successive sheets of silk which cover the nest, and which inclose layers of air between them, form a protection which is far warmer than would be obtained by a solid mass of silk measuring twice the thickness of the three walls, together with their intervening

spaces.

THERE is an allied insect, popularly called the BROWN-TAILED MOTH (Porthesia auriflua), which spins a social nest that in many respects resembles that of the Gold-tailed Moth. The nest, however, is scarcely so elegant, nor is the silken web so beautifully delicate. Much, however, depends upon surrounding conditions, such as the disposition of the twig on which the nest is placed, and the presence or absence of leaves, whether those of the tree or of other plants that happen to grow in close proximity.

THESE nests are very firmly constructed, and the walls are solid, as is needful for insects which are obliged to pass the winter within them. There are, however, many caterpillars which live socially, and which spin a common habitation, but which leave it before the cold weather comes on, and, in consequence, do not need such thick walls. Any hedgerows where nettles are found will supply numerous examples of such nests, made by the curious caterpillars which afterwards assume the lovely and familiar forms of the PEACOCK and SMALL TORTOISESHELL BUTTERFLIES (Vanessa Io and Vanessa urtica). Great black masses of these caterpillars may be seen upon the nettles, and, on examining them closely, they will be seen to reside within a common home, made of tough silken threads, very loosely spun, and forming a kind of net, with long and irregular meshes.

CHAPTER XXIV.

SOCIAL INSECTS CONTINUED.

A curious Ant from India (Myrmica Kirbii)—Locality of its nest-Description of the nest, its material and mode of structure-A nocturnal misadventureThe DRIVER ANT of Africa-Description of the insect-Reason for its name— Its general habits-Destructive powers of the Driver Ant-How the insects devour meat and convey it home-How they kill snakes-Native legend of the python-Their mode of march-Fatal effects of the sunbeams-An extemporised arch-Method of escaping from floods-Site of their habitation-Modes of destroying them-Living ladders and their structure-Method of crossing streams-Tenacity of life-A decapitated Ant-Mode of biting-Description of the insect-Curious nest of a Brazilian Wasp-Weight of the nest and method of attachment-Variety of Polistes nest-Polistes aterrimus and its singular nest-Beautiful structure of an unknown Polistes.

ALTHOUGH several species of Ants have been mentioned under the title of burrowing insects, there are many which possess very interesting habits, and which may here take their place among the creatures which build social habitations. Among them is a curious insect inhabiting India, and discovered by Colonel Sykes, the well-known naturalist, who called it Myrmica Kirbii.

This insect forms its nest on the branches of trees and shrubs, and Colonel Sykes mentions that he has found their curious habitation on the branches of the Kurwund shrub, Carissa Carandas, and on the Mango-tree, Mangifera Indica.

The nests are more or less spherical, and are about as large as an ordinary foot-ball. The material of which they are made is cow-dung, which is spread in flakes in a manner that reminds the observer of the outside cover of a wasp's nest. The flakes are placed upon each other like the tiles of a house, so that although the insects can creep into the nest beneath the flakes, no water can enter. On the summit of the nest is one very large flake, that acts as a general roof to the structure.

Within the nest are placed a number of cells made of the same material as the exterior, and in them may be found insects in every state of development, eggs in one, larvæ in another, and

pupa in a third. No provision seems to be laid up within the nest, so that the inhabitants must depend on their daily excursions for their food.

When Colonel Sykes brought home the first nest he discovered, he hung it to the tent-pole, preparatory to examining it in the morning. "In the night the men were awakened by repeated punctures and general irritation of the skin, but the darkness prevented them from discovering their tormentors, and they continued to toss and tumble in their beds for some hours in no very complacent state of mind. At last they got up, dressed themselves, and abandoned the tent; but the evil was rather aggravated than abated, as parts of their persons which had previously escaped had now their share of suffering. At daylight they discovered to their consternation that they were covered with minute ants, which had filled their pantaloons, penetrated the sleeves of their coats and every other part of their habiliments. On inspecting the tent, they found the interior teeming with multitudes of little angry beings, in busy progress, seeking to resent the outrage which had been committed on the community by the removal of their abode."

The insects are extremely small, barely one fifth of an inch in length, and are reddish in colour.

PERHAPS one of the most terrible of insects is that which is appropriately called the DRIVER ANT of Western Africa (Anomma arcens).

This insect is a truly remarkable creature. Although it is to be found in vast numbers, it has never been found in the winged condition, and neither the male nor the female have as yet been discovered. The workers are uniform in colour, but exceedingly variable in size. Their hue is deep brownish black, and their length varies from half an inch to one line, so that the largest workers nearly equal the common earwig, while the smallest are no larger than the familiar red ant of our gardens. In the British Museum are specimens of the workers, which form a regular gradation of size, from the largest to the smallest.

They are called Driver Ants, because they drive before them every living creature. There is not an animal that can withstand the Driver Ants. In their march, they carry destruction before them, and every beast knows instinctively that it must not cross

their track. They have been known to destroy even the agile monkey, when their swarming host had once made a lodgment on its body, and when they enter a pigstye, they soon kill the imprisoned inhabitants, whose tough hides cannot protect them from the teeth of the Driver Ants. Fowls they destroy in numbers, killing in a single night all the inhabitants of the henroost, and having destroyed them, have a curious method of devouring them.

The Rev. Dr. Savage, who has experimented upon these formidable insects, killed a fowl and gave it to the Ants. At first, they did not seem to pay much attention to it, but he soon found that they were in reality making their preparations. Large parties of the insects were detached for the purpose of preparing

a road, and worked with the assiduity which seems to be a characteristic of these energetic insects. Numbers of them were employed in smoothing the road to the nest by removing every obstacle out of the way, until by degrees a tolerably level road was obtained. The Ants are possessed of strength which seems gigantic when compared with their size, carrying away sticks four or five times as large as themselves, and never failing to pounce upon any grub or insect that might happen to be lurking beneath their shelter. They always carried such burdens longitudinally, grasping them with their jaws and legs, and passing the load under the body. Some of these roads are more than two hundred yards in length.

Meanwhile, the other Ants were busy with the fowl. Beginning at the base of the beak, they contrived to pull out the feathers one by one, until they stripped it regularly backwards, working over the head, along the neck, and so on to the body. This was evidently a very hard task, as the insects did not possess sufficient strength to pull out the feathers by main force, and were consequently obliged to grub them up laboriously by the roots. The next business was to pull the bird to pieces, and at this work they were left. Unfortunately the experiment was spoiled by the natives, who stole the fowl, thinking that the Ants had eaten so many of their poultry that they were justified in retaliation. Others chose to excuse themselves by saying that they thought the fowl to be a fetish offering to the Ants, and accordingly took it away from them.

The large iguana lizards fall victims to the Driver Ants, and so do all reptiles, not excluding snakes. It seems, from the personal observations of Dr. Savage, that the Ants commence their attack on the snake by biting its eyes, and so blinding the poor reptile, which only flounders and writhes helplessly on one spot, instead of gliding away to a distance.

It is said by the natives, that when the great python has crushed its prey in its terrible folds, it does not devour it at once, but makes a large circuit, at least a mile in diameter, in order to see whether an army of Driver Ants is on the march. If so, it glides off, and abandons its prey, which will soon be devoured by the Ants; but if the ground is clear, it returns to the crushed animal, swallows it, and gives itself to repose until the process of digestion be completed. Whether this assertion

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