"Parmacella was found by an English traveller in Mesopotamia. It has a shell covered by a shield. But you have not answered my question respecting the Limax, or slug."
"I do not recollect," replied Charles; "yet how often we see slugs!"
"If I may be allowed to answer," said Lucy, "I think that the slug has what I now understand to be a shield. I have often watched the animal contract itself, and seen a broad, flat piece upon the back, which I thought was a kind of shelter for it."
"The Limax, or slug," continued Mr. Elliot, "is, in fact, provided with a coriaceous escutcheon, or shield, beneath which the animal partly conceals itself. The Limax agrestis, or spinning-slug, has the power of suspending itself by a kind of thread, formed of the viscid substance that covers the body.
TESTACELLUS.
COLIMACEA.
"Testacellus is a very interesting genus, lately found in England: the animal has a resemblance to the common slug: it carries the shield on the hinder part of the body.
"Testacellus scutellum feeds on earth-worms, and can so much lengthen the body that it follows them under-ground.
"Our next order will show great alterations in the very large genus Helix. I shall name to you those of Lamarck.
"The third order of Mollusca, Trachelipoda, begins with a well-known genus, the snail, Helix. The term signifies that the foot is situated under the neck, or anterior part of the body. The families in this order are numerous: they are divided into two sections; the first includes those that breathe only in the air; the second those that can exist only in the water, and are furnished with a syphon.