Te Has TORY of Iw oh 6.13. ay 
ture of the genitals out of the body, and can 
enlarge and ftiffen itfelf for that end. For this 
purpofe it has not only a mufcular texture, but 
it is likewife provided with a peculiar mutfcle a, - 
by the ftrength of which it is thruft out. 
The act of coition is performed in this man- 
ner; firft, the outward aperture of the geni- 
tals opens itfelf in the right fide of the neck, 
fig.xvit.a@; which, when it has more and 
more infenfibly dilated and expanded its ori- 
fice, then the two inward orifices, as well of 
the penis as uterus, fig. xvirr. 4, creep out 
of the body. Then the penis eredting itfelf, 
fig. xix. c, and pufhing foftly out, of one of 
thefe orifices, comes in fight ; but the other 
aperture, that of the uterus, lies open d, to re- 
ceive the penis of the other Snail at the time of 
coition. So that the penis e of the one Snail 
is put into the aperture of the neck of the 
uterus f of the other; and again, the penis of 
the latter 4 is likewife received by the aper- 
ture of the uterus g of the former. Each of 
thefe Snails being therefore excited by a reci- 
procal ftimulating impetus to venery, each 
impregnates and conceives, fertilizes and is 
fertilized, and ejects and receives the femen. 
After coition all thefe parts are drawn into 
the body; for which purpofe the penis has 
a fomewhat long and even mufcle, Tab. V. 
fig. x. p, which is inferted under the tranf- 
verfal or oblique mufcle of the abdomen, 
where the verge of the Snail’s body is: and 
that this part fhould not want fenfe, it has 
likewife a nerve g. 
The parts of the uterus have alfo their 
nerves and mufcles, fome of which may be 
feen in the neck, near the root of the four 
horns. ‘The matrix itfelf isa tender, oblong, 
white and curled ccc little tube, which ap- 
pears moft remarkable when it is diftended, 
fig. xvi. 7, with air or wind ; for then it turns 
itfelf into very admirable convolutions, being 
jointed to a ligament, fig. x. 2mm, which con- 
nects all its folds, and is of a ftronger ftructure 
than the membranous and hollow parts of the 
tube of the uterus. ‘This feems defigned for 
fome particular ufe; for it appears full of 
glands, fo that I firft took it for the ovary 
itfelf: for indeed all the veins of the uterus, 
of which there are many, are faftened in this 
ligament, and pafs through it towards the 
uterus. But, in other refpects, neither the 
uterus nor ovary, fig. x. dd, have any thing 
remarkable in them, as long as the former has 
no eggs init. The ovary is not vifible, unlefs 
it appears like an oblong, white, tender, foft 
and triangular little part, and contains a fub- 
ftance like the melt of Perch. So fmall and 
invifible are the little eggs of the Snail before 
coition ! 
Again, the uterus is faftened near the verge 
of the Snail, and is there connected with the 
upper part of the abdomen. There are like- 
wife fome mufcles which ferve to contraé the 
uterus, a larger one s, and a {maller ¢, which 
is inferted behind the long mufcle p of the 
penis. ‘The uterus has alfo its nerve v there, 
as will appear more clearly in the defcription 
of the brain; where it will likewife be thewn 
that thefe mufcles alfo give fome affiftance to 
move the brain on the inner part. 
That the penis and uterus in the Snail have 
many parts in common between them, I am 
inclined toaffert, for this reafon ; becaufe thefe 
parts are forced to move their contents through 
common paflages, as is feen in the {perm from 
the tefticles, and on other occafions. Thefe 
tefticles e, as we have before obferved, con 
fitt of a clutter or heap of oblong filaments ; 
and the fame holds in almoft all {pecies of 
this genus of infects: it is even fo univerfal, 
that it takes place in man and quadrupeds ; 
for their tefticles are formed of fuch filaments. 
There are fixty-fix of thefe threads in the 
Snail: they are of a whitifh colour, and, in 
their inward ftructure, refemble hollow tubes, 
each being clofed up at its extremity. They 
arife from two trunks, and are divided in a 
wonderful manner, as it were, into twigs, Tab.. 
V. fig. x1.”. Thefemen is of a {nowy colour, 
and of the fame thicknefs and clamminefs as 
in the males of Bees. I know nothing that 
bears a greater refemblance to this part, than 
the pancreas of fith; a defcription of which I 
have inferted in a work of Commelinus, which 
I publifhed ; and I have delineated the figures 
with my own hands. | 
The hidden appendage, fig. x. f of the 
uterus is a very beautiful, white, nervous and 
mufcular part, of a firmer fubftance and texture: 
If it be diffected, it muft be done very cautioufly 
and with an even hand : it is then difcovered, 
that at the root or bafis in the hinder part, 
it has, fig. x11. y, a globular and round little 
part in the form of a pear; from which arifes 
a fharp, hard and crooked ftyle, not unlike a 
fharp awl. This little bone being taken out 
and viewed with a microfcope, refembles a 
tranfparent, glittering, very fmall, fcale of a fith 
deprived of its fkin. At the root, fig. XIII, a; 
on the hinder part, where this little bone is 
connected to the globular little part, it exhi- 
bits fome incifions or fiffures covered with 
coats, which penetrate inwardly from the ex- 
ternal parts into its cavity. I have counted 
fourteen of thefe incifions : it appears, in gene- 
ral, equal and round 4, and ends fome:what 
fharp like a needle: then it forms, in its cir= 
cumference, four margents or prominent bor- 
ders c, between which are feen fome remark- 
able ridges and furrows. This appears very 
plain when this minute part is diffected, fig. 
xiv.é; for then it is manifeft that it is hollow 
on the infide; fo that a hair put into it, al- 
mott entirely pafles through it. Within the 
cavity of this little bone, there is contained a 
limpid or clear humour; but where its root is 
connected with the globular part, fig. x11, 4, 
it is all hollow and very tender, fo that it is 
eafily broke in that part, if it be handled in 
the leaft roughly or carelefsly. It ferments 
Q ftrongly 
