RAM'S HORN SHELL
This is the white, openly coiled shell about an inch across which is washed ashore in great numbers on our west coast beaches. Note the compartments, with pearly partitions, each connected to the next by a tiny tube. This shell is internal in the body of a small squid. Until a few years ago the living animal of Spirula was practically unknown, until it was found that they live in oceanic waters at depths of 100–1,100 fm. They seldom approach the surface and are never taken on the sea bed.
by Arthur William Baden Powell, Assistant Director, Auckland Institute and Museum.