Snails belong to the Mollusca. Mussels belong to this clade too but snails are much more speciose - there are about 43’000 kinds of snails! I like our garden snails with a shell (we call it house) on their back. Depending on the type of snail that shell comes in a various shape, but all snail shells are twisted in the same direction: rightwards. Sometimes there’s a snail with a leftwards twisted shell. That’s very very rare and we call these snails “snail kings”. Oooohhh, I wish I would find such a snail or (even better) a shell of a snail king. Oh I wish it so hard!
|Here some different shapes and sizes of land snail shells. You can find such shells in the garden and forest. I really like the striped one. The right one is a Alinda biplicata.|
Actually snail shells are just white because they are made of chalk. But there’s a second layer, a kind of skin (periostracum) over it. This skin makes the shell colorful.
|Here you can see the periostracum very well.|
The “house” of a snail is an amazing thing. A muscle is connected with the shell so within a few seconds the snail retracts itself into it, safe and sound of dryness, cold, injuries and predators. If the shell of a snail is damaged, glands emit chalk which will repair the damage as good as possible.
|It will survive.|
Cross-section of a large garden snail shell. It’s loopy inside as well.
|That might get a little hairy... Helicodonta obvoluta.|
|And last but not least: The large garden snail (Helix pomatia).|