Homes Without Hands: Being a Description of the Habitations of Animals, Classed According to Their Principle of Construction

The whole of the exterior is thickly studded with projections, varying in size and shape, but being all of some sharpness at the tip. These projections are comparatively few at the top of the nest, becoming gradually more numerous as they approach the bottom, until at last they are set so thickly that the finger can scarcely be laid between them.

The object of these projections is not ascertained. The nest always hangs very low, seldom being more than three or four feet from the ground, and some writers say that the office of the sharp projections is to guard the nest from the attacks of the felidæ and other honey and grub-loving mammalia. Such may indeed be the true explanation, and indeed it is so obvious that no one could avoid seeing it. But I very much doubt whether a far better explanation is not in store, and I can not see why the Myrapetra should stand in need of such protection, when the nest of the Nectarinia, which is placed in precisely the same conditions, is perfectly smooth and defenseless.

One use of the projections is evidently for the double purpose of concealing and protecting the entrance. On looking at the nest from above, no entrance is visible, and it is not until after a close examination that the openings are found. They are concealed under a row of the projections, which overhang them like the eaves of a house, and effectually keep off the rains which fall in such heavy torrents during tropical storms. The material of which these projections are made is the same as that of which the walls of the nest are built, except that it is very much thicker and harder, the various layers being hardly distinguishable, even with a good magnifier.

The interior of the nest is as remarkable as its exterior.

When cut open longitudinally, an operation which was carefully performed by Mr. White, a very curious sight presents itself. The nest is filled with combs, all very much curved, and these curves accommodating themselves beautifully to the general form of the nest. At the top is a nearly globular mass of brown, paper-like substance, which is apparently the nucleus of the nest. The first comb closely surrounds this globular mass, leaving only a small interval between them, so that it forms part of a hollow sphere, and a section of it would present a form like that of the capital letter C laid on its back.

The rest of the combs follow in regular order, the curve of each becoming shallower, until the last is but slightly depressed in the centre. They are carried to the sides of the nest and thereto attached, except in a few places, where an open space is left between the edge of the comb and the side of the nest, so as to allow the wasps to have access to the different tiers of cells. As is the case with most of the wasp tribe, the tiers are single, and the mouths of the combs are all downward.

The depth of the cells, and consequently the thickness of the combs, varies according to their position in the nest, the upper cells being the largest, and those below the smallest. The longest cells are from five to seven lines in length, and the shortest about two lines. The material of which they are made is the same as that of which the exterior is formed, and is of quite as dark a color. In texture, however, it is much slighter, being very thin and paper-like. These cells extend to the very edges of the combs, of which there are fourteen in the present specimen. The length of the nest is sixteen inches, and its diameter in the widest part is one foot.

In the upper combs was discovered a quantity of honey, which, when it was found, was hard and dry, of a deep brownish-red, and without either taste or scent. De Azara mentions that himself and some of his men ate the honey of the Myrapetra, and that it was of a deleterious character. Another species of honey-making wasp, Polistes Licheguana, a native of Brazil, was discovered by M. St. Hilaire, who mentions that it lays up in the nest a large provision of honey, which is very injurious to mankind, on account of the poisonous plants from which it is taken. Polistes gallica also fills its cells with honey, which, however, does not seem to be poisonous.

Within the nest were found also the remains of insects. There was the body of a black fly, which belongs or is allied to the genus Bibio, and the remains of a neuropterous insect, which apparently belongs to the genus Hemerobius.

The Myrapetra itself is of variable size, the largest being about four lines in length, and rather more than half an inch in expanse of wing. It is of a dusky brown color, and is remarkable for having the first joint of the abdomen very much lengthened and narrowed, so that it somewhat resembles the same organ in the Pelopæus.

At the left hand of the same illustration may be seen a rather large globular nest, suspended from the boughs. This nest is shown in the position which it usually occupies, namely, hidden in the dark recesses of the Brazilian forest, amid the varied vegetation which grows so profusely in the hot and wet parts of the country which the insect frequents.

The name of the species which makes this nest is Nectarinia analis, a title which is significant and appropriate enough, but which is rather unfortunate, inasmuch as it has already been applied to a genus of birds, the well-known honey-suckers of Africa and India, which are so frequently mistaken for humming-birds, on account of their small size, their brilliant plumage, their slender beaks, and their fondness for flowers.

This is not nearly so beautiful a nest as that which has just been described, the combs being devoid of regularity, and piled upon each other, as if the insect had no settled plan on which to work, and put each comb in any place where there happened to be room for it. Irregular, however, as the structure may seem, it is not without a kind of order; for though the combs look as if they had been placed in a heap, and then rolled together, so as to assume a partially spherical shape, they are at all events made with the intention of forming that shape, so that they may be included under a single covering. In the specimen in the British Museum, the outer wall of the nest has been broken away in several places, so as to permit the combs to be seen.

The entrance for the insects is very small, and when the respective dimensions of the wasp and the nest are taken into consideration, it seems really wonderful that when the inhabitants enter their house, they do not lose themselves in the intricate windings through which they pass from one comb to another. The wasp which makes this nest is bee-like in form, and very small, not a quarter of an inch in length, and bearing some resemblance to those tiny solitary bees that are seen so plentifully upon dandelions and various umbelliferous flowers.

The nest is always hung near the ground, quite as low as that of the Myrapetra, and is suspended from the slender twigs and long, delicate leaves which are woven into its substance, and in many places pierce completely through the nest, and project through the outer covering. It is, however, destitute of the sharp projections which guard the home of the latter insect, and as the outer wall is both thin and fragile, it would fall an easy prey to any insect-eating animal that might take a fancy to it. I can not but think that this utterly defenseless state of the Nectarinia's nest affords a proof that the spikes upon the habitation of the Myrapetra are not for the purpose of defending the nest against the attacks of enemies.

As is the case with the Myrapetra, the cells are made with walls much firmer than those of our English wasps or hornet, which are only intended to hold successive generations of young, and in consequence are made of a comparatively flimsy material, only strengthened very slightly at the entrance. Were honey to be placed in the cell of any known British wasp it would immediately soak into the walls of the cell, and thence escape by slow degrees; but as the young grub, which is the only tenant of the cell, is without feet and is not in the least formed for locomotion, a very slight partition is sufficient to control its movements.

The grub does nothing but hold to the end of the cell with its piercers, open its mouth for food, and occasionally protrude or withdraw itself in a very slight degree; and its utter immobility in the larval and pupal states affords a strange contrast to the restless and fussy activity which actuates it after it has attained its perfect form.

As is generally known, the nests of wild honey-bees are placed in the hollows of trees. Mr. Cotton, the well-known apiarian, remarked, when discussing the comparative merits of straw and wooden hives, that in a state of nature the bee never builds in a truss of straw, but in a hollow tree. Now, although I quite concur with that author in his partiality for the wooden hive, I can not see that the illustration which he employs has any thing to do with the subject, or that it affords the least proof on either side of the argument. Wild bees are not very likely to find trusses of straw in the woods, and those trusses conveniently hollowed to receive them. But I do think that if a few common straw hives were set in the woods, the bees would be as likely to take up their habitation in them as in the hollows of trees.

Still, among honey-bees, of which there are several species, the custom of nesting in hollow trees is almost universal. Bee-hunters, whether biped or quadruped, whether man, bird, ratel, or bear, search for their sweet spoil in the trees, and know by experience when a tree is likely to contain honey-combs. But in certain parts of tropical America the bees change their habits.

There is a genus of wild honey-bees, named Trigona, the members of which are notable for their bold departure from ordinary bee customs. They make their nests at the tops of the branches, it is true, but they do not place their combs inside the hollow trees, of which there is great store in the woods. The Trigonas make nests of a pear shape, and of tolerable size, and hang them at the very summit of trees and at the end of the slenderest twigs, so that even the agile monkeys of that land, aided with their long, prehensile tails, are unable to reach the nest.

It is somewhat remarkable that the habit of this insect should be so different from the usual custom, and the more so that a closely-allied species, inhabiting the same country, and which possibly belongs to the same genus, makes its nest in trees according to the ordinary type, and places its combs within the hollows of decaying trees. The honey of this bee is described as being very sweet and richly flavored—so richly, in fact, that very little of it can be taken.

A CREATURE is upon our list of pensile insects, which may also be reckoned among the social or parasitic insects, but which makes its habitation in such a manner that its proper place is among the pensiles. This is the pretty little ichneumon which is known to entomologists as Microgaster alvearius. The name Microgaster is of Greek origin, and signifies "little belly," this being a very appropriate name for this insect, whose abdomen is of very small dimensions, and indeed appears to be just a little supplementary growth which might be removed without causing any inconvenience to the insect. It belongs to the same genus as a very common insect called Microgaster glomeratus, which will be duly described when the parasitic animals are under consideration.