OPHIDIAN TASTE FOR BIRDS’ EGGS.

CAN we correctly say that snakes have a ‘taste’ for eggs? What flavour can there be in an egg-shell, and what pleasure or gratification can a snake derive from swallowing a hard, round, tasteless, apparently odourless, and inconvenient mass like a large egg?

That snakes do devour eggs and swallow them whole, though the fact is often questioned in zoological journals, is well known in countries where snakes abound. Therefore, we are led to consider by what extraordinary insight or perception a snake discovers that this uncompromising solid contains suitable food? Avoiding, as snakes do as a rule, all dead or even motionless food, it is the more surprising that eggs should prove an exception. And not merely the small and soft-shelled eggs of little birds, that can be got easily into the mouth and swallowed, but the eggs of poultry and the larger birds, which must in the first place be difficult to grasp, and in the second place to which the jaws so wonderfully adjust themselves that the egg passes down entire into the stomach.

Many snakes which do not habitually live in trees, will climb them in search of birds’ eggs; and many others, not so agile in climbing, consume vast numbers of eggs from the nests of birds which build upon the ground. In countries where snakes are numerous and population sparse, their depredations in the poultry-yards of secluded residences are of common occurrence. And it is a noteworthy fact that the crawling culprits possess an excellent memory for the localities of hens’ nests, so that when once the eggs have been missing, and the snake’s tracks discovered, the farm-hands well know that the offence will be repeated, and watch for the thief, to whom no mercy is shown. But between their virtues as mousers and their vices as egg-thieves, an American farmer does sometimes hesitate in destroying certain non-venomous snakes, and may occasionally feel disposed to save his crops, to the sacrifice of his wife’s poultry-yard.

A gentleman, long a resident in India, informed me that a cobra once got through a chink into his hen-house, and ate so many eggs from under a sitting hen, that it could not effect its exit through the same chink, and so remained half in and half out, where the next morning it was discovered in a very surfeited condition. It was immediately killed and cut open, when, as the eggs were found to be unbroken and still warm, the experiment was tried of replacing them under the mother, who in due time hatched the brood none the worse for this singular ‘departure’ in their process of incubation.

In another poultry-yard a cobra was found coiled in a hen’s nest, from which all the eggs were gone but two. In this case, also, the snake had swallowed more than it could conveniently manage, but either alarm, capture, or greediness so impaired its digestion that all the eggs were ejected entire!

A similar incident was recorded in the Field newspaper, in May 1867, the editor introducing the narrator as one of undoubted intelligence and veracity.

His gardener informed him that a cobra had attacked a guinea-fowl’s nest in the compound. He took his gun and repaired immediately to the spot, where he saw the cobra making off, followed by a host of screaming fowls. The gentleman shot the culprit through the head, and then observed a tumour-like swelling, as of an egg recently swallowed. The gardener cut the reptile open, and took out the egg safe and sound. The gentleman marked the egg, and set it with fourteen others under a guinea-fowl. In due time the young chick was hatched; and this he also marked, in order to observe whether it would grow up a healthy bird, which it did.

Several other well-authenticated instances of this nature might be related; but those who have friends or relatives in India are no doubt sufficiently familiar with such stories to dispense with them here.

Aware of a cobra’s penchant for eggs, the snake-catchers, or those who pack them for transportation to Europe, sometimes place a supply in the cages, as convenient food for the snakes during the voyage. The keeper of the Ophidarium[7] at the London Zoological Gardens frequently finds hens’ eggs unbroken on opening a case containing the newly-arrived cobras. How many eggs were originally in the box, and how many had been eaten and digested, or reproduced during the voyage, it would be interesting to ascertain if possible.

Snakes are fastidious feeders and long fasters during confinement. Those cobras may have fasted during the whole journey, or they may have swallowed and disgorged the eggs through terror, like their friends at home. Two things are clear, viz. that the eggs were deposited in the cage as a favourite delicacy, and that a hen’s egg is not a too cumbrous morsel for even the small-headed cobra to manage.

A gentleman, accustomed to snakes, on hearing of this, regarded the eggs found intact in the box as a proof against their egg-eating propensities, and pointed to the Ophiophagus which, for lack of his ordinary food one winter, had in vain been tempted with both pigeons’ and hens’ eggs. ‘He won’t eat them, he won’t notice them,’ was the keeper’s testimony; but, then, other snakes often decline food, even their habitual and favourite food, when in confinement; and so far as the Indian snakes are concerned, their egg-eating habits are confirmed by many writers, including Sir Joseph Fayrer, who affirms that ‘they will eat and swallow the eggs whole.’ ‘Snakes are all carnivorous, existing on animals and birds’ eggs,’ he again remarks.[8] ‘Cobras rob hen-roosts, and swallow the eggs whole.’[9]

And does not the very fact of the eggs being placed in the cages by the natives for their food during a journey, show that these latter knew what would be most likely to tempt them?

The Indian vernacular of the Ophiophagus is Sunkerchor, which means, as Fayrer tells us, ‘a breaker of shells.’ I have taken some pains to ascertain a more definite reason for this name being assigned to the Ophiophagus, or snake-eater, but without success. Is it because he is an exception to the rule of eggs being swallowed whole, he having for his size a particularly small mouth and swallow; and that he, like his relatives the cobras, being unwilling to relinquish the dainty, manages them clumsily, and breaks the shells? There must be some reason for his being known as the ‘shell-breaker.’

Being a tree snake, it may be that ‘Sunkerchor,’ the shell-breaker, attempts the smaller birds’ eggs, which are too tender to be swallowed without fracture.

The cobra-worshipping HindÛs on their festivals place eggs for their gods, that they also may partake of the feast.

But examples of egg-eating snakes are not confined to India. America, the Cape colonies, and all snake countries are prolific of them.

Mr. P. H. Gosse in Jamaica killed a yellow boa (Chilobothrus inornatus), inside of which he found seven unbroken hen’s eggs. It had been caught in a rat trap.

Catesby, the early American naturalist, in describing the corn-coloured snake, says ‘it is harmless except as a robber of hens’ roosts.’ Lawson, the still earlier traveller, in his quaint description of the ‘Racer,’ or ‘black snake’ (Coluber constrictor), says:—‘He is an excellent Egg Merchant, for he does not suck the Eggs, but swallows them whole. He will often swallow all the Eggs from under a Hen that sits, and coil himself under the Hen in the nest, where sometimes the Housewife finds him.’ Lawson, also, describes the ‘Egg and Chicken Snake’ (a doubtful vernacular), ‘so called because it is frequent about the Hen-Yard, and eats Eggs and Chickens.’ The early American settlers guarded their poultry-yards against snakes as vigilantly as against rats, foxes, and other such predators. As for the ‘black snake,’ though non-venomous, all rearers of poultry visit him with vengeance.

Often in our rambles through the woods in Virginia we saw these snakes, and the swiftness with which they would vanish through the grass like a flash of steel, proved how well they merited their name of ‘Racer.’ These are the ‘black snakes’ par excellence, in distinction to the black water-viper and several other kinds which have more or less black about them. Sometimes they lay basking in our path, probably after a meal, when they become sleepy and inactive. On one such occasion I had an excellent opportunity of examining one of them, and of measuring it. It was exactly six feet long, and in the largest part as thick as a man’s arm. Its scales were beautifully bright, like an armour of steel, the white throat and pale under tints completing the resemblance of polished metal. It was sleeping on a soft carpet of moss and grass which bordered our sandy path, and which showed the Racer to great advantage. My young companion, a Virginian boy to whom no sport came amiss, espied it with delight, and ran to pick up a stout stick. Knowing that it was harmless, and so excellent a mouser, I pleaded for its life; for in truth the nocturnal visitors in the shape of rats at our country dwelling were so noisy and numerous, that I regarded the Racer as a friend rather to be encouraged and domesticated than ruthlessly slain. Its couch now, in its spring green and freshness, was enamelled with the star-like partridge-berry (Mitchella repens), dotted here and there with twin coral berries that had lingered through the winter; the bright-leaved, white-flowered winter green (Chimaphila maculata); the Bluets (Oldenlandia purpurea), and other exquisite little flowers too lovely to be crushed and tainted; while a sunbeam glancing through the trees, and showing up the polished scales of the unconscious Racer, all seemed eloquent with mercy.

It was the first time I had been close enough to touch so large a snake; and the whole scene is vividly before me now. Culprit though it might be, it was splendid and beautiful; and I entreated Johnny to wait and wake it up, so that we might watch its actions.

‘All very fine!’ cried the boy, not yet in his teens, ‘and fourteen more eggs gone from the hen-house last night!’

So he pounced upon a fallen bough, which he rapidly trimmed to suit his purpose, then with one sharp blow across the poor thing’s back, disabled it. I think the snake was quite killed by the blows the boy subsequently dealt, for I do not remember that it moved at all.

‘Now you can look at it as much as you please,’ said the juvenile sportsman as he straightened the reptile out to its full length. Then I examined and measured it, and found it was more than two lengths of my long-handled parasol. Black creatures with two hands and two legs were far more likely to be the egg-stealers than that poor Racer far off in the woods.

This ‘black snake’ climbs trees with ease, and hangs from a branch to reach a nest below him. ‘He is the nimblest creature living,’ says an old writer on Virginia, for he not only has the credit of stealing hens’ eggs, but he ‘even swallows the eggs of small birds, without breaking them,’ which again is a proof of the remarkable control these creatures possess of regulating the pressure of their powerful jaws.

Many of the African snakes climb trees, and also suspend themselves from a branch while reaching into a bird’s nest lower down for the eggs it may contain. Both Livingstone and Dr. Andrew Smith[10] make particular mention of some of the egg-eating snakes of South Africa, the latter in his general description of ophidians stating that ‘many, perhaps all snakes, devour eggs when they have an opportunity. A few feed entirely on eggs,’ notably some of the small tree snakes, to which the name Oligodon (few teeth) has been given, this family having no teeth on the palate, like all other snakes. Their food, therefore, cannot be of a nature to require a very strong grasp, though we have no authority for stating that the Oligodons feed exclusively on eggs.

There is, however, one of the family with a dentition so remarkable that it has been considered a distinct type, and Dr. Andrew Smith, who was the first to observe its habits, gave it the generic name of Anodon (toothless), the jaws being merely roughened with the rudiments of teeth. This little snake, of about two feet in length, is exclusively an egg-feeder. ‘Its business,’ says Professor Owen in his Odontography, ‘is to restrain the undue increase of small birds by devouring their eggs.’ Its remarkable organization is favourable for the passage of these thin-shelled eggs unbroken until far back in the throat or gullet, when the egg comes in contact with certain ‘gular teeth,’ which then break the shell without any loss of the contents to the feeder. These gular teeth are a curious modification of some of the spinal processes, presenting a singular anomaly in the presence of points of enamel on the extremity of some of them.

Professor Owen has very fully described this remarkable development,[11] and as his works have been the text-books of many later physiologists, his words may here be quoted, even at the risk of repetition.

‘In the rough tree snake, Deirodon scaber, with 256 vertebrÆ, a hypapophysis—from ?p? (Latin, sub), an offshoot from beneath—projects from the 32 anterior ones, which are directed backwards in the first ten, and incline forwards in the last ten, where they are unusually long, and tipped with a layer of hard cement (dentine). These perforate the dorsal parietes of the oesophagus, and serve as teeth.

‘Those who are acquainted with the habits and food of this species have shown how admirably this apparent defect—viz. the lack of teeth—is adapted to its well-being. Now, if the teeth had existed of the ordinary form and proportions in the maxillary and palatal regions, the egg must have been broken as soon as it was seized, and much of the nutritious contents would have escaped from the lipless mouth; but owing to the almost edentulous state of the jaws, the egg glides along the expanded mouth unbroken, and not until it has reached the gullet, and the closed mouth prevents the escape of any of the nutritious matter, is it exposed to the instruments adapted to its perforation. These instruments consist of the inferior spinous processes,’ etc., already described. ‘They may be readily seen even in very small subjects, in the interior of that tube in which their points are directed backwards. The shell being sawed open longitudinally by these vertebral teeth, the egg is crushed by the contractions of the gullet, and is carried to the stomach, where the shell is no doubt soon dissolved by the acid gastric juice.’

The two from Smith’s Zoology must be much magnified; the third, from the skeleton, being the true size, excepting that the ribs are broken short off, some entirely so. The minute processes extend two or more inches.

As the learned professor has described the Deirodon (neck-toothed) both under the head of teeth, and also of vertebrated animals, the two accounts are blended, but given verbatim as far as possible.

The colour of the Deirodon is of a brightish or yellowish brown, very minutely spotted with white. Such few true teeth as some individuals may possess are extremely small and conical, discovered only towards the angle of the mouth.

Dr. Andrew Smith first examined a specimen in 1829, when he found that the gular teeth commence exactly 2-1/4 inches behind the apex of the lower jaw, and penetrate the oesophagal canal through small holes in its tunics, and that each point is armed with enamel. He had observed that the living specimens which he had in captivity always, when feeding, retained the egg stationary about two inches from their head, and while there, used great efforts to crush it. Dissecting a specimen in order to investigate this strange action, he discovered the gular teeth just where the egg had stopped, and which, he felt satisfied, had assisted in fixing it there, and also in breaking the shell when subjected to the muscular action of the surrounding parts. The gular teeth are developed in very young Deirodons.

Dr. Smith saw that the broken shell was ejected, while the fluid contents were conveyed onwards; but this may have been an exceptional case, because by a snake in health egg-shells are easily digested. Probably those snakes watched by Dr. A. Smith being captives, and presumably not altogether as happy and healthy as in their sylvan homes, found the shells too much for them, and so ejected them; as the cobras above described disgorged the stolen eggs. This habit of disgorging food appears to be sometimes voluntary.

Snakes have been known to pass the egg through their body entire, but this also must be owing to an abnormal state of health or of habit, as the strong juices of the stomach, which can convert even bones and horn to nutriment, ordinarily dissolve an egg-shell.

Throughout nature we find that, whatever the habits of the creature may be, its structure and capacities are adapted to it. Every need is, as it were, anticipated in the process of development; and wherever, as in this harmless little tree snake, we find a departure from general rules, it is because some especial requirements are met, and in order that the creature may be the better prepared for the struggle for existence. In the present example we find a marvellous adaptation of spine bones to dental purposes; how many ages it has taken to develop them we cannot conjecture. All we know is that these spinal projections are just the sort of teeth that the egg-swallower requires, and that its natural teeth are gradually becoming obsolete from disuse.

A writer who was quoted at some length in the Zoologist for 1875, and in several other contemporary journals, stated that some snakes ‘suck out the contents of hen’s eggs by making a hole at the end.’[12]

We are not told with what instrument these evidently scientific serpents punctured the shell. Some skill is required, as schoolboys give us to understand, to prick an egg-shell without breaking it; and even when the hole is bored, additional care is required to suck out the contents. How a snake could first grasp firmly, and then puncture a fowl’s egg, is incomprehensible; how the sucking process is achieved is still more so. We can understand that a snake which discovered a broken egg might seem to lap some of the contents, because, as we shall by and by show, the tongue habitually investigates, and is immediately in requisition under all circumstances. But to lap up an egg would be a very slow process for so slender an instrument. One is reminded of the dinner which Sir Reynard invited his friend the Stork to partake with him.

While still marvelling over these South African egg-suckers, I watched some lizards with a broken egg in their cage. Their tongues were long, thin, blade-like, and bifid, much better adapted for the purpose of lapping than that of a snake, yet stupidly slow and inefficient was this ribbon-like tongue. The lizards threw it out, spatula-fashion, into the midst of the pool of egg which was spreading itself over the floor, and caught whatever of the fluid adhered to it. Had the lizards possessed lips adapted for such a purpose, and, in addition, intelligence enough to ‘suck,’ they might have drawn some of the cohesive mass into their throats, but they only obeyed their instinctive habit of lapping. Snakes would do the same. Their habit is to moisten the tongue in lapping; and I fear we must not place too much credence in the exceptional intelligence of that South African egg-sucker, but rather regret the loose account which conveys so erroneous an impression. I watched those lizards for many minutes, and decided that the egg would be dried up long before it could be consumed by lizard-lapping.

The tongue of a snake is undoubtedly an important and highly-developed organ. That its sensitiveness assists the smell, we have reason to believe, and possibly it possesses other faculties of which we are at present ignorant. In the case of an unbroken egg, for instance, the tongue has told the snake that there is something good inside it; and instinct immediately leads the reptile to get the awkward mouthful between its jaws, which expand just so far as to retain it safely, yet just so lightly that not one of those rows of long, sharp teeth shall penetrate the shell or fracture it in the slightest degree. How delicate must be the adjustment whereby those six jaws, all bristling with fine, needle-like teeth, grasp and yet not break the delicate shell! for, after all, an egg is a fragile substance in proportion to the size of the feeder and its muscular power.

Snakes have been known to get choked in attempting to swallow an egg, as they have also come to grief with other impediments, such as horns of cattle; but this we must attribute to their not being able to estimate their own swallowing capacities, or to some other untoward event.

The Messrs. Woodward’s scientific snake would not have crept into these pages had it not previously figured in the Zoologist, and thence copied in other prints, thereby misleading many readers. It also proved a subject worth discussing by thinking persons, and was alluded to very particularly by an ophiological friend and publisher in a letter to myself, which may be here usefully quoted. My friend, who has long stimulated me by his kind encouragement of my work, and by the assistance of his experience and judgment, was pleased to express much interest in a little paper on the Deirodon[13], which I had written for Aunt Judy’s Magazine, he having read it shortly before the appearance of the Messrs. Woodward’s statement in the Zoologist, April 1875:—

‘In this month’s Zoologist,’ wrote my friend, ‘a writer says that a certain snake makes havoc of the hen-house, by boring a hole in the egg and sucking its contents! Can this be true? To a letter of mine to Mr. Newman (the then editor of the Zoologist), on the subject, he replies, “With regard to snakes eating eggs, it has been repeated so often that I cannot help fearing Mr. Woodward may have imbibed the notion from American sources. It is so common in the United States to find snakes in holes in the bottoms of trees made by woodpeckers, that it seems almost impossible to resist the conviction that they enter these holes to get the birds themselves, or their young, or their eggs. It must be regretted that those witnesses who come into court with such evidence are not, generally speaking, the kind of close observers in whose dicta we can place implicit reliance.” This,’ continues my correspondent, ‘Mr. Newman writes after I had suggested that some families of snakes have triturating powers (learned from Aunt Judy) in the throat, independent altogether of palatal teeth. The subject seems to be as much steeped in the unknown, as are the ways of the beautiful creatures themselves.’

This from a well-known and highly-popular publisher, a man of education, culture, and scientific attainments, though snakes hitherto had not been his specialty, any more than that of the late editor of the Zoologist. The latter, however, admitting his doubts on the subject of ophidian egg-feeders, would have done well to have added a note to that effect to the account given by Mr. Woodward, which, simply from its appearance in a scientific journal, might be received as authority.

A few more well-known proofs of ophidian taste for eggs may conclude this chapter. Of our own green or ring snake (Coluber natrix), Mr. Bell says, ‘It feeds upon young birds, eggs, and mice, but prefers frogs.’ In Balfour’s India, on the subject of cobra-worship, mention is made of the snakes getting into larders for eggs and milk, and being protected as the good genius of the house on such occasions.

But the HindÛ custom of placing eggs for snakes at their serpent festivals must be too familiar to most of my readers to need further comment.