MOLLTJSCA. 
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COCKLES. IMPERIAL VOLUTli. CliOWX VOLUTE. PHOLAS. HELMET SHELL. 
Division II. MOLLUSCA. 
We now take leave of tlie Yertebrate Division of tlie Animal Kingdom, and enter upon an- 
other, formed upon altogether a different tjqie. We have just quitted the fishes, properly so 
called, but we have not yet done with the sea, their home. Notwithstanding the infinite num- 
ber of swimming fishes, there is still abundant room in the ocean and its accessories — ^bays, 
sounds, gulfs, rivers, and lalces — for another race of beings, infinitely diversified in form, and 
countless as the leaves of the forest. 
The MoUusca, our present theme, bear the general name of Shell-fish, though they do not em- 
brace all that is included in that title. Lobsters, crabs, prawns, and many other creatures that 
live in the sea, belong to another division : we now treat of oysters, clams, cockles, snails, mussels, 
and a variety of others, which produce the beautiful and diversified shells which ornament the 
cabinet of the conchologist. Though the study of these might seem httle likely to afford amuse- 
ment, we may remark that it is precisely here in this almost hidden and lost division of the 
animal kingdom, that we shall meet with some of the most interesting and instructive surprises. 
Every living creature has a history of its own ; each has characteristics by which it may be known 
from its relatives ; each has its own territory, its appropriate food, and its duties to perform in 
