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27. Characteristics and functions of the queen and the drones. Honeybees, though smaller than bumblebees, resemble them in their general plan of structure; that is, both kinds of insects have a head, thorax, and abdomen, all

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more or less covered with hair, and on the thorax are two pairs of membranous wings and three pairs of jointed legs. In every colony of bees there is, except at rare intervals, only one queen. The queen-bee (Fig. 24) can be readily distinguished from all the other individuals in the hive by her long, slender abdomen (Fig. 24). It is her sole busi

ness to deposit an egg in each of the various wax cells of the brood chamber. Queens have been known to lay 3000 eggs in a single day, and since a queen may live as long as five years, she may lay over 1,000,000 eggs during a lifetime. The queen is therefore the mother of all the bees in a colony.

The distinguishing characteristics of drone or male bees (Fig. 24) are their broad abdomens, the absence of a sting, and their very large, compound eyes, which nearly meet on the top of their heads. In numbers they vary at different

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times of the year, but during the summer there are usually 400 to 800 in a hive.

We learned in our study of reproduction in plants that egg-cells will not develop into seeds unless they are fertilized by sperm-cells of pollen grains. Now in a beehive, an egg will never develop into a queen-bee or a worker unless it likewise is fertilized by a sperm-cell. The drones or male bees supply these necessary sperm-cells. From the unfertilized eggs, which a queen may lay, develop only drone bees. In this respect these egg-cells of bees are strikingly different from those of plants and of most animals.

It is clear from the foregoing account that the queen and drones carry on the reproductive functions of the colony, for they are specially adapted to increase the number of bees in a hive. To the workers, on the other hand, as we shall now see, belong most of the nutritive functions of the colony.

28. Characteristics of worker bees. While the workers are smaller than either the queen or the drones, they are by far the most numerous, there being as many as 50,000 in a good colony in midsummer. In shape they resemble the queen, as one would expect, since they are undeveloped female bees. As was the case with the bumblebee, their mouth parts are very complicated, consisting of a central tongue and two other pairs of appendages, all of which form a hollow tube for sucking up the

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FIG. 26. Hind leg of bee with pollen, inner surface.

face of the tibia, forms a pollen basket similar to that of the bumblebee. In this the insect gathers a mass of pollen which may easily be seen when the workers are returning to the hive (Fig. 26).

29. Comb building.

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All the work of comb manufacture is carried on by the worker bees, and when one studies this process carefully, it is found to be one of the greatest marvels of animal activity. The cells of the comb are built out horizontally from each side of a central partition in a brood frame or of a super box. To

save the bees' time and to insure even comb, beekeepers usually insert in the frames or honey boxes thin sheets of wax "foundation" on which the bases of the cells have been impressed by machinery. Upon this the workers build the comb outward. But without this assistance from man the comb cells are usually remarkably regular

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and show the greatest economy in the use of wax. The cross section of each cell is a hexagon, and so these compartments fit together without any spaces between them as would occur if the cells were cylinders. (See Fig. 27.) This hexagonal shape also permits a single partition wall to serve for two adjacent cells, and it is evident that this shape of cell more closely fits the body of the bee than would a four-sided cell. The worker bees build two different sizes of cells in the comb. Most of the cells average about twenty-five to a square

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inch, and in these the fertilized eggs are laid, which, as we have said, develop into workers. The cells in which unfertilized eggs are deposited are somewhat larger. These form the so-called drone comb.

The wax from which the comb is produced oozes out from certain glands on the ventral surface of the abdomen of the workers. When producing the wax the bees hang motionless inside the hive for several days, each holding to the bees above. They have al

ready gorged themselves with honey, and it is estimated that from seven to fifteen pounds of honey are required to produce one pound of wax. As the little plates of wax are formed, they are seized by a bee and carried with its mandibles or under its "chin to the comb where the building is going on. Here the wax is pressed against one of the walls.

30. Honey making.

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While studying flowers we learned that they secrete a sweet liquid known as nectar. It is this that the

workers use for honey manufacture. The bee inserts into the blossom its sucking tongue and pumps up the nectar into a sac known as the honey stomach (Fig. 28). Here a kind of digestion takes place whereby the nectar is changed to honey. If the worker

bee is hungry, it opens

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-honey

stomach

true stomach

air sac

breath

a little trapdoor and allows the honey and ing pore pollen to pass into the true stomach. But since the insect usually makes more honey than it can use, when it returns to the hive it squeezes its tiny honey stomach and deposits the surplus in the cells of the comb. This honey, when first made, contains a good deal of water; it would therefore take up too much room in the comb and it would be more likely to run out from the horizontal cells. Hence, some of the workers fan with their wings and evaporate the surplus water. When the cells are completely filled, they are capped over with wax.

FIG. 28.- Internal organs of bee. (Lang.)

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