The Eers T O'R Yo a ViINISCERC ® 6. 
or bony matter, and was moderately ftrong 
and yet flexible. But upon examining this lit- 
tle part afterwards with a larger magnifying 
glafs, I obferved that there was a confiderable 
aperture juft below its fharp point; and I alfo 
obferved two little drops of a real liquor, at 
fome diftance from each other, lying in the 
middle of this little part, as in a little hollow 
tube. As I was attempting to exprefs or get 
out this liquid under the microfcope, it hap- 
pened, contrary to my expectations, that I broke 
that little part. This accident had great ad- 
vantage, for on the infide of this little part I 
then difcovered five diftiné aculei or ftings, and 
confequently thus found the whole conftruction 
of the aculeus. 
I obferved that two of thefe aculei which 
were hidden within the tubulated little canal 
of the general thing were, much more flender, 
Tab. XXXII. fig. 111. ¢ c, than the three others, 
which appeared thicker and ftronger, ddd. 
I likewife obferved that they were fomewhat 
broader where they were articulated with the 
head, but that they afterwards became {mall, 
and that they were finally confiderably extend- 
ed, before they terminate in their delicate and 
fine points. All thefe aculei were of a delicate 
fmooth furface, but in the middle they were 
fomewhat thicker and more diftended, fo that 
in that part they appeared of a browner colour, 
exhibiting to the eye within a pellucid bright 
rednefs: but they confifted of a flexible 
horny or bony matter like that of the little 
canal which contained them. I could not dif 
cover any cavity inthem, though there feemed. 
to be fomething of this kind in the larger ; for 
when thefe were examined with a very acute 
glafs, they curled and continually moved about: 
this, I thought, muft be attributed to the eva- 
poration of the humour inclofed or contained 
within their fubftance. I could by no means, 
however, obferve any other mark of their being 
hollow on the infide. 
As to the ufe of thefe five aculei, they feem 
only to ferve as fo many very fharp lances to 
enter the pores of the skin, and afterwards to 
retract or draw themfelves back into the inward 
cafe wherein they are kept: but then I fhould 
think that the acute and hollow extremity of 
this cafe is certainly introduced into the wound, 
and by means. thereof the Gnat afterwards 
fucks the blood, which, running or afcending 
by fuction between thefe fharp parts, is at 
length conveyed into the body of the infec. 
Hence there appears almoft the fame ute of this 
fheath as there is of the filver pipes ufed by 
our furgeons, through which they pafs their 
_ lancets when they are about to open ulcers that 
lie deep between the jaws, and are careful to 
wound no other parts but thofe they are to cut. 
The reafon why nature hath made five aculei 
for this purpofe, is, I confefs, beyond my com- 
prehenfion, unlefs one fhould incline to think 
that by the repeated agitation of fo many things 
in the womb, the blood is better prepared to 
ig7 
afcend through this long and moft flender tube 
wherein thofe ftings are hidden: 
I am firmly perfuaded that when the Gnat 
has no opportunity of drawing blood out of 
animals; it fucks, with the help of its cafe, the 
juices of flowers, plants or fruits, being con- 
tent with feeding on the latter when it wants 
the former : indeed, by what other means could 
it fupport itfelf; when it lives in the fields and 
woods? I would not now prefume to affirm 
for certain, whether, when. I firft communi- 
cated to the public the figure of the Gnat’s 
trunk, not knowing then that it had five ftings, 
I faw one or more ftings projecting or hanging 
out of its cafe; but Iam not certain now that 
thefe five ftings, viewed fideways, do not ap= 
pear broader in the fore part next under their 
points than elfewhere. 
After I had made the obfervations already 
mentioned on the fting of the Gnat, I often 
afterwards obferved in the dead Gnats, that all 
their ftings were broken off from their cafe; 
and appeared without the little tube, without 
my aid. And hence I began to confider, whe- 
ther thefe integuments of the five {tings refem- 
ble or not the fheath or cafe of a Bee’s {ting, 
and only or loofely contain the real fting, as a 
{cabbard open on one fide might hold a fword. 
But, notwithftanding the repeated pains I have 
hitherto taken to difeover the truth in this 
matter, yet I could never find out any mark 
of fuch a ftructure. I therefore think I may 
fafely maintain that both the cafe of the fting 
and its inward pipe are two diftinét and entire 
integuments, the exterior of which contains the 
little tube, and the interior, which is the little 
tube itfelf, contains the five ftings. 
It has fometimes happened, that upon ex- 
amining thefe things in other {pecies of Gnats, 
I have obferved that, like the ftings of Bees, 
they were provided with a kind of crooked 
claws, or were at leaft ferrated on their fur- 
face. But this I had not the good fortune to 
fee when I was engaged in drawing and finifh- 
ing the figures of thefe parts from the prefent 
{pecies ; only I thought I once faw fomething 
like it through the commion microfcopes, and 
therefore thofe who are fond of microfcopes, 
muft take care not to confide in one lens or 
glafs only, and. muft not always view the ob- 
ject in the fare manner and fituation, for by 
this means many errors arife. In the third 
figure above mentioned is likewife feen the 
neck, Tab. XXXII. fig. 111. ¢, of the Gnat, 
and the head / placed thereon, in which the eyes 
£& & appear, as alfo the antenne cut off b 4, and 
the articulated fetae for briftly hairs77, which 
are cut off above the ftings. f 
As to the thorax of the Gnat, it carries the 
legs and wings, and alfo two little parts like 
hammers, and of an oval figure. The legs are 
of a brownith colour, and confift of {even 
joints, fig. 1. ff ff, which are larger in the 
hinder that in the fore legs: but befides thefe, 
the extremity of each leg is likewife armed 
Sf with 
