COWRIES. 165 
The characters of the family are the following: 
the form is oval, flattened on one side, on which is 
placed the aperture; this is as long as the shell, 
narrow, and open at each end: the spire in the 
adult state is entirely concealed: the outer lip is in 
general bent inward and thickened. The surface 
of the shell is often highly polished, with a glassy, 
or porcelain-like enamel, with no trace of an epi- 
dermis, or investing coat of skin. 
The animal is large ; the mantle is developed 
into widely-expanded lateral lobes, which are, 
during activity, turned upward on each side, so as 
closely to embrace the shell. These lobes are gene- 
rally gaily coloured, and are often adorned with 
various fringes and other appendages. The head is 
furnished with a retractile proboscis, and with a 
muzzle. The gill-plume is single. The sexes are 
separate. ‘There is no operculum. 
“The difference of aspect,” observe Messrs. 
Forbes and Hanley, “between these mollusks 
when crawling, with all their beautifully-coloured 
soft parts exposed, often completely concealing 
their enamelled shells, and their appearance when, 
after being seized, they suddenly and instan- 
taneously withdraw their bodies and mantle-lobes, 
and expose the shell only, is very curious and 
surprising.’ * 
GENUS CYPRZA. 
As specimens of some or other of the numerous 
species that compose this beautiful genus may be 
found on almost every mantlepiece, sideboard, and 
* Brit. Mollusca, iti. 493. 
