  Bees and Spiders, Earwigs, Beetles and Snails, Dragon-flies, Grasshoppers, and Butterflies are familiar enough to us all; yet how many realise how 'fearfully and wonderfully' they are made? What a marvellously complex weapon is the 'sting' of the bee! What a wonderful 'rasp' the snail possesses! How many can tell how an insect smells, and where its organs of taste and hearing lie? Since these are questions which young people often ask again and again, some of them will be answered in the course of these articles. To explain such matters clearly is a very difficult task, but with the aid of drawings, specially made for this purpose, the main facts at least should be easy to grasp. Most of us agree to treat the bee respectfully, having a wholesome dread of the vengeance he is likely to inflict on those who offend him. But how does a bee sting? and what is the sting like? To take the last question first. The sting of the bee is really an extremely cunningly devised weapon, so complex that only the bare outlines of its structure can possibly be described clearly. If you turn to the illustration of the bee-sting, you will notice, in the right-hand figure, at the upper end, three pointed projections or 'processes' marked. The two outer ones (s s) we may neglect, for they are only protecting sheaths; that in the middle (i s) is the sting proper. This consists of two parts, (1) a strong gouge-like portion, and (2) a pair of darts of marvellous delicacy. These darts we cannot see in position because they lie on the other side of the gouge-like piece. But to the left you will notice a This poison is made in what is called the poison gland, the long, slender, coiled tube (p g) in the picture. As the poison is made, it is stored in the big bag (marked p) at the back of the sting, and when this is working, the poison is forced down between the gouge and the darts, to find its way out at the barbs into the flesh. But this sting is not only used for the purpose of giving pain. The bee long ago discovered the fact that food, if it is to be preserved for any length of time, requires to be specially dealt with. Accordingly the honey which is destined to be kept is preserved from fermentation by the addition of a drop of formic acid deposited by the sting. Only the workers and the queen-bees of a hive have stings: the males are stingless. In stinging it often happens that the barbed darts are thrust so far into the wound that they cannot be withdrawn. As a result, the whole apparatus is left behind, and the bee pays the penalty with its life. But whilst some insects, such as the bees, inject poison by means of a 'sting,' others effect the same end by peculiar modifications of the mouth-parts. The gnat is a case in point: the water-bug, common in our ponds and ditches, is another. Strangely enough, the mechanism adopted is precisely similar in character, though the parts of which this mechanism is made up are of a totally different kind. Here, the mouth-parts are specially modified, so as to form a supporting and piercing weapon, like the 'gouge-like' piercing weapon of the bee, with delicate pointed and barbed weapons corresponding to the barbs of the bee's sting. This piercing organ may be used for sapping the tissue of plants, or, as in the case of gnats and fleas, they may be employed for the purpose of absorbing the blood of animals. In the latter case, after the surface of the skin is pierced, a poison is forced down into the wound, for the purpose, it is thought, of making the blood more fluid. But this poison is of a highly irritant nature, and leaves a very painful feeling, accompanied by more or less inflammation of the parts attacked. The water-boatman, which almost every one must have seen swimming back-downwards in ponds, can inflict a very painful wound in this manner. The illustration shows the 'lancet' of nepa, the water-bug. The piercing organ just described is the spear-shaped piece bounded on either side by two long filaments. W. P. Pycraft, F.Z.S., A.L.S. |
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