Phere te 5) TO RY 
It was therefore an idle fancy in fome perfons, 
to think that the Snail ufes its horns, asa blind 
man does his ftick, that is, to find out the way 
it is to creep through, orto try and diftinguith, 
by its touch, whether objects are hard or {oft. 
The head of thefe Snails, in that part of it 
where the lips are fituated, refembles, in fome 
meafure, the head of a cat; and when well 
viewed, it appears like it in feveral refpects more 
evidently. 
The common houfe Snail. 
The naked houfe Snail, which is found in 
moift cellars and about the tops of cifterns, is 
naked and has no fhell, but is covered with its 
skin only. In this particular it agrees with that 
part of the covered Snail, which creeps out of 
the fhell. On the outfide it is provided with 
four horns on its head; the two uppermott 
whereof have eyes at their extremities, ‘Tab. 
VIII. fig. viz. aa, which are fituated a little 
within the margin, on that fide which lies to- 
wards the eminence placed on the back. The 
two lower horns 44 are fmaller and have no 
eyes. There is further feen on its body, that 
eminence or velabrum cc which is fixed to the 
back, and runs along the reft of the body; 
and the body is furnifhed with oblong, acute, 
and tender glandules, and variegated with black 
lines and fpots. But the horns, head, neck, 
and whatever reaches beyond the eminence, are 
adorned with many fmaller and more delicate 
glandules. On the right of the declivity of the 
neck appears an apperture d, through which 
the genital organs pufh themfelves. 
The eminence on its back itfelf, is of a dif- 
ferent colour from the reft of the body, for it is 
adorned with chanelled or crefted little grains, 
and it is moreover very beautifully variegated 
with black fpots. This is not common to all 
houfe Snails, for they differ much in colour, 
Towards the fore part, at the head, the emi- 
nence is loofe and free, but for the moft part, 
it is kept very clofe to the body, unlefs when 
any one provokes or vexes the Snail in that 
place ; for then it raifes and moves it different 
ways; and I have, for that reafon, drawn it 
as elevated in the figure. On the hinder part, 
towards the back, the eminence is very ftrongly 
joined to the body; but in its right fide opens 
an aperture, Tab. VIII. fig. vir. e, whereby 
the Snail draws air and breathes, and difcharges 
its foeces; for which ufes the verge is likewife 
appointed in the covered Snail, and with this 
verge the eminence agrees very much, fo far 
as it is placed on the fore part of the body. 
The hinder part of the body is not very re- 
markable, only in refpect of the different ftruc- 
ture of its glandules. Moreover, in both fides 
of the body is obferved a fmall, black, unequal 
margin. In fine, there is on the hinder part, 
above the tail, a prominent fubftance f like a 
Cock’s comb, which is indeed difpofed in a 
different manner in the field Snail. The Snail 
fecretes a glutinous humour from this part. 
OF VINNY St Ey GTS. 
If any one opens the eminence at the mouth 
of the air paflage with a little pair of {ciffors, 
he will fee that the inward skin is made on the 
infide like a net; which ftru@ture feems to be 
produced by the veffels diftributed through it, 
as I have likewife before fhewn in the verge of 
the covered Snail. This little net may be feen 
very beautifully through the aperture of the 
eminence on a clear day, when the Snail opens 
it; for the creature can contract it fo clofely, 
that not even a veftige of an aperture appears, 
In the cavity of this eminence, on the left fide 
of the body are feen the heart, which beats, 
together with its auricle and pericardium, and 
likewife other cavities through which the air 
paffes. But when you remove this little net 
from its place, you will fee a {mall ftone 
underneath, which is called, by authors, Lapis 
Limacis, the Snail ftone, and is faid to ferve for 
various ufes in medicine. This little ftone may 
properly be called the os thoracis, or breaft bone 
of thecreature, for it is placed in the middle of 
the thorax and back. It is of the figure of a 
{mall hollow, and fomewhat long fhell, fig, 
vill. a. and being connected in its circumference 
with various membranes, and on the upper fide 
with the little net, it is thus kept in its place. 
It is fometimes obferved to be altogether mem- 
branous, but fometimes it is pretty thick and 
all ftony, and it ferments with an acid; at 
other times, again, it becomes ftony only here 
and there, and is obferved to be interwoven 4, 
as it were, with veflels which are filled with 
{tony little grains. Hence one may underftand 
the manner of its production, which is from 
the coagulation of the ftony particles; in like 
manner as is obferved in the membranes which 
the covered Snail frames, when it lies fome 
time at reft. Thefe fhelly {tones are found in 
younger, as well as full-grown houfe Snails, 
and I have fometimes found in the largeft, very 
{mall and membranaceous ones, interwoven 
with various petrified veffels; and often in 
{maller ones, I have found them formed of 
folid ftone. Hence Iam inclined to think, that 
the Snails change this their little ftone yearly, in 
the fame manner as Craw-fith change thofe two 
femi-convex and plain ftones, which are like- 
wife placed in their,thorax, and are improperly 
called Crabs eyes. 
Near the heart is obferved a facculus calca- 
rious, or lime bag, not much different from 
that which we have defcribed in the large Snail. 
Afterwards the ftomach, inteftines, and geni- 
tal parts prefent themfelves in the abdomen. 
The ftomach is indeed pretty large and ftrong, 
and confifts of three diftin@ly vifible coats. 
The innermoft is wrinkled into plaits, and is 
of a yellow colour; the middle one is mufcu- 
lar ; the outermoft is fomewhat corrugated or 
rough, with very beautiful partitions, efpecially 
when the ftomach is empty. Diredtly before 
are feen the falival veffels, which, as well as 
thofe out of which they fpring, are fhorter than 
in the larger Snail, but they are of the fame 
texture. ‘The inteftines pafs twifting or wind- 
ing 
i 
