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Quarterly Journal of Microscopical Science, vols. 39 and 40.

Footnote 4:

A nymph is the free-moving active equivalent of the chrysalis amongst moths and butterflies.

Footnote 5:

Nests built in chemical glass tubes and thus under close observation.

Footnote 6:

Chambers's Encyclopaedia.

Ant language--Stridulatory organs--How white ants communicate--Conversation through convulsions--Nests in tubes--Detection of a "crepitus"--Mutual recognition--Cannibalistic propensities--Royal jealousy--Loyal assassins--A kingly feast--Methods of feeding--Foundation of colonies--Swarming habits.

IT used to be supposed that such communication as ants are capable of holding with one another took place entirely, or almost entirely, through the mutual stroking of the antennae, and Sir John Lubbock was unable to satisfy himself, after numerous experiments, that they could either hear or utter any sound. It is now known, however, that not only can some ants emit various sounds at their pleasure--as, indeed, is sufficiently obvious in the case of one or two species--but also that they possess special structures enabling them to do so, and the existence of which is inconceivable, except on the supposition that they both hear and attach a meaning to the notes thus evolved. Thus at a meeting of the Entomological Society held in the year 1893, Dr. David Sharp declared that "examination revealed the existence in ants of the most perfect stridulating or sound-producing organs yet discovered in insects, these being situated on the second and third segments of the abdomen in certain species. The sounds produced were of the greatest delicacy, and it appeared doubtful whether the microphone would be able to assist the human ear in their detection"--which, indeed, it has not yet done. Later, in the work above mentioned, Dr. Sharp remarks, "In many ants these parts"--that is to say the abdominal segments--"bear highly developed stridulating organs, and the delicacy and perfection of the articulations allow the parts to be moved, either with or without producing stridulation."

As these ant utterances are not sufficiently loud to be audible to our human ears, they must, I suppose, be inferred from the existence of the organs above-mentioned, and the way in which they work; but this is surely sufficient data to go upon, since it is hardly possible for one hard substance to grate upon another silently. Forel, accordingly, as well as Janet and other observers, now believe sound to be one of the principal means by which ants hold converse with each other, and it is interesting to find that Grassi and Sandias have arrived at the same conclusion in regard to white ants, or termites. Their opinion, together with the facts upon which it has been founded, is thus expressed:--

"Several writers have mentioned the convulsive movements characteristic of Termites. These movements, or quiverings, are easily observed in Calotermes, and may be repeated periodically at very short intervals, almost at the frequency of the pulse-rate. In the act of quivering, the legs are held motionless, whilst the body is shaken forwards and backwards. Sometimes a white ant may stop, whilst running, in order to quiver one or more times. Occasionally these convulsive movements are repeated a few times only, and then stop altogether; but at other times they recur after a few seconds' or, at most, a few minutes' rest, and may thus be continued, sometimes, for hours, at regular or irregular intervals. In the intervals between successive convulsions the insect remains still, or progresses for a short distance only. These movements are executed by all members of the colony except the newly hatched ones. I have satisfied myself," continues Professor Grassi, "by careful observation of the phenomena exhibited in tube-nests, that these convulsions serve as a cry to summon help or give alarm, or as a lament: in short as a mode of intercommunication."

The same observers then go on to tell us that if white ants are disturbed in any sudden way, as by the too rough shaking of their nest, or by a light being suddenly flung upon it, or if otherwise annoyed, "all the members of the colony begin to quiver, except those that are running briskly about in search of a better situation." When dying, too, they will sometimes quiver in this way, at intervals of a few minutes, for as much as an hour or two, or even longer. Should an enemy--such as those we have been speaking of--be introduced of a sudden into the nest, the less valiant members of it prefer to run away, but in the midst of their retreat they may often be seen to stop and quiver with unusual energy. Their object in these cases seems to be to raise a general alarm, nor is it long before they are successful. Again, if whilst one insect is burrowing into wood another outside should quiver in this way, the burrower quickly comes out, as though in response to some signal of alarm. From all this it seems evident that these curious movements must be accompanied by some sound, or sounds, inaudible to our human ears, and perhaps having a varied range, and with considerable power of modulation. To produce them, however, some stridulating or other organs would seem to be necessary, and of these, though they must, if there, be visible under the microscope, Professor Grassi says nothing. Possibly, however, sounds may be produced by the rubbing together of various parts of the body without any special apparatus having been developed, in which case the language, if we may call it so, cannot be so rich or copious.

Members of the same ant community are known to recognise each other, and this is no less the case with the white ants, or termites. Thus when a few of the latter were removed from the termitary and returned to it after five or six hours, the population showed no signs of alarm--not scurrying wildly about as they would have done had strangers been introduced--but remained quiet and orderly. It was objected, however, though I cannot see the force of such an objection, that the exiles, on their return, would have instantly recognised their old nest, and thus, knowing exactly where to go and what to do, they would have created no disorder, and consequently roused no suspicion, amongst the other members of the colony. To meet this theory Professor Grassi provided one of his colonies with a new nest from which he excluded a certain number of individuals, so that when these were introduced into it, an hour or two after their companions had settled down in their fresh abode, it was, of course, quite unfamiliar to them. In spite of this, however, they caused no disturbance, but were clearly recognised as friends. When, however, a few strangers of the same species were introduced, they created great alarm amongst the rightful proprietors, who scattered in all directions. In a little while, however, all was again quiet, and as no fighting was observed, it would appear that, amongst the termites, strangers from different nests soon become friendly with one another. This, however, applies to the commoners only, it is not the same where royalty is concerned. Thus when a second king and queen were introduced into a termitary already provided with a pair, they were at once attacked by the subjects of the latter, who loyally bit off their legs. Two days afterwards the reigning queen was herself seen to attack the male pretender, or rather unfortunate victim of scientific curiosity. He, however, though without legs to assist him, managed to drag himself away, but was afterwards found dead, with the outraged queen nibbling vindictively at his mutilated stumps. Next day the stranger queen was also found dead, and the same thing always happened whenever the experiment was repeated. Sometimes, indeed, the supernumerary royal pair, or pairs, had disappeared altogether, from which it seems clear that they must have been not only killed, but eaten.

Cannibalism, indeed, is rather an institution than a vice in the termitary. To begin with, the cast skin of every member is eaten by the others as a matter of course. With this view, any individual who is ready to moult receives the skilled aid of two or more assistants, who either eat the outer portion of their friend, bit by bit, as they shred it off, or else carry it away whole and devour it at their leisure. Sometimes, moreover, one, after licking another affectionately, in the way that ants do, may be seen to give it a covert bite, as though desirous of something more filling, whilst any sick member is eaten by its companions before it is dead. Royalty is not exempt from this treatment, and, on one occasion, nine individuals, including one soldier, were observed by Professor Grassi in the act of enjoying a meal on the body of a substitute king who was in process of moulting. The wretched animal was still alive, and writhed all over its body, to free itself from the torture. The nine assassins were probably annoyed at the light, for they at once stopped eating, and jointly carried off the victim to a darker part of the nest. Meanwhile many others crowded up to partake in this feast of royal flesh.

A soldier, too, has been observed to kill and partially eat one of its worker companions, nor is it altogether uncommon for an individual of any class, after licking, for some little while, the leg of another, suddenly to snap it off. The bond of union, therefore, though sufficiently developed to allow of an elaborate social organisation, is not so strong between members of the same termitary as it is in the case of ants, amongst which latter such unseemly conduct is never known to occur. So, too, unless a particular chemical substance, which seems to have a maddening effect, be flung amongst them, ants of one community never attack each other. Amongst white ants, however, warfare will occasionally break out within the nest, more especially if this be disturbed, in which case the soldiers are apt to turn savagely on those nearest to them, perhaps considering them as the cause of the calamity. Still, upon the whole, order, and, if not friendship, at least co-operation, is conspicuously displayed, and the majority often interfere to put a stop to such individual or partial combats as may from time to time break out.

There is more excuse for the soldier termites in their cannibalistic propensities, since owing to the special development of their jaws, which are long and slender, they are unable to triturate wood, which is the basis of diet of these insects. They might die, therefore, but for such occasional lapses, were it not the common practice for all members of the community to feed one another, though the soldiers, for the above reason, are much more dependent on such aid. The food thus administered has just been swallowed by the individual who parts with it. Such transfer is performed in two ways, the first of which is familiar enough--that process, namely, known as regurgitation--but the second and more staple one is too peculiar to be dealt with in a non-scientific work. When a termite regurgitates, an exceedingly small round pellet of reddish-brown colour may be seen, by attentive observation, to form about the mouth, and gradually to increase in size till it becomes plainly apparent, and is seen to consist of food--that is to say, wood--which has previously been swallowed, in a moistened and softened condition. Sometimes this pellet is used for building purposes, but often another termite comes forward, receives, and swallows it.

Another article of diet which has a peculiar efficacy, and is used for a certain purpose, has been already alluded to--viz. saliva. This, we are told, "issues," when required to do so, "as a colourless and distinctly alkaline liquid. It collects on the labium as a small drop, which may be employed either as a cement in building or as food for others. These may either possess themselves of the drop and then retreat a little way in order to swallow it gradually, or they may receive it from the one which secretes it and clearly provides it for them as an article of diet. The assimilation of a drop requires a certain number of acts of deglutition, which may be counted, and are usually four or five." Very young larvae are fed after this fashion, until sufficiently advanced to be able to swallow wood-meal. Under this course of diet the abdomen becomes remarkably transparent, and this, in older individuals, is an indication that they are being bred up by the workers to become royal substitutes. The development, therefore, of termites from the larval to the perfect, or, at least, the sexually perfect form, seems to be wholly dependent on their being fed with this substance.

As is well known, the body of the queen termite, in the African and other tropical species, swells, when about to lay, to an enormous size, but this is not nearly so noticeably the case with her European representatives. Neither is a cell, in this case, constructed for her accommodation, but the royal pair, whether they are true king and queen, or only substitutes, "remain, in close proximity, in the heart of the nest, where the inmates are always most crowded." They are not imprisoned, therefore; but can go from one place to another, should they, as sometimes happens, wish to change their situation. In this they would seem to be happier than their more specially accommodated royal cousins, but no doubt, with the latter, or at any rate with the queen, the instinct of locomotion ceases with the capacity to indulge in it. The purpose of the specially made cell is probably rather to guard than to restrain the queen.

In regard to the swarming of white ants--another habit in which we are reminded both of ants and bees--with the subsequent founding of a new colony, Professor Grassi has the following remarks to make. They apply more especially to the larger of the two European species, viz. Calotermes. "Before swarming," he tells us, "they collect near one of the exit-holes of the termitary, and when the proper time comes, issue from it in ones or twos, so that the twenty or thirty members who are ready to take flight emerge in perhaps a quarter of an hour. Once outside, they run upwards, if the locality admits of it, for a few metres, and then only do they take wing. In a room they fly towards the light, and if a wind is blowing they follow its direction. Some, becoming tired, settle soon upon trunks of trees, and all may do this eventually. Here they group themselves into pairs, the males and females of which must frequently be derived from separate nests, since the sexes swarm separately; this acts as a safeguard by which Calotermes habitually avoids in and in breeding. Matrimonial alliances having been thus formed, the work of excavation commences, each pair seeking for some decayed spot in which to bury themselves and become, in time, the parents of a fresh community. The wings, by this time, have been got rid of. They may be shed by coming into contact with an obstacle, or by getting damp and adhering to some spot, while the insect continues to move. But, if not favoured by chance, the Calotermite purposely rids itself of these now useless encumbrances. Thus four perfect insects were captured after flying about the room, and put under a piece of rotten wood. Hardly had they settled when they stripped off their wings by resting the tips against some projecting corner of the wood, and then moving backwards a little, so that the wings bent near the base, broke, and dropped off. When rid of them they began to gnaw the wood, at first along and then across the grain. When they encountered each other by chance they first threatened to bite one another, and then ran off in opposite directions. This was because they were of the same sex. Had they been of opposite ones, an attachment, under such circumstances, would no doubt have been formed between them."

This is all the space which I can afford to these interesting insects. There are many other points in connection with them which I might have touched upon, but I thought it better to say less about what may be read by anyone in a score or so of works, and select as my text-book a series of the closest and most interesting observations, which lie buried in the pages of a scientific journal not at all likely to meet the public eye. Where possible, I shall be guided by the same or a similar principle throughout this small work.

Footnote 7:

Nature, March 23rd, 1893.

Footnote 8:

The Cambridge Natural History, vol. 6, p. 134.

Footnote 9:

Quarterly Journal of Microscopic Science, vols. 39 and 40.

Ants and white ants--Guest insects--Ants'-nest beetles--Doubtful relations--A strange forbearance--Yellow ants and white wood-lice--Beetles fed by ants.

FROM what has been said about the Termites in the last chapter, it is clear that they very much resemble ants in their habits, so that it is no wonder that they have long passed for ants in popular estimation. Such a similarity is quite enough to justify one part of the name, as names go; and as for the word white, which entomologists are always complaining about, that is quite near enough too, for though their bodies are not white, but yellow, yet the greater part of them--the soft fat abdomen, which particularly catches the eye--is of such a light yellow that it suggests white in contrast to the darker colouring of most ants. Scientific men--unless their particular science is philology--are dreadful pedants in regard to names, and always want to substitute their own manufactured ones, which have no real life in them, for what has sprung up naturally on the lips of the people. Thus, instead of hedge-sparrow--a name that explains itself to anyone who has seen the bird and knows something of its ways--ornithologists would have us say "hedge-accentor"--a preposterous concoction--and stormy petrel should, according to them, be "storm-petrel," because the bird itself cannot be stormy, whatever the sea may be. No imagination behind the common use of language, then. No poetic transference of attributes. All is to be as prosy as professors can make it, and "we must speak by the card, or equivocation will undo us." But names, which are a part of language, come into being as language itself does--spontaneously, that is to say, and by a natural growth. They are right because they exist; and the very errors contained in them--telling, as they do, of popular beliefs and superstitions--are of greater and wider interest than the rectitudes of a few pedants. Could they play with substance as they can with breath, these wise simpletons would first draw up a theory of anatomy, and then annul all bodies that did not conform to it. Such and such a word or name is wrong, in their eyes, though it exists quite as naturally as any nerve or muscle, and is quite as tough though only made of air. This last they will find if they live long enough, and "hedge-sparrow" and "stormy petrel" will survive all their lifeless substitutions, though embalmed in many dull paragraphs of many dull books.

But let us come back from words to things. Much as the white ants resemble real ones in many of their habits, the more remarkable ones that distinguish the latter are not practised by them. They make no slaves and keep no domestic animals--at least I have never heard of their doing so, though in natural history one must always be prepared for new discoveries. Many insects do, in fact, live with them in the termitary, just as others live in the formicaries of ants, and it is quite possible that, when these have been better studied, some of them will be found to have special relations--involving mutual intelligent action--with their landlords.

Footnote 10:

Footnote 11:

Kirby, Marvels of Ant Life, p. 100.

Ant parasites--Fleet-footed brigands--Honey-stealing mites--A strange table companion--Privileged cockroaches--Ants and their riders--A fly-ride on beetle-back.

LEAVING the beetles--though as there are probably some thousands that live habitually in ants' nests, we have said very little about them--we may glance at an extraordinary little creature, in appearance something like a wood-louse with a fish's tail, that resides with certain ants on the footing of a freebooter, constantly stealing from them, and eluding their resentment by extreme activity, living, as it were, in a state of perpetual motion. The legs of these persistent yet withal timid brigands are many and long, which, together with their shape and general lightness of build, enables them to run with great speed, so that they easily outdistance the ants, and, escaping to some less frequented part of the nest, with which they are always well acquainted, remain there quiet for a time. Should a single ant approach them, however, they immediately run away, or, if forced by circumstances to be near one or more--which, in an ants' nest, must be often difficult to avoid--make a point, apparently, of never keeping still, as though to confuse them, or, perhaps, to be the better able to dash off at any instant.

The extraordinary looking insect shown towards the top is the lepismid, or fleet-foot, who lives by stealing food from ants when they are in the act of passing it from one to the other. The atemeles beetle shown below is begging food, which will not be refused, from the ant in front of him.

The parasite, whilst stretching out as far as it can from the body of its host, in quest of food, remains, all the while, attached to the latter by the disc in which its body ends. It can, however, leave one ant larva for another, though Professor Wheeler, to whom we owe this interesting discovery, believes that it does this "with great reluctance, and only under urgent circumstances, such as extreme hunger, the death of the larva to which it is attached, and perhaps, when fully mature, and about to pupate." So long, indeed, as its original host, on whose body, when quite young, it was probably hatched from the egg, continues well and is well fed, it has no reason to seek farther, since all its wants are provided for. It is not only fed by the worker ants, but shares in any other of the benefits which these may bestow upon the rising generation of the nest. Thus, if they move larvae, as is customary, to give them change of temperature, and produce the requisite hygienic conditions, the parasite is moved along with them, and it is cleaned also--a still more important advantage possibly--at the same time as they are. At such times the ants never seem to notice the uncouth incubus upon the bodies of their infant sisters, though one would suppose the difficulty would be not to do so. They are, it is true, blind, or nearly so, but it seems strange that their sense of touch, which is no doubt delicate, should not be able to inform them, since the parasite, though small enough, absolutely, is of great size regarded as an excrescence on its host's body. This probably is the way in which the matter presents itself to the ants, if they think about it at all, for since the two lives are passed constantly together, and are subjected to the same conditions, it is likely that they share one smell between them.

But this curious parasitic relation between ant and fly is not confined to the larval stage of each. Continued observation led to a further discovery which I give in Professor Wheeler's own words: "As the days passed, the mature ant-larvae spun their brown cocoons one by one, and one by one the mature commensals disappeared. No traces of them could be discovered. The only remaining resource was to open the cocoons. Five were opened, and in two of recent formation commensals were found! Having shared the table of their host, they had come to share its bed as well. The dipteron had pupated after the manner of its kind, forming a puparium, that is, instead of spinning a cocoon like the ant larva: the dead larval skin, somewhat shrivelled and contracted, was used as an envelope, and within this the pupa proper was found. In all cases the puparium was located in the caudal pole of the ant cocoon, and was immovably stuck to the wall of the cocoon, its anterior end directed towards the cephalic pole" . But what, asks Professor Wheeler, does the commensal larva do "while the ant-larva is weaving its cocoon? Does it move about to avoid the swaying jaws of the spinning larva? or does it take up its position, from the first, at the posterior end of the larval ant, and there remain motionless while the posterior pole of the cocoon is being completed? It is very difficult to answer these questions."

One might think that young ants thus deprived, day by day, of a portion of every meal, would be stunted in their growth, and not make such large and healthy workers as those who had never been encumbered with a parasite. This, however, does not seem to be the case, and no difference can be detected between the one and the other. Perhaps, therefore, ants habitually eat, if not more than is good for them, at least more than they require. This is the case almost universally amongst civilised men, at least in Northern Europe, and with savages to a still greater extent whenever the wherewithal is at hand. In the above case we have, as Professor Wheeler remarks, a very perfect example of what is termed commensalism, in the original meaning of the word--that is to say, of two or more individuals dining together at the same table. As applied to natural history, the individuals in question must be of different species, but it is not often that the definition otherwise is so rigorously adhered to.

Enjoyment seems to be the only motive the fly has for riding on the back of the African beetle shown in the upper part of this illustration. Beneath is shown the well named honey-pot ant with its distended body full of honey, which it gives away to any hungry working ant.

Footnote 12:

Footnote 13:

Footnote 14:

The American Naturalist, December, 1901.

Footnote 15:

Ibid., November, 1900.

Footnote 16:

The Entomologist's Monthly Magazine , August, 1896.

From biped to quadruped--Flies that borrow wings--Sit-o'-my-head--A novel cradle--Flies that kill bees--Nature's sadness--Consolations of the future--The Tachina fly and the locust.

"one whose hand, Like the poor Indian, flung a pearl away Richer than all his tribe."

For what can be imagined more glorious to possess, speaking of physical attributes, than the power of flight?

Poised in the air, the buccaneer fly selects its victim from the bees issuing from a hive, pounces on it like a winged fury, and kills its hapless prey. The insect depicted beneath is protected from its enemies by its strange resemblance to a dead leaf.

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