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fork, and with them also smooth surfaced masses of a species of Hydnophytum.' There
course, many cases in which the action of ants is very beneficial to plants. They kill off a great number of small caterpillars and other insects. Forel found in one large nest that more than twentyeight dead insects were brought in per minute; which would give during the period of greatest energy more than 100,000 insects destroyed in a day by the inhabitants of one nest alone.
Our English hunting ants generally forage alone, but in warmer countries they hunt in packs, or even troops.
As already mentioned, none of our northern ants store up grain, and hence there has been much discussion as to the well-known passage of Solomon. I have indeed observed that the small brown ants, Lasius niger, sometimes carry seeds of the violet into their nests, but for what purpose is not clear. It is, however, now a well-established fact that more than one species of southern ants do collect seeds of various kinds. The fact, of course, has long been known in those regions.
Indeed, the quantity of grain thus stored up is sometimes so considerable, that in the Mischna,' rules are laid down with reference to it; and various commentators, including the celebrated Maimonides, have discussed at length the question whether such grain belonged to the owner of the land, or might be taken
by gleaners-giving the latter the benefit of the doubt. They do not appear to have considered the rights of the ants.
Hope' has called attention to the fact that Meer Hassan Ali, in his History of the Mussulmans, expressly mentions it. More industrious little creatures,' he says, 'cannot exist than the small red ants, which are so abundant in India. I have watched them at their labours for hours, without tiring. They are so small, that from eight to twelve in number labour with great difficulty to convey a grain of wheat or barley, yet these are not more than half the size of a grain of English wheat. I have known them to carry one of these grains to their nest, at a distance from 600 to 1,000 yards. They travel in two distinct lines over rough or smooth ground, as it may happen, even up and down steps, at one regular pace. The returning unladen ants invariably salute the burthened ones, who are making their way to the general storehouse; but it is done so promptly, that the line is neither broken nor their progress impeded by the salutation.'
Sykes, in his account of an Indian ant, Pheidole providens, appears to have been the first of modern scientific authors to confirm the statements of Solomon. He states that the above-named species collects large stores of grass seeds, on which it subsists from February
i Trans. Ent. Soc. 1840, p. 213.
? Ibid. 1836, p. 99. Dr. Lincecum has also made a similar observation.
to October On one occasion he even observed the ants bringing up their stores of grain to dry them after the closing thunderstorms of the monsoon ; an observation which has been since confirmed by other naturalists.
It is now known that harvesting ants occur in the warmer part of Europe, where their habits have been observed with care, especially by Moggridge and Lespès. It does not yet seem quite clear in what manner the ants prevent the grains from germinating. Moggridge found that if the ants were prevented from entering the granaries, the seeds began to sprout, and that this was also the case in deserted granaries. It would appear therefore that the power of germination was not destroyed.
On the other hand, Lespès confirms the statement long ago made by Aldrovandus that the ants gnaw off the radicle, while Forel asserts that Atta structor allows the seeds in its granaries to commence the process of germination for the sake of the sugar.
A Texan ant, Pogonomyrmex barbatus, is also a harvesting species, storing up especially the grains of Aristida oligantha, the so-called "ant rice,' and of a grass, Buchloe dactyloides. These ants clear disks, ten
, or twelve feet in diameter, round the entrance to their nest, a work of no small labour in the rich soil, and under the hot sun, of Texas. I say 'clear disks, but some, though not all, of these disks are occupied, especially round the edge, by a growth of ant rice. These
ants were first noticed by Mr. Buckley,' and their habits were some time afterwards described in more detail by Dr. Lincecum,” who maintained not only that the ground was carefully cleared of all other species of plants, but that this grass was intentionally cultivated by the ants. Mr. McCook, by whom this subject has been recently studied, fully confirms Dr. Lincecum that the disks are kept carefully clean, that the ant rice alone is permitted to grow on them, and that the produce of this crop is carefully harvested; but he thinks that the ant rice sows itself, and is not actually cultivated by the ants. I have myself observed in Algeria, that certain species of plants are allowed by the ants to grow on their nests.
· Proc. Acad. Nat. Sci. Philadelphia, 1860.
ON THE RELATIONS OF ANTS TO. OTHER ANIMALS.
The relations existing between ants and otheranimals are even more interesting than their relations with plants. As a general rule, not, however, without many remarkable exceptions, they may be said to be those of deadly hostility.
Though honey is the principal food of my ants, they are very fond of meat, and in their wild state ants destroy large numbers of other insects. Our English ants generally go out hunting 'alone, but many of the species living in hotter climates hunt in packs, or even in troops.
Savage has given a graphic account of the “Driver' ants (Anomma arcens, West.) of West Africa. They keep down, he says, “the more rapid increase of noxious insects and smaller reptiles ; consume much dead animal matter, which is constantly occurring, decaying, becoming offensive, and thus vitiating the atmosphere, and which is by no means the least important in the Torrid Zone, often compelling the inhabitants to keep
1.On the Habits of the Driver Ants,' Trans. Ent. Soc. 1847