[r] By Reason it would be endless to specify the various Generation of Insects in the Water, I shall therefore (because it is little observed) raise Pliny’s Instance of the Gnat, a mean and contemned Animal, but a notable Instance of Nature’s Work, as he saith.
The first Thing considerable in the Generation of this Insect is (for the Size of the Animal) its vast Spawn, being some of them above an Inch long, and half a quarter Diameter; made to float in the Waters, and tied to some Stick, Stone, or other fix’d Thing in the Waters, by a small Stem, or Stalk. In this gelatine, transparent Spawn, the Eggs are neatly laid; in some Spawns in a single, in some in a double spiral Line, running round from end to end, as in [Fig. 9, and 10]; and in some transversly, as [Fig. 8.]
When the Eggs are by the Heat of the Sun, and Warmth of the Season hatched into small Maggots, these Maggots descend to the bottom, and by means of some of the gelatine Matter of the Spawn (which they take along with them) they stick to Stones, and other Bodies at the bottom, and there make themselves little Cases or Cells, which they creep into, and out of at Pleasure, until they are arrived to a more mature Nympha-State, and can swim about here and there, to seek for what Food they have occasion; at which Time, they are a kind of Red-worms, above half an Inch long, as in [Fig. 11.]
Thus far this mean Insect is a good Instance of the divine Providence towards it. But if we farther consider, and compare the three States it undergoes after it is hatched, we shall find yet greater Signals of the Creator’s Management, even in these meanest of Creatures. The three States I mean, are its Nympha-Vermicular State, its Aurelia, and Mature-State, all as different as to Shape and Accoutrements, as if the Insect was three different Animals. In its Vermicular-State, it is a Red-Maggot, as I said, and hath a Mouth and other Parts accommodated to Food: In its Aurelia-State it hath no such Parts, because it then subsists without Food; but in its Mature, Gnat-State, it hath a curious well-made Spear, to wound and suck the Blood of other Animals. In its Vermicular-State, it hath a long Worm-like Body, and something analogous to Fins or Feathers, standing erect near its Tail, and running parallel with the Body, by means of which resisting the Waters, it is enabled to swim about by Curvations, or flapping its Body, side-ways, this way and that, as in [Fig. 12.]
But in its Aurelia-State, it hath a quite different Body, with a Club-Head (in which the Head, Thorax, and Wings of the Gnat are inclosed) a slender Alvus, and a neat finny Tail, standing at right Angles with the Body, quite contrary to what it was before; by which means, instead of easy flapping side-ways, it swims by rapid, brisk Jirks, the quite contrary way; as is in some measure represented in [Fig. 13.] But when it becomes a Gnat, no finny Tail, no Club-Head, but all is made in the most accurate manner for Flight and Motion in the Air, as before it was for the Waters.
[] See [Book IV. Chap. 13. Notes (n), (o).]
[t] Thus the Mouths and other Parts of the Ichneumon-Wasps in [Book IV. Chap. 13. Note (t).] So the Feet of the Gryllotalpa, ibid. [Note (s).]
[] See the last cited Places, [Note (o).]
[w] Of the textrine Art of the Spider, and its Parts serving to that Purpose, see the last cited Place, [Note (x).]
Besides these, Caterpillars, and divers other Insects, can emit Threads, or Webs for their Use. In this their Nympha-State, they secure themselves from falling, and let themselves down from the Boughs of Trees, and other high Places, with one of these Threads. And in the Cases they weave, they secure themselves in their Aurelia-State.