216 
NATURAL HISTORY. 
of all the sea contains at present ; as the earth furnishes 
many kinds which our most exact and industrious shell- 
collectors have not been able to fish up from the deep. 
Univalve or Turbinated Shell-Jish. 
To conceive the manner in which these animals subsist that 
are hid from us at the bottom of the deep, we must again 
have recourse to one of a similar nature and formation, that 
we know, viz. the garden-snail. It is furnished with the 
organs of life in a manner almost as complete as the largest 
animal; with a tongue, brain, salival ducts, glands, nerves, 
stomach, and intestines, liver, heart and blood-vessels : be- 
sides these, it has a purple bag that furnishes a red matter to 
different parts of the body, together with strong muscles 
that hold it to the shell, and which are hardened, like ten- 
dons, at their insertion. 
But these it possesses in common with other animals. We 
must now see what it has peculiar to itself. The first striking 
peculiarity is, that the animal has got its eyes on the points 
of its largest horns. When the snail is in motion four horns 
are distinctly seen ; but the two uppermost and longest de- 
serve peculiar consideration, both on account of the various 
motions with which they are endued, as well as their having 
their eyes fixed at the extreme ends of them. The eyes the 
animal can direct to different objects at pleasure, by a regu- 
lar motion out of the body ; and sometimes it (tides them, 
by a very swift contraction into the belly. Under the small 
horns is the animal’s mouth ; and though it may appear too 
soft a substance to be furnished with teeth, yet it has not 
less than eight of them, with which it devours leaves, and 
other substances, seemingly harder than itself ; and with 
which it sometimes bites off pieces of its own shell. 
At the expiration of eighteen days after coition, the snails 
produce their eggs, and hide them in the earth with the 
greatest solicitude and industry. These eggs are in great 
numbers, round, white, and covered with a soft shell : they 
are also stuck to each other by an imperceptible slime; like 
a bunch of grapes, of about the size of a small pea. 
The snail is possessed not only of a power of retreating 
into its shell, but of mending it when broken. Sometimes 
these animals are crushed seemingly to pieces; and to all 
appearance utterly destroyed ; yet still they set themselves 
to work, and, in a few days, mend all their numerous breaches. 
The same substance by which the shell is originally made, 
goes to the re-establishment of the ruined habitation. 
As the snail is furnished with all the organs of life and sen- 
