The dat DS)’ @ RY sof FON65 DS OG Base | iG 
horns, Fig. xv. a, each with a ftiff hair growing 
out of it, Near the horns appear the eyes, which 
are red, pretty large, and of a reticular net-like 
form; between the eyes, there ftretches along the 
middle of the head, a black zone or prominent 
ftreak, in which are placed three feparate and 
difting: eyes in the form of a triangle. Thefe 
are much more difcernible on the Fly’s firft ap- 
pearance in the air, than afterwards, as the ftreak 
or zone juft mentioned requires fome time to 
grow black, and has, befides, fome hairs on it, 
which do not erect themfelves, till, by drying, 
they become fufficiently firm for that purpofe. — 
The thorax is covered with ftiff hairs, of a 
brown colour, but of a polifhed and thining fur- 
face, like a looking-glafs. From its lower part 
rife fix legs: the firft or fore-pair of them, 4 4, 
are almoft black: in the fecond pair only, the 
joint near the breaft is of this colour; and the 
other two extreme joints, cc, of a dark brown. 
The third pair, dd, very nearly refemble the 
firft: but thefe colours are not exactly the fame 
in all the Flies of this fpecies. All thefe legs are 
covered with ftiff hairs, and are each of them 
armed at their extremities with two claws, by 
means of which the infect runs very nimbly 
upon glafs, by darting them into the pores of it, 
not but that it can walk very well when thofe 
fi Jd 
moift, it cannot hang itfelf to fo fmooth' a for 
face. ‘The wings are two; they are of a beau- 
tifal conftruétion, and arife from the flope of the 
breaft, ee; they are bordered with fine hairs, 
and the filaments which run through them like 
fo many little nerves, are no other than ramifi- 
cations of pulmonary tubes. The membrane 
which fills up the {paces between thefe ramifica~ 
tions, is likewife elegantly conftructed : it is co- 
vered with little prominent papille, but a draw- 
ing ten times larger than this, would hardly be 
{ufficient to do juftice to this and other wonders, 
difcoverable in the wings of flying infe@s. The 
hinder part of the thorax is, by way of orna- 
ment, furrounded with a little prominent bor- 
der; near which appear two very fimall oblong 
particles, with round heads, refembling mallets 
or hammers: itis by ftriking thefe little hammers 
againft its wings, that the Fly makes the hum- 
ming or buzzing noife that is peculiar to it *. 
The body confifts of feven rings ; it is covered 
with delicate hairs, f; and is of the fame re- 
{plendent dark brown colour with the thorax, 
The female differs from the male externally, 
in nothing but fize: but the genital parts of the 
two fexes are very different, as I thall now en- 
deavour to demonftrate, 
nails are cut off; but then, though its feet are 
Of the genital parts of the male and female Mite-Fly, and the manner of their 
coupling. 
HE Mite has a penis, two tefticles, feminal 
veflels, and proftate; and the female its 
ovary, its womb, and the parts naturally be- 
longing to it, ‘The penis of the Mite is fo art- 
fully contrived, that the feven wonders of the 
world together, cannot compare with it; nor is 
it furprifing they fhould not, they being the 
works of men, whereas this little organ is the 
conftruction of an Almighty and all-feeing Ar- 
chitect. It is partly membranaceous, and partly 
of a fubftance between bone and horn; the 
length, and inflexions of it alfo, are fo uncom- 
mon, that itis impoflible to confider it, without 
being loft in aftonifhment. 
That part of the penis, which confifts of a 
fubftance between bone and horn, is black, and 
extends only along one fide of it, Tab. XLII. 
Fig. xvil.a@; but this is enough te give the 
penis great ftrength and firmnefs, and to keep it 
always open, in readinefs to perform its duty. 
The other fide of the penis is membranaceous, 4, 
and confifts of many tranfparent rings and glo- 
bules. ‘The fore-end of the penis is alfo mem- 
branaceous and obtufe, c, though I have fome- 
times feen it pointed with fomething like an ar- 
ticulation at its extremity. It generally, how- 
ever, appears blunt and open. I cannot tell whe- 
ther or no the penis can erect itfelf through this 
opening; but I know of a certainty, that the 
vulva of the female pafies into the faid opening, fo 
* The French call thefe two parts Balanciers, Balancers; and their fyftem is, 
amends for the want of another pair of wings. 
none that have four wings. ‘Thefe fyflems are not contradi&tory, 
v 
as to form a kind of copulation, quite different 
from that of other animals, in which the penis 
is received into the female external organ of ge- 
neration, It was by meer accident that I dif- 
covered this fingularity in the copulation of the 
Mite-Flies: on examining a female, which had 
died for want of food, in the very at of copu- 
lation, I found the penis of the Mite withered 
round the vulva of the female, where it had 
been applied ; but was then fo loofely engaged, 
that I eafily feparated them. 
The penis lies on the outfide of the body, and 
is very eafily difcerned, as it extends along the 
body, with only its right fide covered by the Jaft 
ring. Itis elegantly coiled up, and refembles 
very much the penis of Drakes, which is like- 
wife folded up in the fame manner, ‘This bird, 
it feems, does not ejaculate its feed through any 
perforation within the penis, but by a furrow of 
channel on its outfide, This I have likewif 
found to be nearly the cafe in fome other ani- 
mals. 
The other parts of the male Fly fubfervient 
to generation, are likewife very well worth our 
attention, but they lie hid within the body. The 
firft that offers itfelf to our confideration, is the 
nervous root of the penis, d, which is of a very 
bright white, and reaches to the laft ring of the 
infeét’s body, where the external part of the 
penis is covered with very fine hair, ‘Fhis white 
that they affift in flying; and in fome meafure make 
There is probability in this opinion, becaufe all two winged Flies have them; and 
for they may anfwer both thefe purpofes. 
root 
