Aplysia, or Sea-hare.
Dolabella.

"One species of Aplysia is found on the Devonshire coast: the name Sea-hare marks the singularity of the two tentacula, which resemble the ears of the hare. The body is folded up in a loose skin, or mantle: upon the middle of the back it carries a circular shield, thin, transparent, and yellowish, in which it resembles the slug. These animals swim with ease.

"Dolabella resembles the Aplysia in some degree; the genus is foreign, and one species is known to inhabit the bays of the Isle of France, where it covers itself with a portion of mud."

"I cannot understand why animals related to the slugs should find a place here," said Charles.

"Have not slugs the characteristics of the Mollusca class?" asked his father. "And are you quite sure that they are without a shell?

ONCHIDIUM.
LIMAX.

"Our next family, the Limacina, has

Onchidium.
Parmacella.
Limax, slug.
Testacella.
Vitrina.

"Onchidium is a genus from the shores of the Indian seas. The animals have a shield: they live near the sea, and some are known to swim, often coming to the surface to breathe the air.