The way being thus prepared she hurries back with her wings quivering and her whole manner betokening joyful triumph at the completion of her task. We, in the meantime, have become as much excited over the matter as she is herself. She picks up the caterpillar, brings it to the mouth of the burrow and lays it down. Then, backing in herself, she catches it in her mandibles and drags it out of sight, leaving us full of admiration and delight.

How clear and accurate must be the observing powers of these wonderful little creatures! Every patch of ground must, for them, have its own character; a pebble here, a larger stone there, a trifling tuft of grass—these must be their landmarks. And the wonder of it is that their interest in each nest is so temporary. A burrow is dug, provisioned and closed up, all in two or three days, and then another is made in a new place with everything to learn over again.

From this time (July thirteenth) on to the first of September our garden was full of these wasps, and they never lost their fascination for us, although owing to a decided difference between their taste and ours as to what constituted pleasant weather all our knowledge of them was gained by the sweat of our brows. When we wished to utilize the cool hours of the morning or of the late afternoon in studying them, or thought to take advantage of a cloud which cast a grateful shade over the sun at noonday, where were our Ammophiles? Out of sight entirely, or at best only to be seen idling about on the flowers of the onion or sorrel. At such a time they seemed to have no mission in life and no idea of duty. But when the air was clear and bright and the mercury rose higher and higher, all was changed. Their favorite working hours were from eleven in the morning to three in the afternoon, and when they did work they threw their whole souls into it. It was well that it was so, for they certainly needed all the enthusiasm and perseverance that they could muster for such wearisome and disappointing labor. Hour after hour was passed in search, and often there was nothing to show at the end of it, for, since the caterpillars that they wanted were nocturnal species, most of them were under ground in the day-time. The species observed by Fabre knew, by some subtle instinct, where to find the worm, and unearthed it from its burrow. Urnaria, on the contrary, never dug for her prey, but hunted on bare ground, on the purslane, and most of all on the bean-plants. These were examined carefully, the wasp going up and down the stems and looking under every leaf, but the search was so frequently unsuccessful that in estimating their work we are inclined to think that they can scarcely average one caterpillar a day. When they were hunting over bare ground they often paused and seemed to listen, and in the beginning we expected to see them burrow down and drag a victim from under the soil, but this never happened.

In this species, as in every one that we have studied, we have a most interesting variation among the different individuals, not only in methods but in character and intellect. While one was beguiled from her hunting by every sorrel blossom she passed, another stuck to her work with indefatigable perseverance. While one stung her caterpillar so carelessly and made her nest in so shiftless a way that her young could only survive through some lucky chance, another devoted herself to these duties, not only with conscientious thoroughness, but with an apparent craving after artistic perfection that was touching to see.

The method employed by the Ammophilae in stinging their prey is more complex than that of any other predatory wasp. The larvae with which they provision their nests are made up of thirteen segments, and each of these has its own nervous centre or ganglion. Hence if the caterpillar is to be reduced to a state of immobility, or to state so nearly approaching immobility that the egg may be safely laid upon it, a single sting, such as is given by some of the Pompilidae to their captured spiders, will be scarcely sufficient. All this we knew from Fabre's "Souvenirs," and yet we were not at all prepared to believe that any plain American wasp could supply us with such a thrilling performance as that of the Gallic hirsuta, which he so dramatically describes. We were, however, most anxious to be present at the all-important moment that we might see for ourselves just how and where Ammophila urnaria stings her victim.

For a whole week of scorching summer weather we lived in the bean patch, scorning fatigue. We quoted to each other the example of Fabre's daughter Claire, whose determination to solve the problem of Odynerus led to a sun-stroke. We followed scores of wasps as they hunted; we ran, we threw ourselves upon the ground, we scrambled along on our hands and knees in our desperate endeavors to keep them in view, and yet they escaped us. After we had kept one in sight for an hour or more some sudden flight would carry her far away and all our labor was lost.

At last, however, our day came. We were doing a little hunting on our own account, hoping to find some larvae which we could drop in view of the wasps and thus lead them to display their powers, when we saw an urnaria fly up from the ground to the underside of a bean leaf and knock down a small green caterpillar. Breathless with an excitement which will be understood by those who have tasted the joy of such a moment, we hung over the actors in our little drama. The ground was bare, we were close by and could see every motion distinctly. Nothing more perfect could have been desired.

The wasp attacked at once but was rudely repulsed, the caterpillar rolling and unrolling itself rapidly and with the most violent contortions of the whole body. Again and again its adversary descended but failed to gain a hold. The caterpillar in its struggles, flung itself here and there over the ground, and had there been any grass or other covering near by it might have reached a place of partial safety, but there was no shelter within reach, and at the fifth attack the wasp succeeded in alighting over it, near the anterior end, and in grasping its body firmly in her mandibles. Standing high on her long legs and disregarding the continued struggles of her victim, she lifted it from the ground, curved her abdomen under its body, and darted her sting between the third and fourth segments. From this instant there was a complete cessation of movement on the part of the unfortunate caterpillar. Limp and helpless, it could offer no further opposition to the will of its conqueror. For some moments the wasp remained motionless, and then, withdrawing her sting, she plunged it successively between the third and the second, and between the second and the first segments.



The caterpillar was now left lying on the ground. For a moment the wasp circled above it and then, descending, seized it again, further back this time, and with great deliberation and nicety of action gave it four more stings, beginning between the ninth and tenth segments and progressing backward.

Urnaria, probably feeling—as we certainly did—reaction from the strain of the last few minutes, and a relief at the completion of her task, now rested from her labors. Standing on the ground close by she proceeded to smooth her body with her long hind legs, standing in the meantime, almost on her head, with her abdomen directed upward. She then gave her face a thorough washing and rubbing with her first legs, and not until she had made a complete and satisfactory toilet did she return to the caterpillar.

We saw Ammophila capture her prey only three times during the whole summer, but from these observations and from the condition of her caterpillars taken at various times from nests, her method seems to be wonderfully close to that of hirsuta, with just about the same amount of variation in different individuals.

Thus in our second example, she stung the first three segments in the regular order, the third, the second, and lastly (and most persistently) the first. She then went on, without a pause, to sting the fourth, fifth, sixth, and seventh, stopping at this point and leaving the posterior segments untouched. In our first example, it will be remembered, the middle segments were spared. The sting being completed, she proceeded to the process known as malaxation, which consists in repeatedly squeezing the neck of the caterpillar, or other victim, between the mandibles, the subject of the treatment being turned around and around so that all sides may be equally affected.

In our third case a caterpillar which we had caught was placed in front of a wasp just after she had carried the second larva into her nest. She seemed rather indifferent to it, passing it once or twice as she ran about, but finally picked it up and gave it one prolonged sting between the third and fourth segments. She then spent a long time in squeezing the neck, pinching it again and again. It was then left on the ground, and as she showed no further interest in it we carried it home for further study.

In the three captures, then, that came under our observation, all the caterpillars being of the same species and almost exactly of the same size, three different methods were employed. In the first, seven stings were given at the extremities, the middle segments being left untouched, and no malaxation was practised. In the second, seven stings again but given in the anterior and middle segments, followed by slight malaxation. In the third, only one sting was given but the malaxation was prolonged and severe.



LEAF-CUTTING ANTS

(FROM THE NATURALIST IN NICARAGUA.)

BY THOMAS G. BELT, F.G.S.



Nearly all travellers in tropical America have described the ravages of the leaf-cutting ants (OEcodoma); their crowded, well-worn paths through the forests, their ceaseless pertinacity in the spoliation of the trees—more particularly of introduced species—which are left bare and ragged, with the mid-ribs and a few jagged points of the leaves only left. Many a young plantation of orange, mango, and lemon trees has been destroyed by them. Again and again have I been told in Nicaragua, when inquiring why no fruit-trees were grown at particular places, "It is no use planting them; the ants eat them up." The first acquaintance a stranger generally makes with them is on encountering their paths on the outskirts of the forest crowded with the ants; one lot carrying off the pieces of leaves, each piece about the size of a sixpence, and held up vertically between the jaws of the ant; another lot hurrying along in an opposite direction empty handed, but eager to get loaded with their leafy burdens. If he follows this last division, it will lead him to some young trees or shrubs, up which the ants mount; and where each one, stationing itself on the edge of a leaf, commences to make a circular cut, with its scissor-like jaws, from the edge, its hinder-feet being the centre on which it turns. When the piece is nearly cut off, it is still stationed upon it, and it looks as though it would fall to the ground with it; but, on being finally detached, the ant is generally found to have hold of the leaf with one foot, and soon righting itself, and arranging its burden to its satisfaction, it sets off at once on its return. Following it again, it is seen to join a throng of others, each laden like itself, and, without a moment's delay, it hurries along the well-worn path. As it proceeds, other paths, each thronged with busy workers, come in from the sides, until the main road often gets to be seven or eight inches broad, and more thronged than the streets of the city of London.



After travelling for some hundreds of yards, often for more than half a mile, the formicarium is reached. It consists of low, wide mounds of brown, clayey-looking earth, above and immediately around which the bushes have been killed by their buds and leaves having been persistently bitten off as they attempted to grow after their first defoliation. Under high trees in the thick forest the ants do not make their nests, because, I believe, the ventilation of their underground galleries, about which they are very particular, would be interfered with, and perhaps to avoid the drip from the trees. It is on the outskirts of the forest, or around clearings, or near wide roads that let in the sun, that these formicariums are generally found. Numerous round tunnels, varying from half an inch to seven or eight inches in diameter, lead down through the mounds of earth; and many more, from some distance around, also lead underneath them. At some of the holes on the mounds ants will be seen busily at work, bringing up little pellets of earth from below, and casting them down on the ever-increasing mounds, so that its surface is nearly always fresh and new-looking.

Standing near the mounds, one sees from every point of the compass ant-paths leading to them, all thronged with the busy workers carrying their leafy burdens. As far as the eye can distinguish their tiny forms, troops upon troops of leaves are moving up towards the central point, and disappearing down the numerous tunnelled passages. The outgoing, empty-handed hosts are partly concealed amongst the bulky burdens of the incomers, and can only be distinguished by looking closely amongst them. The ceaseless, toiling hosts impress one with their power, and one asks—What forests can stand before such invaders? How is it that vegetation is not eaten off the face of the earth? Surely nowhere but in the tropics, where the recuperative powers of nature are immense and ever active, could such devastation be withstood.

Further acquaintance with the subject will teach the inquirer that, just as many insects are preserved by being distasteful to insectivorous birds, so very many of the forest trees are protected from the ravages of the ants by their leaves either being distasteful to them, or unfitted for the purpose for which they are required, whilst some have special means of defence against their attacks.

These ants do not confine themselves to leaves, but also carry off any vegetable substance that they find suitable for growing the fungus on. They are very partial to the inside white rind of oranges, and I have also seen them cutting up and carrying off the flowers of certain shrubs, the leaves of which they neglected. They are very particular about the ventilation of their underground chambers, and have numerous holes leading up to the surface from them. These they open out or close up, apparently to keep up a regular degree of temperature below. The great care they take that the pieces of leaves they carry into the nest should be neither too dry nor too damp, is also consistent with the idea that the object is the growth of a fungus that requires particular conditions of temperature and moisture to ensure its vigorous growth. If a sudden shower should come on, the ants do not carry the wet pieces into the burrows, but throw them down near the entrances. Should the weather clear up again, these pieces are picked up when nearly dried, and taken inside; should the rain, however, continue, they get sodden down into the ground, and are left there. On the contrary, in dry and hot weather, when the leaves would get dried up before they could be conveyed to the nest, the ants, when in exposed situations, do not go out at all during the hot hours, but bring in their leafy burdens in the cool of the day and during the night. As soon as the pieces of leaves are carried in they must be cut up by the small class of workers into little pieces. I have never seen the smallest class of ants carrying in leaves! their duties appear to be inside, cutting them up into smaller fragments, and nursing the immature ants. I have, however, seen them running out along the paths with the others; but instead of helping to carry in the burdens, they climb on the top of the pieces which are being carried along by the middle-sized workers, and so get a ride home again. It is very probable that they take a run out merely for air and exercise. The largest class of what are called workers are, I believe, the directors and protectors of the others. They are never seen out of the nest, excepting on particular occasions, such as the migrations of the ants, and when one of the working columns or nests is attacked, they then come stalking up, and attack the enemy with their strong jaws. Sometimes, when digging into the burrows, one of these giants has unperceived climbed up my dress, and the first intimation of his presence has been the burying of his jaws in my neck, from which he would not fail to draw blood. The stately observant way in which they stalk about, and their great size, compared with the others, always impressed me with the idea that in their bulky heads lay the brains that directed the community in their various duties. Many of their actions, such as that I have mentioned of two relays of workmen carrying out the ant food, can scarcely be blind instinct. Some of the ants make mistakes, and carry in unsuitable leaves. Thus grass is always rejected by them, but I have seen some ants, perhaps young ones, carrying leaves of grass; but after a while these pieces are always brought out again and thrown away. I can imagine a young ant getting a severe ear-wigging from one of the major-domos for its stupidity.



I shall conclude this long account of the leaf-cutting ants with one more instance of their reasoning powers.

A nest was made near one of our tramways, and to get to the trees the ants had to cross the rails, over which the wagons were continually passing and repassing. Every time they came along a number of ants were crushed to death. They persevered in crossing for some time, but at last set to work and tunnelled underneath each rail. One day, when the wagons were not running, I stopped up the tunnels with stones; but although great numbers carrying leaves were thus cut off from the nest, they would not cross the rails, but set to work making fresh tunnels underneath them. Apparently an order had gone forth, or a general understanding been come to, that the rails were not to be crossed.



SOME WONDERFUL SPIDERS

(FROM A JOURNAL OF RESEARCHES, ETC.)

BY CHARLES DARWIN.



The number of spiders, in proportion to other insects, is here compared with England very much larger; perhaps more so than with any other division of the articulate animals. The variety of species among the jumping spiders appears almost infinite. The genus, or rather family of Epeira, is here characterized by many singular forms; some species have pointed coriaceous shells, others enlarged and spiny tibiae. Every path in the forest is barricaded with the strong yellow web of a species belonging to the same division with the Epeira clavipes of Fabricius, which was formerly said by Sloane to make, in the West Indies, webs so strong as to catch birds. A small and pretty kind of spider, with very long forelegs, and which appears to belong to an undescribed genus, lives as a parasite on almost every one of these webs. I suppose it is too insignificant to be noticed by the great Epeira, and is therefore allowed to prey on the minute insects, which, adhering to the lines, would, otherwise be wasted. When frightened, this little spider either feigns death by extending its front legs, or suddenly drops from the web. A large Epeira of the same division with Epeira tuberculata and conica is extremely common, especially in dry situations. Its web, which is generally placed among the great leaves of the common agave, is sometimes strengthened near the centre by a pair or even four zigzag ribbons, which connect two adjoining rays. When any large insect, as a grasshopper or wasp, is caught, the spider by a dexterous movement, makes it revolve very rapidly, and at the same time emitting a band of threads from its spinners, soon envelops its prey in a case like the cocoon of a silk worm. The spider now examines the powerless victim, and gives the fatal bite on the hinder part of its thorax; then retreating, patiently waits till the poison has taken effect. The virulence of this poison may be judged from the fact that in half a minute I opened the mesh, and found a large wasp quite lifeless. This Epeira always stands with its head downwards near the centre of the web. When disturbed, it acts differently according to circumstances: if there is a thicket below, it suddenly falls down; and I have distinctly seen the thread from the spinners lengthened by the animal while yet stationary, as preparatory to its fall. If the ground is clear beneath, the Epeira seldom falls, but moves quickly through a central passage from one side to the other. When still further disturbed, it practises a most curious manoeuvre: Standing in the middle, it violently jerks the web, which is attached to elastic twigs, till at last the whole acquires such a rapid vibratory movement, that even the outline of the spider's body becomes indistinct.



It is well known that most of the British spiders, when a large insect is caught in their webs, endeavor to cut the lines and liberate their prey, to save their nests from being entirely spoiled. I once, however, saw in a hot-house in Shropshire a large female wasp caught in the irregular web of a quite small spider; and this spider, instead of cutting the web, most perseveringly continued to entangle the body, and especially the wings, of its prey. The wasp at first aimed in vain repeated thrusts with its sting at its little antagonist. Pitying the wasp, after allowing it to struggle for more than an hour, I killed it and put it back into the web. The spider soon returned; and an hour afterwards I was much surprised to find it with its jaws buried in the orifice, through which the sting is protruded by the living wasp. I drove the spider away two or three times, but for the next twenty-four hours I always found it again sucking at the same place. The spider became much distended by the juices of its prey, which was many times larger than itself.

I may here just mention, that I found near St. Fe Bajada, many large black spiders, with ruby-colored marks on their backs, having gregarious habits. The webs were placed vertically, as is invariably the case with the genus Epeira; they were separated from each other by a space of about two feet, but were all attached to certain common lines, which were of great length, and extended to all parts of the community. In this manner the tops of some large bushes were encompassed by the united nets. Azara has described a gregarious spider in Paraguay, which Walckenaer thinks must be a Theridion, but probably it is an Epeira, and perhaps even the same species with mine. I cannot, however, recollect seeing a central nest as large as a hat, in which, during autumn, when the spiders die, Azara says the eggs are deposited. As all the spiders which I saw were of the same size, they must have been nearly of the same age. This gregarious habit, in so typical a genus as Epeira, among insects, which are so bloodthirsty and solitary that even the two sexes attack each other, is a very singular fact.



WHAT I SAW IN AN ANT'S NEST

(FROM FACTS AND FICTIONS OF ZOOeLOGY.)

BY ANDREW WILSON.



Amongst those spectacles and incidents in human existence which remain fixed on the memory of the spectator from their sad or unwonted nature, that of a panic-stricken crowd, gathered by the report of some national disaster, stands pre-eminent. Still more terrible in its details is the history of some catastrophe which has laid a city in ruins and wrought death and desolation to thousands of the inhabitants. A deadly epidemic, or fatal plague, searing a nation with its dread, mysterious power, is a calamity appalling enough; but the spectacle of a city overthrown at one fell swoop by the earthquake shock may perhaps rank foremost amongst the untoward incidents which environ the sphere of man. A certain event, occurring during a recent holiday by the sea, tended forcibly to impress upon the mind that the great catastrophes of life are not limited to humanity's special sphere, and that in lower life panic and alarm seem to exercise no small influence, as in man's estate; whilst the incident referred to also afforded food for reflection on topics not far removed from some weighty matters in the history of man's own nature and constitution. In this latter view, it is especially hoped the observations of a brief period of leisure-time may not be without their due meed of interest.

The chance removal from its secure site, of a large stone placed in close proximity to the sea-beach, where the bliss of idleness was being fully exemplified by a small party of holiday-makers, proved, on close examination, to be the cause of a literal revolution in lower life. Imagine a city to be totally unroofed, try to conceive of the sudden downfall of houses and buildings, and the consequent panic of the inhabitants, and you may obtain an idea of the disturbance on simple procedure effected in the peaceable, well-ordered colony of ants which had located themselves securely beneath the friendly shelter of the stone. The scene presented to view was one of the most curious and interesting which could engage the attention of an observer in any field of inquiry, and the occurrence certainly banished the idle mood of the time, and lent a zest to the subsequent hours of our holiday. Running hither and thither in wild confusion were the denizens of this underground colony; their six little legs carrying their curious globular bodies backward and forward over the disturbed area from which the stone had been removed. At first the movements of the ants were extremely erratic and purposeless. Panic and alarm appeared to be the order of the day during the few minutes which elapsed after removal of the stone. But soon the eye could discern movements of purposive kind on the part of the alarmed residents. There was "racing and chasing" in all directions: but the ants which had at first radiated from the centre of disturbance, as if on some definite quest, soon returned thereunto, and continued to advance and retire from the field of action with tolerable regularity. Not less than sixty or seventy ants appeared to be engaged in this labor of scouring the country around. The object of their repeated journeys in all directions was soon discovered. They were the self-appointed scouts, engaged in the work of reconnoitring. Such at least is a fair interpretation of the acts of the ants, and such also is the conclusion borne out by the subsequent course of events. For, after the scouts had spent a considerable time in their rapid journeys to the environments of the nest, a new set of ants appeared upon the scene, destined to perform a highly important series of labors.

The scouts continued their journeyings, and gave one the idea of a set of fussy individuals who were superintending, or even bullying, their new neighbors, who appeared from amongst the ruins and debris of the ant city, carrying in their mouths certain oval bodies of a dirty-white color, and measuring each about one-third of an inch in length. Each of these bodies closely resembled a grain of corn in shape, size, and appearance. The spectacle of these small insects carrying off these bodies in their powerful jaws impressed one forcibly with the idea that, relatively to its size, an ant is an herculean insect.

Occasionally there might be seen certain rather ludicrous incidents connected with the removal of the objects in question. One ant might be witnessed in the endeavor to hoist the oval body it was carrying in its mouth over some obstacle lying in the path, and the staggering gait of the insect seemed very accurately to mimic the similar disposition of a human porter struggling under a burdensome load. Another ant, carrying the oval body before it, would arrive at a steep incline formed of loose sand, and presenting a treacherous surface even to the light feet of the insect. The efforts of the ant to carry the body upward being found to be fruitless, the insect might be seen to whirl about with great rapidity of action, and ascend the hill backward, pulling the body after it, instead of pushing it as before.

Another instance might be witnessed in which an ant which had literally come to grief with its burden would be assisted by a kindly neighbor; but it was no uncommon sight to behold in the excessive eagerness of the insects an actual means of defeating the object they had in view, since two ants would in some cases seize the same burden, and then came the tug of war. One pulled one way whilst the other tugged in the opposite direction; and the observer could almost have supposed that the burden itself might have been parted in twain by the treatment to which it was subjected—the incident affording a new application of the remark that a surfeit of zeal is destructive of the best intentions. The nature of the bodies which the ants seemed so excessively anxious to preserve from injury was readily determined. The oval bodies, resembling grains of corn, were the pupae or chrysalides of the ants—the sleeping babies and young hopefuls, on whom the hopes of the colony were, and I may say, are, founded. It is noteworthy, however, that upon some mistaken notions regarding the nature of these bodies many of the ideas concerning the frugal care of these insects were founded. Solomon's advice that the sluggard should "go to the ant," with the view of considering her ways and gaining wisdom as a result of the study, was in days of old thought to be approved by the observation that the ants husbanded their stores of food in the shape of the grains of corn they had gained from the autumnal store. There can be little doubt that some species of ants do store food; but their praiseworthy actions in this direction have been greatly exaggerated, and there appears, indeed, to be some danger of idle persons being prepared with the retort to the wise man, that the ant is by no means the model creature he thought her to be. If, however, the supposed corn-grains turn out to be the rising generation of ants in their chrysalis-state, it may be said that what the ants may have lost in the way of fame in this direction has been amply compensated for by the discovery of more wonderful traits of character than Solomon could possibly have dreamt of.

The work of removing the developing population thus appeared in our ant's nest to absorb the entire energies of the alarmed denizens. Pupa after pupa was carried out from amongst the debris and taken for a considerable distance—certainly fifteen inches—to a place of security, beneath a small sloping stone of flat shape, which roofed over a hollow in the ground. So far as I could observe, the scouts must have discovered this place of refuge, and have communicated the intelligence to their neighbors. The regularity with which the slumbering innocents were conveyed to the same spot would appear to point to concerted work and to a definite idea, if one may so term it, having animated the laborers. I was careful to ascertain at an early stage of the proceedings that the place of refuge had no communications with the nest. It was, in point of fact, an entirely new habitation, and, as far as human judgment might venture upon an opinion, the new residence appeared to give promise of being a safe and convenient domicile. Now and then an ant would emerge from the ruins of the nest carrying a younger hopeful in the larva or caterpillar stage. This latter was a little white grub, which corresponds in its development to the grub or caterpillar of the butterfly or fly; the ants thus exemplifying insects which undergo a complete "metamorphosis." It was rather a difficult matter to ascertain clearly if the ants were actually excavating the chrysalides from amongst the debris. Bearing in mind what Sir John Lubbock has told us concerning the apparent inability of ants to discover the whereabouts of companions buried under earth, I rather lean to the belief that my ants simply conveyed to a place of safety those chrysalides which were at hand and readily obtainable. The latter fact I could not ascertain, since I feared to disturb the ants at their interesting labors; but a simple experiment served to show the feasibility of the idea that the chrysalides were probably within easy reach of the ants.

Taking possession of one chrysalis which was being conveyed to the new domicile, I buried it about half an inch deep in the sand, directly in the track over which the ants were journeying to their new residence, and a second chrysalis I placed at a little distance from this track, but in a spot over which numerous ants were running apparently without any definite aim. The second pupa ant was not buried in any sense, and was covered merely with a sprinkling of sand. The result in both cases was negative. No attempt was made to disinter the chrysalis from the beaten track, although numberless ants walked directly over it; and I extricated the chrysalis five hours after its interment, and when the busy scene of the morning had been replaced by a dull prospect, over which only a single ant now and then hurried in a rapid fashion. The other chrysalis was also unnoticed, despite its proximity to the surface of the sand. Whether or not ants want a sense of smell or other means of guiding them to the whereabouts of their neighbors or children, is a subject difficult of determination either toward a positive or negative result. And I am the more inclined to wonder at the incapacity of the insects to discover their buried companions, since they appear to be perfectly capable of detecting them at a considerable distance above ground. When a chrysalis was placed in a spot remote from the nest, and an ant placed within a foot or so of the chrysalis, the insect would occasionally seem to be attracted to the neighborhood of the object. I frequently observed that if an ant happened to crawl within two or three inches of the chrysalis as it lay on the ground, it appeared to become conscious of the object, although at the same time it seemed ignorant of its precise locality. In such a case the insect would proceed hither and thither in an erratic fashion, but would continue to hover or rotate around the chrysalis until it seized the object and bore it off in triumph in its jaws. Relatively to the size of the ant, we must consider this latter incident by no means a slight tribute to its acuteness.

The busy scene resulting from the disturbance of the nest proceeded actively during at least two hours. The nest appeared to be by no means a large one. At the end of two hours, however, the ants were still rushing hither and thither, bent on errands unknown to their observers, although the work of conveying the chrysalides had at the lapse of the period just mentioned entirely ceased. Five and a half hours after the nest had been alarmed, not an ant was visible over the disturbed area, and our next task was that of investigating the manner in which the insects had dispersed themselves and their belongings in their new habitation by carefully removing the flat sloping stone already mentioned as that beneath which the main stream of the ants had disappeared. Not an insect was to be seen after this operation was performed, and it was only after the removal of several small stones which lay below the flat stone that the colony in its new sphere was brought into view. Our investigation once again excited the restless beings. Then ensued, for the second time, the seizure of the chrysalides, which, however, were to be seen packed together in a secure position and already partly covered with particles of earth and sand. To have reached the position in which we found them, the insects must have descended at least three inches after entering below the stone, and the labor of the continual ascent in search of fresh chrysalides must therefore have been of no light kind. We saw enough to convince us that the ants had already settled down in a new organization, which, with an undisturbed history, might repeat the peaceful state of their former life; and we also had the thought presented, that in the exercise of their duties under the pressure of an unwonted exigency, the insect behaved and acted with no small degree of intelligence, and apparently in harmonious concert to the desired end.

But the thoughts suggested by the brief observation of the disturbed ant's nest hardly end thus. We may very naturally proceed to inquire into the regular organization and constitution of the ant colony, and also, as far as fact and theory may together lead, into the analogies—if analogies there be—which exist between the social instincts of ants and the ways of the higher animals, man included.



The common ants and their neighbors belong to the order of insects known as the Hymenoptera, a group represented by other insects of "social" habits, such as bees, wasps, and hornets. The termites, or white ants of the tropics, are the only "ants" foreign to this order of insects, the white ants being near relations of the dragonflies, may-flies, etc. The family history of the latter, as told by Mr. Bates, may serve to introduce us agreeably to ant society at large. The nests of the termites may attain a height of five feet, and present the appearance of conical hillocks, formed of earth particles "worked," says Mr. Bates, "with a material as hard as stone." In the neighborhood of the nests, narrow covered galleries or underground ways are everywhere to be seen, these latter being the passages along which the materials used for building the nests are conveyed. The termites are small soft-bodied animals of a pale color, but resemble the common or true ants in that they live in colonies, composed, like those of bees, of three chief grades of individuals. These grades are known as males, females, and blind "neuters," the latter forming at once the largest bulk of the population, and including in their numbers the true "working classes" of this curious community. In the common ants, the "neuters" are regarded as being Undeveloped female insects. These neuters exhibit in the termites a further division into ordinary "workers" (Figs. 1, 4), which perform the multifarious duties connected with the ordinary life of the colony, and "soldiers" (3), which perfectly exemplify the laws of military organization in higher life, in that they have no part in the common labor, but devote themselves entirely to the defence of the colony and to the

"Pride, pomp, and circumstance of glorious war."

The workers appear to perform a never-ending round of duties. They build the nests, make the roads, attend to the wants of the young, train up the latter in the ways of ant existence, wait on the sovereigns of the nest, and like diplomatic courtiers, duly arrange for the royal marriages of the future. As Mr. Bates remarks, "The wonderful part in the history of the termites is, that not only is there a rigid division of labor, but nature has given to each class a structure of body adapting it to the kind of labor it has to perform. The males and females form a class apart; they do no kind of work, but in the course of growth acquire wings to enable them to issue forth and disseminate their kind. The workers and soldiers are wingless, and differ solely in the shape and armature of the head. This member in the laborers is smooth and rounded, the mouth being adapted for the working of the materials in building the hive. In the soldier the head is of very large size, and is provided in almost every kind with special organs of offence and defence in the form of horny processes resembling pikes, tridents, and so forth.... The course of human events in our day seems, unhappily, to make it more than ever necessary for the citizens of civilized and industrious communities to set apart a numerous armed class for the protection of the rest; in this, nations only do what nature has of old done for the termites. The soldier termite, however, has not only the fighting instinct and function; he is constructed as a soldier, and carries his weapons not in his hand but growing out of his body." When a colony of termites is disturbed, the ordinary citizens disappear and the military are called out. "The soldiers mounted the breach," says Mr. Bates, "to cover the retreat of the workers," when a hole was made in the archway of one of their covered roads, and with military precision the rearmen fall into the vacant places in the front ranks as the latter are emptied by the misfortune of war.



In a termite colony there is but one king and queen, the royal couple being the true parents of the colony. The state-apartments are situated in the centre of the hive, and are strictly guarded by workers. Both king and queen are wingless, and are of larger size than their subjects. The queen engages in a continual round of maternal duties, the eggs deposited by the sovereign-mother being at once seized by the workers and conveyed to special or "nursery cells," where the young are duly tended and brought up. Once a year, at the beginning of the rainy season, winged termites appear in the hive as developments of certain of the eggs laid by the queen-termite. These latter are winged males and females (Fig. 1, 1), the two sexes being present in equal numbers. Some of these, after shedding their wings, become the founders—kings and queens—of new communities, the privilege of sex being thus associated with the important and self-denying work of perpetuating the species or race in time. Sooner or later—a termite family takes about a year to grow—a veritable exodus of the young winged termites takes place; and just before this emigration movement occurs, a hive may be seen to be stocked with "termites" of all castes and in all stages of development. The workers never exhibit a change of form during their growth; the soldiers begin to differ from the workers in the possession of larger heads and jaws; whilst the young which are destined to become the winged males and females are distinguished by the early possession of the germs of wings which become larger as the skin is successively moulted. Amongst the bees, blind Huber supposed that an ordinary or neuter egg develops into a queen bee if the larva is fed upon a special kind of food—"royal food," as it is called. Although some entomological authorities differ from Huber with regard to the exact means by which the queen bee is reared and specialized from other larvae, yet the opinion thus expressed possesses a large amount of probability. Whatever may be the exact method or causes through or by which the queen bee is developed, Mr. Bates strongly asserts that the differences between the soldiers and worker termites are distinctly marked from the egg. This latter observer maintains that the difference is not due to variations in food or treatment during their early existence, but is fixed and apparent from the beginning of development. This fact is worthy of note, for it argues in favor of the view that if, as is most likely, the differences between the grades of termites may have originally been produced by natural selection or other causes, these differences have now become part and parcel of the constitution of these insects, and are propagated by the ordinary law of heredity. Thus acquired conditions have become in time the natural "way of life" of these animals.

Mr. Bates has also placed on record the noteworthy fact that a species of termites exists in which the members of the soldier class did not differ at all from the workers "except in the fighting instinct." This observation, if it may be used at all in elucidation of the origin of the curious family life of these insects, points not to sudden creation, but to gradual acquirement and modification as having been the method of development of the specialized classes and castes in termite society. Firstly, we may thus regard the beginnings of the further development of a colony to appear in a nest in which workers and soldiers are alike, as stated by Mr. Bates. Then, through the practice of the fighting instinct, we may conceive that natural selection would be competent to adapt the soldiers more perfectly for their duties militant, by developing the head and jaws as offensive weapons. Possibly, were our knowledge of the termites at all complete, we should meet with all stages in the development and specialization of the various grades of society amongst these insects—at least the present state of our knowledge would seem to lead to such a conclusion as being much more feasible than the theory of special or sudden creation of the peculiarities of the race. It is admitted that the termites are in many respects inferior in structure to the bees and wasps, whilst the white ants themselves are the superiors of their own order—that of the Neuroptera. That the termites preceded the bees and their neighbors, the common ants, in the order of development of social instincts, is a conclusion supported by the fact that the Neuroptera form the first group of insects which are preserved to us in the "records of the rocks." Fossil Neuroptera occur in the Devonian rocks of North America; the first traces of insects allied to the bees and wasps being geologically more recent, and appearing in the oolitic strata. The occurrence of high social instincts in an ancient group of insects renders the repetition of these instincts in a later and higher group the less remarkable. The observation, however, does not of necessity carry with it any actual or implied connection between the termites and their higher neighbors, although, indeed, the likeness between the social life of the two orders of insects might warrant such a supposition.



The common ants (Fig. 3), the study of which in their native haunts is a matter of no great difficulty, and one which will fully reward the seeking mind, like the termites, possess three grades of individuals. In a single ant's nest more than One female may be found, the ants differing from the bees in this respect; and in the nests of some species of ants there are apparently "soldiers" resembling the military termites in the possession of large heads and well-developed jaws. Very amazing differences are to be perceived amongst the various species of ants. Differences in size are of common occurrence, but naturalists have actually succeeded in classifying ants in a general way, by differences in manner and disposition. We know, for example, that the horse-ant (Formica rufa, Fig. 3) has little individual intelligence, but is extremely socialistic, and moves and acts en masse with precision and tact. Another species (F. fusca) is timid and retiring. F. pratensis is a revengeful creature, since it "worries" its fallen foes; F. cinerea is bold and audacious; others are termed "thieves" and "cowards"; some are phlegmatic; and to complete the list of failings and traits which are human enough in character, one species is said to present an invariable greediness as its prevailing characteristic. The common ants resemble the termites in the general details of their life. We see in an ant's nest the same restless activity of the workers, the same earnest attention paid to the young and pupae, the same instinct in shielding the young from danger, and much the same general routine of development. Certain rather special, and it may be said extraordinary, habits of ants may, however, demand notice before we attempt a brief survey of their instincts at large. Few readers are unacquainted with the Aphides, or plant-lice, those little wingless insects which infest our plants and herbs in myriads in summer. It is a fact now well known to naturalists, and first placed on record by Huber, that between the ants and plant-lice, relations of a very friendly and, as far as the ants are concerned, advantageous character have become established. Ants have been observed to stroke the tips of the bodies of the plant-lice with their antennae, this act causing the plant-lice to exude drops of a clear, sweet fluid, of which the ants are extremely enamoured. The ants would thus appear to habitually "milk" their insect-neighbors, and, as far as observation goes, some ants seem not merely to keep the plant-lice in their nests so as to form a veritable dairy establishment, but also to make provision in the future by securing the eggs of the aphides, and bringing up the young as we rear calves.



That the relation between the ants and plant-lice are of very stable kind is proved by the interesting remarks of Mr. Darwin, who "removed all the ants from a group of about a dozen aphides on a dock-plant, and prevented their attendance during several hours." Careful watching showed that the plant-lice after this interval did not excrete the sweet fluid. Mr. Darwin then stroked the plant-lice with a hair, endeavoring thus to imitate the action of the ant's feelers, but not a single plant-louse seemed disposed to emit the secretion. Thereafter a single ant was admitted to their company, the insect, in Mr. Darwin's words, appearing, "by its eager way of running about, to be well aware what a rich flock it had discovered." The ant first stroked one aphis and then another, each insect excreting a drop of the sweet juice "as soon as it felt the antennae;" and "even the quite young aphides behaved in this manner, showing that the action was instinctive, and not the result of experience." If, as Mr. Darwin remarks, it is a convenience for the aphides to have the sweet secretion removed, and that "they do not excrete solely for the food of the ants," the observation does not in any degree lessen the curious nature of the relationship which has become established between the ants and their neighbors, or the interesting features in ant life which have inaugurated and perpetuated the habit.

Not less remarkable are the "slave-making" instincts of certain species of ants. It may be safely maintained that the slave-making habit forms a subject of more than ordinary interest not merely to naturalists but to metaphysicians given to speculate on the origin and acquirement of the practices of human existence. Pierre Huber, son of the famous entomologist, was the first to describe the slave-making instincts in a species (Polyergus rufescens) noted for its predaceous instincts, and subsequent observations have shown that other species participate in these habits. Polyergus is thoroughly dependent on slaves. Without these bonds-men it is difficult to see how the ants could exist. Huber tells us that the workers of this species perform no work save that of capturing slaves. Use and wont, and the habit of depending entirely on their servitors, have produced such changes in the structure of the ants that they are unable to help themselves. The jaws of these ants are not adapted for work; they are carried by their slaves from an old nest to a new one; and, more extraordinary still, they require to be fed by their slaves, even with plenty of food close at hand. Out of thirty of these ants placed by Huber in a box, with some of their larvae and pupae, and a store of honey, fifteen died in less than two days of hunger and of sheer inability to help themselves. When, however, one of their slaves was introduced, the willing servitor "established order, formed a chamber in the earth, gathered together the larvae, extricated several young ants that were ready to quit the condition of pupae, and preserved the life of the remaining Amazons." It must be noted that there are very varying degrees in the dependence of the ant-masters on their slaves. In the recognition of this graduated scale of relationship and dependence, indeed, will be found the clue to the acquirement of this instinct. The horse-ant (Formica rufa) will carry off the larvae and pupae of other ants for food, and it sometimes happens that some of these captives, spared by their cannibal neighbors, will grow up in the nest of their captor. A well-known ant, the Formica sanguinea, found in the South of England, is however, a true slave-making species, but exhibits no such utter dependence on its servitors as does Polyergus. The slave-making habit is not only typically developed in the Sanguineas, but the bearing of the captives to their masters indicate a degree of relationship and organization such as could hardly be conceived to exist outside human experience. The Sanguineas make periodical excursions, and, like a powerful predatory clan, carry off the pupae or chrysalides of a neighboring species, F. fusca. Thus the children of the latter race are born within the nest of their captors in an enslaved condition. As slaves "born and bred," so to speak, they fall at once into the routine of their duties, assist their masters in the work of the nest, and tend and nurse the young of the family. The slaves, curiously enough in this instance, are black in color, whilst the masters are twice the size of the servitors, and are red in color, and that the slaves are true importations is proved by the fact that males and females of the slave species are never developed within the nest of the masters, but only within those of their own colonies. The slaves in this instance rarely leave the nest, the masters foraging for food, and employing their captives in household work, as it were; whilst, when the work of emigration occurs, the masters carry the slaves in their mouths like household goods and chattels, instead of being carried by them, as in the case of Polyergus.

Mr. Darwin gives an interesting account of the different attitudes exhibited by the Sanguineas toward species of ants other than the black race from which their slaves are usually drawn. A few pupae of the yellow ant (F. flava), a courageous and pugnacious little species, were placed within the reach of the slave-making Sanguineas. A like chance presented with the pupae of their slave race was eagerly seized, and the chrysalides carried off. The pupae of the yellow ants, however, were not merely left untouched, but the slave-makers exhibited every system of terror and alarm at the sight of the chrysalides of their yellow neighbors. Such an instance demonstrates the existence not merely of perception but also of the memory of past experience, probably of not over agreeable kind, of encounters with the yellow ants. When, on the contrary, a nest of the slaves is attacked, the Sanguineas are both bold and wary. Mr. Darwin traced a long file of Sanguineas for forty yards backward to a clump of heath, whence he perceived the last of the invaders marching homeward with a slave pupa in its mouth. Two or three individuals of the attacked and desolate nest were rushing about in wild despair, and "one," adds Mr. Darwin, "was perched motionless, with its own pupa in its mouth, on the top of a spray of heath, an image of despair over its ravaged home." The picture thus drawn is not the less eloquent because its subject is drawn from lower existence; although the pains and sorrows of ant life may not legitimately be judged by the standard of human woe.

The explanation of the slave-making instinct in ants begins with the recognition of the fact that many ants, not slave-makers, store up pupae of other species for food. If we suppose that some of the pupae, originally acquired through a cannibal-like instinct, came to maturity within the nest of their captors, and in virtue of their own inherited instincts engaged in the work of the hive, we may conceive of a rational beginning of the slave-making instinct. If, further, the captors learned to appreciate the labors of their captives, as lightening their own work, the habit of collecting pupae as slaves might succeed and supersede that of collecting them for food. In any case, we should require to postulate on the part of the slave-makers a degree of instinct altogether unusual in insects, or, indeed, in higher animals; but that such instinct is developed in ants other than slave-makers admits of no dispute. The strengthening, through repetition, of a habit useful to the species may thus be credited with the beginning of the practice of slavery amongst ants; whilst special circumstances—such as the number of the slaves as compared with the number of masters—would tend to develop a greater or less degree of dependence of the captors or their servitors.

Huber, for instance, informs us that the Fusca-slaves of the Sanguineas of Switzerland work with their masters in building the nest; they close and open the doors of the hive; but their chief office appears to be that of hunting for plant-lice. In England, on the contrary, the slaves are strictly household servants, rarely venturing out of doors. Such differences depend most probably on the fact that a greater number of slaves occur in Swiss than in English nests, and they may therefore be employed in a wider range of duties on the Continent than at home. A fewer number of slaves, a greater aptitude on the part of the slaves for their duties, the inability of the masters to perform the duties of the slaves—each or all of these causes combined would serve to increase the value of the servitors, and at the same time to reduce the independence of the masters.

This increase of the value of the slaves as active factors in the ant community might at length proceed to such extremes as we see exemplified in the Polyergus, already referred to—a race which has become literally unable to feed itself, and to discharge the simplest duties of ant existence, and whose actual life is entirely spent in marauding expeditions on the nests of its neighbors.

The subject of the general intelligence of ants, and of their ability to adapt themselves to awkward and unusual circumstances, may be briefly touched upon by way of conclusion.

Between the reason and intelligence of higher animals and the "instinct" of ants there is unquestionably a great gulf fixed. I make this statement unhesitatingly, notwithstanding that I should no more willingly attempt to define "instinct" than to give an exact definition of "insanity." In the latter case one may make the definition so limited as practically to exclude all save one class of cases, or so wide as to include even the judge on the bench. In the case of instinct, the rigid definition of one authority might cause us to regard it as the exclusive property of lower forms and as having no relationship whatever with the mental powers of higher beings; or, on the other hand, as being but a modified form of, or in some respects identical with, these very powers. We know too little respecting the so-called "automatic" powers and ways, even of higher animals, to dogmatize regarding the acts of lower animals, but we may safely assume that one apparent ground or distinction between instinct and reason may be found in the common incompetence of instinct to move out of the beaten track of existence, and in the adaptation of reason, through the teachings of experience, to new and unwonted circumstances. Let Dr. Carpenter speak as an authority on such a subject. "The whole nervous system of invertebrated animals, then, may be regarded as ministering entirely to automatic action; and its highest development, as in the class of insects, is coincident with the highest manifestations of the 'instinctive' powers, which, when carefully examined, are found to consist entirely in movements of the excito-motor and sensori-motor kinds. (The terms 'excito-motor' and 'sensori-motor' are applied to nervous actions resulting in movements of varying kinds, and produced by impressions made on nervous centres, but without any necessary emotion, reason, or consciousness.) When we attentively consider the habits of these animals, we find that their actions, though evidently adapted to the attainment of certain ends, are very far from evincing a designed adaptation on the part of the beings that perform them.... For, in the first place, these actions are invariably performed in the same manner by all the individuals of a species, when the conditions are the same; and thus are obviously to be attributed rather to a uniform impulse than to a free choice, the most remarkable example of this being furnished by the economy of bees, wasps, and other 'social' insects, in which every individual of the community performs its appropriated part with the exactitude and method of a perfect machine. The very perfection of the adaptation, again, is often of itself a sufficient evidence of the unreasoning character of the beings which perform the work; for if we attribute it to their own intelligence, we must admit that this intelligence frequently equals, if it does not surpass, that of the most accomplished Human Reasoner."

Appealing to the most recent observations on ants, we may find evidence of the truth of Dr. Carpenter's statements, whilst at the same time we may also detect instances of the development of higher powers which are hardly to be classed as "automatic," and which, in certain species (as in the Ecitons, charmingly described by Mr. Belt in "The Naturalist in Nicaragua"), may be said to be elevated above the common instincts of the race. Dr. Henry Maudsley has also well summed up the relationship of the acts of these insects to the acts of higher forms, and to new adaptations when he says: "I do not say that the ant and the bee are entirely destitute of any power of adaptation to new experiences in their lives—that they are, in fact, purely organized machines, acting always with unvarying regularity; it would appear, indeed, from close observation, that these creatures do sometimes discover in their actions traces of a sensibility to strange experiences, and of corresponding adaptations of movements. We cannot, moreover, conceive how the remarkable instincts which they manifest can have been acquired originally, except by virtue of some such power. But the power in them now is evidently of a rudimentary kind, and must remain so while they have not those higher nerve-centres in which the sensations are combined into ideas, and perceptions of the relations of things are acquired. Granting, however, that the bee or ant has these traces of adaptive action, it must be allowed that they are truly rudiments of functions, which in the supreme nerve-centres we designate as reason and volition. Such a confession might be a trouble to a metaphysical physiologist, who would thereupon find it necessary to place a metaphysical entity behind the so-called instincts of the bee, but can be no trouble to the inductive physiologist—he simply recognizes an illustration of a physiological diffusion of properties, and of the physical conditions of primitive volition, and traces in the evolution of mind and its organs, as in the evolution of other functions and their organs, a progressive specialization and increasing complexity."

The recently published experiments of Sir John Lubbock show that ants under certain circumstances are both stupid and devoid of any intelligent comprehension in the way of surmounting difficulties; but this distinguished observer has also shown that as regards communication between ants, and in the regulation of the ordinary circumstances of their lives, these insects evince a high degree of intelligence, and exhibit instincts of a very highly developed kind. Still, making every allowance for the development of extraordinary mental power in some species of ants, there can be little doubt of the purely automatic beginnings and nature of most, if not all, of the acts of ordinary ant existence. The young ant, wasp, or bee, will begin its labors and discharge them as perfectly at the beginning of its existence as a perfect insect, as at the close of life. Here there is no experience, no tuition, no consciousness, no reason, and no powers save such as have been transferred to the insect as a mere matter of heredity and derivation from its ancestors, who lived by an unconscious rule of thumb, so to speak. It is very hard at first to convince one's self, when watching an ant's nest, that intelligence and consciousness play little or no part in the apparently intelligent operation of these insects. But to assume the contrary would be to maintain that the insect stands on an equal footing to man himself, and for such a supposition there is neither lawful ground nor sympathy. The marvellous instinct of lower life stands on a platform of its own, has its own phases of development, and probably its own unconscious way of progress. The higher reason and intellect of humanity similarly possesses its own peculiar standard, rate, and method of culture. A man may seek and find in the ways of lower existence not merely a lesson in the ordering of his existence, but some comfort, also, in the thought that the progress of lower nature is not unknown in the domain of human hopes and aspirations.



THE WILD LLAMA

(FROM A JOURNAL OF RESEARCHES, ETC.)

BY CHARLES DARWIN.



The guanaco, or wild Llama, is the characteristic quadruped of the plains of Patagonia; it is the South American representative of the camel in the East. It is an elegant animal in a state of nature, with a long slender neck and fine legs. It is very common over the whole of the temperate parts of the continent, as far south as the islands near Cape Horn. It generally lives in small herds of from half a dozen to thirty in each; but on the banks of the St. Cruz we saw one herd which must have contained at least five hundred.

They are generally wild and extremely wary. Mr. Stokes told me, that he one day saw through a glass a herd of these animals which evidently had been frightened, and were running away at full speed, although their distance was so great that he could not distinguish them with his naked eye. The sportsman frequently receives the first notice of their presence, by hearing from a long distance their peculiar shrill neighing note of alarm. If he then looks attentively, he will probably see the herd standing in a line on the side of some distant hill. On approaching nearer, a few more squeals are given, and off they set at an apparently slow, but really quick canter, along some narrow beaten track to a neighboring hill. If, however, by chance, he abruptly meets a single animal, or several together, they will generally stand motionless and intently gaze at him; then perhaps move on a few yards, turn round, and look again. What is the cause of this difference in their shyness? Do they mistake a man in the distance for their chief enemy the puma? Or does curiosity overcome their timidity? That they are curious is certain; for if a person lies on the ground, and plays strange antics, such as throwing up his feet in the air, they will almost always approach by degrees to reconnoitre him. It was an artifice that was repeatedly practised by our sportsmen with success, and it had moreover the advantage of allowing several shots to be fired, which were all taken as parts of the performance. On the mountains of the Tierra del Fuego, I have more than once seen a guanaco, on being approached, not only neigh and squeal, but prance and leap about in the most ridiculous manner, apparently in defiance as a challenge. These animals are very easily domesticated, and I have seen some thus kept in northern Patagonia near a house, though not under any restraint. They are in this state very bold, and readily attack a man by striking him from behind with both knees. It is asserted that the motive for these attacks is jealousy on account of their females. The wild guanacos, however, have no idea of defence; even a single dog will secure one of these large animals, till the huntsman can come up. In many of their habits they are like sheep in a flock. Thus when they see men approaching in several directions on horseback, they soon become bewildered, and know not which way to run. This greatly facilitates the Indian method of hunting, for they are thus easily driven to a central point, and are encompassed.



The guanacos readily take to the water: several times at Port Valdes they were seen swimming from island to island. Byron, in his voyage, says he saw them drinking salt water. Some of our officers likewise saw a herd apparently drinking the briny fluid from a salina near Cape Blanco. I imagine in several parts of the country, if they do not drink salt water, they drink none at all. In the middle of the day they frequently roll in the dust, in saucer-shaped hollows. The males fight together; two one day passed quite close to me, squealing and trying to bite each other; and several were shot with their hides deeply scarred. Herds sometimes appear to set out on exploring parties; at Bahia Blanca, where, within thirty miles of the coast, these animals are extremely unfrequent, I one day saw the tracks of thirty or forty, which had come in a direct line to a muddy salt-water creek. They then must have perceived that they were approaching the sea, for they had wheeled with the regularity of cavalry, and had returned back in as straight a line as they had advanced. The guanacos have one singular habit, which is to me quite inexplicable; namely, that on successive days they drop their dung in the same defined heap. I saw one of these heaps which was eight feet in diameter, and was composed of a large quantity. This habit, according to M. A. d'Orbigny, is common to all the species of the genus; it is very useful to the Peruvian Indians, who use the dung for fuel, and are thus saved the trouble of collecting it.

The guanacos appear to have favorite spots for lying down to die. On the banks of the St. Cruz, in certain circumscribed spaces, which were generally bushy and all near the river, the ground was actually white with bones. On one such spot I counted between ten and twenty heads. I particularly examined the bones; they did not appear, as some scattered ones which I have seen, gnawed or broken, as if dragged together by beasts of prey. The animals in most cases must have crawled, before dying, beneath and amongst the bushes. Mr. Byron informs me that during a former voyage he observed the same circumstances on the banks of the Rio Gallegos. I do not at all understand the reason of this, but I may observe, that the wounded guanacos at the St. Cruz invariably walked towards the river. At St. Jago in the Cape de Verd islands, I remember having seen in a ravine a retired corner covered with bones of the goat; we at the time exclaimed that it was the burial-ground of all the goats in the island.



BATS

(FROM STUDIES OF ANIMATED NATURE.)

BY W. S. DALLAS, F.L.S.



Among the sounds which greet the ear of the wayfarer as the shades of evening deepen into night, one of the commonest is a rather faint chirping noise which comes mysteriously from overhead. On looking up in search of the source of this peculiar sound, we may see a small, dark, shadow-like creature sweeping to and fro with great rapidity. It is one of the curious groups of animals called Bats, representatives of which are to be met with in in all countries, always active at night or in the twilight, and presenting a remarkable general similarity of structure, although in some respects they may differ considerably in habits. In the British Islands some fourteen species have been distinguished.

Like the owls, with which they share the dominion of the evening air, the Bats have a perfectly noiseless flight; their activity is chiefly during the twilight, although some species are later, and in fact seem to keep up throughout the whole night. As they rest during the day, concealed usually in the most inaccessible places they can find, and are seen only upon the wing, their power of flight is their most striking peculiarity in the popular mind, and it is perhaps no great wonder that by many people, both in ancient and modern times they have been regarded as birds. Nevertheless, their hairy bodies and leathery wings are so unlike anything that we ordinarily understand as pertaining to a bird, that opinion was apparently always divided, as to the true nature of these creatures—"a mouse with wings," as Goldsmith called it once, according to James Boswell, is certainly a curious animal, and very difficult to classify so long as the would-be systematist has no particularly definite ideas to guide him. The likeness of the Bat to a winged mouse has made itself felt in the name given to the creature in many languages, such as the "Chauvesouris" of the French and the "Flitter-mouse" of some parts of England, the latter being reproduced almost literally in German, Dutch, and Swedish, while the Danes called the Bat a "Flogenmues," which has about the same meaning, and the Swedes have a second name, "Laedermus," evidently referring to the texture of the wings, as well as to the mouse-like character of the body.

But so soon as we have definite characters to appeal to in classification, we find no difficulty in assigning these puzzling creatures to their proper place in the system. Bats produce their young alive, and suckle them; the milk being produced by special glands. Now, these are characters which are peculiar among all animals to the vertebrate class Mammalia. They possess also other characters that are unmistakably mammalian. Leaving out of consideration the structure of the internal organs, they have teeth implanted in sockets in the jaws, four limbs, and a hairy covering to the skin, so that they possess more decidedly mammalian characters than some other members of the class, such as the marine whales and dolphins (Cetacea) and manatees (Sirenia), which are still often spoken of as fishes. In point of fact, although organized for flight, the Bat may, without any violence to language, be spoken of as a quadruped, for its fore-limbs contain all the parts found in those of other mammals fully developed, and they come into use when the creature is walking on the ground.

Perhaps the special characteristics of the Bats will be brought out most distinctly by a comparison of their structure with that of a bird, seeing that the modification of the fore-limbs into wings is their most striking distinction from other Mammalia; for, although some other members of the class are spoken of as "flying," such as the Flying Squirrels, Flying Lemurs, and Flying Phalangers, these creatures do not really fly, but merely glide through the air to considerable distances by the action of a broad fold of skin which runs down each side of the body, and which, when stretched between the extended limbs, buoys the creatures up in the air after the fashion of a parachute.

Most of us must have had occasion to pick the bones of a bird's wing, a piece of practical anatomy which may serve us in good stead at present. They consist of a long bone, which may be called the arm-bone (humerus), jointed to the shoulder-bones (the so-called "side-bones" of a fowl or turkey), followed by a pair of parallel bones constituting the fore-arm, at the end of which we find two or three small bones, then two parallel bones united at their extremities, and some smaller joints terminating the whole.

We need say nothing about the arm-bone and the two bones of the fore-arm, the peculiarity of bird-structure lying chiefly in the terminal portion of the limb, or the hand. Here we find, after two little bones forming the wrist, a pair of long bones as above described, firmly united both at base and apex, and on the outside of the base of these, close to the wrist, a small bone, which may be either free or soldered to the others, and which represents the thumb in the human hand. At the other end of the piece formed by the two united bones, the limb is continued by two joints, forming a second finger, inside of which there is usually a single small bone, representing a third finger. But all these parts are stiffly attached to one another, admitting of very little motion, so that the whole hand forms as it were a single piece. The bony structure of the bird's wing is in point of fact a rod hinged in two places, at the elbow and the wrist, for the convenience of being folded into a small compass. The flight of the bird is effected by the agency of a number of stiff feathers implanted in the skin covering the bones and muscles of the arm and hand; these fold together like the sticks of a fan when the wing is folded, and are spread into an elastic instrument for striking the air when the different sections of the bony framework are extended by the action of their respective muscles.

In the Bat the structure is very different. Of course, as in the Vertebrata generally, we find in the Bat's fore-limb the same three main sections as in birds; and as the function of the limb is the same, and a certain stiffness is necessary in the extended organ, the movements of the joints at the elbow and wrists are hinge-like. But the bones of the arm and fore-arm are longer and more slender, especially the latter; and in this part, in place of the two parallel bones of the bird's wing, we find in the Bat only a single long bone representing the smaller bone of the bird, the larger one being usually reduced to very small dimensions, and firmly united with the other into a single piece, although it still forms the elbow-joint. At the other end of this long fore-arm we find some small wrist-bones and to these the fingers are articulated. In birds, as we have seen, only two or three fingers are represented, and these are more or less reduced in size, and the most important of them soldered together; Bats, on the contrary, show the whole five fingers as distinctly as in the hand of man or any other mammals. The first of them, or the thumb, is short, slender, and flexible, and composed of three joints; the other four are very long and slender, but chiefly composed of the metacarpal bones, corresponding to those of the palm of the human hand. The first, or index finger, indeed, in many Bats, consists of this bone alone; but in the others it is followed by two or three slender joints, gradually tapering to the extremity, the second finger, corresponding to our middle finger, being always the longest of all.

Just as is the bird's wing, these various parts can be folded together or extended by the action of the muscles, but in the Bat the long fingers become separated when the wing is stretched out, and by this action they at the same time stretch a thin leathery double membrane in which they are enclosed, which is thus converted into a broad surface for striking the air in flight. This membrane is continued from the fingers to the sides of the body, and even to the hind limbs, which are often included in it to the ankle-joints; while in the great majority of Bats there is even a further portion of membrane between the hind legs, enclosing the whole or a portion of the tail. There is usually also a narrow strip of the same membrane in front of each arm, so that the skin of the animal is extended as much as possible, in order to give it support in its aerial evolution. It is to be noted that the long second finger extends to the extreme point of the wing and that the first finger runs close beside it and thus assists in stiffening that part of the organ. The thumb is left free, and is furnished with a rather strong hooked claw.

Supported by the action of these great leathery wings, the Bat flies about almost incessantly during the twilight, and often late into the night. In full career its flight is swift, though perfectly noiseless, and it has the power of executing rapid turns and changes of direction with the greatest facility, as required for the capture of its prey, which, in the great majority of cases, consists of the insects of various kinds that in most places fly by night. In pursuit of these, the Bats flit rapidly about trees, houses, and other buildings, now and then resting by clinging for a moment to the rough surfaces of the walls or the trunks and branches of trees. Old country church-yards, which are usually full of trees, are naturally favorite haunts of these nocturnal insect-hunters, offering them an excellent field for the chase of their prey, while at the same time, the church itself, with its architectural peculiarities, usually affords them a safe retirement during the day in the dark and secluded corners of its structure. Hence in the popular mind the Bat has long been associated with the church-yard, that spot so dreaded that few can pass through it after nightfall without experiencing certain peculiar feelings, so that it is no great wonder if a portion of the superstitious fear thus engendered has transferred itself to these frail and harmless creatures, and given them and their companions, the owls, something of an evil reputation. And it must be confessed that when seen against the light, flitting silently overhead, there is something weird in the Bat's form, and this is no doubt the reason why, while angels of all kinds are represented with birds' wings, those of Bats have, by universal consent, always been conferred upon demons, dragons, and similar uncanny creatures.

When it descends from its flight upon the ground or any solid body, the Bat becomes to all intents and purposes a genuine quadruped. The fingers being drawn together, with the membranes of the wings thrown into folds between them, the whole hand of the creature is brought up parallel to the fore-arm, and so got out of the way, and the animal can then walk more or less easily, its hind legs, though short and rather feeble, being perfectly formed, and the fore limbs, from which the thumbs with their sharp claws now project freely, becoming available for terrestrial progression. Nevertheless, this progression is generally rather clumsy, as indeed might be expected from creatures so curiously constructed.

While on the wing, our Bats are constantly engaged in the pursuit of the numerous insects of various kinds which, like themselves, are active in the evening and after dark, and of these they must destroy immense quantities. The swarms of delicate gnats and midges which disport themselves in the most complicated aerial dances, moths of all kinds, and even the hard-shelled beetles, many of which fly about in the evening or at night, fall a prey to these leathern-winged rovers of the night air, and weak as the latter would seem to be, some of them are able to seize and devour beetles which appear to be far beyond their powers. Thus, the largest of our British species, the Great Bat, or Noctule (Scotophilus noctula), which, however, is only about three inches in length, preys freely upon such large and hard-shelled insects as cockchafers; these, in fact, appear to be its favorite food, and for their consumption its broad and comparatively strong jaws would seem to be specially fitted, while its large and powerful wings, measuring fourteen or fifteen inches from tip to tip when expanded, enable it to fly with the rapidity necessary for the pursuit and capture of such powerful prey. When thus engaged, the Noctule haunts the neighborhood of trees, and generally flies at a considerable elevation, from which, however, his shrill cry easily reaches the ear of the passer-by. His addiction to large prey gives rise to a curious movement, thus noticed by Professor Bell in his valuable book on "British Quadrupeds." "An observer will not watch his movements long," says the Professor, "without noticing a manoeuvre which at first looks—like the falling of a tumbler-pigeon, but on closer examination proves to be simply a closing of the wings, and a consequent drop of about a foot. Sometimes, this is repeated every few yards, as long as in sight. It is occasioned by some large and intractable insect having been captured, and the anterior joint of the wing, with its well-armed thumb, is required in retaining it until masticated." Notwithstanding this little difficulty, however, the Noctule is pretty rapid in disposing even of his most recusant prey, as he has been known to consume as many as thirteen cockchafers one after another.

The foregoing statements apply to all our British Bats, and indeed, in the matter of food and general habits, to the great majority of the species of the order, in whatever country they may occur. But in the tropical and sub-tropical regions of the eastern hemisphere, we find a great and important group of Bats, which, although agreeing in general structure and habits with our European species, differ from them altogether in their diet. These Bats, distinguished generally, among other things, by their larger size and more robust construction, and by certain characters of the molar teeth (grinders), from the ordinary Bats, are almost exclusively confined to a fruit diet, in search of which they fly vigorously, often in flocks, like birds, at the commencement of the night. From this peculiarity of their food they are commonly known as Fruit Bats, while the larger species, such as the Indian Fruit Bat and the Kalong of the Eastern Archipelago, which are respectively eleven and fourteen inches in length, are sometimes called Flying Foxes, in allusion to the prevalence of a reddish tint in their fur, and their more or less lengthened and dog-like muzzles. In many parts of the Eastern world, in India, the Malayan Archipelago, Australia, Africa, and even in outlying islands at some distance from their main range, these Fruit Bats occur in great numbers. Swarms of them roost together during the day, hanging from the branches of the trees which they select as their regular resting-place, and taking wing at sunset, fly off frequently to great distances in search of their favorite articles of food; for they by no means devour indiscriminately any kind of fruit, but show a distinct preference for particular sorts, generally selecting such as are also prized by their human competitors. Hence they often do considerable damage in plantations of fruit trees, as when they meet with articles that suit taste, they seem, like some human gourmands, not to know when to leave off eating. Of one of the smaller Indian species, the Margined Fruit Bat, Mr. Dobson obtained a living specimen in Calcutta, and he gives the following account of its voracious appetite:—He gave it "a ripe banana, which, with the skin removed, weighed exactly two ounces. The animal immediately, as if famished with hunger, fell upon the fruit, seized it between the thumbs and the index fingers, and took large mouthfuls out of it, opening the mouth to the fullest extent with extreme voracity. In the space of three hours the whole fruit was consumed. Next morning the Bat was killed, and found to weigh one ounce, half the weight of the food eaten in three hours! Indeed, the animal when eating seemed to be a kind of living mill"—so continuously does its food pass through it.

From the statements of some writers, it would appear that although these Bats live chiefly upon fruits, they occasionally, like many other frugivorous animals, diversify their diet with animal food, devouring insects of various kinds, caterpillars, birds' eggs, and even young birds, while there seems to be some reason to believe that one species even feeds upon shell-fish which it picks up upon the seashore.

The fruit-eating Bats of this group are not found in the warmer parts of America, but some American Bats feed chiefly upon fruits, while many of the large essentially insectivorous species which occur there vary their diet more or less with fruits, and also occasionally attack and devour other vertebrate animals. Some of them—but it is still very doubtful how many—have another habit connected with their feeding, which renders them very decidedly objectionable, namely, that of inflicting wounds upon birds and mammals, even including man himself, and sucking up the blood that flows from them. This charge has been brought against many Bats of South and Central America, some of which have been commonly named Vampires in consequence, after the ghostly blood-suckers, which were formerly the objects of so much superstitious terror in Hungary and other parts of Eastern Europe; but so far as can be made out from a consideration of the evidence, a verdict of "not proven," at all events, must be arrived at in the case of all but two species, which constitute a little group distinguished by what is apparently a special organization adapting them to this peculiar diet. These wretched little beasts, which only measure two and a half or three inches in length, are furnished in the upper jaw with a single pair of incisor or front teeth, but these are of great size and strength, triangular in form, and so excessively sharp that when the creatures are seized they can draw blood from the hand of their captor by what seems a mere touch. This extreme sharpness of their weapons enables them, when attacking sleeping men or animals, to slice off a small portion of skin almost without causing any pain, and the little oval wounds thus produced, like the similar surface-cuts which a careless shaver sometimes inflicts upon his chin, bleed with particular freedom. The Desmodonts, as these true Vampires are called, will attack horses, mules, and cattle, which they generally wound on the back, near the spine, often in the region of the withers; and they also bite the combs of domestic fowls, and any part of the human body that they can get at. In the case of man, however, according to most authorities, the extremity of the great toe is the favorite part; and some writers, perhaps possessed of a strong poetical vein, have given wonderful descriptions of the artfulness with which these little blood-suckers make their approaches, and keep their victim comfortably asleep during the operation by fanning him with their wings. In fact, the Vampire Bats had so bad a reputation from the accounts given by travellers, that they seemed to be veritable scourges of the countries in which they live, but so far as can be made out from the most trustworthy reports, the mischief they cause may be summed up under two heads, namely, weakness produced by loss of blood, which continues to flow from the wounds long after the Bats have drunk their fill and gone quietly home to rest, and inflammatory affections, caused either by the irritation of the bite in the case of people of a bad habit of body, or by the friction of the saddle or collar upon the part bitten in the case of horses and mules, or of the shoe in the human patient. That the Desmodonts do really feed on blood is proved by evidence of various kinds. They have been captured in the act of blood-sucking, when their stomachs, which are peculiarly constructed and very long, are found filled with a black paste, which is evidently half-digested blood; and their teeth, which are in part so well adapted for producing the necessary wounds in other animals, are totally unfit for the mastication of an insect prey, such as constitutes the diet of their nearest allies.



After all this feeding, Bats, whatever the nature of their diet, not unnaturally find themselves inclined for repose, and as they are active during the night or in the twilight, of course their rest has to be taken in the daytime. To pass the period of repose in security they seek shelter of various kinds, not only for protection against the weather, but also for the sake of concealment from other predaceous animals, some of which would no doubt be perfectly willing to make a meal of them. The great Eastern Fruit Bats, trusting perhaps to their size and strength, are content to resort to the branches of trees, from which, after the manner of Bats in general, they suspend themselves by the hind feet with the head downwards. From the statements of various writers it appears that after being out all night in search of food, the Flying Foxes and other allied Bats fly back to their regular resting-places, where they begin to arrive about or soon after dawn. The number resorting to the same retreat is usually so great that the whole of the branches are loaded with them, and in fact they are so crowded together that the settling down of the flock into their repose is preceded by a scene of squabbling and quarrelling of the most noisy description. Mr. Tickell, speaking of the common Indian Flying Fox, says:—"From the arrival of the first comer, until the sun is high above the horizon, a scene of incessant wrangling and contention is enacted among them, as each endeavors to secure a higher and better place, or to eject a neighbor from too close vicinage. In these struggles the Bats hook themselves along the branches, scrambling about hand over hand with some speed, biting each other severely, striking out with the long claw of the thumb, shrieking and cackling without intermission. Each new arrival is compelled to fly several times round the tree, being threatened from all points; and when he eventually hooks on, he has to go through a series of combats, and be probably ejected two or three times, before he makes good his tenure." This scene of selfish contention over, the Fruit Bats pass some hours in profound sleep, during which they remain suspended in rows along the branches, to which they cling by one foot only, the other with all the lower surface of the body being comfortably wrapped in the leathery mantle formed by the contracted wings. In this condition, as Dr. Horsfield says of the Great Kalong, "ranged in succession with the head downwards ... and often in close contact, they have little resemblance to living beings, and by a person not accustomed to their economy are easily mistaken for a part of the tree, or for a fruit of uncommon size suspended from its branches." In this position the head is folded down upon the breast. Dr. Bennett and Mr. Gould ascribed very similar habits to a large Fruit Bat common in the northern parts of New South Wales and in Queensland, which is said to be often exceedingly destructive to the peach and other fruit crops of the settlers in those colonies.

The European Bats, and indeed all the Bats except these Flying Foxes and their immediate allies, seek a different kind of shelter. Their chief natural dormitories consist of hollow trees and the caves and fissures of rocks, to which they often resort in great numbers; but in populous countries they also find an abundance of convenient places of retirement in and about buildings of various kinds. Roofs, especially when covered with tiles, or otherwise provided with apertures through which the space immediately under the roofing is easily accessible, outbuildings of all kinds, church towers and other similar structures, disused chimneys, the spaces behind weather-boards and shutters which are not often moved, in fact any dark and sheltered places about our buildings, are readily resorted to by many species, although some few retain their taste for unadulterated nature so strongly that no artificial harbor will serve their turn. Thus among the British species the Great Bat or Noctule, a generally distributed though not abundant species throughout the southern and middle counties of England, seems generally to retreat for its diurnal sleep to the holes or cavities in the trunks of trees, and only to visit buildings when there is a scarcity of such accommodation; and the Horseshoe Bats show a decided preference for caverns and deserted quarries; but the great majority appear to be indifferent in the matter, and to resort to any shelter that seems convenient to them. Some, such as the Barbastelle of the southern parts of England, are solitary in their habits, generally retiring alone for their day's rest; others are more sociable, reposing in larger or smaller parties in their dormitories, whether natural or artificial, and sometimes, like the Fruit Bats, collecting in immense numbers.