"N. polìta is a handsome shell: it is thick, polished, and variously marked; the base of the aperture is yellowish.
"N. peloronta, the bleeding-Nerite, is marked with a crimson spot.
"N. tessellata is sulcated, or furrowed, chequered with black and white.
"Natìca differs from the former genera in these particulars: the shell is umbilicated; the left-margin oblique, not toothed, callous, the callosity sometimes covering the umbilicus. The species are numerous, and several are common in collections. "N. aurantius and N. millepunctata are good shells.
IANTHINA.
SIGARETUS.
STOMATELLA.
"Ianthina is the last of the snail-like genera. Its beautiful purple colour renders the shell a favourite. They are marine, though so fragile and transparent. The animal floats upon the surface of the sea, by means of a vesicular appendage to the foot, which, it is said, may be inflated or contracted at pleasure. Ianthina shines by night. I. communis is found in abundance in the Atlantic and in the Mediterranean.
"The family Macrostoma contains,
| Sigaretus | Helix? |
| Stomatella. | |
| Stomatia. | |
| Haliòtis | Haliòtis, sea-ear. |
"These genera form a beautiful family, and all bear a resemblance to the human ear.