The man shrank back behind the nest, but his imprudent movement brought its own punishment.

Knowing that the ascent of the tree was impossible, and at the same time unwilling to leave its prey, the lion sat down at the foot of the tree, and kept watch upon the man. Hour after hour the lion mounted guard over its prisoner, until thirst overpowered hunger, and the animal was forced reluctantly to quit its post and seek for water. The man then scrambled down the tree, and made the best of his way homeward, little the worse for his imprisonment except the fright, and a skin scorched by long exposure to the sun. The artist has introduced this little episode into the illustration, because it enables the reader to judge of the enormous size of the nest.

Season after season the Weaver Birds continue to add their nests, until at last the branch is unable to endure the weight, and comes crashing to the ground. This accident does not often occur during the breeding months, but mostly takes place during the rainy season, the dried grass absorbing so much moisture that the weight becomes too great for the branch to bear.

The nest group which is shown in the illustration is of medium size, as can be ascertained by its shape. In its early state, the nest-mass is comparatively long and narrow, spreading out by degrees as the number of nests increases, so that at last it is as wide and as shallow as an extended umbrella. The dimensions of some of these structures may be gathered from the fact that Le Vaillant counted in one unfinished edifice, besides the deserted nests of previous seasons, no less than three hundred and twenty nests, each of which was occupied by a pair of birds engaged in bringing up a brood of young, four or five in number.

Those who are acquainted with Borneo and the customs of its inhabitants can not fail to perceive the analogy between these social nests of the Weaver Bird and the "long houses" of the Dyaks, each of which houses is in fact one entire village, sheltering a whole community under a single roof.

The Weaver Birds have but few enemies. First, there are the snakes, which are such determined robbers of nests, swallowing both eggs and young; and then there are the monkeys, which are capable of sad depredations whenever they can find an opportunity. Monkeys are extremely fond of eggs, and there is scarcely a better bribe to a monkey, ape, or baboon, than a fresh raw egg. The bird which laid it is almost as great a dainty, and

a monkey seems to be in the height of enjoyment if a newlykilled bird be put into its paws. It always begins by eating the brain, and then tears the carcass to pieces with great deliberation. A mouse is quite as much appreciated as a bird, provided that it has been recently killed, and that the blood has not congealed.

However, the structure of the nest forms an insurmountable barrier to the snake, and the monkey can only reach a few of the cells which are near the edge. The worst enemies are certain little parrakeets, which are delighted to be able to procure nests without the trouble of building them, and which are apt to take possession of the cells and oust the rightful owners.

CHAPTER XXIII.

SOCIAL INSECTS.

Arrangement of Groups.-Nests of POLYBIA.-Curious Method of Enlargement.— Structure of the Nests.-How concealed.-Various Modes of Attachment.-A curious Specimen.-The HIVE-BEE, and its claims to Notice.-General History of the Hive.-Form of the Cells.-The royal Cell, its Structure and Use.-Uses of the ordinary Cells.-Structure of the Bee-cell.-Economy of Space.-How produced. Theories of different Mathematicians.-Measurement of Angles.-A logarithmic Table corrected by the Bee-cell.-The "Lozenge" a key to the Cell.How to form it.-Beautiful mathematic Proportions of the Lozenge.—Method of Making the Cell or a Model.-Conjectured Analogy between the Cell and certain Crystals. Effect of the Cell upon Honey.-The HORNET and its Nest.-Its favorite Localities.-Difficulties of taking a Hornet's Nest.-Habits of the Insect.— Mr. Stone's Method of taking the Nest.-The SYNCCA and its Habitation.-Beautiful Nests in the British Museum.-Description of the Insect.—Nest of the EUCHEIRA.—Its external Form.-Curious Discovery in Dissection.-A suspended Colony.-Conjectures respecting the Structure.-Nest from the Oxford Museum. -Remarkable Form of its Doors, and Material of which it is made.-The SMALL ERMINE MOTH and its Ravages.-Its large social Habitation.-General Habits of the Larva.-Why the Sparrow does not eat them.-The GOLD-TAILED MOTH and its beautiful social Nest.—Description of a Specimen from Wiltshire.—Illustration of the Theory of Heat.-The BROWN-TAILED MOTH and its Nest.-Social Habitations of the PEACH and SMALL TORTOISE-Shell Butterflies.

AFTER the Social Birds come the SOCIAL INSECTS, to which the following chapter is dedicated.

The reader will probably have noticed that several insects, especially those of the hymenopterous order, seem to have been omitted in previous chapters, although they might fairly claim admission into the ranks of Builders, Pensiles, Burrowers, and Subaquatics. The fact is, that some of them unite the characteristics

of several groups, and may therefore be placed in either of them. For example, the South American wasp, which makes the nest called popularly the "Dutchman's pipe," may be ranked either as a builder, a pensile, or a social insect. In such cases, therefore, I have endeavored to select that characteristic which seems to be marked most strongly, and have arranged the insects accordingly.

Just as the hymenoptera are chief among the pensiles and the builders, so are they chief among the Social Insects, and the species which may be placed in this group are so numerous, that it will only be possible to make a selection of a few, which seem more interesting than the others.

IN the British Museum there are some very remarkable nests made by hymenopterous insects belonging to the genus Polybia, several of which are drawn in the accompanying illustration. As

it was desirable to include more than one specimen, the figures are necessarily much reduced in size. Neither the nests nor the insects, however, are of large dimensions, and the former are so sombre in color as well as small in size that they would not of themselves attract any attention. Their nests, however, are extremely interesting, as may be seen from the examples which are figured in the illustration.

On the left hand may be seen a nearly spherical nest, which is evidently hollow, and has cells both on the outside and within the cover. These cells are not placed vertically, with their mouths downward, like those of the wasp and hornet, nor horizontally like those of the bee, but are set with their mouths radiating from the centre of the nest. Moreover, there is another curious circumstance connected with the nest. If it were to be opened, it would be seen to be composed of several concentric layers, very much like those ivory puzzle-balls which the Chinese make so beautifully.

The method by which the nest is formed is very simple, though not one that is usually seen among the hymenoptera. The layers of combs are made like hollow spheres, the mouths of the cells being outward, and, as soon as a layer is completed, the insects protect it from the weather by a cover of the same material as is used for the construction of the cells. When they require to make a fresh layer of cells, they do not enlarge the cover, as is the case with the wasp and hornet, but place the new cells upon the surface of the cover, and make a fresh cover as soon as the comb is completed. Thus the nest increases by the addition of concentric layers, composed alternately of comb and cover.

In the nest which is in the British Museum, the insects have commenced several patches of comb on the outside of the cover, and one such patch is shown in the illustration.

On the right of the globular nest is another curious structure, also made by insects of the same genus, and having a kind of similarity in its aspect. This nest, however, is very much longer in proportion to its width, and being fixed throughout its length to a leaf, is not so plainly visible as the last mentioned specimen. Indeed, when the leaf has withered, as is the case with the object from which the drawing was made, the dull brown of the nest coincides so completely with the color of the faded leaf that many persons would overlook it unless their attention were specially drawn toward it.

On the extreme right of the illustration, and in the upper cor. ner, is seen a nest which is also the work of insects belonging to the genus Polybia, and it is pendent from a bough, like the habitation of the Chartergus and other pensile hymenoptera.

In the same collection there are many more specimens of social nests formed by insects belonging to this genus, two cases being quite filled with them. One is attached to the bark of a tree, and resembles it so closely that it seems to be made of the same substance, this similarity of aspect being evidently intended as a preservative against the attacks of birds and other insect-loving creatures, which would break up the nest, and eat the immature and tender grubs. Most of the nests are fixed to leaves, and are different forms, according to the species which made them. They are mostly fixed to the under sides of the leaf, so that the weight causes the leaf to bend and to form a natural roof above them. The shape of the nest seems to depend much on the character of the plant to which it is fixed. Those that are fastened to reeds are long and slender, and generally much narrower than the sword-shaped leaf on which they rest. Others, which are fastened to short and broad leaves, adapt themselves so closely to the shape of the leaf, that, if removed, they would enable any one to conjecture the form of the leaf upon which they had been fixed.

One such nest is very remarkable. In general form it bears a singular resemblance to the nest of the fairy martin, which is figured at page 330, though its materials are entirely different. The nest is flask-shaped, and its base is fastened to a leaf which it almost covers. The body of the nest is oval, and the entrance, which is small, is placed at the end of a well-marked neck. The shell of the nest is extremely thin, not in the least like the loose, papery structure of an ordinary wasp-nest, nor the pasteboard-like material which defends the nest of the Chartergus. It is rather fragile, and in thickness is almost double that of the paper on which this account is printed.

The name of the species which builds this curious nest is Polybia sedula, and the specimen was brought from Brazil.

FOR the reasons which have been given at the beginning of this chapter, the HIVE-BEE has been reckoned among the Social Insects.

The Bee has always been one of the most interesting insects to mankind on account of the direct benefit which it confers upon