§. V. POLLEN, OR BEE-BREAD.
Bees, when fully grown, feed almost wholly on honey; but the larvæ require for their development a more substantial kind of nourishment. Such solid fare is found by the bees in the pollen of flowers, a farina which contains the nitrogenous element of which honey is nearly destitute. The body of a worker bee is covered with hairs, to which the pollen adheres when, by contact with the bee, it is rubbed from the anthers of flowers (see [page 88]). Dewy mornings or humid bowers suit the bees for the gathering of the pollen. If the atmosphere be too dry for kneading it into pellets, they roll themselves in the blossoms, and on their return, with assistance from others, brush off the farina into the cells intended for it. A portion of this "bee-bread" is taken at once by the "nursing bees," who are supposed to subject it to some change before offering it to the larvæ; but the greater part of the pollen is stored away and reversed in the cells for future use. In April and May the bees are frequently busy "all the day" in gathering pollen, and often one community of bees will collect about twenty pounds weight of "bee-bread" in one season.
One of the objects of the apiarian is to assist the bees in providing for the nurslings of the hive. Dr. Dzierzon first suggested the plan of providing the bees with "unbolted rye meal" as a substitute for the farina of flowers. He had observed that, in early spring, before the flowers were open, his bees had entered a neighbouring cornmill, from whence they returned laden with rye flour. Since his discovery, some keepers, in early spring, have placed rye or wheat meal near the apiaries; to this artificial store the bees repair by thousands, and seek to rollick in the enjoyment of such plenty, many of them returning to the hive as dusty as millers. The object in thus supplying them is that the brood may be rapidly brought forward, and early swarming induced. In this way a few pounds of rye meal, at one penny per pound, may tend to the production of very many pounds of honey of twelve times the price.
In the British Bee Journal there is a recommendation to sprinkle pea flour amongst deal shavings in any open vessel, and place this near the hives so that bees have access to it. We can endorse this recommendation, for we know that it is freely taken by the bees.
If the bee-keeper ascertains that for some interval no pollen has been conveyed into any particular hive he may regard it as a sure sign that no young bees are there hatching, and consequently that the hive is without a queen. Mr. Mahan, of Philadelphia, once met with a hive which no pollen had been seen to enter for twenty-eight days; he put a queen into it, took out his watch, and observed in three and a half minutes a bee come in with pollen on its legs—many more speedily following!
Some remarks on the services which bees render to flowers will be found in the section upon "Faculties and Functions" ([page 55]).
§. VI. PROPOLIS, OR BEES' CEMENT.
"Propolis" is a Greek word which originally signified "the outskirts of a city," but was adopted by Latin writers on bees to denote the sticky substance with which these city-rearing insects protect their outskirts. It is "a resinous substance, very tenacious and semi-transparent," which is indispensable for the bees as a cement wherewith to fix their combs and fortify their hives against intruders.[33] The bees, in working the propolis, often soften it by blending it with a portion of wax; but they have to extract it in its natural state directly from the bark and buds of certain trees. The bark of the willow, the leaf-buds of the poplar and alder, and the unopened blossoms of the hollyhock are very usual sources of propolis. In the case of a new swarm, as bees must have this glue before they can begin to build their combs, they will resort to most unlikely places to obtain it. Sometimes they will enter a paint-shop and attack the varnish, and it is said they have been seen to obtain propolis from the pitch and rigging of a ship. These circumstances afford intelligible hints to the apiarian, who, if his bees have not easy access to firs, poplars, or willows, will provide some glutinous or resinous matter which may serve for a substitute. The extraction of propolis costs the bees very considerable labour, which they should be relieved of as much as possible in order to facilitate their great work of honey-gathering. Bees choose the warmer part of the day during which to gather propolis, as then it does not so rapidly stiffen. Frequently when they arrive at the hive it has become so hard that the other bees are scarcely able to gnaw it from their thighs.
[33] Egyptian bees, however, substitute wax, as stated on [page 50].
With propolis bees fasten down their hives, stop up crevices, to exclude moths and ants, and sometimes use it to narrow their doorways against the invasion of wasps. Extraordinary anecdotes are told of the prompt and ingenious use they make of this substance. Réaumur relates that, a snail having been observed by the bees on the window of the hive, they proceeded to glue the shell to the glass, and there sealed down the intruder in hopeless durance. In another case, that of a slug, the bees, having slain it with their stings, were quite unable to remove it from the hive. With wonderful foresight they then proceeded to secure their community from the noxious effects likely to arise from the decay of the carcase; and this they did by completely enveloping it with a coating of impervious varnish. Huish relates a similar occurrence in the case of a mouse caught in a hive by bees. Propolis yields benzoic acid, and contains some aromatic properties.