Micrographia - or some physiological descriptions of minute bodies made by magnifying glasses with observations and inquiries thereupon/Chapter 42
Observ. XLII. Of a blue Fly.
This kind of Fly, whereof a Microscopical Picture is delineated in the first Figure of the 26. Scheme, is a very beautifull creature, and has many things about it very notable; divers of which I have already partly describ'd, namely, the feet, wings, eyes, and head, in the preceding Observations.
And though the head before describ'd be that of a grey Drone-Fly, yet for the main it is very agreeable to this. The things wherein they differ most, will be easily enough found by the following particulars:
First, the clusters of eyes of this Fly, are very much smaller then those of the Dron-Fly, in proportion to the head.
Schem. XXVI. And next, all the eyes of each cluster seem'd much of the same bigness one with another, not differing as the other, but rang'd in the same triagonal order.
Thirdly, between these two clusters, there was a scaly prominent front B, which was arm'd and adorn'd with large tapering sharp black brisles, which growing out in rows on either side, were so bent toward each other neer the top, as to make a kind of arched arbour of Brisles, which almost cover'd the former front.
Fourthly, at the end of this Arch, about the middle of the face, on a prominent part C, grew two small oblong bodies, D D, which through a Microscope look'd not unlike the Pendants in Lillies, these seem'd to be jointed on to two small parts at C, each of which seem'd again jointed into the front.
Fifthly, out of the upper part and outsides of these horns (as I may call them, from the Figure they are of, in the 24. Scheme, where they are marked with F F) there grows a single feather, or brushy Brisle, E E, somewhat of the same kind with the tufts of a Gnat, which I have before described.
What the use of these kind of horned and tufted bodies should be, I cannot well imagine, unless they serve for smelling or hearing, though how they are adapted for either, it seems very difficult to describe: they are in almost every several kind of Flies of so various a shape; though certainly they are some very essential part of the head, and have some very notable office assign'd them by Nature, since in all Insects they are to be found in one or other form.
Sixthly, at the under part of the face F F, were several of the former sort of bended Brisles, and below all, the mouth, out of the middle of which, grew the proboscis G H I, which, by means of several joints, whereof it seem'd to consist, the Fly was able to move to and fro, and thrust it in and out as it pleas'd; the end of this hollow body (which was all over cover'd with small short hairs or brisles) was, as 'twere, bent at H, and the outer or formost side of the bended part H I, slit, as it were, into two chaps, H I, H I, all the outside of which where cover'd with hairs, and pretty large brisles; these he could, like two chaps, very readily open and shut, and when he seem'd to suck any thing from the surface of a body, he would spread abroad those chaps, and apply the hollow part of them very close to it.
From either side of the Proboscis, within the mouth, grew two other small horns, or fingers, K K, which were hairy, but small in this Figure; but of another shape, and bigger in proportion, in the 24. Scheme, where they are marked with G G, which two indeed seem'd a kind of smellers, but whether so or not, I cannot positively determine.
The Thorax or middle part of this Fly, was cas'd, both above and beneath, with a very firm crust of armour, the upper part more round, and covered over with long conical brisles, all whose ends pointed backwards; out of the hinder and under part of this grew out in a cluster six leggs, three of which are apparent in the Figure, the other three were hid by the