Helix aspersa aspersa

The direction a gastropod’s shell is coiled in depends on the species. For example, the edible garden snail, Helix aspersa aspersa, has a dextral (right-handed, from the Latin ‘dexter’, meaning “right”) shell: it coils in a clockwise direction from the opening. When the spiral goes the other way, it is called a sinistral shell (from the Latin ‘sinister’, meaning “left”). Specimens from the Dautzenberg Collection