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Observ. XLIII. Of the Water-Insect_ or Gnat._
This little creature, described in the first Figure of the 27. Scheme, was a small scaled or crusted Animal, which I have often observ’d to be generated in Rain-water; I have also observ’d it both in Pond and River-water. It is suppos’d by some, to deduce its first original from the putrifaction of Rain-water, in which, if it have stood any time open to the air, you shall seldom miss, all the Summer long, of store of them frisking too and fro.
’Tis a creature, wholly differing in shape from any I ever observ’d; nor is its motion less strange: It has a very large head, in proportion to its body, all covered with a shell, like other testaceous Animals, but it differs in this, that it has, up and down several parts of it, several tufts of hairs, or brisles, plac’d in the order express’d in the Figure; It has two horns, which seem’d almost like the horns of an Oxe, inverted, and, as neer as I could guess, were hollow, with tufts of brisles, likewise at the top; these horns they could move easily this or that way, and might, perchance, be their nostrils. It has a pretty large mouth, which seem’d contriv’d much like those of Crabs and Lobsters, by which, I have often observ’d them to feed on water, or some imperceptible nutritive substance in it.
I could perceive, through the transparent shell, while the Animal surviv’d, several motions in the head, thorax, and belly, very distinctly, of differing kinds which I may, perhaps, elsewhere endeavour more accurately to examine, and to shew of how great benefit the use of a Microscope may be for the discovery of Nature’s course in the operations perform’d in Animal bodies, by which we have the opportunity of observing her through these delicate and pellucid teguments of the bodies of Insects acting according to her usual course and way, undisturbed, whereas, when we endeavour to pry into her secrets by breaking open the doors upon her, and dissecting and mangling creatures whil’st there is life yet within them, we find her indeed at work, but put into such disorder by the violence offer’d, as it may easily be imagin’d, how differing a thing we should find, if we could, as we can with a Microscope in these smaller creatures, quietly peep in at the windows, without frighting her out of her usual byas.
The form of the whole creature, as it appear’d in the Microscope, may, without troubling you with more descriptions, be plainly enough perceiv’d by the Scheme, the hinder part or belly consisting of eight several jointed parts, namely, ABCDEFGH, of the first Figure, from the midst of each of which, on either side issued out three or four small brisles or hairs, I, I, I, I, I, the tail was divided into two parts of very differing make; one of them, namely, K, having many tufts of hair or brisles, which