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and over them the ants watch with a wonderful care, defending them from the attacks of birds, wasps, ichneumons, and other creatures, who would rid the poor plant of its parasites. They have even been known to build galleries of clay over the surface of a pine-apple, in order to shelter the Cocci who were destroying the fruit.

Mr. Belt found that a red passion-flower, which secretes honey from glands on its young leaves and on the sepals of its flower-buds, was carefully guarded by a certain species of ant (Pheidole), who consumed the honey, and who furiously drove off all leaf-cutters and other intruders. But, after a couple of seasons, a colony of parasitical scale-insects, which secrete honey, established themselves upon the passion-flower, to its great injury. The ants transferred their care and attention to these, and, from the guardians of the plant, became indirectly, but not the less substantially, its enemies. This is a striking proof of the untrustworthy character of our insect—or, more generally speaking, of our animal—allies. At one moment they may be defending our property from depredation, but on a slight change of circumstances their interests may cease to coincide with our own, and they may go over to our enemies. The question what animal species we ought to protect and which to destroy, and how far we ought to go in each case, becomes, on closer inspection, exceedingly complicated.

As an example of an omnivorous ant, we may take the "fire-ant" of the Amazon, of which Mr. Bates gives us a striking account:[1] "Aveyros may be called the headquarters of the fire-ant, which might be fittingly termed the scourge of this fine river. It is found only on sandy soils, in open places, and seems to thrive more in the neighborhood of houses and weedy villages, such as Aveyros; it does not occur at all in the shades of the forest. Aveyros was deserted a few years before my visit on account of this little tormentor, and the inhabitants had only recently returned to their houses, thinking its numbers had decreased. It is a small species, of a shining reddish color, not greatly differing from the common stinging ant of our own country (Myrmica rubra), except that the pain and irritation caused by its sting are much greater. The soil of the whole village is undermined by it; the ground is perforated with the entrances to their subterranean galleries, and a little sandy dome occurs here and there, where the insects bring their young to receive warmth near the surface. The houses are overrun with them; they dispute every fragment of food with the inhabitants, and destroy clothing for the sake of the starch. All eatables are obliged to be suspended in baskets from the rafters, and the cords well soaked with copaiba-balsam, which is the only means known of preventing them from climbing. They seem to attack persons out of sheer malice. If we stood for a few moments in the street, even at a distance from their nests, we

  1. "Naturalist on the River Amazon."