This image shows
just a small sampling of the diversity found in gastropod shell designs.
Malacology is the study of molluscs, and across the globe there are a number of
both professional and amateur malacologists that enjoy studying and collecting
mollusc shells. Unfortunately, however, the popularity of many of the more
beautiful forms has lead to the demise of several species that are hunted and
killed exclusively for their valuable shells, which is rather like killing an
elephant for its ivory tusks! uttlefishes are
very similar to squids in their anatomy and swimming capabilities. The principal
difference between the two groups is the fact that cuttlefishes have a small,
curved shell covered by the mantle (the cuttlebone often seen in bird cages)
whereas squids have only a vestigial skeleton consisting of a curved
plastic-like support called a pen.