggling their tails and shifting their place, or sinking to the bottom. The metamorphosis is finished during the first summer, and the little newts, often partially transparent, leave the water to hide under stones. Not unfrequently the metamorphosis is retarded and not finished by the autumn. The larvae of T. cristatus, especially when reared in ponds with abrupt or overhanging banks, so that they cannot leave the water, retain considerable remnants of the gills, still more frequently the clefts, although breathing chiefly by the lungs. Such individuals reach a length of 3 inches, and are larvae so far as the finny tail and the gills are concerned. They hibernate in this condition, and in exceptional cases reach sexual maturity;–at least the females, which develop ripe eggs; the males are not known to produce spermatozoa.

Much has been written on the amorous games of newts, but it is only recently that the mode of fecundation has been actually observed. Gasco^[60] placed the newts in glass vessels suspended from the ceiling of his laboratory. The antics of the enamoured male around the female, rubbing the latter with its head, or lashing it gently with the tail, and playing around it in its often beautiful nuptial dress, are meant to excite the female. The male then at intervals emits spermatophores, which sink to the bottom, and the female takes them up into its cloaca. For further information see p. 54.

Triton cristatus.–The Crested Newt has a slightly tubercular skin with distinct pores on the head, on the parotoid region and on a line along the side of the trunk. There is a strong gular fold. The general colour above is dark or black-brown with an olive tinge, interspersed with darker spots; the sides of the body bear irregular white spots. The under parts are yellow, almost always with large black spots. The iris is golden yellow.–The nuptial dress of the male is very striking. A high, serrated crest occurs on the head and body; the upper surface of the head is marbled with black and white; the under parts are orange-yellow with black spots, and the sides of the tail are adorned with a bluish-white band.–The female, always devoid of a crest, generally exhibits a yellow line along the middle of the back.–The average length of fully adult specimens is about 5-6 inches or 13-15 cm.; the females are as usual larger than the males; 144 and 162 mm. for an English male and female respectively are exceptional records.

Propagation takes place in April. The newly hatched larvae are yellowish-green, with two black dorsal bands, and with a whitish edge to the tail-fin. By the middle of July they are about 5 cm. long, and the white-margined tail now ends in a thread 1 cm. in length. The general colour above is light olive-brown, dotted with black; the flanks and belly have a golden shimmer.

The Crested Newt has a wide distribution, extending from England and Scotland through Central Europe into Transcaucasia; the northern limits are Scotland and Southern Sweden. Although found in Greece and Lombardy, it does not occur in the Iberian peninsula nor in the South of France, where it is represented by the next following species.

Triton marmoratus.–The Marbled Newt is of the same size as the Crested Newt. Its ground colour is grass-green above, brown below, with numerous large and small irregularly shaped marbling patches, spots and dots of black. The crest of the neck and trunk is entire, not serrated, adorned with dark vertical bands, and separated from the high dorsal fin of the tail by a deep indenture or gap. The female has an orange line, slightly sunk in, instead of the crest. This newt is confined to France and the Iberian peninsula. In the North of Portugal and in Galicia it is frequently seen in little streams and ponds during the months of March and April. The rest of the year it spends on land. In France occur hybrids of this species and T. cristatus. They have been described as T. blasii.

T. alpestris.–The Alpine Newt is easily distinguished by the rich orange colour of its under parts, which are unspotted, excepting a few dark specks across the throat, below the gular fold. Specimens with many ventro-lateral black spots are exceedingly rare. All the upper parts are dark, but vary individually. The prettiest specimens are dark purplish grey, with black marblings; others incline more towards brown ground-tones, the blackish markings then appearing more prominent. The sides are often stippled with tiny whitish dots. The iris is golden yellow.–The nuptial male has a low, not serrated crest, which extends uninterruptedly from the nape into the dorsal fin of the tail. The crest is pale yellow, with black vertical bands and spots. The ground-colour of the upper parts inclines to blue, especially on the sides. The lower fin of the tail assumes an irregular band of bluish-white confluent patches.

This newt is rather small, females rarely exceeding 100 mm. or 4 inches in length. Its home is chiefly the hilly and mountainous parts of Central Europe, from Holland to Lombardy, Austria-Hungary, and Greece. Although it ascends the Alps to between 6000 and 7000 feet, it is also found in the Netherlands, but not in the North German plain.

T. vulgaris (s. taeniatus, s. punctatus).–The Common or Spotted Newt usually reaches 3 inches (7-8 cm.) in length. Boulenger's record-specimen measured 104 mm. It is characterised by the yellow, partly orange under surface, which is always spotted with black. The upper parts are olive-green or brown, inclining to white on the flanks; the black spots of the back, sides, and especially of the tail, are arranged in more or less distinct lines, giving a somewhat banded appearance to some females.–The breeding dress of the male shows a non-serrated, but "festooned" high and very wavy crest, which extends from the neck without interruption into the likewise wavy tail-fin. The tail is adorned with a lateral, glittering blue stripe, interrupted by vertical dark spots. The larvae are marked by a series of yellow dots, which extend over the lateral line and the tail, which latter temporarily possesses a terminal filament like that of the larvae of T. cristatus.

The distribution of the Spotted Newt is the same as that of T. cristatus, namely Europe with the exception of the Iberian Peninsula, and Western Asia.

T. palmatus s. helveticus.–This is the smallest of all the European newts, rarely reaching more than 3 inches in length. It is distinguished by several specific characters. The tail ends in a thread which is in some males 10 mm. in length, but is only just indicated in the female. The breeding male develops a cutaneous fold along each side of the back, and a low, entire, vertebral crest; the toes are fully webbed. The under parts are pale yellow, inclining to orange towards the middle of the belly, and with a few blackish dots. The lower caudal crest has its edge blue in the male, orange in the female. The general colour of the smooth skin is olive-brown above, with numerous dark spots, which are arranged in more longitudinal streaks on the head.

The Webbed Newt is a native of Western middle Europe, ranging from Great Britain and Northern Spain to Switzerland and Western Germany.

Closely allied to the last species are T. boscai of Spain and Portugal, T. italicus, T. montadoni of Moldavia, and the beautiful T. vittatus of Asia Minor. From China and Japan are known T. pyrrhogaster and T. sinensis.

The North American species are T. torosus and T. viridescens. The former, of Western North America, is one of the largest newts, reaching a length of more than six inches. The head is much depressed and broad, and has very prominent parotoid and other glands. The limbs are strong, especially in the male. The skin of the upper parts is very granular, uniform dark brown, without a crest. The tail, which is larger than the head and body, is strongly compressed, with a low dorsal and ventral fin. The under parts and the lower edge of the tail are uniform yellow or orange red. The iris is green. A specimen in my keeping spends most of its time in the cracks of rotten stumps or on the top of moss in the darkest shade. It lives on earthworms but despises insects. Like most of the other newts it becomes lively at dusk.