Adaptation
The Olive Vertigo moves by creeping on a flat "foot"
underneath the body. The muscles of the foot contract and expand
and to creates a rippling movement that slides the snail along.
The "foot" has a special gland that produces a slimy mucus to
make a special track. The slime is secreted from the front of
the foot and hardens when exposed to air. (Tryon 1918)
Its soft body is protected by a hard shell. When its disturbed,
it will withdraw or pull itself back inside its shell. A snail
is most active at night and on cloudy days, as the sun can dry
it out. During very cold weather or winter, it hibernates in the
ground. (Löve 1963)