THEA STO RY oki TONG BR Cd: Ss. 
from which the mucus or flimy moifture iffues. 
Thefe tubercles are covered with a great num- 
ber of veffels, which run between and furnifh 
_ them with matter for the’ flimy humour. 
Thefe glands projet beyond the furface of the 
skin, and are covered as it were with white 
tranfparent points, between which, as between 
ridges, or in furrows, the veffels are feen to 
creep. This order is contrary to that which 
the all-wife Creator of the world hath chofen 
in the leaves of trees; for in the latter, the 
veins and nerves are ufually fomewhat promi- 
nent, and the fucculent part is deprefled and 
placed between them. 
The greateft part of the fubfance of thefe 
fringed margins confifts of three membranes. 
The firft and uppermoft of thefe is a. glandular 
skin; the middle one is a glandular, but thin, 
membrane; and the loweft is a fomewhat 
thicker membrane {mooth and flippery. Under 
thefe the body of the Snail is interwoven with 
ftrong mufcles, by the help of which, and 
with a fingular kind of motion, refembling, 
as it were, the waves and billows of the fea, 
it moves at pleafure its fhell and whole body. 
Thefe fringes therefore perform the office of 
feet in this little animal, and they may be pro- 
petly called the general foot of the body. This 
whole part is tender and {pungy ; yet, when it 
is pricked wijh a needle, it can contract its 
mufcles with fo much force, that it draws up 
and joins itfelf together, fo as to become as hard 
as leather. 
bi 
The part of the body which lies under thefe 
is very white, and is covered with an even 
skin, which feems tome more tender than the 
former; but it is glandular like that, and is 
fitter for motion, by reafon of its finenefs. If 
the Snail be fuffered to creep, this motion may 
be obferved very beautifully; for if the glafs 
be inverted, as the Snail is creeping on it, this 
admirable motion will be perfectly confpicuous: 
it refembles {mall waves, which, when agitated 
with a gentle wind, flowly follow each other ; 
nor can I explain this motion by a more proper 
example. 
As to the motion of the animal fpirits being 
obferved, like {mall globules moving from the 
head to the tail, and again from the tail to the 
head, in a naked Snail thrown into the water ; 
it is indeed a mere chimerical notion, invented 
by thofe philofophers who make’ no experi- 
ments to guide them, but grow pale over their 
books only. The reafon of the appearance 
which gave birth to the opinion, is this, that 
when the Snail is thrown into the water, fome 
air always remains fixed in the mucus of the 
body, which never fhews any regular.or deter- 
minate motion, although it really has a very 
{trong one; for the little bubbles always retain 
their order and fituation among themfelves, 
though they are contracted and expanded with 
the body ; that is, they are heaped one upon 
another, and again feparated from each other 
from time to time. 
og 9 asl yea Sesh Oi 
Of the attions, and of the firength and life of the Snail. 
How it is to be 
killed for diffection, with further experiments ; and an account of the effect falt 
has on this creature. 
HLEN Snails are difpofed to reft, fo 
as to remain quiet without any motion 
of their verge or foot, they difcharge a great 
quantity of flimy matter from their bodies, 
which, when dried, anfwers the purpofe of a 
couch or hammock, in which they reft. This 
they do in the day-time, and they will lie in 
»this manner as long as it rains, or the atmof- 
phere continues cool; for nothing diftreffes 
them more than drought. 
From this we learn alfo, that their flimy 
humour, which, at other times is clear and 
white, is more coloured, or has greater variety 
of tincts, the lefs of it they have in their veffels 
and glands. 
Thefe creatures are very fond of company 
at the time they are increafing their fhell, for 
then hundreds of them gather together in thady 
places, that they may be at leifure for that bu- 
finefs, lying quiet and clofe to each other, efpe- 
cially for fome days before they begin to copu- 
late ; as I fhall fhew in its proper place. 
Life is very ftrong in them, infomuch that 
they will live fix or feven days under water. 
Nay, if they are wounded, and even dragged 
from their skin or fhell, they will (till live four 
days, provided they are put into water. They 
are fo ftrong, that they can very eafily creep 
forward, and move themfelves to all quarters, 
with another Snail fticking to their fhell; nay, 
one will fometimes draw two others. The 
period of their natural lives cannot be certainly 
determined, but Iam inclined to think they 
live toa very great age, which may be pro- 
bably conjectured from the flow increafe of 
their fhell: on the furface of their hells are 
feen a very great number of the fame kind of 
marks, Tab. IV. fig. 11. s, obfervable in a 
cow’s horn, from which the country people 
compute the age of that creature. 
The diffecting Snails has coft me great la- 
bour; for this operation is very difficult, and 
muft be performed whilft they are living. If 
we {prinkle the Snail with falt, it is not con~ 
fumed, as is generally thought, but only killed, 
and then the ftrong contraction of the muf- 
cles draws up all the internal parts to fuch a 
degree, that nothing can be feen diftin@ly. All 
the 
