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According to Huber ants seem to be aware of the approach of rain. When the sky is cloudy in the morning, or rain is indicated, the ants, who seem to be aware of it, open but in part their several avenues, and immediately close them when 'the rain commences.'

We must not dwell longer on these interesting points connected with the architecture of these little builders, except to notice the paper-made nest of the fuliginous ant of Huber, the Lasius fuliginosus of more recent authorities. This species is one which excavates its abode in wood, and is the only paperbuilder amongst ants. The oak, the willow, and other trees are occupied by these small ants, and sometimes entirely hollowed out by them; the nest consists of numberless storeys, more or less horizontal, with floors and ceilings five or six lines distant from each other as thin as a playing card, supported by vertical partitions forming an infinity of chambers, or by a series of small slender columns, allowing one to see between them to the extent of an almost entire storey; the whole is composed of a blackish and as it were smoked colour.' By what means is the paper material manufactured by this ant? Meinert thinks that it is composed of woody particles, and a substance secreted by certain mandibulary and metathoracic glands. M. Forel is inclined to agree with Meinert, but the ants which he kept in confinement and which he supplied with sawdust, refused to work with it under his observation. Leaving the nests themselves, let us notice their various inhabitants-such as eggs, larvæ, nymphæ, and the perfect insects-as the females, males, and neuters.

After the female has deposited some eggs they are taken up by the workers and deposited in little packets. The eggs increase in size after exclusion, and this growth it is supposed is occasioned by the very curious habit of the workers constantly licking them for about fifteen days, nourishment being supplied by a kind of endosmose or the transmission of some nutritious substance from without inwards through the walls of the egg. This curious fact of licking the eggs did not escape the notice of Huber, who witnessed it under one of his large bell-glasses. On looking a little closer,' he says, 'we 'find that they turn them continually with their tongues; it even appears they pass them one after the other between their 'mandibles, and thus keep them constantly moistened.' eggs are whitish or opaquely yellowish. Unlike bees, there is no appreciable difference between the eggs which produce females, males, workers, or soldiers; the larva is a small white grub with a dozen indistinct rings, footless, and eyeless; in

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most cases the larvæ are incapable of any motion with the exception of the mouth, which opens freely for food. When hungry the little grub opens its mouth, and the workers approach and disgorge honied sweets in a liquid form therein. These grubs are utterly helpless, and the workers not only feed them, but caress them with licking, clean them and transport them from one part of the nest to another, that they may have the proper degree of temperature. The larvæ which are to develope into females have the same kind of food as those which will become males and workers; unlike the bees whose queen-larva requires a different diet from the worker-larva. Sometimes the workers carry off several larvæ, smaller ones adhering to larger ones; if a larva is by accident dropped, the worker does not recover its burden until it is touched with the antennæ.

The duration of life in the larva-state is, in some cases, long; certain larvæ hatched in the autumn do not become nymphæ till July in the following year (Solenopis fugax); others appearing as eggs in April, become nymphæ about the end of May.

The nymphæ in some species are enclosed in cocoons, in others they are naked, but sometimes the same species has both kinds; they are always motionless and neither eat nor grow; the workers show as much anxious solicitude for the nymphæ as for the larvæ, cleaning and rubbing them, and transporting them from place to place as before. When a larva means to become an enclosed nympha, it fixes itself to the soil and spins a cocoon. Sometimes the nymphæ can release themselves from their coverings, the skin slitting longitudinally down the back by the lively movements of the inhabitants. M. Forel tells us that this self-liberation is not uncommon amongst the worker-nymphæ, but that the task is a more difficult one in the males and females, especially in the case of the former, when it rarely succeeds. The difficulty is caused by the large wings and abdomens of the two sexes; in such cases the aid of the workers is necessary. The help then given has been well described by Huber.

Several males and females lay in their enveloping membrane in one of the largest cavities of my glazed ant-hill. The labourers, assembled together, appeared to be in continual motion around them. I noticed three or four mounted upon one of these cocoons, endeavouring to open it with their teeth at that extremity answering to the head of the nympha. They began thinning it by tearing away some threads of silk where they wished to pierce it; and at length, by dint of pinching and biting the tissue, so extremely difficult to break, they formed in it a

vast number of apertures. They afterwards attempted to enlarge these openings by tearing or drawing away the silk; but these efforts proving ineffectual, they passed one of their teeth into the cocoon, through the apertures they had formed, and by cutting each thread one after the other, with great patience, at length effected a passage of a line in diameter in the superior part of the web. They now uncovered the head and feet of the insect to which they were desirous of giving liberty, but before they could release it, it was absolutely necessary to enlarge the opening; for this purpose these guardians cut out a portion in the longitudinal direction of the cocoon with their teeth alone, employing these instruments as we are in the habit of employing a pair of scissors. A considerable degree of agitation prevailed in this part of the ant-hill. A number of ants were occupied in disengaging the winged individual of its envelope; they took repose and relieved each other by turns, evincing great eagerness in seconding their companions in this undertaking. To effect its speedy liberation some raised up the portion, or bandalette, cut out in the length of the cocoon, whilst others drew it gently from its imprisonment. When the ant was extricated from its enveloping membrane, it was not, like other insects, capable of enjoying its freedom and taking flight. Nature did not will it that it should so soon be independent of the labourers. It could neither fly nor walk, nor stand, without difficulty, for the body was still confined by another membrane, from which it could not by its own exertions disengage itself. In this fresh embarrassment the labourers did not forsake it. They removed the satin-like pellicle which embraced every part of the body, drew the antennæ gently from their investment, then disengaged the feet and wings, and lastly the body, the abdomen and its peduncle. The insect was now in a condition to walk and receive nourishment, for which it appeared there was urgent need. The first attention, therefore, paid it by the guardians was that of giving it the food I had placed within their reach.'

These facts recorded by Huber have been confirmed by Fenger and Forel.

The cast-off exuviæ of the cocoons are in some species removed by the workers, and heaped up around the gates of the nest, or they are carried away to a distance, or mixed with the materials of the nest. The first instinct exhibited in the young worker-ant is a maternal one; as soon as it has learnt to know where and what it is, which requires some days, the young pale-coloured worker exhibits the same care and anxiety for the yet unhatched cocoons as the elders. One important duty of the workers is to attend to the wings of the newly-born males and females, which they carefully extend and unfold; without this assistance the wings would remain folded up and useless for flight. Leaving the workers for a time, let us look at what takes place amongst the males and females. As amongst bees so amongst ants, the males are incapable of work, seem to lounge about the doors for some days, not knowing what

to do, and hide themselves in the soil; they cannot defend themselves against enemies, and indeed, according to M. Forel, are incapable of distinguishing precisely between the neuters of their own swarm and foreign foes; they depend on the neuters for guidance and for food; if they wander away they must be brought back again by the neuters. But it is far otherwise with the female, which amongst ants at all events is 'the superior creature.' They help the neuters in their work, transport the larvæ or nymphæ from place to place, on required occasions, and follow readily the movements of the neuters, which, however, surpass them in intelligence. The fecundation of ants has been admirably described by Huber, with, to use the words of M. Forel, an exactness which leaves nothing to 'be desired; but Huber does not mention the innumerable varieties and exceptions which complicate this question. Speaking particularly of Lasius flavus, M. Forel tells us that males and females are hatched about the same time, that the two sexes are found nearly in all the swarms. As a rule the

males are much more numerous than the females. After promenading about for some days, on some fine afternoon in August, increased agitation and bustle are seen on the surface of the ant-hill; some of the males fly away, other pursue the females; the scene becomes more and more lively, the neuters are more and more excited; now the males take flight and mount up to a great height, forming enormous swarms if the males and females of several adjacent ant-hills leave them on the same day. At this moment the males and females of the same species, and often of different species, mix together in the air promiscuously. The males of F. flavus, which are much smaller than the females, attach themselves to them, three or four together, and are thus carried through the air. The swarms thus sometimes obscure the heavens. Such swarms are generally to be seen on a fine day after a period of rain. Meanwhile what are the wingless neuters doing? They lose no time, but seek for the fertilised females for the preservation of the nest; these they discover on the surface of the ant-hill, or on stems of grass not far away, for before the general flight into mid-air, a certain number of females have there been fertilised; and now a curious spectacle presents itself. The neuters throw themselves upon the females, tear off their wings and make them enter the nest. The aerial males and females never return to their former abode, to which the fertilised females especially show a decided aversion. 'winged ants,' says Huber, when they quit the ant-hill, keep 'their back continually towards it, and go off in a right line

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'to a distance, from which it would be no easy matter to per'ceive it. We might from this infer that they never return to it. But I did not confine myself entirely to this observation, for 'I kept sentry from the time of their departure until night, 'and even several days in succession, to be fully assured that they did not return to the ant-hill. In this way I have 'arrived at the conclusion that their return is one of those 'fables with which we have been a long time amused.' On this point also Huber is confirmed by Forel.

Everyone who has examined an ant-hill in the autumn must have observed a number of females without wings: what has become of these organs of flight just now so iridescent and beautiful? Huber shall tell us in his own graphic language. Having caught eight females, he placed them with some moistened earth in a garden vase covered with a glass receiver.

'It was nine o'clock in the evening; at ten all the females had lost their wings, which I observed scattered here and there, and had hidden themselves under the earth. I had allowed the occasion to pass by of witnessing the separation of these fragile members, and of determining if possible what had produced it. On the following day I procured three other females in union with their males, and this time I observed them with the greatest attention from the moment of their fecundation until nine in the evening, a period of five hours. But during this time nothing was done to denote the approaching loss of their wings, which remained still firmly fixed. These females appeared to be in excellent condition; they passed their feet across their mouths, they glided them over the antennæ and rubbed the legs one against the other. I could not conceive what could retard the fall of their wings, whilst the other ants had lost them so readily. It is true that I placed those of which I am now speaking in a very strong box, completely closed, whilst the former were deposited in a transparent vault, offering not the slightest appearance of a prison, and upon a ground more natural than the bottom of a sand-box, where there was no earth. I had no idea that a circumstance so trifling would have any influence upon these ants; however, having learned that it was necessary to place them as the first, I took some earth and strewed it lightly over the table, and then covered it with a bell-glass. I yet possessed three fecundated ants, one of which I introduced under the recipient. I induced her to go there freely, by presenting to her a fragment of straw, on which she mounted, and upon this I conveyed her to her new habitation without touching her; scarcely did she perceive the earth which covered the bottom of her abode, than she extended her wings, with some effort bringing them before her head, crossing them in every direction, throwing them from side to side, and producing so many singular contortions that her four wings fell off at the same moment in my presence. After this change she reposed, brushed her corselet with her feet, then traversed the ground, evidently appearing to seek a place of shelter. She seemed not to have the slightest idea that she was con

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