Formic acid is known to have considerable antiseptic properties. Chemical tests show its presence in well-ripened honey, but not in freshly gathered nectar. The natural conclusion is that it has been added by the bees to assist in the preservation of the honey. In what manner it is supplied has frequently been questioned. Tests applied to the blood of the bee show its presence there, and the secretions of the head glands show still larger quantities. It is therefore reasonable to suppose that these glands, as well as the poison glands themselves secrete formic acid, and that the honey receives its portion from the former, the head glands, upon being disgorged from the honey-sac or during the manipulation to which it is subjected in the hive.
WATER.
During cold or cool weather much condensation of moisture takes place in wooden hives as these are usually arranged. The water, collecting in drops on the interior walls of the hive and on the cold, sealed honey, often trickles down over the cluster of bees, to their great injury. It has been claimed that when brood rearing begins this condensed moisture will be utilized in the preparation of brood food. Very possibly it may, yet its use is probably detrimental, since it is charged with waste products of the hive—those of respiration, etc. In its absence the water contained in the honey, if the latter has not granulated, seems to be sufficient. Later, however, when no condensation takes place in the hive and the greater number of developing larvæ require considerable supplies of water in their food, special trips are made to brooks and pools for it, and dew is often gathered from leaves.
SILK.
The larval bee produces a small amount of silk from glands in its head. The pupal cell is partially lined with this. Later, as the bee develops, there being no further use for the glands, they become atrophied.
WAX.
The light colored pellets which are carried into the hive on the hind legs of the workers, and which have been described as pollen, are often mistaken for wax. The fact is, wax is not gathered in the form in which we see it, except in rare instances, when, bits of comb having been left about, small quantities will be loaded up and taken in as pellets on the legs. Ordinarily it comes into the hive in the shape of honey and is transformed by the workers within their own bodies into wax. This production is wholly confined to the workers, for although the queen has wax plates 011 the underside of the abdomen and wax glands beneath them, yet both are less developed than in the workers and are never used. The wax plates of the worker overlying the secreting glands are well shown in [fig. 9], those of the queen and of the related genera, Bombus and Melipona, being shown for comparison. During wax secretion, that is, when combs are being built or honey cells sealed over, a high temperature is maintained in the hive, and many workers may be seen to have small scales of wax protruding from between the segments of the abdomen on the underside. The molds or plates, eight in number, in which the scales appear are concealed by the overlapping of the abdominal segments, but when exposed to view ([fig. 9, a]) are seen to be five-sided depressions lined with a transparent membrane. The wax glands themselves are beneath this membrane, and through it the wax comes in a liquid form. As the scales harden they are pushed out by the addition of wax beneath. The bees pluck them out with neat pincers ([fig. 7, a and b]) formed by the articulation of the hind tibiæ with the adjacent tarsal joints, pass them forward to the mandibles, and mold them into the shape of hexagonal cells, meanwhile warming and moistening them with the secretions of the head glands to render the wax more pliable.
Fig. 9.—Wax disks of social bees: a, Apis mellifera worker; b. A. mellifera queen; c, Melipona worker; d, Bombus worker—all enlarged. (From Insect Life.)