Barred with ash-grey velvet on a black ground, the Big-jawed Staphylinus reaches me only in small numbers, always one by one. She flies up hastily, perhaps from the stables hard by. She alights, coils her belly, opens her pincers and dives impetuously into the Mole’s fur. Then, with her powerful nippers, she punctures the skin, now blue and distended by gases. The sanies oozes out. The glutton greedily eats her fill; and that is all. Soon she departs, as suddenly as she came.
I have not had the good fortune to see anything further. The big Staphylinus hastens to my pans only to feast upon a highly seasoned dish. Her family dwelling must be in the dung-hills about the stables of the neighbourhood. I should have much liked to see her make her home in my charnel-pits.
The Staphylinus is a curious creature indeed. Her short wing-cases, covering just the top of her shoulders, her fierce mandibles, [[50]]overlapping like a meat-hook, and her long, naked abdomen, which she lifts and brandishes in the air, make her a being apart, of alarming aspect. I should like to learn something of her larva. As I cannot do this with the Beetle that visits my Moles, I apply myself to a kindred species, as nearly as possible her equivalent in respect of size.
In winter, when I raise the stones beside the foot-paths, I often come across the larva of the Stinking Staphylinus (S. olens, Müll.), or Devil’s Coach-horse. The ugly animal, which is not very different in shape from the adult, measures about an inch in length. The head and thorax are a fine, glossy black; the abdomen is brown and bristles with sparse hairs. The cranium is flat; the mandibles are black and very sharp, opening in a ferocious crescent whose width is more than twice the diameter of the head. The mere sight of these curved daggers enables us to guess the highwayman’s habits.
The creature’s most singular implement is the end of the intestine, which is covered with a horny substance prolonged into a stiff tube standing at right angles to the axis of the body. This member is an instrument of locomotion, an anal crutch. In walking, [[51]]the animal presses the tip of this crutch to the ground and thrusts backwards as with a lever, while the legs struggle forward. Doré,[13] the famous illustrator of extravagant notions, conceived a similar system. He shows us somewhere a legless cripple seated in a bowl supported by a pivot and working himself along on his hands. The artist’s grotesque imagination might well have been inspired by the grotesque appearance of the insect.
Even among its own kind, the crutched insect is a bad neighbour. Very rarely do I find two larvæ under the same stone; and, when this happens, one of the two is always in a pitiful state: the other is devouring it as if it were its ordinary game. Let us watch this conflict of two cannibals, each thirsting for the other’s blood.
In the arena furnished by a tumbler containing some moist sand, I place two larvæ of equal strength. The moment they face each other, they suddenly rear up, bending their bodies backwards, with the six legs in the air, hooks of the mandibles wide open and the anal crutch firmly fixed. They look [[52]]magnificently audacious in this posture of attack and defence. This above all is the best moment for recognizing the great advantage of the pivot at the tail. Though in danger of being disembowelled by its adversary, the larva has no other support than the tip of the abdomen and the terminal tube. The six legs play no part in sustaining it; they wave in the air, all six free and ready to clasp the enemy.
The two adversaries are standing face to face. Which of the two will eat the other? Chance decides. Mutual threats are followed by a hand-to-hand struggle. The fight does not last long. Favoured by the hazards of the fray, or perhaps timing its blows more accurately, one seizes the other by the scruff of the neck. It is done: any resistance on the part of the vanquished is impossible; blood flows and murder has been committed. When all movement has ceased, the victor devours the slain, leaving only the unpleasantly hard skin.
Is this frenzy for killing among creatures of the same species due to cannibalism enforced by starvation? I really do not think so. When well-fed to begin with, rich, moreover, in the victuals which I lavish upon [[53]]them, these miscreants are as prone as ever to butcher their kith and kin. In vain I overwhelm them with choice morsels: succulent sausages in the shape of young Anoxia-larvæ;[14] Vitrinæ,[15] tiny molluscs which I give them half-crushed, to spare the banqueters the trouble of extracting them from the shell. As soon as they are confronted, the two bandits, which have just been feasting on a prey as bulky as themselves, stand up, challenging each other and snapping at each other until one of the two is dead. Then follows the odious meal. To eat the murdered kinsman is, it seems, the usual thing.
The Mantis[16] who, in captivity, preys upon her mates has the madness of the rutting beast as her excuse. The fierce, jealous creature can find no better way of getting rid of her rivals than to eat them, provided she be the stronger. This procreative depravity is found much higher in the scale. The Cat and the Rabbit notably are prone to devour the young family which might stand in the way of their unslaked passions. [[54]]