spir·u·la 
(spĭryə-lə, spĭrə-)
(spĭryə-lə, spĭrə-)n. pl. spir·u·lae (-lē′)
A small squid of the genus Spirula, having a spirally coiled, chambered, internal shell often found on beaches.
[Late Latin spīrula, twisted cake, diminutive of Latin spīra, coil; see SPIRE2.]