The egg.—All the eggs of the community are laid by the queen. The cells in which they are deposited vary in size and in shape, according to whether queens, drones, or workers are to be developed in them. In length the eggs are about one-twelfth of an inch; in shape, oblong, but a little broader at the upper than at the lower end, and slightly curved; in colour they are white, with a bluish tinge. Their external coat is slightly glutinous when they are first laid, and thus they adhere to the bottom of the cell in which they are deposited.
Fig. 1.—Egg's and Larva of Bees.
The larva.—Under the genial influence of the heat of the hive, ranging from 66° to 70° Fahr., the formation of the larva from the egg-contents immediately begins; and, in the course of three days, a tiny worm or grub has been developed, and makes its way out of its delicate shell. It now lies curled round, still at the base of its dwelling, and, fed by the nurse-bees on a jelly-like mixture of pollen and honey, it rapidly grows. Its food supply is made strictly correspondent to its wants, and by the time the larva is ready for its next change not a drop of the jelly is unconsumed. The fleshy white grub is in shape at first slightly, and afterwards strongly curved, and a little pointed at each end. The future segments of the insect now become gradually visible, fifteen in number, and ten of them are furnished each with a minute aperture on opposite sides of the body, and connected with air-tubes, or spiracles, by which respiration is carried on. The segments have also a series of minute tubercles, whose office seems to be to aid in the motions of the grub, which motions doubtless contribute to the assimilation of food, and so to growth. The head of the larva is small, is smooth above, and is furnished with two little projecting horns, from which will be developed the future antennæ.
Fig. 2.—Larvæ.
a. Worker larvæ. b. Queen larva. c. Queen cell sealed.
The jaws are small, and articulate below a narrow lip. They are constantly in motion, probably to reduce the pollen-grains existing in the so-called bee-bread, which, with honey, as already mentioned, constitute their food. Beneath the jaws, and centrally between them, is a fleshy protuberance, which has a perforation at its extremity, through which the larva emits a sticky fluid, similar to that from which spider's-web or silk is made. With this the grub spins for itself a cocoon, in which a further and important transformation takes place in the structure of the insect.
Fig. 3.—Sealed Cells.
The time occupied in making this silken dress is, for drone- and worker-larvæ, thirty-six hours. Princesses, who trouble themselves to make only half-cocoons, finish theirs in twenty-four hours. So soon as the grubs are ready for this process, the nurse-bees form over the entrance to each cell a lid made of wax and a sticky substance called propolis; leaving, however, minute perforations for the admission of air. These coverings are darker than the caps of the honey-cells. They are also somewhat convex over worker-larvæ, and over drone-grubs they stand out almost hemispherically. Hence it is easy to distinguish the look of brood cells from that of those containing food-stores. Moreover, the former are situated usually in or near the centre of each comb, while the latter, where the two co-exist, are found near the top. It is very important to learn the difference in appearance between the two, as several points of successful manipulation depend upon the knowledge.