Grass Snake (Tropidonotus natrix, Linn.).

Before entering upon a description of the greatly feared though harmless Grass, Ringed, or Common Snake, it would be well to say a few words on the structure of Snakes in general, and so avoid some amount of repetition, for in a general way our three species are alike.

The Slow-worm, our legless Lizard, affords a convenient transition to the Snakes; but the bony skeletons of Snake and Slow-worm exhibit considerable differences. No Snake possesses a breastbone, bladebone, or collarbone, so that all the ribs are free at their ends, and they are strongly curved to produce the cylindrical form of body. When bulky food is taken the ribs can be flattened out to allow of the necessary distension of the body until digestion and muscular pressure have reduced the bulk. The bones of the skull are connected so loosely that the head can be flattened and widened, so that the mouth can admit prey equal to three times the size of the Snake's head under normal conditions. To assist in the swallowing of such large bodies, the two halves of the lower jaw have no bony connection but are united instead by elastic ligaments, so that each half can be moved independently of the other, and by the alternate movement of the two sides with the teeth all pointing backwards the food is worked back to the throat. There are other teeth on the roof of the mouth which make it difficult for living prey to struggle forward and escape when once it has been seized. The teeth are all thinly coated with enamel, and are not planted in sockets. If they should get broken by the severe work imposed upon them, they are soon replaced by others which lie in reserve. Poison fangs are much larger than ordinary teeth, and the enamel is folded so as to produce a groove down which poison is pressed from a gland into the wound made by the point of the fang. The fang is hinged at its base and ordinarily lies pressed back upon the upper jaw, and is only "erected" when the Snake is prepared to strike.

Externally the Snake is covered by small overlapping scales on the upper parts and by broad plates on the under surface. The head is covered mainly by shields, each of which has a definite name, but for the purposes of this book it is not necessary to enter upon a tedious recital of these terms, beyond giving them for reference under the diagram of a Snake's head.

The eyes of a Snake are always wide open, for there are no movable eyelids to close them. The eyeball has slight power of movement under its transparent cover, which protects it much as the watch-glass protects the delicate hands of the watch. As in the Slow-worm, there is no external indication of ears, though these are present under the scales. The very long and slender tongue divides forwards into two branches, and when not in use is drawn into a sheath at its base. It is constantly used to ascertain the nature of things by contact, and for this purpose is protruded through a little gap in the front of the upper jaw. The gape of the mouth extends far beyond the eye. The forward extremity (glottis) of the wind-pipe can be thrust outside the mouth when, owing to the passage of a bulky victim, there is danger of obstruction by compression.

The British Snakes represent the two families ColubridÆ and ViperidÆ.

Every summer and autumn our daily newspapers afford evidence that on the subject of Snakes the average man has not advanced in knowledge beyond that of his prototype a thousand years or so back. With all that has been done in various ways during the last half-century to spread knowledge of natural things, it is astonishing that editors should admit scare reports about Snakes without a line to set the reader right. Internal evidence shows that nine-tenths of these alarming reports about poisonous and aggressive Snakes refer to the innocuous Grass Snake. This is the kind of thing that reflects the vaunted intelligence and calmness of the average Briton:—

"An enormous snake was killed yesterday at ——, only a few yards from where some children were playing. The Rev. Mr. Blank courageously seized the reptile behind the head, but when it hissed savagely at him he was forced to throw it down. Its head was then smashed with a pole, and finally it was despatched with the aid of a spade. The venomous monster was found to be over three feet in length. Its nest was found and a large number of eggs destroyed."

A very elementary knowledge of our native snakes—such as all country folk might be expected to possess—would dispose of all this fear and sensation, for no one has ever found a Viper or Adder—our only venomous snake—that measured quite as much as three feet, or that had a nest of eggs.

The Grass Snake is our largest British species, full-grown females averaging four feet in length; the males a foot less. Exceptional examples are little short of six feet, and in Italy the same species attains to a length of eight feet. It is of graceful form, the body tapering gently from its middle to the very slender tip of the tail. The long, narrow head, covered with large shields, ends in a blunt snout, with eyes and nostrils at the sides. The rather large eyes have round pupils circled with gold and a dark brown iris. Just behind the head there are two patches of yellow or orange (sometimes white) forming a bright collar which serves to indicate this species at a glance. In large females this collar is sometimes missing. Immediately behind it are two patches of black, often united in the middle line, and behind these the ground colour of grey, olive, or brown is uniform to the tip of the tail. Upon the ground colour of the back are laid two rows of small blackish spots, and a row of short vertical bars along each side. The underside, which is covered with broad plates, is chequered in black and white (or grey); but is sometimes entirely black. The tail accounts for about one-fifth only of the total length.

Apart from the head-shields and the broad plates of the underside, the Grass Snake is covered with nineteen rows of small, overlapping, lance-shaped scales with a central ridge or "keel." These scales are an outgrowth from the skin, and when the Snake moults they do not fall off as the hairs of fur-clad animals do, but the entire skin with its scales is cast intact. It separates first at the edges of the jaws, and the Snake pushes against the ground, stones, or plant stems until the loose skin is behind the head. Then it glides out of the remainder, reversing it in the process. In these discarded sloughs the lens-like covering of the eye will be found unbroken.

In the autumn the Grass Snake retires to some safe shelter under the roots of trees, among the stubs of a coppice, under a brushwood pile or fernstack, in order to pass the winter in sleep. As a rule, several or many associate in hibernation, and when found they are usually twined together in intricate knots. Here they remain until March or April, when the Frogs, Toads, and Newts, emerging from a similar retirement, are available for a good meal. About this time the males seize the females in their jaws, and with their bodies entwined pairing takes place. Some time between June and August the female seeks some convenient mass of fermenting vegetable matter amidst which to burrow and deposit her eggs. If a heap of fresh stable manure is available she will prefer it, the heat hastening incubation. The eggs—which may number a dozen or anything up to four dozen—are equal-ended ovals with a tough, parchment-like shell, and all connected in a string. As soon as laid they begin to absorb moisture from their surroundings, and increase in size until they are about an inch and a quarter in length. They hatch in from six to ten weeks, according to temperature, and the baby Grass Snakes measure from six to eight inches. Before hatching they are provided with a special egg-tooth projecting from the front of the jaws, which enables them to pierce the egg-shell. It soon becomes loose and drops off after its special function has been performed. The young Snake sheds its skin before taking its first meal, and thereafter goes through the same process four or five times in a year.

The Grass Snake appears to have a life comparatively long. The female is about four years old, with a length of two feet, before she begins to breed. Gadow mentions a fine female which he had alive for nine years, and during this period her length increased from thirty-five to forty-two inches.

Although the Grass Snake may be found frequently about ponds and ditches where there are Frogs, Toads, and Newts to be caught, it is by no means restricted to such resorts, but may be met with on chalk hills, sandy heaths, and other places far removed from water. In addition to the amphibians mentioned, it feeds occasionally on fish, mice, and small birds. The young Snake takes worms, tadpoles, and the young of newts, frogs, and toads. It swims well and often enters the water to obtain its prey. Although an agile reptile, it may be caught without difficulty where the ground is not too rich in mouse runs or too well covered with furze. The undulations by which it progresses are always horizontal, not vertical as sometimes represented by imaginative artists. When captured it seldom makes any attempt at biting, though it will hiss freely and snap its jaws. It usually seeks rather to disgust its captor by the voiding of a fetid secretion with a strong odour of garlic among other objectionable scents. It soon becomes gentle and tame.

The Grass Snake is widely distributed over England, Wales, and the south-eastern parts of Scotland. It appears never to have reached Ireland. Various attempts have been made to introduce it in the latter country, but the prejudices of the people and their respect for the legendary miracle of their patron saint have always prevented the Snakes from establishing themselves.

Smooth Snake (Coronella austriaca, Lacepede).

Although in general appearance similar to the Grass Snake the Smooth Snake in the hand exhibits a sufficient number of differences to make its identification easy. The smoothness which gives it a name is at once evident to our sense of touch, and is due to the fact that all its scales lack the little keels or ridges that give a certain roughness to the common species. It never attains to so large a size as the Grass Snake, its maximum length being two feet.

The ground colour of this snake on the upper side is grey, brown, or reddish, with small black, brown, or red spots, which are usually in pairs; occasionally there are three lighter longitudinal stripes. The upper part of the head is sometimes blackish; this is more frequently so in young examples. A dark streak runs from the nostrils and through the eye to the angle of the mouth. This streak may be prolonged, even to the tail. On the underside the colouring is some tint of orange, red, brown, grey, or black, with or without black spots or dots. The eye has a round pupil like that of the Grass Snake, and this helps to give it a similar gentle appearance.

Prior to the year 1853 British specimens had been regarded as mere variations of the Grass Snake, but in that year it was captured by Mr. F. Bond at Ringwood by the New Forest, though it was not recorded under its proper name until six years later. It has been found since in other parts of Hampshire, in Dorset, Surrey, and Berkshire; in some places abundantly, especially those in which the Sand Lizard occurs, this being the Smooth Snake's favourite prey. Its usual resorts are heaths, stony wastes and wooded hillsides. Its food consists mainly of Lizards, but it also takes young Snakes and Slow-worms; occasionally it consumes mice and mice-like mammals including the Voles and Shrews. When these are sufficiently large it is said to coil around them in Boa-constrictor fashion.

Pairing takes place soon after emergence from hibernation in spring. As in the case of the Slow-worm and the Common Lizard, the eggs are retained until the young are ready to hatch out, and they are born about the end of August. They vary in number from two to fifteen, but usually there are about six to a birth. They are enveloped in a thin membrane which is ruptured immediately, and the Snakes are seen to be about five or six inches in length.

Like the Grass Snake this species emits an objectionable odour when captured, and at first attempts to bite, but this unfriendly phase passes quickly, and it becomes perfectly tame and exhibits a considerable amount of intelligence.

It may be as well to add that, if we count the rows of small scales on the back and sides of either of our non-venomous Snakes, we shall find there are nineteen of them. In the Viper there are twenty-one rows—rarely nineteen or twenty-three. Each one of these scales is marked with a tiny pit which appears to coincide with the end of a nerve fibre, so that one may say the sense of touch resides in every separate scale. The head is less distinct from the body than is the case in the Grass Snake; and the slender tail is one-fourth of the entire length in the male and one-sixth in the female.

The Smooth Snake is found throughout the greater part of Europe.

Viper or Adder (Vipera berus, Linn.).

At a superficial glance the Viper is quite distinct from our other Snakes. Instead of the long, gracefully tapered body of these, the Viper is short and thick in the body with a short tail. So far as the length is concerned, the average Viper is less than two feet. A few exceptionally large females have been recorded measuring two feet eleven inches; but the female is always slightly longer than the male—usually about an inch more. Two feet three inches may be regarded as the ordinary maximum for a female. The head is flatter above, and it broadens behind the eyes, so that it is very distinct from the body; further, the shields on the head are very much smaller than the corresponding plates of the Grass Snake. The iris of the eye is coppery-red, and the pupil is vertical—which usually denotes nocturnal habits, but the Viper is active by day as well as by night, and is fond of basking in the sunshine.

Respecting colour, there is a considerable range of variation, much of it sexual; but, generally speaking, it may be said to be some tint of brown, olive, or grey, and this ground colour may be so dark that the darker markings are scarcely perceptible on a cursory view. Along the sides there are whitish spots, sometimes reduced to mere dots. The brown, red-brown, or olive males have black markings; the grey or whitish males are marked with brown or black, and have the underside black. The throat is black, or whitish with scales spotted or edged with black.

The females if brown or brick-red have dark brown or red markings; olive females have brick-red bands or spots. The yellowish-white chin and throat are sometimes tinged with red. The eyes of the female are smaller than those of the male.

The markings are subject to a good deal of variation as well as the ground colour. The usual wavy or zigzag line down the centre of the back, with a series of spots on either side, may be broken up into oval spots; and the characteristic pair of dark bars on the head may form either a ? or an ?. The broad shields which cover the lower surface may be grey, brown, bluish, or black, or bluish with triangular spots of black, sometimes with white dots along the margins. Below the end of the tail the colour is yellow or orange. Specimens have been recorded almost entirely of a rich black, the excepted portion being the whitish underside of the head and throat.

The usual haunts of the Viper are sandy heaths, dry moors, the sunny slopes of hills and hedgebanks, bramble clumps, nettle beds, heaps of stones and sunny places in woods; but we have also found it in heathy and grassy places that were distinctly and permanently wet. For food they appear to prefer small mammals such as mice, shrews and voles, young weasels; but also take birds, lizards, slow-worms, frogs, newts, and large slugs. The young subsist for a time on insects and worms.

The Viper retires in autumn to a hollow under dry moss among the heather, under faggot stacks or into the discarded and leaf-covered ground nests of birds. They reappear about April, and may then be seen coiled on a sunny bank, apparently more concerned to absorb heat than to find food. They pair at this season, and the young (varying from five to twenty) are born in August or September. In this species, again, the eggs are retained until fully developed, and when the young see the light they are coiled up tightly in a thin, transparent membrane, which usually breaks during the process of birth. They measure from six to eight inches, and are at once independent.

The hoary old legend about the mother Viper opening her jaws to afford sanctuary to her young in time of danger has probably arisen from some occasional acts of cannibalism. It presupposes what is not true of any of our reptiles—that the young remain with their parent. They all begin life equipped for independence, and act accordingly.

The Viper is not so amenable to a life of captivity as our other Snakes. It is not amiable, indeed its temper may be described as short and sulky, which it displays by refusing all offers of food; most captive Vipers die of starvation, the "hunger strike" being their effective protest against the deprivation of liberty. On being captured they are always ready to bite; but in a state of freedom the Viper is not the aggressive monster that is popularly supposed. It seems to depend largely upon its inactivity for escaping observation, but when it knows it has been discovered its immediate impulse is to seek cover. Accidents from Viper bites are rare in this country, where people go about well shod, and there are very few cases of authenticated death from this cause. On the Continent, however, such cases are frequent; and it is suggested that in the warmer parts of Europe, where bare feet are more numerous, the Viper's venom may also be more active than it is here. It is the toes or fingers that are most likely to be bitten, for the Viper's mouth is not large enough to enable it to bite the larger parts. The mechanism by which the poison is introduced into the blood of its victim has been briefly described on page 146.

It must not be supposed from the foregoing remarks that we deprecate caution in dealings with the Viper; but we do desire, if possible, to dispose of that senseless fear that is unworthy of man. If the victim is in bad health the bite of the Viper may involve very unpleasant consequences—even death, but this is much more likely to follow from the sting of a gnat! In case of a bite from this species, the approved treatment is to suck the wound thoroughly and apply oil to it. The rustic remedy approved by quack doctors is an oil prepared from the Viper's own fat—"a hair of the dog that bit you" sort of cure. A ligament above the wound will prevent the poison spreading; and the blood may be made alkaline by the internal administration of ammonia. The popular idea in many parts is that the reddish-coloured Vipers have more virulent poison than the others, but there does not appear to be any good grounds for this differentiation.

The Viper is found in all parts of Britain, but is not known in Ireland.