62 
it ereSts and ftretches itfelf. Its forepart is divided 
into three horny or bony points, Tab. XLVII. Fig. 
vit. @, variegated with a palifh yellow colour, 
fomewhat approaching to red: the middle one: 
of thefe is properly the penis, which can erect it- 
felf internally, and puth through the horny little 
bone, wherewith its hinder parts are invefted. 
It is connected as by two joints, £4, with black 
horny little bones, twifted into ferpentine wind- 
ings, which I here reprefent, joined to the hin- 
der part of its horny fheath.. Moreover, this 
can bend itfelf in fome degree about the middle, c; 
its cafe, or fheath, being there a little more mem- 
brancus: hence the penis feems to exhibit a 
joint in that part. The laft or extreme ring of 
the belly, wherewith the penis is articulated, is 
likewife adorned with two margins or verges, 
which are fmall, horny, or bony, black, and 
confiderably ftrong, dd; and in the fore- 
part, are, as it were, jointed with the horny 
little bones, which are bent in a ferpentine man- 
ner ce. | have here delineated that ring open: for 
all thefe horny little bones are clofely joined to- 
gether, and cover, as it were, the penis. 
The foft and nervous part of the penis, 
twifted in a ferpentine f manner, runs inwardly 
into the cavity of the abdomen, and is there at 
length dilated into a confiderable knot, g; into 
which the tefticles, 4b, and feminal veficles, zz, 
difcharge their {perm through four orifices, and 
thus convey itto the penis. ‘Thetefticles, when 
diffected, thew themfelves to be compofed of 
very numerous, fmall, very fhort and tender & & 
tubes, with their ends clofed; all which threw 
their {perm into the vas diferens, /, by which it 
is conveyed on further. ‘The feminal veficles 
are not fo confiderable; ,but they deferve notice, 
on account of fome bendings and curlings, mm; 
they terminate in delated extremities. ‘Their 
{perm, as well as that of the tefticles, is white ; 
though the tefticles are not fo white as the femi- 
nal veficles. 
The fpinal marrow is here difpofed in the 
fame manner as it is in the Nymph. 
I find the fame parts in the female as in the 
male; only that an ovary is found in that fex, 
inftead of the male genital organs. ‘This ovary 
is divided into two parts, Tab. XLII. Fig. virz. 
aa, and being 4 faftened to the laft rings of the 
abdomen, it opens there by a large orifice, and 
difcharges its eggs; thefe the Fly always drops 
into the water: this is likewife the practice of 
the Perlaor Dragon-fly. Thefe hinder rings of 
the body, are here and there very beautifully va- 
riegated with black, horny, or bony {pots of dif- 
ferent figures, ccc, and are likewife beautifully 
adorned all round with hairs d. 
The eggs in the ovary feem to be exactly fphe- 
tical, and to exhibit each an opening in the 
middle of it, eee: but this is only a falfe appear- 
ance, produced from their too obfcure colour. 
In reality thefe eggs, are oblong ; andthey become 
the longer and more acute, f, as alfo larger and 
more confpicuous, the longer time has paffed 
fince the Fly’s change; fo that they infenfibly 
b) 
The <B-O-O KF of N AU DUR E3Hor, 
fill the body more and more. But if thefe eggs 
be laid betore a microfcope, that maginifies in a 
great degree; then their real figure is difcovered, 
together with the pulmonary tubes, g, which 
connect them every where, and which furniih- 
ing many fhoots, 4, diffufe 72 themfelves through 
the whole ovary in feveral beautiful branches, 
No veins or arteries are feen here ; becaufe thefe 
little creatures have white blood, as alfo on ac- 
count of their great fmallnefs. 
In the young Fly thefe eggs are very tender, 
and of a beautiful colour; which becomes the 
{tronger or fuller, in proportion to its age. In 
one ovary of this kind, I have diftinétly counted 
about four hundred and forty eggs: hence it is 
evident, what a great number of Worms one 
Fly may produce. 
I have placed water, fweetened with fugar, be- 
fore {ome of thefe Worms ; but they did not touch 
it, and died the fourth day. Others lived much 
longer, and the more fo, the more they were 
expofed to the cold and rain; for then almoft 
all infects abftain from eating. I have neglected 
to offer them blood. 
In one of thefe Flies, which I opened alive, 
all the fat was confumed, fo that no part of it 
remained, but thofe purple little membranes, 
with which I had obferved it before furrounded. 
Laftly, near the orifice of the ovary, which 
difcharges, Tab. XLII. Fig. vii. 4, itfelf, thro’ 
two ducts, I have difcovered thofe three very 
beautiful little knots, whereof I have before made 
mention in the Nymph. The extremities of 
thofe Nymphs are twifted, /, or turned like a 
{nail-fhell: and they are then infleGed or bent, 7, 
in a fingular manner, then curled, 7, and run 
towards the laftring of the belly, and are placed @ 
near the ovary. Where thefe knots form m their 
bending, fomething like a common membrane 
joins them together. But if they be difleGted, 
there are as many pulmonary tubes feen enclofed 
therein, as they are in number. ‘The coat or 
membrane, which invefts thefe pulmonary tubes, 
entirely dries away and perifhes, if thefe are put 
on a glafs, and leaves the tubes bare with open 
cavities. By opening the faid knots alfo, one 
may turn the air-tubes out of them unhurt. | 
The ufe of thefe little parts is utterly unknown 
tome; Icannot even conjecture for what purpofe 
they are formed. There are alfo many other parts 
of this infect, concerning which Iam as much at 
a lofs. Wherefore, all who read thefe matters, as 
well as myfelf, being convinced of our igno- - 
rance therein, are obliged fubmit to before God ; 
who hath fhewn himfelf fo incomprehenfible 
and adorable in this infect. We are obliged to 
extol him with praifes, for that he hath been 
gracioufly pleafed to difcover to us fo many, and 
fuch great things in this creature. If we cultivate 
and exercife together thefe two duties under fuch 
refearches, the vifible things will ferve to excite 
and encourage us to know and fee God, from 
thofe objets which he created, and to love him 
cordially, and like children, as the {upreme ve- 
nerable Deity. 
The End of the Hiflory of the Gadfly. 
