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neuter being scarcely two lines in length, and is abundant anywhere, raising its little mounds which carry off the rain from its dwelling, in orchards, meadows, or heaths. Huber tells us that these yellow ants are extremely jealous of the aphides, often taking them in their mouths and carrying them to the bottom of the nest, or bringing them to the top. We cannot wonder at this when we learn that this aphis secretion is the little ant's only source of food. Huber placed some of these yellow ants in a glazed box with their aphides upon some soil; he also placed with them some growing plants, which he watered occasionally, so that there was no lack of food

'The ants made no attempt to escape; they appeared to have nothing to desire; they took care of their larvæ and females with the same affection as in their own nests; they paid great attention to the aphides and never injured them; the latter did not seem to labour under the slightest fear; they allowed themselves to be carried from place to place, and rested in the spot chosen by their guardians. When the ants wished to displace them, they began caressing them with their antennæ, hoping thereby to induce them to abandon the roots or to withdraw their proboscis from the cavity in which it was inserted; they afterwards took them up gently in their mandibles, and carried them with the same care as the larvae of their own species.' (P. 225.)

But it is not only the aphis itself, whether young or adult, that the yellow ant takes care to introduce within its nest; the eggs of the aphis are eagerly sought for and brought home. We call the little oval-shaped bodies which may be found adhering to various plants in the autumn eggs' for convenience sake, but really they are not eggs at all in the true sense of the word. It is well known that the aphides produce young ones without the intervention of the male sex-this was shown by Bonnet in 1745, and has been repeatedly verified; that for many months these young aphides are all females, they in their turn being virgin mothers capable of reproduction; these are produced alive and undergo no metamorphosis. In the late autumn or early winter, however, innumerable quantities of small, often black oval, bodies are produced; so that it would seem that we have a combination of viviparous generation at one season, and of oviparous generation at another, in the same insect. But this is a mistake: the socalled egg is a nymphal form of aphis, which differs in no respect from the ordinary nympha whilst yet within the body of the parent, excepting that it is enveloped in a covering. Gould noticed these little black bodies in ants' nests, but wrongly thought them to be ants' eggs which would produce

females; there is not the slightest doubt, however, as to their true nature. Huber calls them 'eggs,' but it is evident that this most accurate observer held the opinion-first, we believe, expressed by Bonnet-that they are young enclosed in a covering or cocoon. This covering is nothing more than an 'asylum, of which the aphides born at another season have no 'need; it is on this account some are produced naked, others 'enveloped in a covering. The mothers are not then truly 'oviparous, since their young are almost as perfect as they ever 'will be, in the asylum in which nature has placed them at their 'birth.' (P. 246.) We have over and over again satisfied ourselves that this is the true nature of the so-called aphis eggs. If these eggs are collected in the late winter and brought into the house, they will after a time shrivel up, thus showing that the contained aphis is dead. Bonnet vainly attempted to preserve these bodies alive in his room till the following spring; he considered that they died from want of proper moisture. We know that in the natural state when adhering to various plants out of doors, these aphis-cocoons, at the return of spring, burst their membranes and countless thousands of the insects are produced. That Bonnet was correct is curiously enough shown by the behaviour of the yellow ant towards these captured aphis-cocoons. Huber again shall tell us the story. Speaking of this species of ant (Lasius flavus) the fourmi jaune of our author, he writes:

'On opening the ant-hill I discovered several chambers, containing a great number of brown eggs; the ants were extremely jealous of them, carrying them away, and quickly too, to the bottom of the nest; disputing and contending for them with a zeal that left me no doubt of the strong attachment with which they regard them. Desirous of conciliating their interests as well as my own, I took the ants and their treasure, and placed them in such a manner that I might easily observe them. These eggs were never abandoned.' (P. 244.)

So much for the jealous care with which these aphis-cocoons meet with from the ants. In a former passage (p. 232) Huber says that the ants approached the eggs,

'slightly separating their pincers, passed their tongue between them, extended them, then walked alternately over them, depositing, I believe, a liquid substance, as they proceeded. They appeared to treat them exactly as if they were eggs of their own species. It appears, then, that ants know everything that is necessary to the preservation of these eggs; they pass their tongue constantly over them, and invest them with a glutinous matter, which retains them together. They, in consequence, are preserved until the period when the aphides quit them; they employ, then, the same means to preserve their cows, if I may

use this expression, that M. Bonnet supposed would preserve these eggs, and secure their disclosure in the spring.' (P. 246.)

If, therefore, we may regard the aphis as the cow of the ant, we may, perhaps, be justified in considering its cocoon as the calf.

There can, we think, be no doubt that the curious relationship existing between ants and aphides is the result of mutual service. The aphis yields its sweet secretion voluntarily for the benefit of the ant; the ant confers a benefit on the aphis by removing from it the viscid secretion. This latter supposition is rendered probable by the fact that if the ants do not come to relieve them, the aphides deposit their juices upon the leaves of trees or elsewhere; and this is conformable to Mr. Darwin's belief, that the instinct of each species is good for itself, but 'has never, so far as we can judge, been produced for the ex'clusive good of others.' Certain gall-insects, as well as the aphides, supply some ants with a similar secretion, as has been witnessed by Huber, Forel, M. Delpino, and others. Huber compares the movement of the antennæ, in this case, to the play of the fingers upon the keys of a pianoforte.

Aphides and gall-insects, in Europe at least, are the great food-providers for ants, but M. Forel says that the differences. in this respect are enormous according to the species of ant.

'Leptothorax is never seen to carry the aphides; it is the same with Pheidole, Tapinoma, Hypoclinea, and A. structor, as I think these ants have other means of subsistence; some are more carnivorous than others, as Pheidole, Tapinoma, Tetramonium; others directly lick the juices of flowers and of trees (Leptothorax, Colobopsis); others, again, store up grains, which they cause to germinate in part so as to supply them with sugar (A. structor). Some kinds feed exclusively on aphides (L. flavus, L. brunneus), or nearly exclusively (L. niger, Camponotus). Others know how to vary their means of subsistence, to lick flowers, to kill insects, to rear aphides; such are all the species of the genus Formica. The genus Lasius exhibits great variety in this point of view. The species flavus and umbratus rear only the aphides of roots [aphis radicum?]. L. fuliginosus only pays attention to the aphides of the bark of trees; L. niger and alienus those of bark and the outer part of plants. They also know how to transport these latter from one place to another. In fine, L. emarginatus only takes a few of the aphides, and only those found on the surface of plants.' (Forel, p. 421.)

M. Forel, like Huber, has never seen an ant kill or injure an aphis. M. Duveau, on the contrary, has seen an ant in the act of tearing and devouring an aphis; but such conduct on the part of an ant is probably quite exceptional.

Leaving the subject of ants and their milking cows, we need

do little more than refer to that of various other insects being often found in ants' nests. We learn from Dr. T. A. Power (Smith's Catalogue of British Formicidæ,' p. 223), who has collected these ants'-nest-insects for several years, that in the nest of Formica rufa he has found no less than sixteen beetles and the larvæ of three other kinds; five are enumerated as occurring in the nest of F. fusca, fourteen in that of F. fuliginosa, two in the nest of F. flava, one in that of F. sanguinea, one in that of Myrmica rubra, and that one species occurs in the nests of all the ants. From the habit of these various beetles being found in ants' nests the name of Myrmecophilous beetles has been given to them. There is some difference of opinion as to the cause of the presence of these beetles in the abodes of ants. Is there in this case also, as in the aphides and gall-insects, a mutual interchange of benefit conferred, or is their presence merely accidental? We do not know. Forel is of the latter opinion, considering that the beetles are as parasites in the nests; other observers, as Lespès and Müller, consider that some of the beetles, as Claviger and Lomechusa, are nourished by the ants, which disgorge honied sweets for them; that in return for this act of kindness the ants lick the wing-cases of Claviger and the abdomen of Lomechusa (!) M. Forel seems evidently sceptical as to this explanation. We have often found various beetles in the nests of ants, but are quite unable to throw any light as to the cause of their presence there, which we are inclined to think is more accidental than designed. We, therefore, pass over this question, and approach another, which has long been one more or less disputed in the natural history of ants. Do ants lay up in the summer food for winter's consumption? At one time the answer was unhesitatingly given in the affirmative as true of all ants, or, at least, of the family in general; now it has been as strongly denied of any kind of ant; now, again, whilst the general negative is allowed to be the case, it has been affirmed to be partially correct. What the opinion of the Jews of Palestine was one cannot definitely say; the oft-quoted passage in the Bible, Go to the ant, thou sluggard: consider her ways and be wise; which, having no guide, overseer, or ruler, provideth her meat in the summer, and gathereth her food in the harvest' (Prov. vi. 6-8; see also xxx. 25), has been generally supposed to imply that the Jews held that the ant lays up store of food in summer or autumn for winter's consumption, but the words do not really prove anything of the kind. Kirby and Spence have well said of these words:'If they are properly considered it will be found that the interpreta

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tion which seems to favour the ancient error respecting ants, has been fathered upon them, rather than fairly deduced from them. He does not affirm that the ant, which he proposes to the sluggard as an example, laid up in her magazine stores of grain against winter, but that with considerable prudence and foresight she makes use of proper seasons to collect a supply of provisions for her purposes. There is not a word in them implying that she stores up grain or other provisions. She prepares her bread and gathers her food, namely, such food as is suited to her, in summer and harvest, that is when it is most plentiful; and thus shows her wisdom and prudence by using the advantages offered to her.' (Introd. to Entom., vol. ii. p. 47.)

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The author of the passage in the Proverbs' is speaking against idleness-against the sluggard,' who 'sleepeth in harvest and causeth shame' (x. 5); that is, who neglects proper and seasonable times, and sleeps when he ought to be working. Give not sleep to thine eyes nor slumber to thine eyelids' (vi. 4). The sluggard will not plow; . . . therefore 'shall he beg in harvest and have nothing' (xx. 4). He aptly refers for a lesson in diligence to one of the most active and busy of all creatures, the little ant, which always avails herself of favourable opportunities-which does not sleep in harvest, but gathers food at the right time. The text in the original Hebrew implies no storing properties for winter use; the word (takin), means simply she establisheth, or collecteth;' and (âgerah) she scrapeth together, or provideth.' The Hebrew verbs are synonymous; and the sentences she pro'videth her meat in the summer,' she gathereth her food in 'the harvest,' are simply an instance of a common Hebrew parellelism. No doubt the writers in the Old and New Testaments shared the opinions current in their time, and sometimes, especially in physical matters and those relating to natural history, those opinions were erroneous; but this is no case in point.* But though there is nothing to show that the Jews believed that the ant stored up food for winter's use, it is certain that the belief was prevalent amongst ancient Greek and Roman writers, amongst Jewish rabbis and Arabian writers on natural history. Modern authors as Prior, Milton,

*The writer of the notes on the Book of Proverbs in the Speaker's Commentary' (vol. iv.), Professor Plumptre, on this passage rightly says: The point of comparison is not so much the foresight of the insect as its unwearied activity during the appointed season, rebuking 'man's inaction at the special crisis;' but we do not agree with the commentator, that in xxx. 25 the storing provident habit of the 'ant is brought under our notice.' The Hebrew verb here translated 'prepare' in our version is the same that occurs in the other passage,

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