Another little fly belonging to this same family group—the hump-backed flies or _Pharidæ_—has it fate linked with that of bees, in whose hive it is hatched and on whose eggs and larvæ it feeds; nor does the grown bee itself, though armed with its sting, escape from the more rapacious members of the order. These are known by the name of Robber Flies, though as the robbery involves the death of the victim, and consists of the juices of its body, murder would seem to be the better word. These flies, though of somewhat slender build, which the better fits them for their swift and darting flight, are excessively strong, as might be expected from their long muscular-looking legs and rough hairy bodies. All sorts of insects are their prey, for the despatch of which they are furnished with a hard tubular beak, enclosing, as in a sheath, a lancet-like instrument, which, being protruded at will, severely lacerates the body of the captive. The beak, or sheath, is also struck some way into the wound, and being tipped with bristles, these serve as so many barbs to keep it in position, whilst the blade continues to probe and hack the victim, on whose back the fly has descended, embracing it with its powerful legs. “These flies,” says Dr. Fitch—who seems strangely unalive to the moral beauty underlying the mere mechanical expression of it—“are inhuman murderers, they are savages of the insect world, putting their captives to death with merciless cruelty. Their large eyes, divided into such a multitude of facets, probably give them the most acute and accurate vision for espying and seizing their prey; and their long, stout legs, their bearded and bristly head, their whole aspect indicates them to be of a predatory and ferocious character. Like the hawk, they swoop upon their prey, and grasping it securely between their fore feet, they violently bear it away.”[17] Bees, beetles, butterflies, moths, even grasshoppers are thus treated, and sometimes, by a beautiful retributive arrangement—enough to throw one into ecstasies—they turn cannibals, and prey upon each other. Nay, there is even more than this to arouse our admiration, for so stern and unbending is the law of eternal justice, that even the softest feelings of nature are not allowed to interfere with it, and the female, wooed by the male, is frequently compelled to eat him. Thus the noble maxim of _fiat justitia ruat cælum_, though, for a time, it may seem to be in abeyance, finds, at last, unconscious expression, if not in the breast, at least in the appetite of a cruel and murderous insect; and thus in the animal world, not less than in our human one, “the whirligig of time brings in his revenges.”