A
spire is a part of the coiled
shell of
molluscs. The spire consists of all of the
whorls except for the
body whorl. Each spire whorl represents a rotation of 360°. A spire is part of the shell of a
snail, a
gastropod mollusc, a
gastropod shell, and also the whorls of the shell in
ammonites, which are
fossil shelled
cephalopods. In textbook illustrations of gastropod shells, the tradition (with a few exceptions) is to show the majority of shells with the spire uppermost on the page.