roscope_.

Intermingled likewise with these hairs, may be perceived multitudes of
little pits, or black spots, in the exended membrane, which seem to be the
root of the hairs that grow on the other side; these two bodies seem
dispers'd over the whole surface of the wing.

The hairs are best perceiv'd, by looking through it against the light, or,
by laying the wing upon a very white piece of Paper, in a convenient light,
for thereby every little hair most manifestly appears; a _Specimen_ of
which you may observe drawn in the fourth _Figure_ of the 23. _Scheme_, AB,
CD, EF whereof represent some parts of the bones or quills of the wing,
each of which you may perceive to be cover'd over with a multitude of
scales, or bristles, the former AB, is the biggest stem of all the wing,
and may be properly enough call'd the cut-air, it being that which
terminates and stiffens the formost edge of the wing; the fore-edge of this
is arm'd with a multitude of little brisles, or Tenter-hooks, in some
standing regular and in order, in others not; all the points of which are
directed from the body towards the tip of the wing, nor is this edge onely
thus fring'd, but even all the whole edge of the wing is covered with a
small fringe, consisting of short and more slender brisles.

This Subject, had I time, would afford excellent matter for the
contemplation of the nature of wings and of flying, but, because I may,
perhaps, get a more convenient time to prosecute that speculation, and
recollect several Observations that I have made of that particular. I shall
at present proceed to

* * * * *

Observ. XXXIX. _Of the Eyes and Head of a _Grey drone-Fly_,
and of several other creatures._

I took a large grey _Drone-Fly_, that had a large head, but a small and
slender body in proportion to it, and cutting off its head, I fix'd it with
the forepart or face upwards upon my Object Plate (this I made choice of
rather then the head of a great blue Fly, because my enquiry being now
about the eyes, I found this Fly to have, first the biggest clusters of
eyes in proportion to his head, of any small kind of Fly that I have yet
seen, it being somewhat inclining towards the make of the large
_Dragon-Flies_. Next, because there is a greater variety in the knobs or
balls of each cluster, then is of any small Fly.) Then examining it
according to my usual manner, by varying the degrees of light, and altering
its position t