PULEX-Eaters, a name given by naturalists to a sort of worms frequently found on the leaves of trees, where they devour the animals called pulices arborei.
Of these there are several species, which owe their origin to the eggs of different creatures; for there are none of them in their ultimate state in this their time of feeding. According to the different animals whose eggs they are hatched from, these are of different form and structure. Some are hexapodes, or ended with six feet; these belong to the beetle-tribe, and finally change into beetles like the parent animal from whose eggs they sprung. Others have no legs, and are produced from the eggs of flies of various kinds. And, finally, others are genuine caterpillars, though small; but these are the most rare of all.
The two general kinds are the hexapodes, or beetle-worms; and the apodes, or fly-worms. The fly which gives origin to the last of these is a four-winged one; and takes care always to deposit her eggs in a place where there are plenty of the pulices, usually on the stalk or young branches of a tree in the midst of large families of them. The worm, as soon as hatched, finds itself in the midst of abundance of food, preying at pleasure on these animals, which are wholly defenceless. The stalks of the elder and woodbine are frequently found covered over with these pulices; and among them there may usually be found one or more of these destroyers feeding at will, sucking in the juices from their bodies, and then throwing away the dry skins. Besides the worms of this four-winged fly, there is one of a two-winged wasp-fly, very destructive of these animals.