GASTROPODA
Athleta luctator

Gastropoda are a class of the phylum mollusca (molluscs). Gastropods usually have a coiled shell into which the animal can retreat. They are known from the Cambrian and live in water and on land.

This picture shows Athleta luctator from the Eocene Barton Clay of Hampshire England.

Eocene gastropod, Athleta luctator, from the Barton clay, Hampshire, England