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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 troublin