Page:Encyclopædia Britannica, Ninth Edition, v. 3.djvu/502

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486
BEE

knead it together into a ball, and place it in the space situated at the middle joint or tibia of the hinder leg, which has been termed the basket. This portion of the leg is smooth and concave, somewhat like the bowl of a spoon, with stout hairs of moderate length rising from its left edge and nearly straight, Other hairs on the right side are much longer and are curved, rising up with a high arch and crossing more than half the width of the hollow, making a large basket-like enclosure for a load of pollen. In order to gather large quantities at once, the bees are sometimes observed to roll their bodies on the flower, and then brushing off the pollen which adheres to them with the feet, form it into two masses, which they dispose of as before mentioned ; and it is said that in moist weather, when the particles of pollen cannot be readily made to adhere, they return to their hive dusted all over with pollen, which they then brush off with their feet. The part in Nature s economy thus unconsciously performed by the bee in common with other insects is most important. By this means the pollen is carried from flower to flower, or from the stamens to the pistils, and plants are made fertile which

without such aid would often remain barren.

It was long the received opinion that wax was but a modification of pollen, which required for this conversion only a slight pressure and a kind of kneading by the feet of the bees. But it has been completely proved, by the researches of Duchet, Hunter, and Huber, that wax is a secretion from the abdomen of the bee, and that it depends not at all on the pollen which the insect may con sume (indeed, it is doubtful if it consumes any), but on the quantity of honey or other saccharine substance which it receives into its stomach. The first light thrown on this subject was in a letter of Wilhelmi to Bonnet in 1768, in which he says that wax, instead of being ejected by the mouth, exudes from the rings which enclose the posterior part of the body. Of this we may satisfy ourselves by drawing out the bee from the cell in which it is working with wax, by means of the point of a fine needle ; and we may perceive, in proportion as the body is elongated, that the wax will make its appearance under the rings in the form of small scales. Duchet, in his Culture des Abeilles, gives a full statement of the principal circumstances attend ing the production of wax, which he very justly ascribes to the conversion of honey into this substance in the body of the bee. These facts appear to have been entirely over looked till the subject was again brought forward by Hunter, in his paper in the Philosophical Transactions for 1792. Huber was engaged in prosecuting his inquiries on this subject at the same period with Hunter, and discovered, in 1793, the existence of regular receptacles or pouches, from the coats of which the wax is secreted, and within which it accumulates till its edges raise the scales, and become apparent externally. These plates of wax are withdrawn by the bee itself, or some of its fellow-labourers, and are applied in a manner hereafter to be described.

Huber has shown, by a series of well-conducted experi ments, that, in a natural state, the quantity of wax secreted is in proportion to the consumption of honey, but that an equal or even greater quantity will be formed if the bee be fed on a solution of sugar in water. Warmth and rest promote this process of secretion ; for the bees, after feeding plentifully on saccharine food, hang together in a cluster without moving, for several hours, at the end of which time large plates of wax are found under the abdominal rings. This happened when bees were confined and restricted from any other sort of nourishment, whilst those that were fed on pollen and fruits alone did not produce any wax. In the second volume of Huber s Nouvelles Observations sur les Abeilles, he describes minutely the anatomy of the pouches or receptacles for the wax, which are parts peculiar to the working bees, being totally absent in the males and queens, The cavities are lined with a membrane, which presents a number of folds, forming an hexagonal net-work, not unlike the appearance in the second stomach of ruminant quadrupeds, and evidently destined to perform the office of secretion.

Among the secretions peculiar to the bee, the poison which is poured into the wounds made by the sting deserves to be noticed. It is said to owe its mischievous efficacy to certain pungent salts. If a bee is provoked to strike its sting against a plate of glass, a drop of poison will be discharged ; and if this is placed under a microscope, the salts may be seen to concrete, as the liquor dries, into clear, oblong, pointed crystals. The sting consists of a finely-pointed tubular instrument, open along the whole length of its upper surface, this opening being closed by two slender horny barbs each having about ten serrations on its outer edge. These barbs are not projected in advance of the sting as usually described, neither are they within the sting, but complete its outer tubular surface, down the centre of which the poison is injected from a little bag at the root of the sting. The serrations prevent the worker bee from withdrawing its sting from an enemy ; and, con sequently, it is torn from the body, with a portion of the intestines, causing the death of the bee.

Respiration is effected by means totally different from Fmi those which are usual in the higher classes of the Animal f r Kingdom. As the blood, or fluid corresponding to the tin " blood, cannot be presented to the air in any separate organ, the air must be conducted to the blood wherever such a fluid is met with. For this purpose tracheae, or air-tubes, having several external openings or spiracles, are made to ramify like arteries, and are distributed in an infinite number of branches to every part of the body. The con dition of a hive of bees in which many thousand individuals, full of animation and activity, are crowded together in a confined space, having no communication with the external air but by means of a very small aperture in the lowest part, which aperture is frequently obstructed by a throng of bees passing in and out during sultry weather, would without some precautions be of all possible conditions the one least favourable to life. Bees cannot exist in an impure atmosphere any more than creatures of a larger growth. And on examining the air of a populous hive it is found Ven scarcely to differ in purity from the surrounding atmosphere. of t: The means by which this is effected observation has shown is by the rapid vibration of the bees wings, a certain number being told off to imitate the action of flying, for which purpose they fasten themselves with their feet to the floor of the hive, so that the whole effect of that impulse which, were they at liberty, would carry them forwards with considerable velocity is exerted on the air, wnich is therefore driven backwards in a powerful current. Some bees occasionally perform these ventilating motions on the outside of the hive, near the entrance, but a still greater number are employed in this office within doors. Sometimes twenty are thus occupied at once, and each bee continues its motions for a certain time, occasionally for nearly half an hour, and is then relieved by another, which takes its place. So rapid a motion of the wings is thus produced that they cannot be seen except at the two extremities of the arc of vibration, which is at least one of 90. This is the occasion of that humming sound which is constantly heard from the interior of the hive when the bees are in a r l ate of activity. The immediate cause of these actions is probably some impression made on their rgans by the presence of vitiated air, for a bee may bo made to ventilate itself by placing near it substances which liave to it an unpleasant odour.

The connection between an active respiration and a high