CHAPTER I
“The natural system”—A middle course—Neuropterous insects—White ants and their ways—Kings and queens—A royal diet—Secondary majesties—Soldiers and workers—Ant invaders—Methods of warfare.
IF there is any plan in this little book it will, no doubt, appear in time to its readers, but I myself am only quite clear as to this, that, not being of a scientific nature, it will not include a definition of an insect. Why should it? Everybody knows what he thinks an insect is, and those who may be willing to have their ideas on such a fundamental subject disturbed will rightly consult some work of greater authority than this can pretend to. So instead of worrying myself, and others, about what insects really are, or what are not really insects, as, for instance, spiders, centipedes, scorpions, and the like, all which I propose to include in my tale—should they happen to present themselves—I shall confine myself to saying something about what some insects do, and I shall let one suggestand lead to the discussion of another, quite at haphazard, and without any attempt at system or classification whatever. This, in fact, is my own idea as to what is “the natural system,” and the only trouble about it is knowing where to begin, because, as there are some 300,000 known insects,[1]and any one of them will do as well to start from as any other, there is a greatembarras de richesses. In such cases the usual thing to do is to take either the head or the tail of the series—to commence with theHymenoptera, which include the highest and most intelligent forms, such as the ants and bees, or else with theCollembolaorThysanura, which are understood to contain the lowest. I shall not adopt either of these methods. TheNeuroptera, as far as I can make out (and if they don’t it doesn’t matter), stand somewhere about the middle, and with them accordingly—as being between the two extremes—I decide to break ground. Having done so, as I said before, I may go anywhere—absolute freedom will be mine. Like Plato, I can follow the argument whithersoever it leads; inspired with which reflection I hasten to begin it.
Though the order of neuropterous—which, by the way, means nerve-winged—insects does not contain any ants, yet the so-called white ants or termites—which are very like ants in their ways, and almost, or quite, as interesting to talk about—are included in it. They are commonest in tropical or, at any rate, very hot countries, such as Africa, Australia, and South America, and here the conical, or dome-shaped structures, made of red earth, which they erect above the surface of the ground, and which contain the greater part of the nest, are of such dimensions as to take a very prominent part in the features of the landscape. Often they are covered with vegetation, including bushes, or even small trees, on which, in Africa, antelopes are accustomed to browse. In Australia there is no reason, that I can see, why kangaroos should not, at least upon the grass which must often clothe them, and which is their staple of food.
WHITE ANT HEAPS
WHITE ANT HEAPS
WHITE ANT HEAPS
These great mounds are made by the white ants, and contain their nests; but large and strong as they are, the ant-eater breaks them down and devours the ants. A queen white ant is shown at the right-hand corner with the extraordinary development in which the eggs are carried.
These great mounds are pierced in every direction with innumerable galleries, leading to and from the various cells and chambers in which the domestic economy of the white ants is principally performed, one of which, known as the royal cell, contains the king and queen, and is situated beneath all the others. Not all white ants, however—for there are several species—are governed or presided over in this way. Grassi, who studied them in Sicily,[2]declares that the whole of the Termitidæ, whether belonging to Southern Europe or the still hotter countries from which they have, no doubt, been unknowingly imported, fall into two primary types. In the first of these the colony is presided over by a king and queen, representing the fully developed male and female forms, which have once, unlike the workers and soldiers—for, like ants, these insects are divided into castes—possessed fully developed wings, which they have subsequently got rid of in the same way that the queen ant does hers. In the second type the colony possesses several kings and queens, butthese, though they marry and produce offspring, are not perfect males and females, and never possess wings. They are, in fact, produced artificially by the working termites, just as the hive-bees are able to make themselves a new queen—should they require one—by feeding an ordinary worker with royal jelly, and by a method somewhat similar though not precisely the same, the royal substitutes being fed, not on any extraneous substance, but on a salivary fluid secreted by the workers themselves—saliva, in fact. The colony, however, is, in this case, not founded by the royalties thus bred up, but by a portion of a pre-existent colony which, migrating from the parent nest, takes this method of augmenting its numbers.[3]
In the termite nest, as amongst ants, all members work for the good of all. The soldiers, which are furnished with large heads and long scythe-like jaws, take upon themselves the duties of attack and defence, though in some species they only do so when the enemy is of a formidable nature, leaving unimportant foes to their less specialised companions. These are equal to such inglorious tasks, but when the colony is invaded by hostile members of their own race, or by some fierce ant enemy, they retreat into the inner recesses, leaving the danger and honour to others. Such an enemy isCremastogaster scutellaris—or call him Cremas—who, though never invaded by the white ants, enters their nest—or termitary, to use the learned word—intent upon massacre. Under such circumstances “the soldiers place themselves, with gaping mandibles, waiting for any ant that may come within reach. They then snap their jaws rapidly, shearing offantennæ and legs, tearing the abdomen, or even cutting the ants in two. The soldiers’ mandibles are seen to act like extremely sharp shears.”[3]This should be somewhat discouraging for the ants, and, indeed, they seem rather shy of the soldiers, avoiding their heads, and “only daring occasionally to attempt to lop off their mandibles.” Their more considered method, which they adopt whenever practicable, is to approach them from behind, and bite their abdomens, the soldiers, on their part, endeavouring to protect this vulnerable portion—and it is a fairly large one—of their anatomy by creeping backwards under pieces of wood or stones, from which the head, with its murderous jaws, is alone allowed to project.
In these encounters the advantage does not seem to lie so decidedly with the ants as to explain their conduct in making the invasion, since peace, according to Professor Grassi’s observations, is usually concluded “after about an hour’s conflict, with a certain number of killed and wounded on both sides.”[3]As a result, however, it would appear that the ants often remain in possession of a portion of the nest, whilst the original occupants have to be contented with what remains. If this, therefore, is their object, the invaders have carried the day, but if, as seems likely under natural conditions, they should prefer to return to their own home, they can hardly be said to have done so. Information seems wanting on these points.
As with ants, war is also waged between the various species of Termitidæ.Termes lucifuga, for instance—for where there is no English name there is nothing for itbut to speak Latin—is, though much smaller, a terrible enemy ofCalotermes. The soldiers of the latter can, indeed, without much difficulty, cut their own in two, but their greater activity is often more than a match for the superior strength of their opponents. The workers are more easily disposed of, but with these the soldiers ofCalotermesdo not often concern themselves. They are left to the nymphs[4]and larvæ, the equivalents, with the latter species, of a true worker caste which has not yet been developed amongst them, as it has with others of the family. When Professor Grassi placed a worker of Termes in one of his Calotermite tube-nests[5]it was at once placedhors de combatby a nymph (somewhat a shrewish one) of the latter, which, rushing upon it, cut off a portion of its mouth. Other nymphs, as well as several large larvæ, then hurried up and proceeded to further the good work by severing the unfortunate creature’s legs, and tearing open its abdomen. In all this the soldiers took no part until one, towards the end of the struggle, advanced and added his single bite to those which had been so plentifully bestowed. Similar observations were made upon various other occasions, from which it appears plain that, as before remarked, the soldiers of this—very probably of all the termites—are accustomed, purposely, to reserve their strength for foemen worthy of their steel.
It will be seen from the above account that termitesdiffer from true ants in one very important particular, namely, that they are as active and free-moving in the larval and pupal states as in the mature, or imago, one. “The termite society,” indeed, “consists, for the most part, of wingless sexually immature individuals, children potentially of both sexes, which do not grow up.”[6]Out of the majority of these the worker caste, when it exists, is formed, whilst a much lesser number develop into the large-headed, long-jawed soldiers. Both of these castes, apparently, are produced independently of sex, that is to say, they are potentially either males or females, and not composed exclusively, as is the case with ants and bees, of undeveloped females. Only the genuine king and queen of the termitary would seem to have attained the true imago state; such substitute royal forms as the workers, by feeding the larvæ with saliva, are able to produce, retaining larval characteristics, though sexually mature—a phenomenon scientifically known asneoteinia. As with the bees, these potential future royalties are bred up by the working termites to meet possible future emergencies. They are never allowed to leave the nest, and, should any accident befall the reigning king and queen, a pair of them are chosen to rule and produce offspring.