Insect Architecture

by James Rennie

When they have in this manner worked the bottoms of the first row of cells into the required forms, some of the nurse-bees finish them by imparting a sort of polish, while others proceed to cut out the rudiments of a second row from a fresh wall of wax which has been built in the meanwhile by the wax-workers, and also on the opposite side of this wall; for a comb of cells is always double, being arranged in two layers, placed end to end. The cells of this second row are engrafted on the borders of cavities hollowed out in the wall, being founded by the nurse-bees, bringing the contour of all the bottoms, which is at first unequal, to the same level; and this level is kept uniform in the margins of the cells till they are completed. At first sight nothing appears more simple than adding wax to the margins; but from the inequalities occasioned by the shape of the bottom, the bees must accumulate wax on the depressions, in order to bring them to a level. It follows accordingly that the surface of a new comb is not quite flat, there being a progressive slope produced as the work proceeds, and the comb being therefore in the form of a lens, the thickness decreasing towards the edge, and the last-formed cells being shallower or shorter than those preceding them. So long as there is room for the enlargement of the comb, this thinning of its edge may be remarked; but as soon as the space within the hive prevents its enlargement, the cells are made equal, and two flat and level surfaces are produced.

M. Huber observed, that while sketching the bottom of a cell, before there was any upright margin on the reverse, their pressure on the still soft and flexible wax gave rise to a projection, which sometimes caused a breach of the partition. This, however, was soon repaired, but a slight prominence always remained on the opposite surface, to the right and left of which they placed themselves to begin a new excavation; and they heaped up part of the materials between the two flutings formed by their labour. The ridge thus formed becomes a guide to the direction which the bees are to follow for their vertical furrow of the front cell.

We have already seen that the first cell determines the place of all that succeed it, and two of these are never, in ordinary circumstances, begun in different parts of the hive at the same time, as is alleged by some early writers. When some rows of cells, however, have been completed in the first comb, two other foundation-walls are begun, one on each side of it, at the exact distance of one-third of an inch, which is sufficient to allow two bees employed on the opposite cells to pass each other without jostling. These new walls are also parallel to the former; and two more are afterwards begun exterior to the second, and at the same parallel distance. The combs are uniformly enlarged, and lengthened in a progression proportioned to the priority of their origin; the middle comb being always advanced beyond the two adjoining ones by several rows of cells, and these again beyond the ones exterior to them. Did the bees lay the foundations of all their combs at the same time, they would not find it easy to preserve parallelism and an equality in their distances. It may be remarked further, that beside the vacancies of half an inch between the cells, which form what we call the highways of the community, the combs are pierced in several places with holes which serve as postern-gates for easy communication from one to another, to prevent loss of time in going round. The equal distance between the combs is of more importance to the welfare of the hive than might at first appear; for were they too distant, the bees would be so scattered and dispersed, that they could not reciprocally communicate the heat indispensable for hatching the eggs and rearing the young. If the combs, on the other hand, were closer, the bees could not traverse the intervals with the freedom necessary to facilitate the work of the hive. On the approach of winter, they sometimes elongate the cells which contain honey, and thus contract the intervals between the combs. But this expedient is in preparation for a season when it is important to have copious magazines, and when, their activity being relaxed, it is unnecessary for their communications to be so spacious and free. On the return of spring, the bees hasten to contract the elongated cells, that they may become fit for receiving the eggs which the queen is about to deposit, and in this manner they re-establish the regular distance.[AS]

We are indebted to the late Dr. Barclay of Edinburgh, well known as an excellent anatomist, for the discovery that each cell in a honeycomb is not simply composed of one wall, but consists of two. We shall give the account of his discovery in his own words:—

"Having inquired of several naturalists whether or not they knew any author who had mentioned that the partitions between the cells of the honeycomb were double, and whether or not they had ever remarked such a structure themselves, and they having answered in the negative, I now take the liberty of presenting to the Society pieces of honeycomb, in which the young bees had been reared, upon breaking which, it will be clearly seen that the partitions between different cells, at the sides and the base, are all double; or, in other words, that each cell is a distinct, separate, and in some measure an independent structure, agglutinated only to the neighbouring cells; and that when the agglutinating substance is destroyed, each cell may be entirely separated from the rest.

“I have also some specimens of the cells formed by wasps, which show that the partitions between them are also double, and that the agglutinating substance between them is more easily destroyed than that between the cells of the bee.”[AT]

Irregularities in their Workmanship.

Though bees, however, work with great uniformity when circumstances favour their operations, they may be compelled to vary their proceedings. M. Huber made several ingenious experiments of this kind. The following, mentioned by Dr. Bevan, was accidental, and occurred to his friend Mr. Walond. "Inspecting his bee-boxes at the end of October, 1817, he perceived that a centre comb, burthened with honey, had separated from its attachments, and was leaning against another comb so as to prevent the passage of the bees between them. This accident excited great activity in the colony; but its nature could not be ascertained at the time. At the end of a week, the weather being cold, and the bees clustered together Mr. Walond observed, through the window of the box, that they had constructed two horizontal pillars betwixt the combs alluded to, and had removed so much of the honey and wax from the top of each as to allow the passage of a bee: in about ten days more there was an uninterrupted thoroughfare; the detached comb at its upper part had been secured by a strong barrier, and fastened to the window with the spare wax. This being accomplished, the bees removed the horizontal pillars first constructed, as being of no further use."[AU]

A similar anecdote is told by M. Huber. “During the winter,” says he, "a comb in one of my bell-glass hives, having been originally insecure, fell down, but preserved its position parallel to the rest. The bees were unable to fill up the vacuity left above it, because they do not build combs of old wax, and none new could be then obtained. At a more favourable season they would have engrafted a new comb on the old one; but now their provision of honey could not be spared for the elaboration of this substance, which induced them to insure the stability of the comb by another process.