But it is not so much his odd shape as a most extraordinary property he possesses, which is singularly unique in the animal kingdom, that makes him an object of interest and curiosity. Deep down in his most marvellous body a fluid, highly volatile in its nature, is elaborated, which the little creature can retain or expel at his pleasure. It is only, however, when alarmed that he utilizes this fluid in small quantities in defense, but its effect is wonderful, for in coming into contact with the atmosphere it immediately volatilizes and explodes, looking very much like a discharge of powder from a miniature artillery. In consequence of this phenomenon the insect which produces it is popularly called the Bombardier Beetle.
BRACHINUS PURSUED BY AN ENEMY.
His Curious and Unique Method of Defence.
So small a coleopter, being scarcely one-fourth of an inch in length, and so comparatively weak, is likely to be attacked by the larger Geodephaga, or Earth Devourers, and especially by the Carabi, which inhabit similar retreats. But for this curious defence the smaller insect could have but the barest chance of living in the struggle for existence. Often have I seen a Carabus in hot pursuit of Brachinus. The chase is always an interesting one, and never fails, however frequently it has been observed, of attracting attention and exciting admiration. But the wide-awake, ever watchful Brachinus never loses his head for a second when thus pursued, but like the clever artilleryman that he is, awaits the opportune moment, and then pours a heavy discharge of his fulminating fluid into the very face of the enemy. Baffled, alarmed, Carabus desists from the attack, and backs slowly away from the tiny blue smoke, while Brachinus, in the confusion that ensues, escapes to some place of security for rest and protection.
Most skilfully has the artist delineated the [scene]. Carabus serratus, the pursuing beetle, is chasing the Bombardier, and has nearly effected his capture, when, all of a sudden, a discharge of artillery has stopped the pursuit, under cover of which the Bombardier will make off. Meanwhile the Carabus, exchanging his rapid advance for a retreat quite as rapid, throws back his antennæ, a sign of his defeat, and skulks away to recover his wonted self-possession.
The volatile fluid, which produces such curious effects, is secreted in a small sac just within the end of the abdomen. Not only is it capable of repelling the larger beetles by its explosion and cloud of blue vapor, but it is also powerful enough to discolor the human skin, as many who have captured Bombardier Beetles by the hand know only too well. Should the fluid get within the eyelids, the pain and irritation produced are very distressing. Some years ago the writer, while searching for carabi underneath stones and in creviced rocks, met for the first time with Brachinus, but was ignorant as a child of his obnoxious property. Placing a little fellow upon his hand for close examination, he soon experienced a burning and painful sensation of the ball of the eye, but did not for a long while attribute the cause to a discharge from the Beetle. Repeated investigations at very short ranges by means of a microscope were attended with similar results, till eventually an inflammation of the visual organs set in, accompanied by a blurring of the sight, which debarred him from reading and study for nearly a fortnight. One learns wisdom by experience, and the wisdom thus acquired serves for a lifetime.
Even Brachinus has learned by experience, doubtless, to be economical in the use of his resources. The whole of the contents of his tiny magazine are not ejected at one discharge, but there is sufficient to produce a series of explosions, each explosion being perceptibly fainter than its predecessor. By pressing the abdomen of the dead Beetle between finger and thumb these explosions may even be produced. In hot countries, where exceedingly large species abound, the explosions are said to be very loud, and accompanied with quite a cloud of blue vapor.
BRIGHT AND SHINING ONES.
Probably more than ninety thousand different species of beetles exist in the world, first and foremost among them standing the Cicindelidæ, or Tiger Beetles. From their high position in the coleopterous world they may well demand our attention, but they have other claims upon our consideration. They are beautiful, courageous little creatures, and accomplish a vast amount of good to man. The name Cicindela, by which they are known to scientific people, tells us that they are the “bright and shining ones;” while the cognomen of Tiger Beetle reveals to all English-speaking nations the story of the incessant warfare which they wage upon their fellows.
The Cicindelæ love the merry sunshine. On any bright summer day they may be found running and flying about sunny banks, or revelling in sandy places where the day-god smilingly rejoices. They mostly avoid vegetation, as it checks their easy rapid movements, although some kinds affect grassy spots among the trees. They are the most predaceous of the coleoptera, and behave like the tigers among mammals, the hawks among birds, the crocodiles among reptiles and the sharks among fishes. In the tropics some few genera seek their food on the leaves of trees, but in temperate and sub-tropical regions, where the species are more abundant, they are terrestrial in habits.