The Industries of Animals
by Frederic Houssay
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The English edition of this book has been revised throughout and enlarged, with the author's co-operation. Numerous bibliographical references have also been added. The illustrations, when not otherwise stated, are in most cases adapted from Brehm's Thierleben.




The naturalists of yesterday and the naturalists of to-day—Natural history and the natural sciences—The theory of Evolution—The chief industries of Man—The chief industries of Animals—Intelligence and instinct—Instinctive actions originate in reflective actions—The plan of study of the various industries.



The Carnivora more skilful hunters than the Herbivora—Different methods of hunting—Hunting in ambush—The baited ambush—Hunting in the dwelling or in the burrow—Coursing—Struggles that terminate the hunt—Hunting with projectiles—Particular circumstances put to profit—Methods for utilising the captured game—War and brigandage—Expeditions to acquire slaves—Wars of the ants.



Flight—Feint—Resistance in common by social animals—Sentinels.



Provisions laid up for a short period—Provisions laid up for a long period—Animals who construct barns—Physiological reserves—Stages between physiological reserves and provisions—Animals who submit food to special treatment in order to facilitate transport—Care bestowed on harvested provisions—Agricultural ants—Gardening ants—Domestic animals of ants—Degrees of civilisation in the same species of ants—Aphis-pens and paddocks—Slavery among ants.



The preservation of the individual and the preservation of the species—Foods manufactured by the parents for their young—Species which obtain for their larvae foods manufactured by others—Carcasses of animals stored up—Provision of paralysed living animals—The cause of the paralysis—The sureness of instinct—Similar cases in which the specific instinct is less powerful and individual initiative greater—Genera less skilful in the art of paralysing victims.



Animals naturally provided with dwellings—Animals who increase their natural protection by the addition of foreign bodies—Animals who establish their home in the natural or artificial dwellings of others—Classification of artificial shelters—Hollowed dwellings—Rudimentary burrows—Carefully-disposed burrows—Burrows with barns adjoined—Dwellings hollowed out in wood—Woven dwellings—Rudiments of this industry—Dwellings formed of coarsely-entangled materials—Dwellings woven of flexible substances—Dwellings woven with greater art—The art of sewing among birds—Modifications of dwellings according to season and climate—Built dwellings—Paper nests—Gelatine nests—Constructions built of earth—Solitary masons—Masons working in association—Individual skill and reflection—Dwellings built of hard materials united by mortar—The dams of beavers.



General precautions against possible danger—Separation of females while brooding—Hygienic measures of Bees—Prudence of Bees—Fortifications of Bees—Precautions against inquisitiveness—Lighting up the nests.



Degree of perfection in industry independent of zoological superiority—Mental faculties of the lower animals of like nature to Man's.







The naturalists of yesterday and the naturalists of to-day.—The study of animals, plants, rocks, and of natural objects generally, was formerly called "natural history"; but this term is tending to disappear from our vocabulary and to give place to the term "natural sciences." What is the reason of this change, and to what does it correspond? for it is rare for a word to be modified in so short a time if the thing designated has not itself varied.

Exterior forms have certainly changed, and the naturalist of yesterday makes upon us the impression of a legendary being. I refer to the person described in George Sand's romances, marching vigorously over hills and valleys in search of a rare insect, which he pricked with delight, or of a plant difficult to reach, which he triumphantly dried and fixed on a leaf of paper bearing the date of the discovery and the name of the locality. A herbarium became a sort of journal, recalling to its fortunate possessor all the wanderings of the happy chase, all the delightful sounds and sights of the country. Every naturalist concealed within him a lover of idylls or eclogues. Assuredly all the preliminary studies which resulted from these excursions were necessary; we owe gratitude to our predecessors, and we profit from their labours, sometimes regretting the loss of the picturesque fashion in which their researches were carried out.

The naturalist of to-day usually lives more in the laboratory than in the country. Occasional expeditions to the coast or dredgings are the only links that attach him to nature; the scalpel and the microtome have replaced the collector's pins, and the magnifying glass gives place to the microscope. When the observer begins to pursue his studies in the laboratory he no longer cares to pass the threshold. He has still so much to learn concerning the most common creatures that it seems useless to him to waste his time in seeking those that are rarer, unless he takes into account the unquestionable pleasure of rambling through woods or along coasts;—but such a consideration does not belong to the scientific domain.

A change of conditions of this nature does not suffice to create a science. To take away from a study all that rendered it pleasant and easy, and to make it the property of a small coterie, when it was formerly accessible to all, is not sufficient to render it scientific. It is a fatality rather than a triumph to have undergone such a change. The change is an effect rather than a cause.

When little or nothing was known it was necessary to begin by examining the phenomena which first met the eyes of the observer, such as the customs of animals and the characters which distinguished them from each other. Their differences and resemblances were studied; they were formed into groups, classed and arranged in an order recalling as much as possible their natural relations. In classifying it is impossible to consider all the facts or the result would be chaos; it is necessary to choose the characters and to give preponderance to certain of them. This sorting of characters has been executed with the sagacity of genius by the illustrious naturalists of the last century and the beginning of the present. But the frames which they have traced are fixed and rigid; nature with her infinite plasticity escapes from them. We render a great homage to the classifiers when we say that they have confined the facts as closely as it is possible to do. The catalogues which they have prepared are of a utility which is unquestionable, although their role is to be useful only; we cannot pretend to make them the expression, the symbol, the formula in which all natural phenomena are to be enclosed. To confound classification with science is to confound the lever with the effect which we expect from it.

Curiosity, moreover, always impels towards that which is least known. External appearances having been studied, the form and function of internal organs were investigated. Physiology and comparative anatomy were born and developed; researches abounded and observers abandoned the field for the laboratory.

The difference in methods of research and the pushing of precision to its extreme limits—an inevitable result of the different nature of the observations to be made—did not however yet render legitimate the claim for natural studies to be called "science."

Natural history and the natural sciences.—A more important event has taken place. The ancient naturalists, like their contemporaries, had firm beliefs which they used as unquestionable principles for the comprehension of all facts. The explanation of an observation was ready in advance. The study of facts invariably brought to the pen of the writer the same enthusiastic admiration of the marvellous part played by Providence in nature.[1] The phenomena in which this action was not strikingly apparent were merely described without any attempt to relate them with each other, or with the other facts. A hypothesis which left a great number of facts without explanation was necessarily insufficient. The descriptions, in spite of all their individual interest, did not constitute a homogeneous whole, a science. They were merely a collection of more or less natural histories.

[1] See, for example, Reaumur, Memoires pour l'histoire des Insectes, t. i., pp. 23-25.

Science only begins on the day when we have found the simple theory which binds together all the facts at that time known, without of course prejudicing the future. As the number of acquired facts increases, if the theory in question continues to explain the new as it explained the old, the science becomes more firmly established. If we can imagine a time arriving when all the possible phenomena are known, and the existing hypothesis still explains them, nothing henceforth can overturn it, the science is completed. That is the simple case in which a theory has been victorious; but if it is contradicted by a single well-authenticated fact it must fall or become modified. The more things a theory explains in the present the more chance it has of success in the future. It is still only a matter of chances, for the theory is always at the mercy of unforeseen observation, which may rudely overthrow it.

There is no theory which must not be modified constantly, at least in its details. To render it more and more general by successive improvements is the aim to be pursued. A collection of studies constitutes a science when a hypothesis has arisen already sufficiently strong to oblige us to refer to it all new acquisitions, and to compel us to see if they fortify or oppose it.

It would indeed be a narrow conception if we were to consider as scientific the partisans of the theory alone; more than anywhere else discussion is fruitful in the natural sciences; and if it is necessary to be constantly preoccupied with the general ideas of the day, it is not at all necessary to adhere to them servilely. The naturalists of to-day are in possession of a formula with which we must always preoccupy ourselves; in other words, there are natural sciences.

The theory of Evolution.—This hypothesis which comes before all others is the theory of evolution. This is not the place to expound it, to go over the proofs which have been amassed to build it up, nor the criticisms which have been directed against it. It has to-day come out of the struggle victoriously. A prodigious quantity of facts, of comparative anatomy and of embryology, inexplicable without it, emerge from the chaos and constitute a whole, truly and marvellously homogeneous. Issued from the natural sciences, the doctrine of evolution now overflows them and tends to embrace everything that concerns man: history, sociology, political economy, psychology. The moralists seek, and will surely find, compromises permitting ethical laws to endure the rule of this overwhelming hypothesis.

Without going too far back into history, let us look towards the end of the last century and the beginning of this. Cuvier, Lamarck,[2] and Geoffroy Saint-Hilaire,[3] all preoccupied with general ideas, were each trying to build up a doctrine. The theory of evolution was born beneath the pen of Lamarck, but immediately fell under the attacks of Cuvier.[4] It is to Darwin that the honour belongs of having rescued it from oblivion and of having initiated the movement which to-day rules the natural sciences. Studies in embryology and anatomy are rising without number beneath this impulse; and perhaps it may be said that these new sciences, so fruitful in results, absorb a little too much attention and leave in the shade subjects longer known, but which, however, gain new interest by the way they fit into present scientific theories.

[2] Philosophie zoologique, 2e edition, Paris, 1830; Histoire des Animaux sans Vertebres, Introduction, 1835.

[3] Philosophie anatomique, 1818; Zoologie generale, 1841.

[4] Le Regne Animal, 1829; Lecons d'Anatomie comparee, 2e edition, 1835-46.

I wish to speak of the manners of animals; the facts regarding them are of sufficient interest if we consider them one by one, and they become much more interesting when we attempt to show the close way in which they are bound together. Volumes would not suffice to exhaust the subject; but if the entire task is too considerable, I may at least hope to accomplish a part of it by treating of those facts which may be brought together under the common title of Animal Industries. Taken separately, they may be reproached with a certain anecdotal character, but we cannot fail to agree that taken altogether they constitute an important chapter in the sciences of life.

The chief industries of Man.—Let us first throw a rapid glance at the various stages which the civilisation and industry of Man have gone through before arriving at their present condition. To make clear these phases we might either follow the state of civilisation in any given country by tracing back the course of centuries, or else at a given epoch find out in different parts of the earth all the stages of human evolution. The savage men of to-day are not further advanced in their evolution than our own ancestors who have now gone to fossil. However it may be, Man, at first frugivorous, as his dentition shows as well as his zoological affinities, in consequence of a famine of fruit or from whatever other cause, gradually began to nourish himself with the flesh of other animals. To search for this fleeing prey developed in him the art of hunting and fishing. His intelligence, still feeble, was entirely concentrated on this one point: to seize on an animal and to feed on it, although neither his nails nor his teeth nor his muscles make it natural to him. To hunt, to fish, to defend his territory against the wild beasts who attacked it and himself, to drive back tribes of his fellows who would diminish his provisions, these were the first rudiments of the industry of Man. Having become more skilful, he obtained in an expedition more game than he could consume at once; he then kept near him living beasts in order to sacrifice them when hunger came. His reserve of animals increased; they became accustomed to live near him; and he took care of his larder. A flock was gradually constituted, and the owner learnt to profit from all the resources which it offered him, from milk to wool. Henceforth he became economical with his beasts, and moved about in order to procure for them abundance of grass and water. He was still always hunting and fighting; but there were now accessory industries, and he was especially occupied in the domestication of animals. Then it happened that he acquired a taste for a graminaceous grain—corn. To seek the blades one by one is not a very fruitful labour, and decidedly troublesome. Man collected a supply of them, cultivated them, possessed fields which he sowed and harvested. He was henceforth obliged to renounce his herds, which had become immense; for he could not leave the soil where his corn was ripening, if he wished to gather it himself, and his cattle were lacking pasture. The number of beasts diminished; bread had killed milk. Man only kept near him a small flock capable of feeding on a moderate territory. He abandoned his temporary shelters, tents of skin or of woven wool, and since he must henceforth live on the same piece of land, he constructed there a fixed dwelling. Such is, taken altogether, the genesis of the industry of the dwelling connected with the culture of the soil; to earlier periods corresponded the natural or hollowed cave and the woven tent.

The chief industries of Animals.—In a more or less perfect degree we find the same industries among animals generally. In order to make just comparisons, we ought especially to consider the methods of those who are not endowed with specially appropriated organs, for in this case their task is rendered too simple. To take an example. The Lion is certainly an incomparable hunter; but his whole organisation tends to facilitate the capture of living prey. His agility and the strength of his muscles enable him to seize it at the first leap before it can escape. With his sharp claws he holds it; his teeth are so keen and his jaw so strong that he kills it immediately; with such natural advantages what need has he of ingenuity? But in the case of the Wolf or the Fox it is quite another matter; they hunt with a veritable art which Man himself has not disdained, since he has taken as his associate their relative, the Dog. It is the same with the Eagle and the Crow. The latter, in order to seize the prey which he desires, needs much more varied resources than the great bird of rapine for whom nature has done everything.

We find among animals not only hunting and fishing but the art of storing in barns, of domesticating various species, of harvesting and reaping—the rudiments of the chief human industries. Certain animals in order to shelter themselves take advantage of natural caverns in the same way as many races of primitive men. Others, like the Fox and the Rodents, dig out dwellings in the earth; even to-day there are regions where Man does not act otherwise, preparing himself a lodging by excavations in the chalk or the tufa. Woven dwellings, constructed with materials entangled in one another, like the nests of birds, proceed from the same method of manufacture as the woollen stuffs of which nomad tribes make their tents. The Termites who construct vast dwellings of clay, the Beavers who build huts of wood and of mud, have in this industry reached the same point as Man. They do not build so well, no doubt, nor in so complex a fashion as modern architects and engineers, but they work in the same way. All these ingenious artisans operate without organs specially adapted to accomplish the effect which they reach. It is with such genuine industries that we have to deal, for the most part neglecting other productions, more marvellous in certain ways, which are formed by particular organs, or are elaborated within the organism, and are not the result of the intelligent effort of the individual. To this category belong the threads which the Spider stretches, and the cocoon with which the Caterpillar surrounds himself to shelter his metamorphosis.

Intelligence and instinct.—By attentive observation it is possible to find in animals all the intermediate stages between a deliberate reflective action and an act that has become instinctive and so inveterate to the species that it has re-acted on its body, and thus profoundly modified it so as to produce a new organ in such a way that the phenomena are accomplished as a simple function of vegetative life, in the same way as respiration or digestion.

If an individual is led to reproduce often the same series of actions it contracts a habit; the repetition may be so frequent that the animal comes to accomplish it without knowing it; the brain no longer intervenes; the spinal cord or the chain of ganglia alone govern this order of acts, to which has been given the name of reflex actions. A reflex may be so powerful as to be transmitted by heredity to the descendants; it then becomes an instinct.

Thus by its nature instinct does not differ from intelligence, but is intimately connected with it by a chain of which all the links may be counted. The most intelligent of beings, Man, performs actions that are purely mechanical; many indeed can with justice be called instinctive; and, on the other hand, an animal for whom an innate hereditary instinct is sufficient in ordinary life will give proof of intelligence and reflection if circumstances in which his instinct is generally efficacious become modified so that he can no longer profit by them. Among other ingenious experiments to show the supposed difference between instinctive and reflective acts, Fabre brings forward the following[5]:—The Chalicodoma, a hymenopterous relative of the Bees, constructs nests composed of cells formed of mud agglutinated with saliva. The cell once constructed, the insect begins to fill it with honey before laying an egg there. He returns with his booty and wishes to disburse himself in the nest, finds the cellule which he has to fill, and proceeds always in the same order: first, he plunges his head in the cell and disgorges the honey which fills his crop; secondly, he emerges from the cell, turns round, and lets fall the pollen which remains attached to his legs. Suppose that an insect has just disgorged his honey, the observer touches his belly with a straw; the little animal, disturbed in his operation, returns to it having only the second act to perform. But he re-commences the whole of his operations though having nothing more to disgorge; he again plunges his head into the cell and goes through a pretence of disgorging, then turns round and frees himself from the pollen. Although touched twice, thrice, or more frequently, he always repeats the first action before executing the second. It is, says Fabre, almost like the movement of a machine of which the wheelwork will not act until one has begun to turn the wheel which directs it.

[5] J. H. Fabre, Souvenirs entomologiques, Paris, 1879, pp. 275 et seq.

It is incontestable; but I would add, as this conscientious observer does not, that that does not prove that the intelligence of the insect differs essentially from ours; it is a simple question of degree. Look at a boy who is going to jump over a ditch: he begins by spitting into his hands and rubbing them one against the other before taking his spring. In what has this served him? It is not more intelligent than the gesture of the bee who first plunges his head in the cell before freeing his claws, although the first gesture is useless.[6]

[6] It should perhaps be added that while the boy's action is not consciously intelligent, it is by no means purposeless, and is therefore not quite parallel with the insect's. By vigorously irritating the sensory nerves of the hand the boy imparts a stimulus to his muscular system. His act belongs to a large group which has been especially studied by Fere. See his Sensation et Mouvement (1887), and Pathologie des Emotions (1892).

And, from another side, if nothing is more instinctive than the manner in which domestic Bees construct their cells of wax with geometric regularity, there are other circumstances in which these same insects give proof of remarkable reflection, sagacity, and intelligence in co-ordinating their actions in the presence of an event to which they are not accustomed, and in attaining an end which has presented itself by accident. Such are, for example, the arrangements which they make to defend their honey against the attacks of a great nocturnal Moth, the Death's Head. I shall have to revert to these facts.

We must not then regard instinct, as has often been done, as a rudiment of intelligence, susceptible or not of development; but much rather as a series of intelligent acts at first reasoned, then by their frequent repetition become habitual, reflex, and at last, by heredity, instinctive.

What the individual loses in individuality and in personal initiative, heredity restores to him in the form of instinct which is, as it were, the condensed and accumulated intelligence of his ancestors. He himself no longer needs to take thought either to preserve his life or to assure the perpetuation of his race. The qualities which he received at birth render reflection less necessary; thus species endowed with some powerful instinct seem not to be intelligent when they live sheltered from unforeseen events.

From one point of view instinct appears to be a degradation rather than a perfecting of intelligence, because the acts which proceed from it are neither so spontaneous nor so personal; but from another point of view they are much better executed, with less hesitation, with a slighter expenditure of cerebral force and a minimum of muscular effort. A habitual act costs us much less to execute than a deliberate and reflective act. It is thus that the constructions of bees are more perfect than those of ants; the former act by instinct, the latter reason their acts at each step.

Instinctive actions originate in reflective actions.—No doubt it may be said: It is a pure hypothesis thus to consider instinct as derived from intelligence; why not admit as well that instinctive acts have been such from the beginning—in other words, that species have been created such as we see them to-day? The preceding explanation, however, has the advantage of being in harmony with the general theory of evolution, which, whether true or not, so well explains the most complicated facts that for the present it must be accepted. For the rest, if it is not possible to appraise the psychic faculties possessed by the ancestors of existing animals we may at least observe certain facts which put us on the road of explanation.

An interesting member of the Hymenoptera, the Sphex, assures food for the early days of the life of its larvae in a curious way.[7] Before laying its eggs it seizes a cricket, paralyses it with two strokes of its sting—one at the articulation of the head and the neck, the other at the articulation of the first ring of the thorax with the second—each stab traversing and poisoning a nervous ganglion. The cricket is paralysed without being killed; its flesh does not putrefy, and yet it makes no movement. The Sphex places an egg on this motionless prey, and the larva which emerges from it devours the cricket. Here assuredly is a marvellous and certain instinct. One cannot even object that the strokes of the sting are inevitably directed to these points because the chitinous envelope of the victim offers too much resistance in other spots for the dart to penetrate, because here is the Ammophila, a near relative of the Sphex, which chooses for its prey a caterpillar. It is free to introduce its sting into any part of the body, and yet with extreme certainty it strikes the two ganglions already mentioned.[8]

[7] "Etude sur l'Instinct et les Metamorphoses des Sphegiens," Ann. Sc. Nat., iv. Serie, t. 6, 1856.

[8] P. Marchal, "Observations sur l'Ammophila affinis," Arch. de Zool. exper. et gener., ii. Serie, t. 10, 1892.

We cannot suppose that the insect has anatomical and physiological knowledge to inform it of what it is doing. The act is distinctly instinctive, and seems imprinted by a fatality involving no possible connection with intelligence. But let us suppose that the ancestors of these Hymenoptera have thus attacked crickets and killed (not paralysed) them with one or more wounds at any point. By chance some of these insects, either in consequence of their manner of attacking the prey or from any other cause, happen to deliver their blows at the points in question. Their larvae on this account are placed in more favourable conditions than those of their relatives whom chance has less well served; they will prosper and develop sooner. They inherit this habit, which gradually becomes through the ages that which we know. It is possible; but why, it may be asked, this hypothesis, apparently gratuitous, of strokes of the sting given at random? Are there any facts which render this explanation plausible? Assuredly. Thus the Bembex, which especially attacks Diptera to make them the prey of its larvae, throws itself suddenly on them and kills them with one blow in any part of the body. It is unable in this way to amass in advance sufficient provision for its larvae; the corpses would putrefy. It is obliged to return from time to time bearing new pasture.[9] Again, M. Paul Marchal, taking up the study of instinct in the Cerceris ornata,[10] has shown that in this species at least of Sphegidae the stings have not so considerable an effect. This insect attacks a wild bee, the Halictus. He strikes his victim with two or three strokes of the sting beneath the thorax, but the paralysis is not definite, perhaps on account of the nature of the venom, which is not identical in all species. The tortured creature may regain life at the end of some hours. Thus the Cerceris is obliged to destroy the upper part of the neck by repeated malaxation of that part for several minutes at a time. The effect of this second act, by injuring the cerebroid ganglia, is to render impossible the return of action; moreover, it permits the aggressor to satisfy personal gluttony, and to feed on the liquids of the organism of the vanquished, which is easy, because the dorsal blood-vessel passes at this level. It can thus satisfy a personal need while thinking of the future of the race.

[9] J. H. Fabre, Souvenirs entomologiques, pp. 225 et seq.

[10] "Etude sur l'Instinct du Cerceris ornata," Archives de Zoologie experimentale, ii. Serie, t. 5, 1887.

It has been said in this connection that in such cases the sure instinct with which these species were originally endowed has been distorted, but that is to admit some degree of variation; the hypothesis of degeneration is as gratuitous as the other, and if we go so far as to risk a hypothesis, it would be better to use it to explain facts and not to entangle them.

Plan of study of the various industries.—The different industries carried on by animals may be divided into a certain number of groups. In the case of each of these categories I propose to arrange the facts in such a way as to bring forward first those animals which, having no special organs, are obliged to exercise the greatest ingenuity, and then to indicate the facts which show how variations have arisen which enable other species to accomplish these acts with marvellous ease.

We will first examine the simplest industries: hunting and fishing, those industries of which the object is the immediate search for prey; and to these may be added those which are related to them as re-action is to action—that is to say, the industries of which the effect is to provide for the immediate safety of the individual.

Then in an exposition parallel to the march of progress followed by human civilisations, we shall study among animals the art of collecting provisions, of domesticating and exploiting flocks, of reducing their fellows to slavery.

Finally, we shall investigate the series of modifications which the dwelling undergoes, and we shall see how certain species, after having constructed admirably-arranged houses, know how to make them healthy, and how to defend them against attacks from without.




The Carnivora more skilful hunters than the Herbivora.—The search for food has necessarily been the cause of the earliest industries among animals. It is easy to understand that the herbivora need little ingenuity in seeking nourishment; they are so superior to their prey that they can obtain it and feed on it by the sole fact of an organisation adapted to its assimilation. They are, it is true, at the mercy of circumstances over which they have no control, and which lead to famine. The carnivora also may have to suffer from the absence of prey, but even in the most favourable seasons, and in the regions where the animals on which they live abound, it is necessary to them to develop a special activity to obtain possession of beings who are suspicious, prompt in flight, and as fleet as themselves. Thus it is among these that we expect to find the art of hunting most cultivated; especially if we put aside the more grossly carnivorous of them, whose whole organisation is adapted for rapid and effective results.

Different methods of hunting.—Like Man, some animals hunt in ambush or by coursing; others know how to overturn the desired victim by throwing some object at it. These profit by all the exterior circumstances which are capable of frightening the game, of stunning it, and of rendering capture easy. But it is by studying each separate feature that we shall best be able to observe the close way in which these industries are related to our own. It is impossible to bring forward all the facts relating to the search for prey among animals; we can only take a few as signposts which mark the road.

Hunting in ambush.—The most rudimentary method of hunting in ambush is simply to take advantage of some favourable external circumstance to obtain concealment, and then to await the approach of the prey. Some animals place themselves behind a tuft of grass, others thrust themselves into a thicket, or hang on to the branch of a tree in order to fall suddenly on the victim who innocently approaches the perfidious ambush. The Crocodile, as described by Sir Samuel Baker, conceals himself by his skill in plunging noiselessly. On the bank a group of birds have alighted. They search the mud for insects or worms, or simply to approach the stream to drink or bathe. In spite of his great size and robust appetite the Crocodile does not disdain this slight dish; but the least noise, the least wrinkle on the surface of the water would cause the future repast to vanish. The reptile plunges, the birds continue without suspicion to come and go. Suddenly there emerges before them the huge open jaw armed with formidable teeth. In the moment of stupor and immobility which this unforeseen apparition produces a few imprudent birds have disappeared within the reptile's mouth, while the others fly away. In the same sly and brutal manner he snaps up dogs, horses, oxen, and even men who come to the river to drink.

One of the most dangerous ambushes which can be met on the road by animals who resort to a spring is that prepared by the Python. This gigantic snake hangs by his tail to the branch of a tree and lets himself droop down like a long creeper. The victim who comes within his reach is seized, enrolled, pounded in the knots which the snake forms around him. It is not necessary to multiply examples of this simple and widespread method of hunting.

Not content with utilising the natural arrangements they meet with, there are animals which construct genuine ambushes, acting thus like Man, who builds in the middle or on the edge of ponds, cabins in which to await wild ducks, or who digs in the path of a lion a hole covered with trunks of trees, at the bottom of which he may kill the beast without danger. Certain insects practise this method of hunting. The Fox, for instance, so skilful a hunter in many respects, constructs an ambush when hunting hares.[11]

[11] C. St. John, Wild Sports, etc., chap. xx.

The larva of the Tiger Beetle (Cicindela campestris) constructs a hole about the size of a feather quill, disposed vertically, and of a depth, enormous for its size, of forty centimetres. It maintains itself in this tube by arching its supple body along the walls at a height sufficient for the top of its head to be level with the surface of the soil, and to close the opening of the hole. (Fig. 1.) A little insect—an ant, a young beetle, or something similar—passes. As soon as it begins to walk on the head of the larva, the latter letting go its hold of the wall allows itself to fall to the bottom of the trap, dragging its victim with it. In this narrow prison it is easily able to obtain the mastery over its prey, and to suck out the liquid parts.[12]

[12] Lamarck, Histoire des Animaux sans Vertebres, 2e edition, 1835, p. 676.

The Staphilinus Caesareus acts with still greater shrewdness; not only is his pit more perfect, but he takes care to remove all traces of preceding repasts which might render the place obviously one of carnage. He chooses a stone, beneath which he hollows a cylindro-conical hole with extremely smooth walls. This hole is not to serve as a trap, that is to say that the proprietor has no intention of causing any pedestrian to roll to the bottom. It is simply a place of concealment in which he awaits the propitious moment. No creature is more patient than this insect, and no delay discourages him. As soon as some small animal approaches his hiding-place he throws himself on it impetuously, kills it, and devours it. Near his ditch he has hollowed a second of a much coarser character, the walls of which have not been smoothed with the same care. One here sees elytra and claws piled up; they are the hard and horny parts which he has not been able to eat. The heap in this ditch is not then an alimentary store. It is the oubliette in which the Staphilinus buries the remains of his victims. If he allowed them to accumulate around his hole all pedestrians would come to fear this spot and to avoid it. It would be like the dwelling of a Polypus, which is marked by the numerous carapaces of crabs and shells which strew the neighbourhood.

The ambuscade of the Ant-lion is classic; it does not differ greatly from the others. He excavates a conical pitfall, in which he conceals himself, and seizes the unfortunate ants and other insects whom ill-chance causes to roll into it.[13]

[13] See e.g. Tennent, Ceylon, vol. i. p. 252. Also Reaumur, Memoires pour d'histoire des Insectes, t. i. p. 14, and t. vi. p. 333.

The baited ambush.—A variety of ambush which brings this method of hunting to considerable perfection lies in inciting the prey to approach the hiding-place instead of trusting to chance to bring it there. In such circumstances Man places some allurement in the neighbourhood—that is to say, one of the foods preferred by the desired victim, or at least some object which recalls the form of that food, as, for example, an artificial fly to obtain possession of certain fishes.

It is curious to find that fish themselves utilise this system; it is the method adopted by the Angler and the Uranoscopus.[14] The Uranoscopus scaber lives in the Mediterranean. At the end of his lower jaw there is developed a mobile and supple filament which he is able to use with the greatest dexterity. Concealed in the mud, without moving and only allowing the end of his head to emerge, he agitates and vibrates his filament. The little fishes who prowl in the neighbourhood, delighted with the sight of this apparent worm, regarding it as a destined prey, throw themselves on to it, but before they are able to bite and recognise their error they have disappeared in the mouth of the proprietor of the bait.

[14] Lacepede, Histoire des Poissons, 1798-1803.

The Angler (Lophius piscatorius) has not usurped his rather paradoxical name. He retires to the midst of the sea-weed and algae. On his body and all round his head he bears fringed appendages which, by their resemblance to the leaves of marine plants, aid the animal to conceal himself. The colour of his body also does not contrast with neighbouring objects. From his head arise three movable filaments formed by three spines detached from the upper fin. He makes use of the anterior one, which is the longest and most supple. Working in the same way as the Uranoscopus, the Angler agitates his three filaments, giving them as much as possible the appearance of worms, and thus attracting the little fish on which he feeds.

In these two examples we see a special organ utilised for a particular function; it is one of the intermediate cases, already referred to, between the true industries involving ingenuity and the simple phenomena due to adaptations and modifications of the body.

Hunting in the dwelling or in the burrow.—All these methods of hunting or of fishing by surprise are for the most part practised by the less agile species which cannot obtain their prey by superior fleetness. Midway between these two methods may be placed that which consists in surprising game when some circumstance has rendered it motionless. Sometimes it is sleep which places it at the mercy of the hunter, whose art in this case consists in seeking out its dwelling. Sometimes he profits by the youth of the victim, like all bird-nesters, whose aim is to eat the eggs or to devour the young while still incapable of flying. The animals who eat birds' eggs are numerous both among mammals and reptiles, as well as among birds themselves.

The Alligator of Florida and of Louisiana delights in this chase. He seeks in particular the Great Boat-Tail (Quiscalus major) which nests in the reeds at the edge of marshes and ponds. When the young have come out and are expecting from their parents the food which the chances of the hunt may delay, they do not cease chirping and calling by their cries. But the parents are not alone in hearing these appeals. They may also strike the ears of the alligator, who furtively approaches the imprudent singers. With a sudden stroke of his tail he strikes the reeds and throws into the water one or more of the hungry young ones, who are then at his mercy. (Audubon.)

The animals who feed on species living in societies either seize on their prey when isolated or when all the members of the colony are united in their city. A search for the nest is necessary in the case of creatures who are very small in comparison with the hunter, as in the case of ants and the Ant-eater. But the ant-eater possesses a very long and sticky tongue, which renders the capture of these insects extremely easy; when he finds a frequented passage it is enough to stretch out his tongue; all the ants come of their own accord and place themselves on it, and when it is sufficiently charged he withdraws it and devours them. The African Orycteropus (Fig. 2), who is also a great eater of ants and especially of termites, is equally aided by a very developed tongue; but he has less patience than the ant-eater, and he adds to this resource other proceedings which render the hunt more fruitful and enable him to obtain a very large number of insects at one time. Thanks to his keenness of scent he soon discovers an ant-path bearing the special and characteristic odour which these Hymenoptera leave behind them, and he follows the track which leads to their nest. On arriving there, without troubling himself about the scattered insects that prowl in the neighbourhood, he sets himself to penetrate into the midst of the dwelling, and with his strong claws hollows out a passage which enables him to gain access. On the way he pierces walls, breaks down floors, gathering here and there some fugitives, and arrives at last at the centre, in which millions of animals swarm. He then swallows them in large mouthfuls and retires, leaving behind him a desert and a ruin in the spot before occupied by a veritable palace, full of prodigious activity.

The colonies are not only exposed to the devastations of those who feed on their members; they have other enemies in the animals who covet their stores of food. The most inveterate robber of bees is the nocturnal Death's Head Moth. When he has succeeded in penetrating the hive the stings of the proprietors who throw themselves on him do not trouble him, thanks to his thick fleece of long hairs which the sting cannot penetrate; he makes his way to the cells, rips them open, gorges himself with honey, and causes such havoc that in Switzerland, in certain years when these butterflies were abundant, numbers of hives have been found absolutely empty.[15] Many other marauders and of larger size, such as the Bear, also spread terror among these laborious insects and empty their barns. No animal is more crafty than the Raven, and the fabulist who wished to make him a dupe was obliged to oppose to him the very cunning Fox in order to render the tale fairly life-like. A great number of stories are told concerning the Raven's cleverness, and many of them are undoubtedly true. There is no bolder robber of nests. He swallows the eggs and eats the little ones of the species who cannot defend themselves against him; he even seeks the eggs of Sea-gulls on the coast; but in this case he must use cunning, for if he is discovered it means a serious battle. On the coast also the Raven seeks to obtain possession of the Hermit-crab. This Crustacean dwells in the empty shells of Gasteropods. At the least alarm he retires within this shell and becomes invisible, but the bird advances with so much precaution that he is often able to seize the crab before he has time to hide himself. If the raven fails he turns the shell over and over until the impatient crustacean allows a claw to emerge; he is then seized and immediately devoured.

[15] Huber, Nouvelles Observations sur les Abeilles, t. ii. p. 291.

If there is a question of hunting larger game like a Hare, the Raven prefers to take an ally. They start him at his burrow and pursue him flying. In spite of his proverbial rapidity the hare is scarcely able to flee more than two hundred yards. He succumbs beneath vigorous blows on his skull from the beaks of his assailants. During winter, in the high regions of the Alps, when the soil is covered with snow, this chase is particularly fruitful for ravens. The story is told of that unfortunate hare who had hollowed out in the snow a burrow with two entrances. Two of these birds having recognised his presence, one entered one hole in order to dislodge the hare, the other awaited him at the other opening to batter his head with blows from his beak and kill him before he had time to gain presence of mind.[16]

[16] F. von Tschuedi, Les Alpes, Berne and Paris, 1859.

Rooks sometimes hunt in burrows by ingeniously-concerted operations. Mr. Bernard[17] has described the interesting way in which the Rook hunts voles or field-mice in Thuringia. His curiosity was excited by the way in which numerous rooks stood about a field cawing loudly. In a few days this was explained: the field was covered with rooks; the original assemblage had been calling together a mouse-hunt, which could only be successfully carried out by a large number of birds acting in conjunction. By diligently probing the ground and blocking up the network of runs, the voles, one or more at a time, were gradually driven into a corner. The hunt was very successful, and no more voles were seen in that field during the winter.

[17] Zoologist, October 1892.

Coursing.—Other animals are not easily discouraged by the swiftness of their prey; they count on their own resistance in order to tire the game; some of them also manage their pursuit in the most intelligent way, so as to preserve their own strength while the tracked animal's strength goes on diminishing until exhaustion and fatigue place him at their mercy.

Mammals especially, such as Dogs, Wolves, and Foxes, exercise this kind of chase; it is, exactly, the coursing which Man has merely had to direct for his own benefit. Wild dogs pursue their prey united in immense packs. They excite each other by barking while they frighten the game and half paralyse his efforts. No animal is agile and strong enough to be sure of escaping. They surround him and cut off his retreat in a most skilful manner; Gazelles and Antelopes, in spite of their extreme nimbleness and speed, are caught at last; Boars are rapidly driven into a corner; their vigorous defence may cost the life of some of the assailants, but they nevertheless become the prey of the band who rush on to the quarry. In Asia wild dogs do not fear even to attack the tiger. Many no doubt are crushed by a blow of the animal's paw or strangled in his jaws, but the death of comrades does not destroy either the courage or the greediness of the surviving aggressors. Their number also is such that the great beast, covered by agile enemies who cling to him and wound him in every part, must at last succumb.

Wolves hunt also in considerable bands. Their audacity, especially when pressed by hunger in the bad season, is well known. In time of war they follow armies, to attack stragglers and to devour the dead. In Siberia they pursue sledges on the snow with terrible perseverance, and the pack is not delayed by the massacre of those who are shot. A few stop to devour at once their fallen comrades, while the others continue the pursuit.

Besides these brutal chases wolves seem able to exercise a genuine feint. Sometimes it is a couple who hunt in concert. If they meet a flock, as they are well aware that the dog will bravely defend the animals entrusted to him, that he is vigilant, and that his keen scent will bring him on them much sooner than the shepherd, it is with him that they first occupy themselves. The two wolves approach secretly; then suddenly one of them unmasks and attracts the attention of the dog, who rushes after him with such ardour that he fails to perceive that in the meantime the second thief has seized the sheep and dragged it into the wood. The dog finally renounces his pursuit of the fugitive and returns to his flock. Then the two confederates join each other and share the prey. In other circumstances it is a wolf who hunts with his female. When they wish to obtain possession of a deer, whose robust flight may last a long time, one of the couple, the male for example, pursues him and directs his chase in such a way that the game must pass by a place where the female wolf is concealed. She then takes up the chase while the male reposes. It is an organised system of relays. The strength of the deer becomes necessarily exhausted; he cannot resist the animation shown by his active foe, and is seized and killed. Then the other wolf calmly approaches the place of the feast to share his part of the booty.

The small but bold Hawk called the Merlin also courses in relays in exactly the same manner. These birds pursue a Lark or a Swallow in the most systematic manner. First one Merlin chases the bird for a short time, while his companion hovers quietly at hand; then the latter relieves his fellow-hunter, who rests in his turn. The victim is soon tired out and caught in mid-air by one of the Merlins, who flies away with him, leaving his companion to hunt alone, while he feeds the young brood.[18]

[18] C. St. John, Wild Sports and Natural History of the Highlands, chap. xi.

The Fox also successfully uses this method of coursing with relays. There are indeed few animals who possess so many tricks of all kinds to gain possession of their prey. Constantly prowling about the fields, he neglects no propitious circumstance, and profits by all the advantages furnished by the situation of places or the habits of the game he is seeking. He pursues tired or wounded animals whom he meets, and easily masters them. If he finds a burrow, he quickly hollows a hole and brings to light the young rabbits who thought themselves in safety in the bowels of the earth; he robs nests placed in the thickets, and devours the young birds. Beehives are not protected against his greediness by the stings of the swarms; he rolls on the earth, crushes his assailants, and finally triumphs over the discouraged insects and gorges himself with honey.

Birds of prey also invent ingenious combinations to reach a good flier. Most of the great rapacious birds of rapid flight or with powerful talons are so well organised for the chase that they have no need of cunning. To see the prey, to seize it and devour it, are acts accomplished in a moment by the single fact of their natural organisation. It is rather among those who are less well endowed that one finds real art and frequent ruses. The Goshawk (Astur palumbarius, Fig. 3) is sufficiently strong and flies sufficiently well to seize small birds; but in order to obtain a copious repast at one snatch he prefers to attack pigeons. Generally the strength of their wings promptly places them in safety. He therefore hides himself in the neighbourhood of the pigeon-house, ready to fall on those pigeons who pick up food around. But the pigeons are suspicious, and if they recognise his presence they remain hidden in their dwellings. In this case it has sometimes been found that the Goshawk has quietly flown up to their house and alighted on its summit; there, by violently beating his wings, he gives a succession of sudden blows to the roof. Startled and frightened by this unaccustomed noise, the inhabitants dart out, and the bird of prey can then profit by their alarm to seize one or two.[19]

[19] Wodzicki, "Ornithologische Miscell.," Journ. f. Ornithol., 1856.

The Pseudaetus is also obliged to have recourse to a subterfuge in order to gain birds that fly well. He easily destroys fowls, and hunts them so successfully that in Spain, in certain isolated farms, it has been necessary to give up rearing fowls in consequence of these numerous depredations. But to seize pigeons is not so easy a matter. Generally, according to Jerdon, two birds unite to attack a band. One of the aggressors pretends to wish to seize them from below. This is a very unusual method, for birds of prey always rise above the game in order to throw themselves down on it. This puts out the pigeons, and they fear the manoeuvre all the more because they are unaccustomed to it. During this instant of confusion the second assailant passes unperceived above them, plunges into the midst and seizes a pigeon; there is a new panic, by which the first aggressor profits in order to rise rapidly in his turn and seize a second victim.

Struggles that terminate the hunt.—It is not always sufficient for the hunter to find game and to reach it. If the game is of large size it may be able to hold its own, and the pursuit may end in a violent struggle, in which both skill and cunning are necessary to obtain conquest.

The Bald Eagle of North America (Haliaeetus leucocephalus) hides himself on a rock by the edge of a stream and awaits the passing of a swan. This eagle is brave and strong, but the palmiped is vigorous, and though inferior in the air, he has an advantage on the water, and may escape death by plunging. The eagle knows this advantage, so he compels the swan to remain in the air by attacking him from below and repeatedly striking his belly. Weakened by the flow of blood, and obliged to fly, not being able to reach the water without finding the sharp beak which strikes him, the swan succumbs in this unequal combat, which has been vividly described by Audubon.

The bird who displays the most remarkable qualities in this struggle which terminates the chase, exhibiting indeed a real fencing match, is the Secretary Bird (Gypogeranus reptilivorus. Fig. 4.) He is the more interested in striking without being himself struck since the fangs with which his prey, the snake, is generally armed might at the first blow give him a mortal wound. In South Africa he pursues every snake, even the most venomous. Warned by instinct of the terrible enemy he has met, the reptile at first seeks safety in flight; the Secretary follows him on foot, and the ardour of the chase does not prevent him from being constantly on guard. This is because the snake, finding himself nearly overtaken, suddenly turns round, ready to use his defensive weapons. The bird stops, and turns in one of his wings to protect the lower parts of his body. A real duel then begins. The snake throws himself on his enemy, who at each stroke parries with the end of his wing; the fangs are buried in the great feathers which terminate it, and there leave their poison without producing any effect. All this time with the other wing the Secretary repeatedly strikes the reptile, who is at last stunned, and rolls over on the earth. The conqueror rapidly thrusts his beak into his skull, throws his victim into the air, and swallows him.[20]

[20] The combat was minutely described by Le Vaillant (Hist. Nat. des Oiseaux d'Afrique, Paris, 1798, t. i. p. 177), whose account has been confirmed by many subsequent observers.

Hunting with projectiles.—It has often been repeated that Man is the only creature sufficiently intelligent to utilise as weapons exterior objects like a stone or a stick; in a much greater degree, therefore, it was said, was he the only creature capable of striking from afar with a projectile. Nevertheless creatures so inferior as fish exhibit extreme skill in the art of reaching their prey at a distance. Several act in this way. There is first the Toxotes jaculator, who lives in the rivers of India. His principal food is formed by the insects who wander over the leaves of aquatic plants. To wait until they fell into the water would naturally result in but meagre fare. To leap at them with one bound is difficult, not to mention that the noise would cause them to flee. The Toxotes knows a better trick than that. He draws in some drops of water, and, contracting his mouth, projects them with so much force and certainty that they rarely fail to reach the chosen aim, and to bring into the water all the insects he desires.[21] (Fig. 5.) Other animals also squirt various liquids, sometimes in attack, but more especially in defence. The Cephalopods, for example, emit their ink, which darkens the water and allows them to flee. Certain insects exude bitter or foetid liquids; but in all these cases, and in others that are similar, the animal finds in his own organism a secretion which happens to be more or less useful to his conservation. The method of the Toxotes is different. It is a foreign body which he takes up, and it is an intended victim at which he takes aim and which he strikes; his movements are admirably co-ordinated to obtain a precise effect.

[21] Cuvier et Valenciennes, Hist. Nat. des Poissons, Paris, 1831, t. vii. p. 231.

Another fish, the Chelinous of Java, also acts in this manner. He generally lives in estuaries. It is therefore a brackish water which he takes up and projects by closing his gills and contracting his mouth; he can thus strike a fly at a distance of several feet. Usually he aims sufficiently well to strike it at the first blow, but sometimes he fails. Then he begins again until he has succeeded, which shows that his movements are not those of a machine. He knows what he is doing, what effect ought to be produced, and whether this desired result has happened, and he perseveres until the insect has fallen. These facts are unquestioned; the Chinese preserve these curious fish in jars, and amuse themselves by making them carry on this little exercise. Many observers have witnessed and described it.

Particular circumstances put to profit.—In the various kinds of hunting which we have been passing in review, it is certain that the animals in question generally exercise them nearly always in the same manner. If an animal has carried out a ruse successfully he does not abandon it, but reproduces it as often as it is efficacious. When, however, conditions happen to change, animals are prompt to profit by them, and one sees how all these acts are derived from reflection. This is the clearer the more the favourable circumstance is accidental and unforeseen, when it is not possible to consider the animals as accustomed to profit by it.

In the wild regions of Africa it happens that from some reason or another, perhaps from the effect of lightning on immense forests, dense thickets or plains covered by tall plants become the prey of gigantic fires which spread as long as they find food on their road. The heat as of a furnace arises above and around; an acrid smoke veils everything, and the frightened animals flee before the scourge. Travellers who have witnessed these magnificent scenes often insist on the panics thus produced, and describe the inoffensive lion fleeing in the midst of a herd of gazelles. All are seized by the same fear, because all are exposed to the same danger. But birds, whose wings can carry them at will afar from the furnace, preserve greater presence of mind, and profit by the public calamity and general anxiety to make a successful hunt and copious feasts. One may see the birds of prey flying in front of the fire and seizing easy victims. Certain birds of Africa are the most furious hunters during a fire. Legions of insects flee far from the tall dried plants, and clouds of birds arrive to throw themselves on them. They pursue them with incredible audacity through the smoke close to the flames and always retire in time to avoid singeing. A member of the Crow family who inhabits India, Anomalocorax splendens, enjoys a deserved reputation of astuteness and allows no opportunity to escape without seizing it by the forelock. In ordinary times his food is composed of very varied substances—crabs, insects, worms, etc.; but if he perceives afar an ascending cloud he immediately abandons his small researches, knowing there is something better to be done over there. He is not selfish, and he calls a few comrades and they all put themselves into position to await events. They know very well the relation that exists between this smoke and the prey they covet. The fire indicated by the smoke can have no other reason in this hot country than the cooking of food. A Hindoo family are in fact installed and preparing their repast. The birds see all this and observe. The Hindoos are accustomed to throw outside the remains of their meals, and the Anomalocorax, who have come together from afar to await patiently this result, then throw themselves on the quarry. (Jerdon.)

Tennent narrates a singular trick which was twice, to his knowledge, played on a dog by two of these small glossy crows of Ceylon. The dog was gnawing a bone and would not be disturbed from the pure delight of sucking the marrow of which he was the legitimate proprietor. A crow approached the scene of the feast, and conceived the design of taking possession of it; he began by hopping around the dog, going and coming, trying to attract the animal's attention and ready to profit by the first distraction. His gambols remaining without result, he understood that he would not succeed and he flew away; but it was only to return accompanied by a friend possessing as little respect as himself for the property of others. The associate perched on a branch a few steps away, while the first crow renewed his attempts by flying around the bone and the dog; but the latter remained impassive. Then the second personage, whose part had hitherto been to remain contemplative, flew off his branch, threw himself on the dog and gave him a formidable blow on the spine. Seized with indignation, the dog turned round to punish the author of this unjustifiable aggression; but the bird was already far away, and in the meanwhile from the other side the first Anomalocorax seized the long-coveted bone and also took flight. The feelings of the sheepish dog who saw both his vengeance and his repast flying away in the air may be better imagined than described.[22]

[22] Tennent, Ceylon, vol. i. p. 171.

All the birds, indeed, of this family know how to reach their ends. I have already spoken of certain hunts of the Raven; it is even said that in Iceland he knows when a ewe is going to give birth to young, and awaits this moment with immense patience. As soon as the lamb appears the Raven alights on him, digs out his eyes, and devours them.

The Quelelis or Guadaloupe Caracara (Polyborus lutosus), a Californian bird of prey, is a cruel enemy to animals like the goat when they are about to bring forth their young. No sooner is one kid born, and while the mother is yet in labour with the second, than the birds pounce upon it, and should the mother be able to interfere, she is assaulted also. If there are a number of young kids together, the birds unite their forces and with great noise and flapping of wings succeed in separating the weakest and killing it.[23]

[23] Bendire, Life Histories of North American Birds, 1892, p. 319.

Dr. J. Lowe has recently called attention to a very curious method of attracting prey adopted by the Blackcap (Sylvia atricapilla) at Orotava, Teneriffe.[24] This bird has discovered that the juice exuded by certain flowers (Hibiscus Rosa sinensis and Abutilon frondosum) is attractive to the insects upon which he preys; he therefore punctures the petals of these flowers in order to promote the exudation of this viscid secretion.

[24] Linnaean Society, 1st June 1893.

Many of us in our schooldays have admired the intelligence of Jackdaws having their nests in some old tower or belfry. They are able to distinguish according to the hour the significance of the various school bells. Most of these clangs do not move them, and they continue to attend to their affairs without paying attention. Their attention is only attracted by the ringing which marks the beginning and the end of recreation time. At the sound of the first they all flee and abandon the courts before even a single pupil has yet appeared. The bell, on the contrary, which marks the end of recreation time invites them to descend in a band to collect the crumbs of lunch. They arrive in a hurry, so as to be the first to profit by the repast, not waiting even until the place is abandoned; they know very well that the young people still there are not to be feared, having no time now to be occupied with them.

In this class of facts, there are a certain number which may be considered as more marked by custom and perhaps less marked by spontaneous reflection. Such, for example, is the custom of Sharks and Seagulls to follow ships.

In the seas where Dog-fish are abundant, one or more of them become attached to a ship, and quit it neither night nor day. One may believe sometimes that they are not there; but if any object is thrown into the sea, the fin of one of these monsters appears at the surface; everything which is thrown overboard disappears in their large jaws—kitchen refuse, bottles, etc. When a dead body is thrown into the sea it is soon seized by the shark, while living men who fall into the water have great difficulty in escaping, and are often drawn up horribly mutilated and half dead.

Sea-gulls also follow vessels when they approach the coast. It is a pleasant sight to see the noisy band animating the monotonous splendour of the ocean; they arrive as soon as a vessel is one or two days' journey from land. Henceforth they do not leave her, flying behind and plunging in her wake; they profit by the disturbance produced by the gigantic machine to capture the stunned fishes.

On land exactly the same kind of chase is carried on by Rooks, Crows, and Magpies, who follow the plough to seize the worms which the ploughshare turns up in the open earth. In autumn they cover the fields, animated and active, pilfering as the furrow is hollowed out.

Certain rapacious birds who are awkward in hunting, especially Kites, make up for their lack of skill by audacious impudence. Constantly on the watch for better hunters like the Falcon, they throw themselves on him as soon as he has seized his prey. The proud bird, though much more courageous, stronger, and more skilful than these thieves, usually abandons the prey either because the burden embarrasses him in the struggle, or else because he knows that he can easily find another. These highway robbers of the air often unite to gain possession of a prey already taken and killed, and ready to be eaten. A handsome Falcon of the Southern States of North America, the Caracara Eagle (Polyborus cheriway), frequently steals fish from the Brown Pelicans on the coast of Texas. When the Pelicans are returning from their expeditions with pouches filled with fish, the Caracaras attack them until they disgorge, and then alight to devour the stolen prey. They do not attack the outgoing birds, but only the incoming ones, and they wait until they reach the land (so that the contents of the pouches may not fall into the water) before pouncing on them.[25]

[25] Bendire, Life Histories of North American Birds, p. 315.

Among other animals a habit has been formed from some special circumstance. As an extreme case in this group we meet with parasites of whom some cannot live outside a particular nest, and are even absolutely transformed by this kind of life. But between these and independent hunters there are an extreme number of intermediate stages, of which it is sufficient to mention a few.[26]

[26] For a discussion of this subject, see P. van Beneden, Commensaux et Parasites, Paris, 1875.

The Fierasfer, a little fish of the Mediterranean, installs himself in the respiratory cavity of a Holothurian; he does not live at the expense of his host's flesh, but contents himself with levying a tax on the foods which enter the cavity. It is a case of commensalism of which there are very numerous examples. Other cases may be mentioned which are still further removed from parasitism. Among these may be mentioned the birds who relieve large mammals of their vermin.

One of them, the Red-beaked Buffalo bird (Buphaga erythrorhyncha), lives in Abyssinia. This bird is insectivorous. He has remarked that the ruminants constitute baits for flies; therefore he never leaves these animals, hops about on their backs and delivers them from annoying parasites; the buffaloes, who recognise this service, allow the bird to wander quietly over their hide. The Buphaga, who gives himself up entirely to this kind of chase, is often called the Beef-eater. He is only found in the society of flocks, of camels, buffaloes, or oxen. He settles on the back, legs, and snouts of these living baits. They remain passive even when he opens the skin in order to draw out the flies' larva; they know the benefit of this little operation. The patience of the oxen is certainly due to custom, for it is observed that herds which are not used to this bird manifest great terror when he prepares to alight on them, so that they even take flight from this small aggressor.

Sometimes it is not easy to understand the advantages derived by the animal from the conditions in which he is usually found. Thus, for example, there is a fish, the Polyprion cernium, which accompanies driftwood on which Barnacles have fixed themselves. Yet the remains of these Crustaceans are never found in his stomach, and it is known on the contrary that he lives exclusively on other small fish. It is possible that these find their food in fragments of wood at the expense of the barnacles, and that therefore the Polyprion which hunts them is always near driftwood thus garnished.

Methods of utilising the captured game.—Frequently it is not enough for the animal to obtain possession of his prey. Before making his meal it is still necessary to find a method of making use of it, either because the eatable parts are buried in a thick shell which he is unable to break, or because he has captured a creature which rolls itself into a ball and bristles its plumes. Here are some of the more curious practices followed in such cases.

Sometimes it is a question of carrying off a round fruit which offers no prominence to take hold of. The Red-headed Melanerpes (Melanerpes erythrocephalus) of North America is very greedy with regard to apples, and feeds on them as well as on cherries. It takes him a considerable time to consume an apple, and as he is well aware of the danger he runs by prolonging his stay in an orchard, he wishes to carry away his booty to a safe and sheltered spot. He vigorously plunges his open beak into the apple; the two mandibles enter separately, and the fruit is well fixed; he detaches it and flies away to the chosen retreat. Apes are very skilful in utilising their booty. Cocoa-nuts are rather hard to open, but Apes do not lose any part of them; they first tear off the fibrous envelope with their teeth, then they enlarge the natural holes with their fingers, and drink the milk. Finally, in order to reach the kernel they strike the nut on some hard object exactly as Man would do. The Baboons (Cynocephali), whose courage is prodigious, since they will fight in a band against a pack of dogs or even against a leopard, are also very prudent and very skilful. They know that courage is no use against the sting of a venomous snake, and that the best thing is to avoid being bitten. The scorpion, whose dart is perfidious, also inspires their distrust, but as they like eating him they endeavour to catch him. This is not indeed very difficult if one carefully observes his movements, and it is possible to seize him suddenly by the tail, as I have often done, without being stung. Apes employ this method, pull out his sting, and crunch the now inoffensive Arachnid. They also like ants, but fear being bitten by them; when they wish to enjoy them, they place an open hand on an ant-hill and remain motionless until it is covered by insects. They can then absorb them at one stroke without fear.

One would not think that an animal so well defended as the Hedgehog need fear becoming the prey of the Fox. Rolled in a ball, bristling with hard prickles which cruelly wound an assailant's mouth, nothing will induce him to unroll so long as he supposes the enemy still in the neighbourhood. It is vain to strike him or to rub him on the earth; he remains on the armed defensive. Only one circumstance disturbs him to the point of making him quit his prudent posture; it is to feel himself in the water, or even simply to be moist. The fox is acquainted with this weakness, therefore as soon as he has captured a hedgehog he rolls him in the nearest marsh to strangle him as soon as his head appears. It may happen that there is no puddle in the neighbourhood suitable for this bath; it is said that in this case the fox is not embarrassed for so small a matter, and provides from his own body the wherewithal to moisten the hedgehog.

The combination is complicated, and approaches more nearly the methods employed by Man when the animal makes use of a foreign body, as a tool or as a fulcrum, to achieve his objects. A snake is very embarrassed when he has swallowed an entire egg with the shell; he cannot digest it in that condition, and the muscles of his stomach are not strong enough to break it. The snake often finds himself in this condition, and is then accustomed either to strike his body against hard objects or to coil himself around them until he has broken the envelope of the eggs he contains.

The Snake himself is treated in this way in South America. The Sulphur Tyrant-bird picks up a young snake by the tail, and, flying to a branch or stone, uses it like a flail until its life is battered out.[27]

[27] W. H. Hudson, Naturalist in La Plata, p. 73.

It would be a paradox to attribute great intelligence to Batrachians; yet certain facts are recorded which show them to be capable of reflection. Among others the case is quoted of a green frog who obtained possession of a small red frog, and who proposed to swallow him. The other was naturally opposed to the realisation of this scheme and struggled with energy. Seeing that he would not succeed, the green frog went towards the trunk of a tree and, still holding his victim, struck him many times vigorously against it. At last the red frog was stunned, and could then be swallowed at leisure.

Gasteropods are not always protected by their calcareous shells any more than tortoises are by their carapaces; for certain birds know very well how to break them. Ravens drop snails from a height, and thus get possession of the contents of the shell.

The most celebrated breaker of shells is the Bearded Vulture or Lammergeyer (Gypaeetos barbatus). This rapacious bird is very common in Greece, where he does not usually live on large prey. If he sometimes carries away a fowl, it is exceptional; he prefers to live on carrion or bones, the remains of the feasts of man or of the true vulture. He rises very high carrying these bones in his talons and allows them to fall on a stone, swallowing the fragments after having sucked out the marrow. He is also greedy of tortoises, and uses the same method to break their carapaces, eating the soft parts. These facts have been many times observed by Brehm and other trustworthy naturalists. It is even said that in Greece every Lammergeyer chooses a rock on which he always comes to execute the tortoises he has captured. It was no doubt beneath one of these birds so occupied that, according to the story, mischance conducted AEschylus.

Neither the beak nor the claws of the Shrike or Butcher-bird (Lanius excubitor) are strong enough to enable him to tear his prey easily. When he is not too driven by hunger he installs himself in a comfortable fashion for this carving process, places on a thorn or on a pointed branch the victim he has made, and when it is thus fixed easily devours it in threads.

The Lanius collurio, an allied bird, uses this method still more frequently. He even prepares a small larder before feasting. One may thus see on a thorny branch spitted side by side Coleoptera, crickets, grasshoppers, frogs, and even young birds, which he has seized when they were in flight.[28] (Fig. 6.)

[28] Naumann, Naturgeschichte der Voegel Deutschlands, etc., Stuttgart, 1846-53.

Of all these well-attested facts that which perhaps best shows how animals in certain circumstances may take advantage of a foreign body to utilise the product of the chase, is the following, the observation of which is due to Parseval-Deschenes.[29] He followed during several hours an ant bearing a heavy burden. On arriving at the foot of a little hillock the animal was unable to mount with his load, and abandoned it—a very extraordinary fact for one who knows the inconceivable tenacity of insects. The abandonment therefore left hope of return. The ant at last met one of his companions, who was also carrying a burden. They stopped, took counsel for an instant, bringing their antennae together, and started for the hillock. The second ant then left his burden, and both together then seized a twig and introduced its end beneath the first load which had been abandoned because of its weight. By acting on the free extremity of the twig they were able to use it exactly as a lever, and succeeded almost without trouble in passing their booty on to the other side of the little hillock. It seems to me that these ants who invented the lever are worthy of admiration, and that their ingenuity does not yield to our own.

[29] Gratien de Semur, Traite des erreurs et des prejuges, Paris, 1848, p. 70.

I will, finally, give an example of the methods of surmounting a difficulty of another order in utilising captured prey. It is not enough to capture prey, or even to possess the means of utilising the prey when captured. It is sometimes also necessary to prevent the booty being taken possession of by some other member of the same species as the hunter. Spiders are specially liable to this danger, because their victims are noisy when caught. Hudson has described an ingenious device made use of by a species of Pholcus—a quiet inoffensive Spider found in Buenos Ayres—to escape this risk. This spider, though large, is a weak creature, and possesses little venom to despatch a fly quickly. The task of killing it is therefore long and laborious, and the loud outcries of the victim may be heard for a long time, sometimes for ten or twelve minutes. The other spiders in the vicinity are naturally excited by this noise, and hurry out from their webs to the scene of conflict, and the strongest or most daring sometimes succeeds in carrying away the fly from its rightful captor. Where, however, a large colony have been long in undisturbed possession of a ceiling, when one has caught a fly he rapidly throws a covering of web over it, cuts it away, and drops it down to hang suspended by a line at a distance of two or three feet from the ceiling. The other spiders arrive on the scene, but not finding the cause of the disturbance retire to their own webs again. When the coast is thus clear, our spider proceeds to draw up the captive fly, now exhausted by its struggles.[30]

[30] W. H. Hudson, Naturalist in La Plata, 1892, p. 189.

War and brigandage.—When Man attacks animals of another species, either to kill them and feed on their flesh, or to steal the provisions which they have amassed for themselves or their young, this is called "hunting," and is considered as perfectly legitimate. When men turn to beings of their own species either to kill them or to rob them, several different cases are distinguished. If the assailants are few in number, it is called "brigandage," and is altogether reprehensible; but if both assailant and assailed are considerable in number, the action is called "war," and receives no reprobation.

There are hunters among animals as well as among ourselves, and we have seen their various methods of procedure; but there are also brigands and warriors, and our superiority even in this department is not so absolute as might be imagined.

Independently of ordinary brigandage, which is a brutal and simple form of the struggle for life, manifested every time the animals find themselves before a single repast, there are interesting facts to be noted concerning robbers who act in a manner that Man himself would not disavow. It is worthy of remark that it is the most sociable animals who furnish us with the most characteristic examples.

Bees have a just renown as honest and laborious insects; there are, however, some who depart from the right road, and they do not do it by halves.[31] Among Hymenoptera the lazy profess the theory that pollen belongs to all bees, and that stored-up honey does not constitute private property. Therefore, to protest against work and economy, sly methods are employed by a few to utilise as their own private property the resources which Nature has made for all; they adopt the plan of plundering the working insects, and carrying away for themselves the pollen which the others had had the audacity to seek among the flowers.

[31] L. Buechner, Aus d. Geistesleben d. Thiere, Berlin, 1879.

To arrive at these ends these clever Hymenoptera employ cunning, and endeavour to pose as workers. They place themselves at the approaches to a hive, and when a worker arrives laden with its burden they advance towards it, caress it with their antennae, take possession of its pollen as if to relieve it of a burden, and then fly away to their own hive.

Others adopt less diplomatic proceedings. Some unite to intrude in a badly-guarded hive, and gorge themselves with the honey to which they have no right. Following up this success, they bring accomplices; a veritable band of brigands is organised, who have no other industry than to seize honey already manufactured in order to fill their own cells. Their audacious enterprises are not always crowned with success; they are repulsed in populous and well-organised hives, but they are successful in the weaker ones. Sometimes they act with violence, and to reduce a swarm they first fall on the queen and kill her with their stings. Disconcerted by her death, the bees allow the pillage of their dwelling, and the cells are robbed from top to bottom. In some cases the deprived proprietors, in their turn carried away by this insanity of rapine, even go over themselves to the assailing party, and carry their own honey to the house of the bandits. Henceforth they unite their fortune to that of the others, and share in their easy and adventurous life.[32]

[32] P. Huber, Recherches sur les Moeurs des Fourmis indigenes, Paris and Geneve, 1810, chap. ix.

Bates has given a vivid description of the armies of the South American Foraging Ants (Eciton). They are carnivorous hunters who march in large armies, and are found on the banks of the Amazon, especially in the open campos of Santarem. The Eciton legionis chiefly carry off the mangled larvae and pupae of other ants. They will attack the nests of a bulky species of the genus Formica; they lift out the bodies of these ants and tear them in pieces, as they are too large for a single Eciton to carry off, a number of carriers seizing each fragment. They seem to divide into parties, one party excavating and the other carrying away the grains of earth to a distance from the hole just sufficient to prevent them rolling back into it. There is, however, no rigid distribution of labour, the miners sometimes becoming carriers, and then again assuming the office of carrying off the prey. In marching off they form a broad and compact column, sixty or seventy yards in length, those who may be empty-handed assisting heavily-laden comrades. The Eciton drepanophora attacks and carries off all kinds of insects, especially wingless species, such as maggots, caterpillars, larvae of cockroaches, etc. An eyeless species,[33] the Eciton erratica, rapidly forms covered passages under which to advance, and shows great skill in fitting the keystone to these convex arcades.[34]

[33] Belt points out that blindness is an advantage in the particular mode of hunting adopted by these ants, enabling them to keep together. Those species of Eciton which hunt singly have very well developed eyes.

[34] Bates, Naturalist on the Amazons (edition of 1892), pp. 355-363.

Belt has also made some extremely interesting observations on the Ecitons, whom for intelligence he places first among the ants of Central America, and as such at the head of the Articulata.[35]

[35] See Naturalist in Nicaragua, 1888, pp. 17-29.

Expeditions to acquire slaves.—In order to reduce one's own species to slavery, it seems at first that an intelligence is required as developed as that of Man. It is necessary in fact to attack beings nearly equally well endowed from an intellectual and physical point of view. The enterprise evidently presents every possible difficulty; but in case of success, the result more than compensates for the effort. The master in future need not trouble to work, for he possesses a tool capable of doing everything as well as himself, since by means of language he can easily impress his will on the acts of the other; a domestic animal is only an auxiliary, the slave entirely replaces his owner in every labour.

Several species of ants thus obtain slaves. The best known of these is the Polyergus rufescens. We shall see in another chapter in what way they take advantage of slaves, and what relations they have with them. At present it is only necessary to say how the slaves are obtained. The expeditions organised for this purpose are simply a perfected chase, both by the way in which they are conducted, and by the result to which they are to lead. It is not a question of brutally seizing a prey to be devoured immediately. The captured animal must be carefully managed, carried away alive and in such a condition that it has not yet known a free life, and can accustom itself to new conditions. When the Polyergus or Amazon ants desire to increase their band of slaves, one first remarks extreme excitement in the neighbourhood of the nest. They all come out helter-skelter, but this disorder lasts only for a short time; they soon form in line, and a regular serried column is formed, longer or shorter according to the swarm; it has been found to measure more than five metres long by fifteen centimetres broad. The Amazons advance, often changing their direction like a dog who is seeking a scent: this is exactly what they are doing, they smell the ground with their antennae in order to recognise traces of the Formica fusca. In this march the eminently republican instinct of the ants comes out. The band has no chief; those who are at the head go forward smelling the ground; this slackens their pace, so that they are passed by those in the ranks behind. Little by little they fall into single file, and this continuing during the whole course of the march, a particular ant may sometimes be at the head of the column, sometimes in the middle, sometimes in the rear. At the end of a longer or shorter period the expedition discovers a scent, which it follows up to the nest of the Formica fusca. The alarm is immediately given in the threatened ant-hill; the approach is announced of a band of slavers, and they all rush out, some to face their terrible adversaries while the others take up the nymphs and eggs in their mandibles and flee in all directions to save as many as possible of their offspring. The small ants endeavour with their burdens to climb to the summits of blades of grass; those who succeed are in safety with the eggs that they carry, for the Amazons do not climb. In the meanwhile a fierce battle is going on in the neighbourhood of the nest between the Formica fusca, who have made a sortie, and the slavers. It is an unequal struggle, because the latter are armed with formidable jaws, strong and sharp, borne by a large head with powerful muscles. The defenders of the nest are seized and placed hors de combat. They flee discouraged, and the assailants force the entry of the dwelling. They then take possession of the larvae and nymphs and come out again holding them in their mandibles. The Polyergus thus laden flee as fast as possible, escaping as well as they can from the bereaved parents, who endeavour to save their offspring. The band returns to the nest by the same road that it came, although not the shortest, for these insects seem to lack the sense of direction and are guided by smell, so that they have to retrace all the windings of the road. The march is slackened by the weight of the booty (Fig. 7), and each travels according to his fancy, without following the regular order of the departure. At last the ants regain their household. The slaves, warned of the return of the victorious army, rush out to meet it and relieve the arrivals of their burdens, some in their zeal even carrying at the same time both the master and his burden. The nymphs transported into the ant-hill are henceforth cared for by their fellow-slaves; the Polyergus do not trouble themselves further.

Wars of the ants.—As sociable as man, the manners of ants present more than one resemblance to his. Slave-hunting expeditions are among these; the wars that these insects undertake also resemble human wars. The causes of the quarrel are of various nature, most often they result from the close proximity of two ant swarms. The rival colonies are always meeting in the same regions and seeking the same material; their mutual rivalry strains their relations. A moment comes when one of them is decidedly in the way of the other. At such a period, which is almost a diplomatic crisis, great excitement is observed in the two camps; there is a continual coming and going. One fine day, as the result of some unknown act,—some mysterious casus belli or declaration of war,—two armies place themselves on the march against each other. They advance in serried ranks. All ants do not follow the same tactics; some throw themselves out in a thicker line, while others form in squares. But as soon as action commences the individual regains his rights. It is a series of duels, of fierce hand-to-hand struggles. Legs are torn away, heads are cut off by strokes of the jaws, abdomens are disembowelled; a terrible fury animates the combatants, and nothing will disturb them from the battle. (Fig. 8.) By-and-by victory remains with the fiercest or the strongest; the vanquished draw in, carrying away as far as possible their wounded and their dead. Nothing more is seen on the field of carnage but separated limbs or heads which strew the ground like a multitude of small black points. Often the enmity is not extinguished after a battle, and several defeats are necessary before the weaker swarm is destroyed or forced to emigrate.[36]

[36] P. Huber, Moeurs des Fourmis indigenes, chap. ix. Many of the chief observations—given in the words of the original observers—as well as a summary of the facts known regarding the social activities of ants generally, will be found in the useful volume by Romanes in the International Scientific Series, Animal Intelligence, 1882.




Studying the animal kingdom in the manner here adopted, that is to say by passing in review the various manifestations of zoological life, we are necessarily led to find certain industries which are opposed to others. We have seen the various methods of hunting; but attack calls forth defence. In the struggle for life we find the action of beings on other beings, and the re-action of these latter; the final result is the expression of the difference between the two according as one or the other is stronger.

Flight.—Just as the most rudimentary method of attack is simple pursuit, so the most simple and natural method of defence is flight; but if very fleet animals like hares, gazelles, and deer can escape by simply exerting their maximum rapidity, it is not always thus, and certain species exercise in flight perfected methods appropriate to circumstances, and so raise this method of defence to an art.

Of all animals the Ape most skilfully directs his flight. There is no question that in his intelligence we may find every rudiment of our own; but of all his qualities none more nearly approximates him to us than his courage. There are no animals, not even the great beasts of prey, who are so brave as Man and the Ape, and who are capable of so much presence of mind. It is perhaps this bravery which, joined to his sociability, has most contributed to assure the supremacy of the one. As to the other, the road has been barred to him by his better-endowed cousin; he is disappearing before Man, and not before nature or other animals. In thinly-inhabited regions he is still the king. It is generally considered that the Lion is the incarnation of courage, but he is the strongest and the best armed; there is none before whom he need tremble. In captivity he allows himself to be struck by the tamer, which the most miserable ape would never suffer. The Lion will struggle with extreme energy without calculating the difference of strength between his opponent and himself, and will resist as long as he is able to move. The Ape directs all his courage and presence of mind to order his flight when he has recognised a danger that is insurmountable. He does not act like those infatuated beasts who lose their head and rush away trembling, in their precipitation paralysing a great part of their resources. A band of apes in flight utilises all obstacles that can be interposed between themselves and the pursuer; they retire without excessive haste and take advantage of the first shelter met with; a female never abandons her young, and if a young one remains behind, and is in danger of being taken, the old males of the troop go back boldly to save it at the peril of their lives. In this connection many heroic facts have been narrated. This animal has too frequently been judged by comparison with ourselves; he has been regarded as a human caricature and covered with ridicule. We obtain a very much higher idea of him if we compare him with other animals. Always and everywhere there has been a prejudiced insistence on his defects; we perceive them so easily because they are an exaggeration of our own; but he also possesses qualities of the first order.

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